CERN: Feature https://home.cern/ en CERN70: The heart of CERN’s accelerator chain https://home.cern/news/series/cern70/cern70-heart-cerns-accelerator-chain <div class="layout layout__region featured-story-page-node-layout-content"> <div class="field--items"> <div class="field--item"> <div class="component-row component-row__display__fluid section-navigation component-row__has-header effect_none is_half_height"> <div class="background__veil"></div> <div class="background-component background__image" style="background:url(&#039;/sites/default/files/2024-02/5901257-min-crop2.jpg&#039;) no-repeat center top / cover; height: 100%;"></div> <div class="component-row__row"> <div class="component-row__column component-row__center section-has-no-column col-md-12 col-sm-12 col-xs-12"> <div class="box-effects-wrapper "> <div class="cern-component-header-blocks component-header"> <div id="header-blocks--2" class="owl-carousel owl-theme component-header__carousel header-carousel"> <div class="header-block"> <div class="header-block__title"> <h3 class="header-block__name" > <span>CERN70: The heart of CERN’s accelerator chain</span> <span class="header-block__name__underline"></span> </h3> <span class="header-block__subhead" ><p class="text-align-center">29 February 2024 · <i>Voir en <a href="/fr/news/series/cern70/cern70-heart-cerns-accelerator-chain">français</a></i></p> <hr /><p class="text-align-center"><strong>Part 4</strong> of the <strong><a href="/news/series/cern-70">CERN70</a></strong> feature series<br /><br /><strong>Günther Plass</strong>, former Director of Accelerators at CERN, joined the Magnets group at the Proton Synchrotron (PS) in 1956.<br /> Three years later, the machine went into service and became the most powerful accelerator in the world</p> </span> </div> </div> </div> </div> <a class="endof-cern-header-blocks"></a> </div> </div> </div> </div> </div> <div class="field--item"> <div class="component-row component-row__display__centered section-navigation effect_none"> <div class="component-row__row"> <div class="component-row__column component-row__center section-has-no-column col-md-12 col-sm-12 col-xs-12"> <div class="box-effects-wrapper "> <div class="component-margin component-margin-medium" ></div> <div class="text-component text-component-page clearfix"> <div class="text-component-text cern_full_html"> <figure role="group" class="align-right"><img alt="Aerial view of CERN" data-entity-type="file" data-entity-uuid="94ddae6c-c590-4115-8a84-5bb7c3f9a2f2" height="auto" src="/sites/default/files/inline-images/katebrad/5901257-min-crop2.jpg" width="1440" loading="lazy" /><figcaption>Aerial view of the CERN site and the PS ring in April 1959 (Image: <a href="http://cds.cern.ch/record/40906">CERN</a>)</figcaption></figure><p>In 1957, CERN staff moved into the new buildings on the Meyrin site in Geneva, and the rooms were rapidly filled with equipment for the Proton Synchrotron (PS).</p> <p>By the end of July 1959, assembly of the PS – the accelerator is more than 600 metres in circumference! - was completed and, on 16 September, the first beam was circulated. On 24 November 1959, the PS accelerated protons for the first time to its nominal energy of 24 gigaelectronvolts (GeV).</p> <p>The machine is based on a revolutionary new concept developed at Brookhaven National Laboratory in the United States, which makes it possible, for the same budget, to achieve a much higher particle energy than with a traditional synchrotron. In this way, the young Laboratory demonstrated its ability to translate a new concept into reality.</p> <p>Even today, 65 years later, the PS is the heart of CERN's accelerator chain. And while the machine has of course undergone many phases of improvement, its fundamental structure has remained unchanged.</p> </div> </div> <div class="text-component text-component-page clearfix"> <h2 class="text-component-title"> Recollections </h2> <div class="text-component-text cern_full_html"> <blockquote>Physicists from a dozen European countries would work together on the construction, and later the use, of this almost unbelievable machine, which would stretch technologies to their very limits.<br /><em><strong>Günther Plass</strong></em></blockquote> <figure role="group" class="align-left"><img alt="People sitting on top of a large magnet" data-entity-type="file" data-entity-uuid="faded21b-9943-47c9-a8fb-96fb80e2aa61" height="auto" src="/sites/default/files/inline-images/katebrad/5600555-min.jpg" width="1440" loading="lazy" /><figcaption>Completion of the first PS magnet unit was celebrated by photographing the entire Magnet group sitting on it. This first magnet unit was named Margherita, after group member Margherita Cavallaro, shown here holding a sign. Günther Plass is fourth from the left. (Image: <a href="http://cds.cern.ch/record/767883">CERN</a>)</figcaption></figure><p>Günther Plass joined the Proton Synchrotron (PS) team in 1956 and worked for 25 years on PS-related assignments. In the 1980s, he became Deputy Project Leader of the Large Electron Positron Collider (LEP), before becoming CERN's Director of Accelerators.</p> <p>“A dream began for me in autumn 1954 at the annual meeting of the German Physical Society. At that gathering, an enthusiastic Werner Heisenberg spoke of recent meetings preparing for CERN, a European Laboratory for Fundamental Physics just being launched in Geneva. A pioneering European enterprise, the new laboratory was to build a particle accelerator hundreds of metres in circumference, huge compared to the cyclotrons I had been reading about at the time. Physicists from a dozen European countries would work together on the construction, and later the use, of this almost unbelievable machine, which would stretch technologies to their very limits.</p> <p>I certainly wasn’t the only one to be deeply impressed by this report. I even nurtured the hope that my moderate command of languages might one day help me to participate in that enterprise. Back in 1950, I had spent several weeks on a language course in Dijon, France, and in 1951 I spent another few weeks picking potatoes along with students from several countries near Hull in the United Kingdom.</p> <figure role="group" class="align-right"><img alt="Man holding bottle in front of blackboard of equations" data-entity-type="file" data-entity-uuid="c980654d-3ff4-4498-9017-234fdc8c3e6a" height="auto" src="/sites/default/files/inline-images/katebrad/icon1440-SPECIAL_X_CERN_00193_0165-crop-min.jpg" width="1347" loading="lazy" /><figcaption>On 25 November 1959, in front of the CERN staff gathered in the Main Auditorium, John Adams, then Director of the PS division, held a bottle of vodka in his hands. The bottle had been given to him a few months earlier on a trip to Dubna, in the Soviet Union, where the world's most powerful accelerator, the Synchrophasotron, had just been commissioned. The bottle was only to be opened if Dubna's record energy of 10 GeV was exceeded. On 24 November, the PS circulated protons at more than twice that energy, 24 GeV. Before sending the empty bottle back to the Soviet Union, John Adams placed inside it a photograph of the 24 GeV pulse, as proof of the record. (Image: <a href="http://cds.cern.ch/record/761802">CERN</a>)</figcaption></figure><p>About one and a half years after Heisenberg’s presentation, I learned that my current [magnet] specialisation was in demand for CERN’s project, so I rushed off my application and, much to my surprise, was offered a job. On 18 June 1956, I dutifully reported to the PS Division’s secretariat at the Institute of Physics. I was directed to join my future colleagues in the lecture hall, where a Symposium on Particle Accelerators and Pion Physics was under way. I thus began my career by listening to talks about pions, muons and strange particles — what a mysterious new world I had come into!”</p> <p>----</p> <p><em>This interview is adapted from the 2004 book “Infinitely CERN”, published to celebrate CERN’s 50th anniversary. Günther Plass <a href="/news/obituary/cern/gunther-plass-1930-2020">passed away in 2020</a>, aged 90.</em></p> </div> </div> </div> </div> </div> </div> </div> <div class="field--item"> Günther Plass, former Director of Accelerators at CERN, joined the Magnets group at the Proton Synchrotron (PS) in 1956. Three years later, the machine went into service and became the most powerful accelerator in the world </div> </div> </div> Tue, 27 Feb 2024 16:48:39 +0000 katebrad 189541 at https://home.cern Suffer or enjoy? https://home.cern/news/series/work-well-feel-well/suffer-or-enjoy <div class="layout layout__region featured-story-page-node-layout-content"> <div class="field--items"> <div class="field--item"> <div class="component-row component-row__display__fluid section-navigation component-row__has-header effect_none is_half_height"> <div class="background__veil"></div> <div class="background-component background__image" style="background:url(&#039;/sites/default/files/2024-02/WWFW-3-min-crop.jpg&#039;) no-repeat center top / cover; height: 100%;"></div> <div class="component-row__row"> <div class="component-row__column component-row__center section-has-no-column col-md-12 col-sm-12 col-xs-12"> <div class="box-effects-wrapper "> <div class="cern-component-header-blocks component-header"> <div id="header-blocks--2" class="owl-carousel owl-theme component-header__carousel header-carousel"> <div class="header-block"> <div class="header-block__title"> <h3 class="header-block__name" > <span>Suffer or enjoy? </span> <span class="header-block__name__underline"></span> </h3> <span class="header-block__subhead" ><p class="text-align-center">By: <a href="/authors/hr-department"><span class="cern-tag">HR department</span></a></p> <p class="text-align-center">28 February, 2024 · <i>Voir en <a href="/fr/news/series/work-well-feel-well/suffer-or-enjoy">français</a></i></p> <hr /><p class="text-align-center"><strong>Part 3</strong> of the <strong><a href="/news/series/work-well-feel-well/">Work Well Feel Well</a> series</strong> looks at <strong>recognising and learning from emotions</strong></p> </span> </div> </div> </div> </div> <a class="endof-cern-header-blocks"></a> </div> </div> </div> </div> </div> <div class="field--item"> <div class="component-row component-row__display__centered section-navigation effect_none"> <div class="component-row__row"> <div class="component-row__column component-row__center section-has-no-column col-md-12 col-sm-12 col-xs-12"> <div class="box-effects-wrapper "> <div class="text-component text-component-page clearfix"> <h2 class="text-component-title"> Sphere of control </h2> <div class="text-component-text cern_full_html"> <p><strong><img alt="Graphic of part 3 of Work Well Feel Well series" data-entity-type="file" data-entity-uuid="ef8c5afb-0b46-4fee-81c6-adba8881c0a4" height="auto" src="/sites/default/files/inline-images/katebrad/WWFW_screen_Intention.jpg" class="align-right" width="1920" loading="lazy" />What we experience</strong> in life can be out of our control. What we can control, however, is <strong>how we react</strong>. This doesn’t mean staying positive in every situation and hence suppressing or ignoring how we really feel. <strong>All emotions are valid</strong> and deserve to be acknowledged and accepted. They <strong>provide useful signposts</strong>, such as anger indicating when a boundary has been crossed.</p> <p>In challenging situations, it helps to understand what we can control or influence, and what we can’t. This <strong>sphere of control</strong> gives us the clarity to move forward, <strong>changing what we can</strong> and <strong>accepting what we can’t</strong>.</p> <figure role="group" class="align-right"><img alt="Large circle with two circles within in" data-entity-type="file" data-entity-uuid="79f16f9e-8d0a-4bbf-a802-b7cfeb5b3ac8" height="auto" src="/sites/default/files/inline-images/katebrad/SphereControl.png" width="1085" loading="lazy" /><figcaption>The sphere of control: change what you can, accept what you can’t</figcaption></figure><p>We can take back more control of a situation by reaffirming our boundaries and saying no. There are many examples of <strong>saying no respectfully</strong> to protect ourselves from becoming overloaded. Here are just a few:</p> <ul><li>Thank you for thinking of me, but I can’t.