UFRGS-HEP Journal Club
Friday 25 August 2023 -
13:30
Monday 21 August 2023
Tuesday 22 August 2023
Wednesday 23 August 2023
Thursday 24 August 2023
Friday 25 August 2023
13:30
Tulio Kuhn
Tulio Kuhn
13:30 - 14:30
Measurement of the Higgs boson width and evidence of its off-shell contributions to ZZ production [CMS Collaboration] Nat. Phys. 18 (2022) 1329 Hide abstract | Show figures | Show BibTeX | Show discussion | View PDF | 2202.06923v2 Since the discovery of the Higgs boson in 2012, detailed studies of its properties have been ongoing. Besides its mass, its width - related to its lifetime - is an important parameter. One way to determine this quantity is by measuring its off-shell production, where the Higgs boson mass is far away from its nominal value, and relating it to its on-shell production, where the mass is close to the nominal value. Here, we report evidence for such off-shell contributions to the production cross section of two Z bosons with data from the CMS experiment at the CERN Large Hadron Collider. We constrain the total rate of the off-shell Higgs boson contribution beyond the Z boson pair production threshold, relative to its standard model expectation, to the interval [0.0061, 2.0] at 95% confidence level. The scenario with no off-shell contribution is excluded at a p-value of 0.0003 (3.6 standard deviations). We measure the width of the Higgs boson as ΓH = 3.2 +2.4−1.7 MeV, in agreement with the standard model expectation of 4.1 MeV. In addition, we set constraints on anomalous Higgs boson couplings to W and Z boson pairs. Authors' comments: Replaced with the published version. Added the journal reference and the DOI. All the figures and tables can be found at http://cms-results.web.cern.ch/cms-results/public-results/publications/HIG-21-013 (CMS Public Pages). Nat. Phys. (2022)