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arXiv · 1507.06656

Limits on the Higgs boson lifetime and width from its decay to four charged leptons

Abstract

Constraints on the lifetime and width of the Higgs boson are obtained from H to ZZ to 4 lepton events using data recorded by the CMS experiment during the LHC run 1 with an integrated luminosity of 5.1 and 19.7 inverse femtobarns at a center-of-mass energy of 7 and 8 TeV, respectively. The measurement of the Higgs boson lifetime is derived from its flight distance in the CMS detector with an upper bound of tau[H] < 1.9E-13 s at the 95% confidence level (CL), corresponding to a lower bound on the width of Gamma[H] > 3.5E-9 MeV. The measurement of the width is obtained from an off-shell production technique, generalized to include anomalous couplings of the Higgs boson to two electroweak bosons. From this measurement, a joint constraint is set on the Higgs boson width and a parameter f[LQ] that expresses an anomalous coupling contribution as an on-shell cross-section fraction. The limit on the Higgs boson width is Gamma[H] < 46 MeV with f[LQ] unconstrained and Gamma[H] < 26 MeV for f[LQ] = 0 at the 95% CL. The constraint f[LQ] < 3.8E-3 at the 95% CL is obtained for the expected standard model Higgs boson width.

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BibTeXRIS

CMS Collaboration. 2015-11-11. Limits on the Higgs boson lifetime and width from its decay to four charged leptons. https://doi.org/10.1103/physrevd.92.072010

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