</li> <li>Unfortunately, it’s a not a good time.</li> <li>It isn’t possible with my current workload.</li> <li>I have other priorities that are more important at the moment.</li> <li>I’m not able to prioritise that right now.</li> <li>I already have plans. Perhaps next time.</li> </ul><p>We experience a range of emotions each day. Taking a moment to <strong>observe our emotions</strong> and <strong>develop a plan or intention</strong> (see exercise below) that is respectful of our needs, can guide and help us to enjoy a balanced position to external pressures.</p> </div> </div> <div class="text-component text-component-page clearfix"> <h2 class="text-component-title"> Take action </h2> <div class="text-component-text cern_full_html"> <p>As part of the “Efficiency and caring at work” campaign, the <a href="https://hr.web.cern.ch/work-well-feel-well">Work Well Feel Well website</a> now offers useful resources that can be downloaded, including an <a href="https://hr.web.cern.ch/sites/default/files/2024-02/RDV3_INTENTION_A4_exercice_EN.pdf">exercise</a> on observing emotions, defining needs and developing a plan or intention.</p> <p>In addition:</p> <ul><li>The <a href="https://indico.cern.ch/event/1335703/timetable/">recording</a> of the recent Micro-talk #8 “<em>Ego vs Innovation : le regard des neurosciences cognitives</em>” (in French) reinforces how we can learn from our emotions and our errors.</li> <li>The CERN Medical Service <a href="https://hse.cern/content/mental-health-support">mental health support</a> resources include a self-assessment and contact details of the CERN psychologists.</li> <li>The <a href="https://ombuds.web.cern.ch/">CERN Ombud</a> articles “<a href="https://ombuds.web.cern.ch/blog/2023/09/feeling-beyond-help">feeling beyond help</a>” and “<a href="https://ombuds.web.cern.ch/blog/2023/06/managers-and-burnout-put-your-own-oxygen-mask-first">put your own oxygen mask on first</a>” are also relevant to this topic.</li> </ul><p>This is the third of a 12-part <a href="https://home.cern/news/series/work-well-feel-well/">Work Well Feel Well</a> series, with articles publishing every two months. </p> </div> </div> </div> </div> </div> </div> </div> <div class="field--item"> Part 3 of the Work Well Feel Well series looks at recognising and learning from emotions </div> </div> </div> Fri, 16 Feb 2024 07:03:41 +0000 katebrad 189470 at https://home.cern CERN70: A first discovery https://home.cern/news/series/cern70/cern70-first-discovery <div class="layout layout__region featured-story-page-node-layout-content"> <div class="field--items"> <div class="field--item"> <div class="component-row component-row__display__fluid section-navigation component-row__has-header effect_none is_half_height"> <div class="background__veil"></div> <div class="background-component background__image" style="background:url(&#039;/sites/default/files/2024-02/SC-min_0.jpg&#039;) no-repeat center top / cover; height: 100%;"></div> <div class="component-row__row"> <div class="component-row__column component-row__center section-has-no-column col-md-12 col-sm-12 col-xs-12"> <div class="box-effects-wrapper "> <div class="cern-component-header-blocks component-header"> <div id="header-blocks--4" class="owl-carousel owl-theme component-header__carousel header-carousel"> <div class="header-block"> <div class="header-block__title"> <h3 class="header-block__name" > <span>CERN70: A first discovery</span> <span class="header-block__name__underline"></span> </h3> <span class="header-block__subhead" ><p class="text-align-center">14 February 2024 · <i>Voir en <a href="/fr/news/series/cern70/cern70-first-discovery">français</a></i></p> <hr /><p class="text-align-center"><strong>Part 3</strong> of the <strong><a href="/news/series/cern-70">CERN70</a></strong> feature series<br /><br /><strong>Giuseppe Fidecaro</strong> was among the small group of physicists who performed the first experiment at CERN to provide results in 1958 that would spread the Laboratory’s name around the world</p> </span> </div> </div> </div> </div> <a class="endof-cern-header-blocks"></a> </div> </div> </div> </div> </div> <div class="field--item"> <div class="component-row component-row__display__centered section-navigation effect_none"> <div class="component-row__row"> <div class="component-row__column component-row__center section-has-no-column col-md-12 col-sm-12 col-xs-12"> <div class="box-effects-wrapper "> <div class="component-margin component-margin-medium" ></div> <div class="text-component text-component-page clearfix"> <div class="text-component-text cern_full_html"> <figure role="group" class="align-right"><img alt="CERN's first accelerator, the Synchrocyclotron (SC), in 1957" data-entity-type="file" data-entity-uuid="47eb598b-2899-4d37-a968-0d9f3810fd27" height="auto" src="/sites/default/files/inline-images/katebrad/SC-min.jpg" width="5289" loading="lazy" /><figcaption>The 600 MeV Synchrocyclotron (SC) was CERN’s first accelerator. It began operation in 1957 and ran for 33 years. The SC is now one of the visit points for CERN guided tours. (Image: <a href="http://cds.cern.ch/record/761023">CERN</a>)</figcaption></figure><p> </p> <p>A few months after CERN’s first accelerator, the <a href="/science/accelerators/synchrocyclotron">Synchrocyclotron (SC)</a>, was commissioned, a first experiment was launched. At the time, weak interactions were among the most hotly debated topics in high-energy physics. Scientists were puzzled, for example, about the decay of the particle known as the pion. The particle was known to decay into two other particles: a muon and a neutrino. According to theory, it should also sometimes decay into an electron and a neutrino, but this type of decay had never been observed before.</p> <p>In August 1958, at CERN’s Synchrocyclotron, Tito Fazzini, Giuseppe Fidecaro, Alec Merrison, Helmut Paul and Alvin Tollestrup observed this decay for the first time, at a rate in line with predictions of the theory of the weak interaction.</p> <p>It was CERN’s first major discovery.</p> </div> </div> <div class="text-component text-component-page clearfix"> <h2 class="text-component-title"> Recollections </h2> <div class="text-component-text cern_full_html"> <blockquote>We decided to present what we already had – 40 events, from a total of 124 photographs, at a rate compatible with theory […] Next day the news had gone around the world.<br /><strong><em>Giuseppe Fidecaro </em></strong></blockquote> <p>Giuseppe Fidecaro arrived in Geneva in 1956, after spending two years at Liverpool University's synchrocyclotron. He was one of the small group of physicists who performed the first experiment at CERN to provide results that would spread the Laboratory’s name around the world.</p> <figure role="group" class="align-left"><img alt="SC buidling from outside in 1958" data-entity-type="file" data-entity-uuid="4db8b588-cf4e-4484-b928-50ef648769ed" height="auto" src="/sites/default/files/inline-images/katebrad/SC-outside-min.jpg" width="5138" loading="lazy" /><figcaption>The Synchrocyclotron (SC) building with the Jura mountains in the background, photographed in December 1958. (Image: <a href="http://cds.cern.ch/record/761051">CERN</a>)</figcaption></figure><p>“The basic idea of the experiment was that the beam of pions would be stopped in a scintillation counter. Our experimental set-up consisted of a telescope made of a sandwich of graphite plates and scintillation counters. The output signals were displayed on the screen of a high-speed oscilloscope and photographed on continuously moving film. We could recognise the decay of the pion from the recorded signal. With its twelve counters, it was a rather complex and sophisticated apparatus for its time!</p> <p>In August 1958, we finally got beam to our apparatus. After some checks, we went on changing the thickness of the telescope. A thin telescope simply gave muon and neutrino decay signatures. When we inserted the last graphite plate, we weren't really prepared for what was going to happen. Tito Fazzini, Alec Merrison, Helmut Paul, Alvin Tollestrup and I observed what no one else in the world had seen before: the film essentially showed electron and neutrino decay signatures. We had pion-electron events! A few days later, Julius Ashkin joined our experiment.</p> <p>On 1 September, the second United Nations International Conference on the Peaceful Uses of Atomic Energy opened its doors in Geneva. Our results couldn’t be hidden from the large number of physicists, journalists etc. who had come from all over the world for the conference. Although the experiment was not yet complete, we decided to present what we already had – 40 events, from a total of 124 photographs, at a rate compatible with theory – at a special session of the conference on Thursday 4 September, only one month after we got the first beam. The next day, the news had gone around the world. For the first time the local newspaper Tribune de Genève announced “Discovery at CERN”. Our first paper was accepted for publication one week later, and the final paper appeared in July 1959.</p> <figure role="group" class="align-right"><img alt="Male and female next to apparatus" data-entity-type="file" data-entity-uuid="ed84ce18-c0da-4f10-9f7d-460fbe730dfb" height="auto" src="/sites/default/files/inline-images/katebrad/6411020-min.jpg" width="1440" loading="lazy" /><figcaption>Giuseppe and Maria Fidecaro, pioneers of CERN's experiments, became key figures in the Laboratory, continuing to work until very recently. Read the <a href="https://cerncourier.com/a/maria-fidecaro-1930-2023/">CERN Courier tribute</a> to Maria, who passed away last September. (Image: <a href="http://cds.cern.ch/record/763164">CERN</a>)</figcaption></figure><p>Our approach had been purely experimental, typical of a university lab. An old problem had suddenly turned hot and we looked at whether it could be solved with existing equipment. An experiment using a range telescope had failed to find the missing decay a few years earlier. We could repeat it – but with a minor modification: pions would stop in a scintillator, not within an inert target. A so-called travelling wave oscilloscope was already in our hands! Marc Fell and Max Renevey only had to build a few light-guides and mechanical supports. All this took place in an atmosphere full of enthusiasm.</p> <p>CERN hosted the Rochester Conference [now ICHEP (International Conference on High Energy Physics)] in June 1958, less than two months after our work had begun. Our apparatus was set up in the “neutron hall” of the SC, and the conference participants were able to see it. To some of them, the telescope looked quite simplistic, compared to the enormous magnet used for the same purpose in Chicago the previous year, but without success.</p> <p>There were additional firsts in this experiment. The programme written for CERN's brand-new Mercury computer, designed to determine the efficiency of our apparatus, was the first “Monte Carlo” programme – based on a randomised simulation – written for an experiment at CERN. Together with Yves Goldschmidt-Clermont and Norman Lipman, we were also able to measure the average lifetime of the pion with improved precision. To do this, we used the first instrument developed at CERN to evaluate photos, IEP, which, while we waited for the bubble chamber images, enabled us to evaluate the 10 000 events recorded with our apparatus”.</p> <p>---</p> <p><em>This interview is adapted from the 2004 book “Infinitely CERN”, published to celebrate CERN’s 50th anniversary.