23 Jun/22
11:00 - 12:00 (Europe/Zurich)

Measuring MW at the LHC


4/3-006 at CERN


The measurement of the W boson mass is of high relevance to the particle physics community due to its direct relationship with other   Electroweak observables and has been strongly spotlighted after the  recent CDF-II result. The tension between the CDF-II result and other  experiments urge a better understanding of the W boson mass  determination at hadron colliders, calling for new measurements with  increasing precision. Determining the mass of the W boson is a  challenging endeavour due to the high precision that must be achieved,  of the order of 10^-4, which enforces a careful treatment of the physics  modelling as well as the alignment, calibration and simulation of the  detectors. The different conditions and designs of the LHC experiments  encourage adopting diverse strategies at some steps of the W boson mass  measurement. At the LHC, both ATLAS and LHCb collaborations have measured this observable in complementary kinematic regimes, and it is 
foreseen that the CMS collaboration will contribute in the near future. The current goal of these three LHC experiments is to achieve a  sensitivity similar to that of the current SM prediction. With the  analysis of the data samples collected in the Run 1 and Run 2 of the  LHC, the ATLAS, CMS and LHCb collaborations will help to clarify the  current picture on the W boson mass, shedding light on the global fits  to electroweak observables and the recent CDF-II measurement.

Lorenzo - Bio

Lorenzo Bianchini joined the CMS experiment in 2009. He got his PhD from Ecole Polytechnique in 2012 with a thesis on a search for Higgs bosons decaying to tau leptons. Then, he joined the ETH group as a postdoc, where he carried out the first search for ttH events using a matrix-element method. He continued working on the extraction of ttH and VH signals in the bb decay channel until their observations in CMS. In 2017 he joined the INFN Pisa group as staff researcher and started working on the measurement of the W boson mass with CMS. Since 2021, he is Associate Professor at University of Pisa, where he is pursuing his research work on mW with CMS as principal investigator of the ERC Consolidator grant "ASYMOW”.

Miguel - Bio

Miguel Ramos Pernas joined the LHCb experiment in 2014 to start working in CPV in b hadron decays at the University of Santiago de Compostela. In 2016 he started working on strange decays in the same institute, finalizing his thesis in 2020 with the search for the KS0 -> mu+ mu- decay as the main topic of his work. Afterwards he joined the LHCb team at the university of Warwick, where he took part of the W mass measurement at LHCb using 2016 data and where keeps working in order to make the measurement using the full Run 2 data sample. Through the years he has also played an important role in the construction and maintenance of the High Level Trigger of the LHCb experiment and contributed to the development of Real Time Analysis strategies and tools for the Run 3 of the LHC.

Stefano - Bio

Stefano is an experimental physicist at CERN working on the ATLAS  experiment. His research has focused on precision measurements of  Drell-Yan and top quark processes, and on the alignment of the ATLAS  Inner Detector. He is member of the xFitter collaboration for QCD  analysis of the parton disribution functions, and main author of the  DYTurbo program for fast predictions of the Drell-Yan process. He has  recently finished his term as ATLAS W,Z physics subgroup convener.  Stefano's main contribution to the ATLAS W-boson mass measurement was  the physics modelling.