Dear all, This is a reminder of the IIHE seminar tomorrow Friday 25 October: *    "High-precision measurement of the W boson mass at the CMS experiment" *by Dr. Jan Eysermans (MIT) The agenda can be found here: https://indico.iihe.ac.be/event/2054/ The seminar will take place at 14:30 in the Sacton seminar room (G.1.03). Please find the abstract and short bio below. Best regards, Gerrit *Abstract:* The W boson mass is measured using proton-proton collision data with an integrated luminosity of 16.8 fb⁻¹, collected by the CMS experiment in 2016. The mass is extracted through a fit to a highly granular two-dimensional distribution of transverse momentum (pT) and pseudorapidity (η) in a sample of W→μν decays, categorized by charge. This novel approach, which incorporates significant in-situ constraints on theoretical inputs and their associated uncertainties, along with precise determinations of experimental effects, yields a highly accurate W boson mass measurement of 80,360.2 ± 9.9 MeV, consistent with the Standard Model prediction. *Short Bio:* Jan Eysermans graduated in Physics from Ghent University in Belgium and completed his PhD at Benemérita Universidad Autónoma de Puebla in Mexico, where he worked on searching for new signatures beyond the Standard Model in the Higgs sector, especially focusing on charged Higgs bosons. He also served as the deputy technical coordinator for the CMS Resistive Plate Chambers subdetector, studied irradiation effects on RPC detectors, and contributed to Phase-2 upgrades. After working at SCK CEN as a project manager for nuclear fuel tests, Jan joined MIT as a postdoc at the CMS experiment, working on measuring the W boson mass.