</em></p> </div> </div> </div> </div> </div> </div> </div> <div class="field--item"> Giuseppe Fidecaro was among the small group of physicists who performed the first experiment at CERN to provide results in 1958 that would spread the Laboratory’s name around the world </div> </div> </div> Mon, 12 Feb 2024 15:35:34 +0000 katebrad 189445 at https://home.cern CERN70: The Laboratory takes shape https://home.cern/news/series/cern70/cern70-laboratory-takes-shape <div class="layout layout__region featured-story-page-node-layout-content"> <div class="field--items"> <div class="field--item"> <div class="component-row component-row__display__fluid section-navigation component-row__has-header effect_none is_half_height"> <div class="background__veil"></div> <div class="background-component background__image" style="background:url(&#039;/sites/default/files/2024-01/5405001-A4-at-144-dpi.jpg&#039;) no-repeat center top / cover; height: 100%;"></div> <div class="component-row__row"> <div class="component-row__column component-row__center section-has-no-column col-md-12 col-sm-12 col-xs-12"> <div class="box-effects-wrapper "> <div class="cern-component-header-blocks component-header"> <div id="header-blocks--6" class="owl-carousel owl-theme component-header__carousel header-carousel"> <div class="header-block"> <div class="header-block__title"> <h3 class="header-block__name" > <span>CERN70: The Laboratory takes shape</span> <span class="header-block__name__underline"></span> </h3> <span class="header-block__subhead" ><p class="text-align-center">1 February 2024 · <i>Voir en <a href="/fr/news/series/cern70/cern70-laboratory-takes-shape">français</a></i></p> <hr /><p class="text-align-center"><strong>Part 2</strong> of the <strong><a href="/news/series/cern-70">CERN70</a></strong> feature series<br /><br /><strong>Franco Bonaudi</strong>, one of the pioneers of CERN's accelerators, looks back at the Laboratory's early years, during which everything had yet to be invented</p> </span> </div> </div> </div> </div> <a class="endof-cern-header-blocks"></a> </div> </div> </div> </div> </div> <div class="field--item"> <div class="component-row component-row__display__centered section-navigation effect_none"> <div class="component-row__row"> <div class="component-row__column component-row__center section-has-no-column col-md-12 col-sm-12 col-xs-12"> <div class="box-effects-wrapper "> <div class="component-margin component-margin-medium" ></div> <div class="text-component text-component-page clearfix"> <div class="text-component-text cern_full_html"> <figure role="group" class="align-right"><img alt="Two men looking out at a field where a worksite begins" data-entity-type="file" data-entity-uuid="92c18e08-d428-4940-9608-ea632d3e59c5" height="auto" src="/sites/default/files/inline-images/katebrad/5405001-A4-at-144-dpi.jpg" width="1448" loading="lazy" /><figcaption>On 17 May 1954, the ground-breaking ceremony for the construction of the European Laboratory for Particle Physics took place on the Meyrin site in Geneva, before the eyes of Geneva civil servants and CERN staff. (Image: <a href="https://cds.cern.ch/record/39595">CERN</a>)</figcaption></figure><p>Geneva was chosen as the site of the CERN Laboratory at the third session of the Provisional Council in 1952. The city’s central position in Europe, its neutrality during the war and the fact that it was already home to international organisations played a decisive role.</p> <p>Construction of the Laboratory began in 1954. While waiting for their premises, the first members of the CERN community moved into the Geneva Institute of Physics and worked from a building and barracks near the airport. The theory group had already been founded in 1952 at the Institute of Theoretical Physics in Copenhagen alongside the Nobel Prize-winning physicist Niels Bohr. It moved to Geneva in 1957.</p> <p>Two accelerator projects were launched in parallel: an innovative accelerator of unprecedented power, the Proton Synchrotron (PS), and, pending its commissioning, a more conventional machine, the Synchrocyclotron (SC). The SC, built in just three years, went into service in 1957, enabling physicists to get CERN's first experiments up and running quickly.</p> </div> </div> <div class="text-component text-component-page clearfix"> <h2 class="text-component-title"> Recollections </h2> <div class="text-component-text cern_full_html"> <blockquote>We all started together in huts at Geneva airport in 1954 ... about 150 people of all nationalities. We quickly got used to working together and communicated with each other in bad English.<br /><strong><em>Franco Bonaudi</em></strong></blockquote> <figure role="group" class="align-right"><img alt="Black-and-white image of a construction site" data-entity-type="file" data-entity-uuid="7b16318f-4ef9-4cab-8058-6c5f37131ccc" height="auto" src="/sites/default/files/inline-images/katebrad/263.jpg" width="5092" loading="lazy" /><figcaption>The Synchrocyclotron building in November 1955, during its construction. (Image: <a href="https://cds.cern.ch/record/1798457">CERN</a>)</figcaption></figure><p>Franco Bonaudi became involved in the great CERN adventure before the Organization was even founded. Given the responsibility of coordinating the first accelerator project, the Synchrocyclotron, he supervised the construction work. He went on to take part in the construction and operation of many accelerators at CERN and held the post of Director of Accelerators from 1976 to 1978.</p> <p>“In 1951, I was at the Turin Polytechnic when Edoardo Amaldi, one of CERN’s founding fathers, contacted the teaching staff to find out whether they knew of any young scientists who would be interested in taking part in the construction of a particle physics laboratory. I went to Rome to meet Giuseppe Fidecaro, Amaldi’s right-hand man, and it was there that I learnt that the idea was to build a synchrocyclotron. I agreed to participate and left for Liverpool, where I took part in the design studies.</p> <p>We worked in various European institutes for two years without even knowing where the machine was going to be built. We all started together in huts at Geneva airport in 1954. At that time, the Laboratory consisted of about 150 people of all nationalities. We quickly got used to working together and communicated with each other in bad English. We felt rather lonely, being new to the area, and so we became very close. I remember that the CERN phone directory contained everyone’s home number. Some real friendships were formed.</p> <figure role="group" class="align-left"><img alt="Bikes and a truck with a giant magnet travelling on a country road" data-entity-type="file" data-entity-uuid="533741b8-02d1-4e94-a92c-ce3d4b5da116" height="auto" src="/sites/default/files/inline-images/katebrad/5661005-A4-at-144-dpi-crop.jpg" width="1568" loading="lazy" /><figcaption>Transport of a Synchrocyclotron coil through the village of Meyrin in May 1956. (Image: <a href="https://cds.cern.ch/record/795462">CERN</a>)</figcaption></figure><p>My colleague Joop Vermeulen and I were the first to move onto the site of the new Laboratory. We erected a hut with windows, right in the middle of the worksite, and stayed there for two years. The cyclotron was completed in only three years, which was fantastic. We had great enthusiasm and were often required to be inventive. I remember, for example, that we had no heating during our first winter at the SC. We managed to borrow some cast-iron resistors from the Geneva trams. Thanks to this improvised electric heating system, we were able to keep warm all winter. I could tell you dozens of stories like that …”</p> <p>----</p> <p><em>This interview is adapted from the 2004 book “Infinitely CERN”, published to celebrate CERN’s 50th anniversary. Franco Bonaudi <a href="https://cds.cern.ch/record/1156865?ln=en">passed away</a> in 2008 at the age of 80, read more about him in the <a href="https://cerncourier.com/a/franco-bonaudi-wise-spirit-of-the-early-cern/">CERN Courier</a>.</em></p> <figure class="cds-video" id="CERN-VIDEO-2014-006-001"><div style="position: relative; padding-top: 56.25%; max-width:1080px; max-height:1920px;"><iframe allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen="" frameborder="0" height="1920px" src="https://videos.cern.ch/video/CERN-VIDEO-2014-006-001" style="position:absolute; top:0; left:0; width:100%; height:100%; max-width:1080px; max-height:1920px;" width="1080px"></iframe></div> <figcaption>Archive footage from Cine Journal Suisse showing the transportation of a Synchrocyclotron magnet coil on its way from Basel to CERN, passing through the narrow streets of Swiss villages Morat and Coppet. Transportation of the magnet coils took place in 1955 and 1956.<span> (Video: CERN)</span></figcaption></figure><p> </p> </div> </div> </div> </div> </div> </div> </div> <div class="field--item"> Franco Bonaudi, one of the pioneers of CERN&#039;s accelerators, looks back at the Laboratory&#039;s early years, during which everything had yet to be invented </div> </div> </div> Tue, 30 Jan 2024 14:29:35 +0000 katebrad 189327 at https://home.cern CERN70: Foundations for European science https://home.cern/news/series/cern70/cern70-foundations-european-science <div class="layout layout__region featured-story-page-node-layout-content"> <div class="field--items"> <div class="field--item"> <div class="component-row component-row__display__fluid section-navigation component-row__has-header effect_none is_half_height"> <div class="background__veil"></div> <div class="background-component background__image" style="background:url(&#039;/sites/default/files/2024-01/5210004-A4-at-144-dpi_0.jpg&#039;) no-repeat center top / cover; height: 100%;"></div> <div class="component-row__row"> <div class="component-row__column component-row__center section-has-no-column col-md-12 col-sm-12 col-xs-12"> <div class="box-effects-wrapper "> <div class="cern-component-header-blocks component-header"> <div id="header-blocks--8" class="owl-carousel owl-theme component-header__carousel header-carousel"> <div class="header-block"> <div class="header-block__title"> <h3 class="header-block__name" > <span>CERN70: Foundations for European science</span> <span class="header-block__name__underline"></span> </h3> <span class="header-block__subhead" ><p class="text-align-center">18 January 2024 · <i>Voir en <a href="/fr/news/series/cern70/foundations-european-science">français</a></i></p> <hr /><p class="text-align-center"><strong>Part 1</strong> of the <strong><a href="/news/series/cern-70">CERN70</a></strong> feature series<br /><br /><strong>François de Rose</strong>, a French diplomat, was involved in the creation of CERN<br /> In 2004, he still remembered the first discussions that ultimately led to the birth of the Organization</p> </span> </div> </div> </div> </div> <a class="endof-cern-header-blocks"></a> </div> </div> </div> </div> </div> <div class="field--item"> <div class="component-row component-row__display__centered section-navigation effect_none"> <div class="component-row__row"> <div class="component-row__column component-row__center section-has-no-column col-md-12 col-sm-12 col-xs-12"> <div class="box-effects-wrapper "> <div class="component-margin component-margin-medium" ></div> <div class="text-component text-component-page clearfix"> <div class="text-component-text cern_full_html"> <figure role="group" class="align-right"><img alt="The Third Session of the provisional CERN Council in Amsterdam on 4 October 1952" data-entity-type="file" data-entity-uuid="6ea16256-cfeb-4e16-af0d-e516f0ae1890" height="auto" src="/sites/default/files/inline-images/katebrad/5210004-A4-at-144-dpi.jpg" width="1387" loading="lazy" /><figcaption>Many of CERN's founders gathered for the third session of the provisional CERN Council in Amsterdam on 4 October 1952. At this session, Geneva was chosen as the site for the Laboratory and it was decided to build a 25-30 GeV Proton Synchrotron. (Image: <a href="http://cdsweb.cern.ch/record/39071">CERN</a>)</figcaption></figure><p>In the aftermath of the Second World War, a handful of visionary scientists imagined how to revive science in Europe. By pooling the resources of several countries, they hoped to equip Europe with accelerators similar to those being built in the United States, and thus stem the brain drain. The idea of creating a European atomic physics laboratory took shape. After months of negotiations, the UNESCO Intergovernmental Conference in 1951 adopted the first resolution to create a European Council for Nuclear Research (CERN).</p> <p>The CERN Convention, drawn up in 1953, was gradually ratified by the 12 founding Member States: Belgium, Denmark, France, the Federal Republic of Germany, Greece, Italy, the Netherlands, Norway, Sweden, Switzerland, the United Kingdom and Yugoslavia.