Measurement of the properties of a Higgs boson in the four-lepton final state

S. Chatrchyan , S. Baffioni (1) , F. Beaudette (1) , P. Busson (1) , C. Charlot (1) , N. Daci (1) , T. Dahms (1) , M. Dalchenko (1) , L. Dobrzynski (1) , A. Florent (1) , R. Granier de Cassagnac (1) , P. Mine (1) , C. Mironov (1) , I.N. Naranjo (1) , M. Nguyen (1) , C. Ochando (1) , P. Paganini (1) , D. Sabes (1) , R. Salerno (1) , Y. Sirois (1) , C. Veelken (1) , Y. Yilmaz (1) , A. Zabi (1) , J.-L. Agram (2) , J. Andrea (2) , D. Bloch (2) , J.-M. Brom (2) , E.C. Chabert (2) , C. Collard (2) , E. Conte (2) , F. Drouhin (2) , J.-C. Fontaine (2) , D. Gele (2) , U. Goerlach (2) , C. Goetzmann (2) , P. Juillot (2) , A.-C. Le Bihan (2) , P. van Hove (2) , S. Gadrat (3) , S. Beauceron (4) , N. Beaupere (4) , G. Boudoul (4) , S. Brochet (4) , J. Chasserat (4) , R. Chierici (4) , D. Contardo (4) , P. Depasse (4) , H. El Mamouni (4) , J. Fan (4) , J. Fay (4) , S. Gascon (4) , M. Gouzevitch (4) , B. Ille (4) , T. Kurca (4) , M. Lethuillier (4) , L. Mirabito (4) , S. Perries (4) , J.D. Ruiz Alvarez (4) , L. Sgandurra (4) , V. Sordini (4) , M. Vander Donckt (4) , P. Verdier (4) , S. Viret (4) , H. Xiao (4)

1 LLR - Laboratoire Leprince-Ringuet
2 IPHC - Institut Pluridisciplinaire Hubert Curien
3 CC-IN2P3 - Centre de Calcul de l'IN2P3
4 IPNL - Institut de Physique Nucléaire de Lyon

The properties of a Higgs boson candidate are measured in the H to ZZ to 4l decay channel, with l=e,mu, using data from pp collisions corresponding to an integrated luminosity of 5.1 inverse femtobarns at center-of-mass energy of sqrt(s)=7 TeV and 19.7 inverse femtobarns at sqrt(s)=8 TeV, recorded with the CMS detector at the LHC. The new boson is observed as a narrow resonance with a local significance of 6.8 standard deviations, a measured mass of 125.6+/-0.4 (stat.) +/-0.2 (syst.) GeV, and a total width less than 3.4 GeV at a 95% confidence level. The production cross section of the new boson times the branching fraction to four leptons is measured to be 0.93+0.26/-0.23 (stat.) +0.13/-0.09} (syst.) times that predicted by the standard model. Its spin-parity properties are found to be consistent with the expectations for the standard model Higgs boson. The hypotheses of a pseudoscalar and all tested spin-one boson hypotheses are excluded at a 99% confidence level or higher. All tested spin-two boson hypotheses are excluded at a 95% confidence level or higher.

Domaines: Physique des Hautes Energies - Expérience [hep-ex]

S. Chatrchyan, S. Baffioni, F. Beaudette, P. Busson, C. Charlot, et al.. Measurement of the properties of a Higgs boson in the four-lepton final state. Physical Review D, 2014, 89, pp.092007. ⟨10.1103/PhysRevD.89.092007⟩. ⟨in2p3-00921190⟩