A search is presented for a Higgs boson that is produced in association with a Z boson and that decays to an undetected particle together with an isolated photon. The search is performed by the CMS Collaboration at the Large Hadron Collider using a data set corresponding to an integrated luminosity of 137 fb−1 recorded at a center-of-mass energy of 13 TeV. No significant excess of events above the expectation from the standard model background is found. The results are interpreted in the context of a theoretical model in which the undetected particle is a massless dark photon. An upper limit is set on the product of the cross section for associated Higgs and Z boson production and the branching fraction for such a Higgs boson decay, as a function of the Higgs boson mass. For a mass of 125 GeV, assuming the standard model production cross section, this corresponds to an observed (expected) upper limit on this branching fraction of 4.6 (3.6)% at 95% confidence level. These are the first limits on Higgs boson decays to final states that include an undetected massless dark photon. [Figure not available: see fulltext.].

Search for dark photons in decays of Higgs bosons produced in association with Z bosons in proton-proton collisions at √s = 13 TeV / Sirunyan, A.M., Tumasyan, A., Adam, W., Ambrogi, F., Bergauer, T., Brandstetter, J., Dragicevic, M., Ero, J., Escalante Del Valle, A., Flechl, M., Fruhwirth, R., Jeitler, M., Krammer, N., Kratschmer, I., Liko, D., Madlener, T., Mikulec, I., Rad, N., Schieck, J., Schofbeck, R., et al.. - In: JOURNAL OF HIGH ENERGY PHYSICS. - ISSN 1126-6708. - 2019:10(2019). [10.1007/JHEP10(2019)139]

Search for dark photons in decays of Higgs bosons produced in association with Z bosons in proton-proton collisions at √s = 13 TeV

Cipriani M.;Del Re D.;Longo E.;Organtini G.;Paramatti R.;Quaranta C.;Rahatlou S.;Santanastasio F.;
2019

Abstract

A search is presented for a Higgs boson that is produced in association with a Z boson and that decays to an undetected particle together with an isolated photon. The search is performed by the CMS Collaboration at the Large Hadron Collider using a data set corresponding to an integrated luminosity of 137 fb−1 recorded at a center-of-mass energy of 13 TeV. No significant excess of events above the expectation from the standard model background is found. The results are interpreted in the context of a theoretical model in which the undetected particle is a massless dark photon. An upper limit is set on the product of the cross section for associated Higgs and Z boson production and the branching fraction for such a Higgs boson decay, as a function of the Higgs boson mass. For a mass of 125 GeV, assuming the standard model production cross section, this corresponds to an observed (expected) upper limit on this branching fraction of 4.6 (3.6)% at 95% confidence level. These are the first limits on Higgs boson decays to final states that include an undetected massless dark photon. [Figure not available: see fulltext.].
2019
Beyond Standard Model; Hadron-Hadron scattering (experiments); Photon production
01 Pubblicazione su rivista::01a Articolo in rivista
Search for dark photons in decays of Higgs bosons produced in association with Z bosons in proton-proton collisions at √s = 13 TeV / Sirunyan, A.M., Tumasyan, A., Adam, W., Ambrogi, F., Bergauer, T., Brandstetter, J., Dragicevic, M., Ero, J., Escalante Del Valle, A., Flechl, M., Fruhwirth, R., Jeitler, M., Krammer, N., Kratschmer, I., Liko, D., Madlener, T., Mikulec, I., Rad, N., Schieck, J., Schofbeck, R., et al.. - In: JOURNAL OF HIGH ENERGY PHYSICS. - ISSN 1126-6708. - 2019:10(2019). [10.1007/JHEP10(2019)139]
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11573/1349887
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