</p> <p>On 29 September 1954, the European Organization for Nuclear Research officially came into being. The provisional Council was dissolved, but the acronym remained.</p> </div> </div> <div class="text-component text-component-page clearfix"> <h2 class="text-component-title"> Recollections </h2> <div class="text-component-text cern_full_html"> <blockquote>CERN is one of the achievements with which I am the most proud to have been associated … it is such a noble cause.<br /><strong><em>François de Rose</em></strong></blockquote> <figure role="group" class="align-right"><img alt="François de Rose next to CERN Director-General John Adams in 1960" data-entity-type="file" data-entity-uuid="04cb87bc-727e-4b88-b05f-be299d68de11" height="auto" src="/sites/default/files/inline-images/katebrad/6002058-crop.jpg" width="1440" loading="lazy" /><figcaption>François de Rose (left) with CERN Director-General John Adams at the inauguration of the PS in 1960. (Image: <a href="http://cds.cern.ch/record/39962">CERN</a>)<br />  </figcaption></figure><p>François de Rose, a French diplomat, was involved in the creation of CERN from the very beginning. He went on to hold office as President of the CERN Council from 1958 to 1960, during which time he helped to prepare the Laboratory's extension into French territory. Interviewed in 2004, he had vivid memories of the initial discussions that led to the birth of the Organization.</p> <p>"CERN is one of the achievements with which I am the most proud to have been associated … it is such a noble cause.</p> <p>The first steps towards CERN’s creation were taken in the United States between 1947 and 1949. At that time I was the French representative to the United Nations International Atomic Energy Commission, which comprised both diplomats and scientists. It was there that I met Robert Oppenheimer, with whom I struck up a friendship. Like many American scientists, he had been very much influenced by European science, having worked in Niels Bohr’s group in particular. During one of our conversations he said more or less the following: “We have learnt all we know in Europe. But in the future, fundamental physics research is going to require substantial resources which will be beyond the means of individual European countries. You will need to pool your efforts to build these big machines that are going to be needed. It would be unhealthy if the Europeans were obliged to go the United States or the Soviet Union to conduct their fundamental research.” The idea fascinated me and I arranged for him to meet the French scientific advisers from my Commission, Pierre Auger, Francis Perrin, Lew Kowarski, and Bertrand Goldschmidt.</p> <figure role="group" class="align-left"><img alt="Signed CERN Convention" data-entity-type="file" data-entity-uuid="74470161-0ff1-4d62-8c4c-8544e8087b69" height="auto" src="/sites/default/files/inline-images/katebrad/5307006-A4-at-144-dpi.jpg" width="1129" loading="lazy" /><figcaption>At the sixth session of CERN's provisional Council, held in Paris in summer 1953, the Convention establishing the Organization was signed. It was ratified in the following months by the 12 founding Member States. (Image: <a href="https://cds.cern.ch/record/39554?ln=en">CERN</a>)</figcaption></figure><p>In 1949, when we returned to Paris, I went on a tour of European capitals with Francis Perrin to see what sort of reception Oppenheimer’s idea would be given. We were confronted with a lack of interest: the scientists were afraid that a big research centre would swallow all the available funds and soak up the resources of their own laboratories. They were wrong, however, because as soon as CERN started to request resources there was an increase in the funding allocated to research. What’s more, the governments had no idea of what it was all about: when they heard the words ‘atomic research’, they immediately thought of the atom bomb and were afraid that it would not go down well with the Americans. Last but not least, the fact that Frédéric Joliot Curie, an eminent member of the Communist Party, was in charge of the French Atomic Energy Commission caused the other European scientists to have cold feet. We therefore failed in our mission. However, the idea was now on the table and Isidor Rabi’s speech at the Florence General Conference secured the breakthrough we needed.</p> <p>CERN was created so that Europeans were not forced to go the United States. Today, Americans are coming to Europe to work on CERN’s machines, something which I don’t think Oppenheimer had anticipated. I find that an extraordinary turnaround.”</p> <p>----</p> <p><em>This interview is adapted from the 2004 book “Infinitely CERN”, published to celebrate CERN’s 50th anniversary. François de Rose <a href="/news/obituary/cern/francois-de-rose-1910-2014">passed away</a> in 2014 at the age of 103, read more about him in the <a href="https://cerncourier.com/a/franois-de-rose-strategist-and-visionary/">CERN Courier</a>.</em></p> </div> </div> </div> </div> </div> </div> </div> <div class="field--item"> François de Rose, a French diplomat, was involved in the creation of CERN. In 2004, he still remembered the first discussions that ultimately led to the birth of the Organization </div> </div> </div> Wed, 17 Jan 2024 07:38:22 +0000 katebrad 189241 at https://home.cern A break that revitalises you? https://home.cern/news/series/work-well-feel-well/break-revitalises-you <div class="layout layout__region featured-story-page-node-layout-content"> <div class="field--items"> <div class="field--item"> <div class="component-row component-row__display__fluid section-navigation component-row__has-header effect_none is_half_height"> <div class="background__veil"></div> <div class="background-component background__image" style="background:url(&#039;/sites/default/files/2023-12/WWFW-2-min-crop.jpg&#039;) no-repeat center top / cover; height: 100%;"></div> <div class="component-row__row"> <div class="component-row__column component-row__center section-has-no-column col-md-12 col-sm-12 col-xs-12"> <div class="box-effects-wrapper "> <div class="cern-component-header-blocks component-header"> <div id="header-blocks--10" class="owl-carousel owl-theme component-header__carousel header-carousel"> <div class="header-block"> <div class="header-block__title"> <h3 class="header-block__name" > <span>A break that revitalises you? </span> <span class="header-block__name__underline"></span> </h3> <span class="header-block__subhead" ><p class="text-align-center">By: <a href="/authors/hr-department"><span class="cern-tag">HR department</span></a></p> <p class="text-align-center">18 December, 2023 · <i>Voir en <a href="/fr/news/series/work-well-feel-well/break-revitalises-you">français</a></i></p> <hr /><p class="text-align-center"><strong>Part 2</strong> of the <strong><a href="/news/series/work-well-feel-well/">Work Well Feel Well</a> series</strong> looks at <strong>why taking a break is so important</strong></p> </span> </div> </div> </div> </div> <a class="endof-cern-header-blocks"></a> </div> </div> </div> </div> </div> <div class="field--item"> <div class="component-row component-row__display__centered section-navigation effect_none"> <div class="component-row__row"> <div class="component-row__column component-row__center section-has-no-column col-md-12 col-sm-12 col-xs-12"> <div class="box-effects-wrapper "> <div class="text-component text-component-page clearfix"> <h2 class="text-component-title"> Time to take a break </h2> <div class="text-component-text cern_full_html"> <p><img alt="Graphic of 2nd part in 12-part series" data-entity-type="file" data-entity-uuid="408b24c2-5ca8-45b1-b096-1d2608334fcb" height="auto" src="/sites/default/files/inline-images/katebrad/WWFW_2_Pauses-1440.png" class="align-right" width="691" loading="lazy" /></p> <p>As one year ends and another begins, the two-week CERN closure can give us time to rest. <strong>Taking a break is necessary</strong>, not only at the end of the year, but <strong>within each working day</strong>. We can all make it a New Year’s resolution in 2024 to find time to take a break.</p> <p>Why? Allowing ourselves to rest aids our <strong>physical and mental wellbeing</strong>. We return to a task with <strong>renewed energy and perspective</strong>, helping to <strong>increase our efficiency</strong> in the short and medium term.</p> <figure role="group" class="align-left"><img alt="Aerial photo of CERN restaurant 1's terrace with people sitting at tables" data-entity-type="file" data-entity-uuid="a0e72750-632a-45f7-9703-b548ceb5b591" height="auto" src="/sites/default/files/inline-images/katebrad/2012-10-16CERN_Resto1-1440-min.jpg" width="1440" loading="lazy" /><figcaption>Reclaim the lunch break! This official break restores vitality, improves wellbeing and reconnects us with those around us and with ourselves. (Image: Christoph Balle/CERN)</figcaption></figure><p> </p> <p> </p> <p> </p> <p>Our workdays have an <strong>official break of one hour for lunch</strong>. Let’s <strong>reclaim it</strong>. It is an official time where we can <strong>disconnect from work</strong> and <strong>reconnect with colleagues</strong>. The pause <strong>restores vitality</strong> and improves our wellbeing. We can also add <strong>micro-breaks</strong> into our days, helping to keep a healthy distance from ongoing tasks; for example taking our eyes away from the computer screen for a few minutes.</p> <p>Some breaks are almost invisible: a long deep breath before continuing to work. Other breaks involve a pause in concentration, setting aside a complex task to work on a simpler one. <strong>A break doesn’t always mean doing nothing</strong>; it can also involve doing something else. In fact, some of us need to do something to clear our minds.</p> <figure class="cds-image align-right" id="CERN-GE-5804001-01"><a href="//cds.cern.ch/images/CERN-GE-5804001-01" title="View on CDS"><img alt="CERN50" src="//cds.cern.ch/images/CERN-GE-5804001-01/file?size=medium" /></a> <figcaption>CERN70: Some of CERN’s first personnel take a break in 1958, with the Salève mountain in the background.<span> (Image: CERN)</span></figcaption></figure><p> </p> <h3>A break that revitalises you?</h3> <p>We’ve all taken breaks that didn’t help to recover our strength. Even worse, we may return to work more tired than before. The best way to see if the break has been beneficial is to see how we feel when we come back.</p> <p><strong>A real break replenishes our energy </strong>and<strong> increases our efficiency</strong>. This means <strong>quietening our minds</strong>, changing our ideas and stepping back from current activities. It’s all about <strong>responding to our own needs</strong>: recharging our batteries, exercising, eating and drinking properly. It’s also knowing how to recreate internal availability, often lost among unfinished tasks and the demanding rhythm of work.</p> <p>Offering ourselves a beneficial break, be it official or regular micro-breaks, involves <strong>working out what we really need and allowing ourselves that time</strong>.</p> </div> </div> <div class="text-component text-component-page clearfix"> <h2 class="text-component-title"> Take action </h2> <div class="text-component-text cern_full_html"> <p>As part of the “Efficiency and caring at work” campaign, the <a href="https://hr.web.cern.ch/work-well-feel-well">Work Well Feel Well website</a> now offers useful resources that can be downloaded, including self-reflection exercises and sleep advice.</p> <ul><li>The recordings of the <a href="https://home.cern/news/announcement/cern/join-three-interactive-sessions-effective-tools-better-deal-stress">recent talks</a> by the CERN Medical Service and psychologists on the topics of <a>“</a><a href="https://cds.cern.ch/record/2875443">Flash disconnect</a>” and “<a href="https://cds.cern.ch/record/2876374">Cardiac coherence</a>” provide practical advice and exercises to take a break during the working day.</li> <li>The <a href="https://mediastream.cern.ch/MediaArchive/Video/Public2/weblecture-player/index.html?year=2019&amp;lecture=852676c2">recording</a> of the 2019 CERN talk “<a href="https://indico.cern.ch/event/852676/">Sleep: The Wake Up Call</a>” by Vicki Culpin highlights the importance of resting.