About
In the Standard Model, the Z boson acquires its mass of around 91 GeV through its gauge interaction with the vacuum energy of the Higgs field. Including higher order corrections the Z mass is predicted with a precision of better than 10 MeV, which corresponds to one part in 10,000. The Z mass was measured to 2 MeV by the four LEP experiments in a beam-energy scan of the LEP e+e- collider. Meanwhile, hadron collider experiments have dominated the measurements of the W boson mass, but their studies of the Z boson mass have been primarily in the context of calibrations for the W mass analyses.
Here we present the first dedicated Z boson mass measurement in proton-proton collisions. The data were recorded in 2016 by the LHCb experiment and correspond to an integrated luminosity of 1.7 fb-1. The Z mass is determined from a fit to the dimuon mass distribution in Z -> mu+mu- decays. Templates from simulation are used in the fit, with a momentum calibration based on quarkonium resonance decays. The result is compared with previous measurements of the Z mass and with the predicted value from the global electroweak fit.
Refreshments will be served at 10h30 .
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The talk
Credits and licence
- Institution
- CERN
- Department
- LHC Seminar
- Speaker
- Emir Muhammad
- Year
- 2025
- Language
- English
- Source
- CERN
- Licence
- CERN, as CERN states it. CERN's terms
- Attribution
- © CERN. CERN provides its audiovisual media free of charge for educational and informational use, credited to CERN; this lecture is shown in CERN's own player.
- Who can watch
- CERN gives no rating. Invisible Network shows it to Teens profiles and older, judged from what the source says about it. How courses are placed