Experimental Seminars in Particle Physics

High-precision measurement of the W boson mass at CMS

by Josh Bendavid (Massachusetts Inst. of Technology (US))

Europe/Zurich
Aula Marchetti

Aula Marchetti

Description

The CMS collaboration recently published a new measurement of the mass of the W boson to be 80360.2 ± 9.9 MeV, in strong agreement with the Standard Model of particle physics, by using data collected in 2016 at the proton-proton collision energy of 13 TeV at the Large Hadron Collider.
The W boson mass is measured using a sample of W→μν events via a highly granular maximum likelihood fit to the kinematical distributions of the daughter muons, separated by electric charge. The significant in-situ constraints of theoretical inputs and their corresponding uncertainties provided by this novel approach, together with an accurate determination of the experimental effects, allowed to reach yhis unprecedented precision.