</li> <li>For those who prefer a break to be a chance to do something else, the Staff Association provides a list of wide-ranging <a href="https://staff-association.web.cern.ch/unite/clubs">clubs</a>.</li> </ul><p>This is the second of a 12-part <a href="https://home.cern/news/series/work-well-feel-well/">Work Well Feel Well</a> series, with articles to be published every two months.</p> </div> </div> </div> </div> </div> </div> </div> <div class="field--item"> Part 2 of the Work Well Feel Well series looks at why taking a break is so important </div> </div> </div> Thu, 14 Dec 2023 12:57:09 +0000 katebrad 189128 at https://home.cern No, no… it’s OK… https://home.cern/news/series/work-well-feel-well/no-no-its-ok <div class="layout layout__region featured-story-page-node-layout-content"> <div class="field--items"> <div class="field--item"> <div class="component-row component-row__display__fluid section-navigation component-row__has-header effect_none is_half_height"> <div class="background__veil"></div> <div class="background-component background__image" style="background:url(&#039;/sites/default/files/2023-10/WWFW-1_0.jpg&#039;) no-repeat center top / cover; height: 100%;"></div> <div class="component-row__row"> <div class="component-row__column component-row__center section-has-no-column col-md-12 col-sm-12 col-xs-12"> <div class="box-effects-wrapper "> <div class="cern-component-header-blocks component-header"> <div id="header-blocks--12" class="owl-carousel owl-theme component-header__carousel header-carousel"> <div class="header-block"> <div class="header-block__title"> <h3 class="header-block__name" > <span>No, no… it’s OK…</span> <span class="header-block__name__underline"></span> </h3> <span class="header-block__subhead" ><p class="text-align-center">By: <a href="/authors/hr-department"><span class="cern-tag">HR department</span></a></p> <p class="text-align-center">10 October, 2023 · <i>Voir en <a href="/fr/news/series/work-well-feel-well/no-no-its-ok">français</a></i></p> <hr /><p class="text-align-center"><strong>Part 1</strong> of the <strong><a href="/news/series/work-well-feel-well/">Work Well Feel Well</a> series</strong> looks at <strong>developing an awareness of health indicators</strong></p> </span> </div> </div> </div> </div> <a class="endof-cern-header-blocks"></a> </div> </div> </div> </div> </div> <div class="field--item"> <div class="component-row component-row__display__centered section-navigation effect_none"> <div class="component-row__row"> <div class="component-row__column component-row__center section-has-no-column col-md-12 col-sm-12 col-xs-12"> <div class="box-effects-wrapper "> <div class="text-component text-component-page clearfix"> <h2 class="text-component-title"> Developing an awareness of health indicators </h2> <div class="text-component-text cern_full_html"> <p><img alt="Graphic of the first in a 12-part series" data-entity-type="file" data-entity-uuid="60ef33b1-eb8e-473b-9fb7-5e404f02e45a" height="auto" src="/sites/default/files/inline-images/katebrad/WWFW_screen_1_Signes_0.jpeg" class="align-right" width="3840" loading="lazy" />While a <strong>healthy amount of stress</strong> can provide motivation and drive, when work commitments are high, stress can negatively impact our health. It's essential to put measures in place to <strong>protect our health</strong> from the <strong>harmful effects of chronic stress</strong>.</p> <p>In situations of chronic stress, we often convince ourselves that we can hold out a bit longer, without making any significant changes to our habits. Taking account of our own needs and limits can prove difficult. Sometimes we <strong>only become aware of our limits when they have been exceeded</strong> and it has become impossible to cope. This can manifest itself in extreme ways, either <strong>physically</strong> through illness, exhaustion, back pain and heart problems, or <strong>emotionally</strong> through anxiety, paranoia or burnout.</p> </div> </div> <div class="text-component text-component-page clearfix"> <h2 class="text-component-title"> Take action </h2> <div class="text-component-text cern_full_html"> <figure role="group" class="align-left"><a href="https://indico.cern.ch/event/1302707/"><img alt="Poster advertising burnout talk" data-entity-type="file" data-entity-uuid="d1d92029-349e-4934-ac53-ae190cdd04e6" height="auto" src="/sites/default/files/inline-images/katebrad/Micro-talk-burnout.png" width="4000" loading="lazy" /></a> <figcaption>The recording and self-assessment tools are now available <a href="https://indico.cern.ch/event/1302707/">here</a> (login required).</figcaption></figure><p> </p> <p>As part of the <strong>“Efficiency and caring at work” campaign</strong>, the <a href="https://hr.web.cern.ch/work-well-feel-well">Work Well Feel Well website</a> now offers <strong>useful resources</strong> that can be downloaded and completed to help to recognise and pay attention to health indicators at work.</p> <p>This can help to maintain a balance and ensure that the amount of stress experienced is healthy.</p> <p>The <strong>recording</strong> of the Micro-Talk from 6 October 2023 entitled <strong>“Preventing burn-out in a demanding professional context”</strong> is <strong>now available</strong>, alongside <strong>self-assessment tools <a href="https://indico.cern.ch/event/1302707/">here</a></strong> (login required), with the presentation in French and slides in English.</p> </div> </div> <div class="text-component text-component-page clearfix"> </div> <div class="text-component text-component-page clearfix"> <div class="text-component-text cern_full_html"> <p>In addition, in the light of <strong><a href="https://www.who.int/campaigns/world-mental-health-day">World Mental Health Day</a> on 10 October</strong>, CERN’s Medical Service and psychologists <a href="/news/announcement/cern/join-three-interactive-sessions-effective-tools-better-deal-stress">invite you</a> to <strong>three interactive sessions</strong> on <strong>11, 18 and 25 October </strong>to learn effective and useful tools to better deal with stress.</p> <p><a href="/news/announcement/cern/join-three-interactive-sessions-effective-tools-better-deal-stress"><img alt="Poster advertising 3 mental health talks" data-entity-type="file" data-entity-uuid="9af68e91-1c68-4548-adcd-d957a2766868" height="auto" src="/sites/default/files/inline-images/katebrad/Mental-health_0.jpg" width="1440" loading="lazy" /></a></p> <p>  </p> </div> </div> <div class="text-component text-component-page clearfix"> <div class="text-component-text cern_full_html"> <p>This is the <strong>first</strong> of a <strong>12-part <a href="/news/series/work-well-feel-well/">Work Well Feel Well</a> series</strong>, with articles to be published every two months. </p> </div> </div> </div> </div> </div> </div> </div> <div class="field--item"> Part 1 of the Work Well Feel Well series looks at developing an awareness of health indicators </div> </div> </div> Tue, 10 Oct 2023 08:33:12 +0000 katebrad 188773 at https://home.cern A ten-year journey through the quark–gluon plasma and beyond https://home.cern/news/series/feature/ten-year-journey-through-quark-gluon-plasma-and-beyond <div class="layout layout__region featured-story-page-node-layout-content"> <div class="field--items"> <div class="field--item"> <div class="component-row component-row__display__fluid section-navigation component-row__has-header effect_none is_full_height"> <div class="background__veil"></div> <div class="background-component background__cds_media" style="height: 100%;"> <figure class="cds-image" data-record-id="2727174" data-filename="202008-104_04" id="CERN-PHOTO-202008-104-64"> <a href="//cds.cern.ch/images/CERN-PHOTO-202008-104-64" title="View on CDS"> <img alt="Lowering and insertion of the ALICE TPC" src="//cds.cern.ch/images/CERN-PHOTO-202008-104-64/file?size=large"/> </a> <figcaption> The refurbished detector, the Time Projection Chamber (TPC), was lowered into the ALICE cavern and installed in the experiment in August. <span> (Image: CERN)</span> </figcaption> </figure> </div> <div class="component-row__row"> <div class="component-row__column component-row__center section-has-no-column col-md-12 col-sm-12 col-xs-12"> <div class="box-effects-wrapper "> <div class="cern-component-header-blocks component-header"> <div id="header-blocks--2" class="owl-carousel owl-theme component-header__carousel header-carousel"> <div class="header-block"> <div class="header-block__title"> <h3 class="header-block__name" > <span>A ten-year journey through the quark–gluon plasma and beyond</span> <span class="header-block__name__underline"></span> </h3> <span class="header-block__subhead" ><p class="text-align-center">By: <a href="/authors/Alice-collaboration"><span class="cern-tag">ALICE collaboration</span></a></p> <p class="text-align-center">9 November, 2022 · <em>Voir en <a href="https://home.cern/fr/news/series/feature/ten-year-journey-through-quark-gluon-plasma-and-beyond">français</a></em></p> <hr /><p class="text-align-center">The ALICE collaboration takes stock of its first decade of quantum chromodynamics studies at the Large Hadron Collider</p> </span> </div> </div> </div> <span class="component-header__scroll"></span> </div> <a class="endof-cern-header-blocks"></a> </div> </div> </div> </div> </div> <div class="field--item"> <div class="component-row component-row__display__centered section-navigation effect_none"> <div class="component-row__row"> <div class="component-row__column component-row__center section-has-no-column col-md-12 col-sm-12 col-xs-12"> <div class="box-effects-wrapper "> <div class="text-component text-component-page clearfix"> <div class="text-component-text cern_full_html"> <p> </p> <p>Quantum chromodynamics (QCD) is one of the pillars of the <a href="/science/physics/standard-model">Standard Model</a> of particle physics. It describes the strong interaction – one of the four fundamental forces of nature. This force holds quarks and gluons – collectively known as partons – together in hadrons such as the proton, and protons and neutrons together in atomic nuclei. Two hallmarks of QCD are chiral symmetry breaking and asymptotic freedom. Chiral symmetry breaking explains how quarks generate the masses of hadrons and therefore the vast majority of visible mass in the universe. Asymptotic freedom states that the strong force between quarks and gluons decreases with increasing energy. The discovery of these two QCD effects garnered two Nobel prizes in physics, in <a href="https://www.nobelprize.org/prizes/physics/2008/summary/">2008</a> and <a href="https://www.nobelprize.org/prizes/physics/2004/summary/">2004</a>, respectively.</p> <p>High-energy collisions of lead nuclei at the <a href="/science/accelerators/large-hadron-collider">Large Hadron Collider</a> (LHC) explore QCD under the <a href="/news/series/lhc-physics-ten/recreating-big-bang-matter-earth">most extreme conditions on Earth</a>. These heavy-ion collisions recreate the quark–gluon plasma (QGP): the hottest and densest fluid ever studied in the laboratory. In contrast to normal nuclear matter, the QGP is a state where quarks and gluons are not confined inside hadrons. It is speculated that the universe was in a QGP state around one millionth of a second after the Big Bang.</p> <figure class="cds-image align-right" id="OPEN-PHO-EXP-2017-003-2"><a href="//cds.cern.ch/images/OPEN-PHO-EXP-2015-013-1 " title="View on CDS"><img alt="home.cern" src="//cds.cern.ch/images/OPEN-PHO-EXP-2015-013-1/file?size=large" /></a> <figcaption>Different views of a lead–lead collision event recorded by ALICE in 2015. (Image: CERN)</figcaption></figure><p>The <a href="/science/experiments/alice">ALICE</a> experiment was designed to study the QGP at LHC energies. It was operated during LHC Runs 1 and 2, and has carried out a broad range of measurements to characterise the QGP and to study several other aspects of the strong interaction. In a recent <a href="https://arxiv.org/abs/2211.04384">review</a>, highlights of which are described below, the ALICE collaboration takes stock of its first decade of QCD studies at the LHC.<a name="_bookmark0" id="_bookmark0"></a><a name="Probing_the_QGP_at_various_scales" id="Probing_the_QGP_at_various_scales"></a> The results from these studies include a suite of observables that reveal a complex evolution of the near-perfect QGP liquid that emerges in high-temperature QCD. ALICE measurements also demonstrate that charm quarks equilibrate extremely quickly within this liquid, and are able to regenerate QGP-melted “charmonium” particle states. ALICE has extensively mapped the QGP opaqueness with high-energy probes, and has directly observed the QCD dead-cone effect in proton–proton collisions. Surprising QGP-like signatures have also been observed in rare proton–proton and proton–lead collisions. Finally, ALICE measurements of interactions of produced hadrons have also revealed novel features that have broad implications for nuclear physics and astrophysics.</p> <h3><span style="font-size:22px;"><strong>Probing the QGP at various scales</strong></span></h3> <p>The QGP can be inspected with various levels of spatial and energy resolution (scale) using particles produced in heavy-ion collisions. High-energy quarks and gluons rapidly cross the QGP and interact with it as they evolve to a spray, or “jet”, of partons that eventually form hadrons, or “hadronise”. The interaction with the QGP reduces the jet’s energy and modifies its structure. A jet with an energy of 20 gigaelectronvolts, for example, can probe distances of 0.01 femtometres (1 femtometre is 10-15 metres), well below the roughly 10-fm size of the QGP. The jet modification, known as jet quenching, results in several distinct effects that ALICE has seen, including significant energy loss for <a href="https://cerncourier.com/a/alice-extends-quenching-studies-to-softer-jets/">jets</a> and a smaller energy loss for <a href="/news/news/physics/mass-matters-when-quarks-cross-quark-gluon-plasma">beauty quarks compared to charm quarks</a>.</p> <p>Lower-energy charm quarks also probe the QGP microscopically, and undergo Brownian motion – a random motion famously studied by Albert Einstein. ALICE has provided evidence that these lower-energy charm quarks participate in the thermalisation process by which the QGP reaches thermal equilibrium.</p> <p>Bound states of a heavy quark and its <a href="/science/physics/antimatter">antimatter</a> counterpart, or “quarkonia”, such as the J/ψ (charmonium) and Υ(1S) (bottomonium), are spatially extended particles and have sizes of about 0.2 fm. They therefore probe the QGP at larger scales compared to high-energy partons. The QGP interferes with the quark–antiquark force and suppresses quarkonia production. For quarkonia made up of charm quarks, ALICE has <a href="/news/news/physics/alice-explores-hidden-charm-quark-gluon-plasma">shown</a> that this suppression, which is stronger for more weakly bound states and thus “hierarchical”, is counterbalanced by charm quark–charm antiquark binding.</p> <figure class="cds-image align-left" id="CERN-VIDEO-2022-027-001"><div><iframe allowfullscreen="true" frameborder="0" height="450" src="//cds.cern.ch/video/CERN-VIDEO-2022-027-001" width="100%"></iframe></div> <figcaption><span>Animation of the quark–gluon plasma formed in collisions between heavy ions. (Video: CERN)</span></figcaption></figure><p>This recombination effect has been revealed for the first time at the LHC, where about one hundred charm quarks and antiquarks are produced in each head-on lead–lead collision. It constitutes a proof of quark deconfinement, as it implies that quarks can move freely over distances much larger than the hadron size. The hierarchical suppression can be explained assuming a QGP initial temperature roughly four times higher than the temperature at which the transition from ordinary hadronic matter to the QGP can occur (about two trillion degrees kelvin). An assessment of the QGP temperature was also obtained from the ALICE <a href="https://cerncourier.com/a/measurement-of-photons-stimulates-quest-for-qgp-temperature/">measurement</a> of photons that are radiated by the plasma during its expansion, yielding an average temperature from the entire temporal evolution of the collision of about twice the QGP transition temperature.</p> <p>Regarding the large-scale spatial evolution of the collision, ALICE has demonstrated that the QGP formed at LHC energies undergoes the most rapid expansion ever observed for a many-body system in the laboratory. The velocities of the particles that fly out of the QGP in a collective flow approach about 70% of the speed of light, and direction-dependent, or “anisotropic”, flow has been observed for almost all measured<a name="_bookmark4" id="_bookmark4"></a><a name="_bookmark5" id="_bookmark5"></a><a name="_bookmark6" id="_bookmark6"></a><a name="_bookmark7" id="_bookmark7"></a><a name="_bookmark8" id="_bookmark8"></a> hadron species, including light nuclei made of two or three protons and neutrons. Small variations seen in some specific flow patterns of hadrons with opposite electric charge are influenced by the huge electromagnetic fields produced in non-head-on heavy-ion collisions.</p> <p>Calculations based on hydrodynamics, originally conceived to describe liquids at a few hundred degrees kelvin, describe all of the flow observables, and demonstrate that this theoretical framework is a good description of many-body QCD interactions at trillions of degrees kelvin. Such a description is achieved with the crucial inclusion of a small QGP <a href="https://cerncourier.com/a/alice-explores-shear-viscosity-in-qcd-matter/">viscosity</a>, which is the smallest ever determined and thus establishes the QGP as the most perfect liquid.</p> <h3><span style="font-size:22px;"><strong>Hadron formation at high temperatures</strong></span></h3> <p>During the evolution of a heavy-ion collision, the QGP cools below the transition temperature and hadronises. After this hadronisation, the energy density may be large enough to allow for inelastic (hadron-creating) interactions, which change the medium’s “chemical” composition, in terms of particle species. Such interactions cease at the chemical freeze-out temperature, at which the particle composition is fixed. Elastic (non-hadron creating) interactions can still continue, and halt at the kinetic freeze-out temperature, at which the particle momenta are fixed.</p> <p>ALICE measurements of hadron production over all momenta have provided an extensive mapping of this hadron chemistry, and they show that hadrons with low momentum form by recombination of quarks from the QGP. Theoretical models, in which a hadron “gas” is in chemical equilibrium after the QGP phase, describe the relative abundances of hadron species using only two properties: the chemical freeze-out temperature, which is very close to the transition temperature predicted by QCD, and a “baryochemical potential” of zero within uncertainties, which demonstrates the matter–antimatter symmetry of the QGP produced at the LHC.</p> <p>In addition, ALICE investigations into the hadron-gas phase indicate that this phase is prolonged, and that the decoupling of particles from the expanding hadron gas is likely to be a continuous process.</p> <h3><span style="font-size:22px;"><strong>What are the limits of QGP formation?</strong></span></h3> <figure class="cds-image align-right" id="OPEN-PHO-EXP-2017-003-2"><a href="//cds.cern.ch/images/OPEN-PHO-EXP-2017-003-2" title="View on CDS"><img alt="home.cern" src="//cds.cern.ch/images/OPEN-PHO-EXP-2017-003-2/file?size=large" /></a> <figcaption>As the number of particles produced in proton–proton collisions increases (blue lines), the more particles containing at least one strange quark are measured (orange to red squares). (Image: CERN)</figcaption></figure><p>Studying how observables such as the particle production yields and multi-particle correlations change with multiplicity – the total number of particles produced – for proton–proton and proton–lead collisions provides a means to explore the thresholds required to form a QGP. A suite of ALICE measurements of high-multiplicity proton–proton and proton–lead collisions exhibit features similar to those observed in lead–lead collisions, where these are associated with QGP formation. The effects include the <a href="/news/news/experiments/new-alice-results-show-novel-phenomena-proton-collisions">enhancement of yields</a> of particles with strange quarks, the anisotropic flow determined from <a href="https://cerncourier.com/a/alice-and-atlas-find-intriguing-double-ridge-in-proton-lead-collisions/">particle correlations</a>, and the reduction of the yield of the feebly bound charmonium state ψ(2S) in proton–lead collisions. These observations were among the most surprising and unexpected from the first ten years of LHC running.</p> <p>The ability of the hydrodynamic framework and of theoretical models of a strongly interacting system to describe many of the observed features, even at low multiplicities, suggests that there is no apparent spatial limit to QGP formation. However, alternative models that do not require the presence of a QGP can also explain a limited number of these features. These models challenge the idea of QGP formation, and this might be supported by the fact that jet quenching has not been observed to date in the small proton–lead colliding system. However, such absence could also be caused by the small spatial extent of a possible QGP droplet, which would decrease the jet quenching. Therefore, the quest for the smallest collision system that leads to QGP formation remains open.</p> <h3><span style="font-size:22px;"><strong>Exploring few-body interactions</strong></span></h3> <p>ALICE investigations of few-body QCD interactions, such as those that take place in proton–proton collisions or in heavy-ion collisions in which the colliding nuclei only graze past each other, have provided a wide range of measurements. Examples include precise measurements <a href="/news/news/physics/alice-finds-charm-hadronisation-differs-lhc">showing</a> that in these collisions the formation of hadrons from charm quarks differs from expectations based on electron-collider measurements, and the first direct <a href="/news/news/physics/alice-makes-first-direct-observation-fundamental-effect-particle-physics">observation</a> of the dead-cone effect, which consists of a suppression of the gluons radiated by a massive quark in a forward cone around its direction of flight.</p> <p>Grazing collisions, known as ultra-peripheral collisions, provide a means of exploring the internal structure of nucleons (protons or neutrons) via the emission of a photon from one nucleus that interacts with the other nucleus. ALICE studies of these collisions show clear evidence that the internal structure of nucleons bound in a nucleus is different from that of free protons.</p> <p>The large data samples of proton–proton and proton–lead collisions recorded by ALICE have allowed studies of the strong interaction between protons and hyperons – unstable particles that contain strange quarks and may be present in the core of neutron stars. ALICE has <a href="/news/news/physics/alice-collaboration-opens-avenue-high-precision-studies-strong-force">shown</a> that the interactions between a proton and Lambda, Xi or Omega hyperon are attractive. These interactions may play a part in the stability of the observed large-mass neutron stars. In addition, ALICE <a href="/news/news/physics/alice-pins-down-hypermatter-properties">measurements</a> of the lifetime and binding energy of hypertriton – an unstable nucleus composed of a proton, a neutron and a Lambda – are the most accurate to date and shed light on the strong interaction that binds hypernuclei together.</p> <h3><span style="font-size:22px;"><strong>The present and future of ALICE</strong></span></h3> <p>After a major upgrade, the ALICE experiment started to record <a href="/news/news/cern/third-run-large-hadron-collider-has-successfully-started">Run 3</a> proton–proton collisions in July 2022. The next full-scale data-taking of lead–lead collisions is planned for 2023, with a proposed pilot run expected in late 2022. The upgraded detector will reconstruct particle trajectories much more precisely and record lead–lead collisions at a higher rate. With the resulting, much larger Run 3 and then Run 4 <a href="https://ep-news.web.cern.ch/content/alice-gears-towards-rich-run-3-qcd-programme">data sets</a>, rare probes of the QGP that were already used in the past decade, such as heavy quarks and jets, will become high-precision tools to study the QGP. ALICE will also continue to use the small colliding systems to investigate, among other things, the smallest QGP droplet that can be formed and the proton’s inner structure.</p> <p>Besides further smaller-scale but highly innovative upgrades for the next LHC long shutdown, the ALICE collaboration has prepared a proposal for a completely <a href="/news/news/physics/alice-3-workshop-towards-next-generation-heavy-ion-experiment-2030s">new detector</a> to be operated in the 2030s. The new detector will open up even more new avenues of exploration, including the study of correlations between charm particles, of chiral-symmetry restoration in the QGP, and of the time-evolution of the QGP temperature.</p> </div> </div> </div> </div> </div> </div> </div> </div> </div> Tue, 08 Nov 2022 13:52:16 +0000 abelchio 185773 at https://home.cern Higgs10: inventing the future of Higgs research https://home.cern/news/series/higgs10/higgs10-inventing-future-higgs-research <div class="layout layout__region featured-story-page-node-layout-content"> <div class="field--items"> <div class="field--item"> <div class="component-row component-row__display__fluid section-navigation component-row__has-header effect_none is_full_height"> <div class="background__veil"></div> <div class="background-component background__cds_media" style="height: 100%;"> <figure class="cds-image" data-record-id="1996997" data-filename="TUNNEL3D V2aCOMPO smooth panoramic montage" id="OPEN-PHO-ACCEL-2015-001-1"> <a href="//cds.cern.ch/images/OPEN-PHO-ACCEL-2015-001-1" title="View on CDS"> <img alt="3D dipole integration panoramic poster" src="//cds.cern.ch/images/OPEN-PHO-ACCEL-2015-001-1/file?size=large"/> </a> <figcaption> 3D dipole integration showing several parts with an interconnection open. Integration 3D du dipole et interconnection ouverte. <span> (Image: CERN)</span> </figcaption> </figure> </div> <div class="component-row__row"> <div class="component-row__column component-row__center section-has-no-column col-md-12 col-sm-12 col-xs-12"> <div class="box-effects-wrapper "> <div class="cern-component-header-blocks component-header"> <div id="header-blocks--4" class="owl-carousel owl-theme component-header__carousel header-carousel"> <div class="header-block"> <div class="header-block__title"> <h3 class="header-block__name" > <span>Higgs10: inventing the future of Higgs research</span> <span class="header-block__name__underline"></span> </h3> <span class="header-block__subhead" ><p class="text-align-center">By: <a href="/authors/matthew-mccullough"><span class="cern-tag">Matthew McCullough</span></a></p> <p class="text-align-center">10 August, 2022 · <i>Voir en <a href="/fr/news/series/higgs10/higgs10-inventing-future-higgs-research">français</a></i></p> <hr /><p class="text-align-center">In the final part of the <a href="/news/series/higgs10"><span class="cern-tag">Higgs10</span></a> series, history teaches us that those who explore relentlessly and fearlessly are often the ones rewarded with the greatest prize of all: the truth.</p> </span> </div> </div> </div> <span class="component-header__scroll"></span> </div> <a class="endof-cern-header-blocks"></a> </div> </div> </div> </div> </div> <div class="field--item"> <div class="component-row component-row__display__centered section-navigation effect_none"> <div class="component-row__row"> <div class="component-row__column component-row__center section-has-no-column col-md-12 col-sm-12 col-xs-12"> <div class="box-effects-wrapper "> <div class="text-component text-component-page clearfix"> <div class="text-component-text cern_full_html"> <p> </p> <p>In 1975, three CERN theorists, John Ellis, Mary K. Gaillard and Dimitri Nanopoulos, undertook the first comprehensive study of the collider phenomenology of the Higgs boson. Almost 40 years later, it was discovered at the LHC. Now, ten years on, might we have such long-term foresight in anticipating the varied paths that future Higgs research may follow?</p> <blockquote>On 4 July 2022, enjoying the many beautiful presentations at the Higgs@10 symposium, a phrase kept ringing in my ears: “Compatible with Standard Model (SM) predictions”. Alarm bells were ringing. Really? Are we sure? Whether or not the Higgs is SM-like is a question that will shape the experimental future of Higgs research.</blockquote> <p>We may quantify an answer through the language of effective field theory, which is a mathematical manifestation of the notion that the most effective way to describe an object depends on the length scale you’re viewing it from. To astronauts, Earth is very effectively described as a smooth sphere. For summer students hiking to Le Reculet, it is not. So, too, of the quantum world. Far from a neutral atom, it effectively appears as a point-like particle with some leftover multipolar interactions with photons. At shorter distances, getting in amongst the electrons, this description fails entirely.</p> <p>Ditto the Higgs. Whatever’s going on in there, at energies near enough to m_H, it is effectively described as a point particle with a handful of additional “operators”, which are essentially new particle interactions that aren’t contained in the SM (don’t feature on <em>that</em> mug or T-shirt) but do involve SM particles. By eye, the astronaut may be able to make out some features on Earth and surmise that there may be mountains, but they couldn’t actually estimate the students’ elevation gain. Similarly, the non-SM Higgs operators can capture the long-distance leftover effects of the microscopic innards of the Higgs, but not reveal their full glory in detail. If all of these extra operators vanish, the Higgs is SM-like. Let’s consider two hand-picked examples and investigate just how SM-like the Higgs is...</p> <h4>How “fuzzy” is it?</h4> <p>Is it point-like down to the smallest distance scales or is it, like the pion, made up of other as-yet-unidentified new particles? In the latter case, much as for the pions and their constituent quarks and gluons, directly observing the new stuff would require going to higher energies. Alternatively, it could be point-like but probing it closely may reveal the telltale clues of a cloud of new particles that it interacts with. For your interest, the operator that can capture these properties is written (∂μ|H|2)2. If it vanishes, the Higgs is entirely point-like. If not, it’s fuzzier than expected. How fuzzy is it? Present LHC Higgs coupling measurements suggest it is effectively point-like down to a length scale merely a factor three below the electroweak scale. It could still be very fuzzy indeed! As fuzzy as a pion. If so, hardly an SM-like Higgs! We must do better and, through much more precise coupling measurements at the 0.2% level, a future Higgs factory like the FCC-ee could determine if the Higgs is point-like as far down as the 6% level.</p> <h4>Does the Higgs find itself attractive?</h4> <p>Yes, according to the SM. New particles means new forces and so it follows that if the Higgs boson interacts with new heavy particles they will generate a new force between the Higgs and itself. The operator effectively capturing this is |H|6 and it literally shapes the way in which the Higgs field gave mass to particles during the very nascence of our universe! So, how SM-like is the Higgs self-attraction? With present experimental constraints, we know the Higgs self-attraction could be 530% stronger than the SM value (not merely self-attraction, more like outright vanity) or even −140% less (self-repulsive, more like). Hardly SM-like in either case! To have any idea of whether the self-attraction is SM-like, we must do a lot better. A future facility, such as the FCC-hh, CLIC or a muon collider, could probe the self-attraction at the much more precise 5% level.</p> <h4>Patience is a virtue; complacency is not</h4> <p>It is far too early to call time at the bar for the Higgs boson. Who knows, we may even be served with something completely unexpected, like a new window into the dark sector of the universe. Truly exploring all facets of the nature of the Higgs boson, understanding whether or not it is SM-like, will take time (measured in decades) and a lot of hard work. But it can and should be done. This is the experimental future of Higgs research that we look forward to.</p> <p>All that said, it’s no secret that many theorists expected the Higgs to be much less SM-like than it appears to be already. Heads duly scratched, a theoretical coup d’état is now silently under way. There were good reasons to expect something different: chiefly the hierarchy problem. This problem is not simply aesthetic. The SM breaks down at high energies, ultimately making pathological predictions, thus it can only be a long-distance effective field theory description of something else more fundamental. If, as was the case for pions, the Higgs mass is determined by the more fundamental parameters, then for the Higgs there is no mechanism to keep it lighter than the mass scale of the new particles in that theory. Yet colliders tell us there is a gap between the mass of the Higgs and that of those new particles. In the past, this motivated the discovery and development of new mechanisms to explain a light Higgs, such as the venerated low-scale supersymmetry, thus far a no-show at the LHC physics party, with its attendant non-SM-like Higgs.</p> <p>Rudely awoken by the deluge of exclusion plots, coffee reluctantly smelled, theorists have, in recent years, put forward what could well transpire to be revolutionary theoretical developments. The hierarchy problem hasn’t gone away and neither has the data, so the other foundational assumptions covertly injected into the old theories, often linked to symmetry or aesthetic principles such as simplicity or minimality, have been interrogated and found wanting. In response, intrepid new classes of theories have been developed that can address the hierarchy problem whilst being consistent with all those bothersome exclusion plots. They range from relatively modest conceptual tweaks of existing structures, to the abandonment of aesthetic principles, and then all the way out the other side to attempts to link the Higgs mass to the origins of the universe, cosmology, the nature of the Big Bang and, at an extreme, speculations about possible links between the Higgs mass and the existence of life itself. You name it, we’re boldly going.</p> <h4>It’s no <em>fait accompli</em></h4> <p>None of these ideas are as intoxicating as supersymmetry or as stupefying as extra dimensions, each leaving those who study them with more of a “watch this space” feeling than the “eureka” that Archimedes enjoyed. Variously, they’re not radical enough, too radical or simply not to taste. No Goldilocks moment just yet. However, in my view these issues are cause for hope. In similar moments in the past, we have been essentially on the right track, having to wait a little longer than expected for the confirming experimental data (top quark). At other times, the right ideas have been too radical for most to stomach in one sitting (quantum mechanics). Yet for others the correct approaches languished in relative obscurity far too long, simply for not being <em>à la mode</em> (quantum field theory). Look up the citation records of the original Brout-Englert, Higgs, Guralnik-Hagen-Kibble papers or Weinberg’s “A Model of Leptons”, all foundational to the physics of the Higgs boson, and you’ll see they are important cases in point that we would do well to remember. Nature made no promises that understanding the origins of the Higgs should have been easy, nor should it be in the future, but history teaches that those who explore relentlessly and fearlessly are often the ones rewarded with the greatest prize of all: the truth.</p> <h4>Where will all this go in coming years?</h4> <p>Will we be tenacious enough to build the accelerator, the detectors and the village it will take to measure the Higgs self-attraction or discover the fuzziness of the Higgs? Will some plucky theorists unlock the door to the fundamental theory beyond the SM? Will future phenomenologists lay the first foundational stones on the path to discovering it?</p> <p>As Dennis Gabor, the inventor of holography, put it: “The future cannot be predicted, but futures can be invented.”<br /> We’re working on it.</p> </div> </div> </div> </div> </div> </div> </div> <div class="field--item"> History teaches that those who explore relentlessly and fearlessly are often the ones rewarded with the greatest prize of all: the truth. </div> </div> </div> Fri, 19 Aug 2022 07:32:25 +0000 katebrad 185012 at https://home.cern Higgs10: Ten things we’ve learned about the Higgs boson in the past ten years https://home.cern/news/series/higgs10/higgs10-ten-things-weve-learned-about-higgs-boson-past-ten-years-0 <div class="layout layout__region featured-story-page-node-layout-content"> <div class="field--items"> <div class="field--item"> <div class="component-row component-row__display__fluid section-navigation component-row__has-header effect_none is_full_height"> <div class="background__veil"></div> <div class="background-component background__cds_media" style="height: 100%;"> <figure class="cds-image" data-record-id="2816153" data-filename="Screenshot%202022-07-19%20at%2015.31.24" id="CERN-HOMEWEB-PHO-2022-149-1"> <a href="//cds.cern.ch/images/CERN-HOMEWEB-PHO-2022-149-1" title="View on CDS"> <img alt="Higgs10 Bulletin article - 7" src="//cds.cern.ch/images/CERN-HOMEWEB-PHO-2022-149-1/file?size=large"/> </a> <figcaption> <span> (Image: CERN)</span> </figcaption> </figure> </div> <div class="component-row__row"> <div class="component-row__column component-row__center section-has-no-column col-md-12 col-sm-12 col-xs-12"> <div class="box-effects-wrapper "> <div class="cern-component-header-blocks component-header"> <div id="header-blocks--6" class="owl-carousel owl-theme component-header__carousel header-carousel"> <div class="header-block"> <div class="header-block__title"> <h3 class="header-block__name" > <span>Higgs10: Ten things we’ve learned about the Higgs boson in the past ten years </span> <span class="header-block__name__underline"></span> </h3> <span class="header-block__subhead" ><p class="text-align-center">By: <a href="/authors/monica-dunford"><span class="cern-tag">Monica Dunford</span></a>&amp; <a href="/authors/andre-david"><span class="cern-tag">Andre David</span></a></p> <p class="text-align-center">19 July, 2022 · <i>Voir en <a href="/fr/news/series/higgs10/higgs10-ten-things-weve-learned-about-higgs-boson-past-ten-years-0">français</a></i></p> <hr /><p class="text-align-center">In the seventh part of the <a href="/news/series/higgs10"><span class="cern-tag">Higgs10</span></a> series, we give an overview of ten years of Higgs boson research.</p> </span> </div> </div> </div> <span class="component-header__scroll"></span> </div> <a class="endof-cern-header-blocks"></a> </div> </div> </div> </div> </div> <div class="field--item"> <div class="component-row component-row__display__centered section-navigation effect_none"> <div class="component-row__row"> <div class="component-row__column component-row__center section-has-no-column col-md-12 col-sm-12 col-xs-12"> <div class="box-effects-wrapper "> <div class="text-component text-component-page clearfix"> <div class="text-component-text cern_full_html"> <p> </p> <p>Since its discovery in 2012, the Higgs boson has become one of the most powerful tools to probe our understanding of nature and, with that, examine some of the biggest open questions in physics today. But what have we physicists learned about the particle in the past ten years? </p> <p><strong>A scalar particle exists in nature</strong></p> <p>During the early hours of 4 July 2012, the foyer outside the main CERN lecture hall looked more like the lead-up to a rock concert than the main building of the world’s leading particle physics lab. Dozens of groggy-eyed students slowly rolled up their sleeping bags, stretching out after a long night on the hard floor. A line hundreds long snaked through the foyer, around the restaurant and out the door. The excitement in the line was pulsating – even though the odds of making it into the auditorium were small, just to be there was a thrill. We had found it. A scalar particle existed in nature and 4 July 2012 was its debut.</p> <p><strong>It’s heavy and short-lived</strong></p> <p>The first measurements of the new scalar particle, H(125), relied on two experimental channels: 4-lepton decays and 2-photon decays. Although these are not the most abundant decay channels, they are the best in determining the scalar particle’s mass. The measured mass of about 125 GeV is maximally interesting: it is much heavier than was expected for popular models of supersymmetry, it puts the universe in a precarious position between being stable and metastable, and it has a rich phenomenology. In contrast to its heavy mass, the particle’s lifetime is short; it is gone in 10<sup>-22</sup> of a second.</p> <p><strong>It has no electric charge and no spin</strong></p> <p>The discovery of the H(125) via its decay to two photons immediately established that the new particle had no electric charge and strongly disfavoured it to have spin of 1. The exact spin of the new particle can be probed by examining the angular distributions of the final-state products in decays to two protons, two W bosons and two Z bosons. The spin 0 hypothesis has held up against a myriad of other possible assignments.</p> <figure class="cds-image align-left" id="CERN-HOMEWEB-PHO-2022-149-2"><a href="//cds.cern.ch/images/CERN-HOMEWEB-PHO-2022-149-2" title="View on CDS"><img alt="home.cern,Life at CERN" src="//cds.cern.ch/images/CERN-HOMEWEB-PHO-2022-149-2/file?size=large" /></a> <figcaption>Measurements of the interaction strength between the H(125) and some of the Standard Model particles. The red line represents the Standard Model expectation. Recent progress has increased the reach to second generations fermions, like the muon, and first results concerning charm quarks.<span> (Image: ATLAS)</span></figcaption></figure><p><strong>It interacts with other bosons</strong></p> <p>How the new boson interacts with other particles can be probed in both how it decays and how it is produced. With its discovery via decays to two photons and two Z bosons, it was readily concluded that the H(125) particle couples to bosons (in the case of photons, indirectly). This was further reaffirmed with measurements of decays to two W bosons. Furthermore, the production of the H(125) through couplings to bosons is measured when two vector bosons (force carriers such as W and Z bosons) fuse to produce the scalar or when the scalar radiates from a heavy boson (so-called V+H production).</p> <p><strong>It interacts with fermions</strong></p> <p>The Standard Model (SM) predicts that the strength of the coupling between the H(125) and other particles is proportional to their masses. Studying fermions tests these couplings over three fermion generations spanning three orders of magnitude of masses. For the heaviest fermions, all couplings have been measured – to top quarks (via measurements of ttH production), to beauty quarks and to tau leptons. Now, the experimental challenge lies in reaching the second generation, whose coupling with the Higgs boson is weaker. First evidence of decays to muons are emerging and both the ATLAS and CMS experiments are homing in on decays to charm quarks. </p> <p><strong>It could be a portal for dark matter</strong></p> <p>If dark matter consists of elementary particle(s), the SM simply does not predict any of them. If the H(125) and dark matter particles interact in nature, one possible signature is that of “invisible” Higgs boson decays. Such searches limit these decays to be lower than 15% and, consequently, set limits on interactions between this Higgs boson and possible dark matter particles and on the models that predict them. The SM predicts only a diminutive branching fraction of 0.1% – to four neutrinos. </p> <figure class="cds-image align-right" id="CERN-HOMEWEB-PHO-2022-149-3"><a href="//cds.cern.ch/images/CERN-HOMEWEB-PHO-2022-149-3" title="View on CDS"><img alt="home.cern,Life at CERN" src="//cds.cern.ch/images/CERN-HOMEWEB-PHO-2022-149-3/file?size=large" /></a> <figcaption>Limits on Higgs boson pair production, a process that is sensitive to the Higgs boson self-interaction and the shape of the Higgs potential. Results are presented as a function of time along with projections for the full HL-LHC dataset that should provide enough sensitivity to challenge the SM prediction (red horizontal line).<span> (Image: CMS)</span></figcaption></figure><p><strong>It may touch the structure of the universe</strong></p> <p>The inclusion of the Brout-Englert-Higgs mechanism in the SM leads to precise predictions of how the universe evolved during one of its earliest stages, the electroweak epoch. A scalar field can influence several aspects of cosmology and even play a role in the observed matter–antimatter asymmetry in the universe. Depending on the shape of the vacuum potential, the universe could be metastable and decay, and one way to probe this shape is to measure the different ways in which the H(125) interacts with itself. One of the signatures that can be used to access this self-interaction is the production of Higgs boson pairs. While existing analyses of LHC data have already started to exclude some non-SM alternatives, more data and future accelerators – like Higgs factories – will allow us to explore this critical area.</p> <p><strong>It seems to be a lone child</strong></p> <p>The SM is minimalistic as far as scalars are concerned: it predicts one single elementary scalar particle, with distinct types of interactions. In straightforward extensions to the minimal SM, more than one Higgs boson is predicted, resulting in different sets of interactions. Therefore, a vigorous programme of searches for other Higgs bosons – lighter and heavier, neutral and charged (and doubly charged) – has been undertaken. With other possibilities being strongly reduced, H(125) is presently the only scalar we know of in nature.</p> <p><strong>It’s a new player in the team pushing past the SM</strong></p> <p>This Higgs boson is the newest player joining the team of particles that we use to understand the nature of the universe. Matter–antimatter asymmetry, dark matter, unification of all forces; these are some of the questions where a coherent and precise exploration of the properties of particles like the Z and W bosons, the beauty and top quarks and now the H(125), probe energy regimes far beyond those directly accessible at colliders. One possibility is to extend the SM with generic interactions that represent the effect of particles and interactions beyond the direct reach of present colliders. Making use of all the information from H(125) and its team members in a consistent fashion may point us in the direction of the next standard model.</p> <p><strong>It’s just the beginning</strong></p> <p>While we have established several properties and interactions of the H(125), much remains to be learned about this Higgs boson. Far from just being the last prediction from the SM, the discovery of the H(125) and its singular scalar quality provides an important instrument to further our understanding of nature at its deepest. Is there really only one Higgs boson in nature? Do its properties differ from the SM predictions? Can it show us what is beyond the electroweak scale? Might it interact with dark matter particles? Will we be able to use it to measure the shape of the vacuum potential of the universe?</p> <p>Ten years ago, before the discovery of this formidable tool, these questions were beyond our reach. The H(125) has opened new doors, inviting us to walk through.</p> </div> </div> </div> </div> </div> </div> </div> <div class="field--item"> Since its discovery in 2012, the Higgs boson has become one of the most powerful tools to probe our understanding of nature and, with that, examine some of the biggest open questions in physics today. </div> </div> </div> Wed, 27 Jul 2022 09:18:30 +0000 thortala 184435 at https://home.cern