Presented is the search for anomalous Higgs boson decays into two axion-like particles (ALPs) using the full Run 2 data set of of proton-proton collisions at a centre-of-mass energy of recorded by the ATLAS experiment. The ALPs are assumed to decay into two photons, providing sensitivity to recently proposed models that could explain the discrepancy. This analysis covers an ALP mass range from 100 to and ALP-photon couplings in the range , and therefore includes signatures with significantly displaced vertices and highly collinear photons. No significant excess of events above the Standard Model background is observed. Upper limits at 95% confidence level are placed on the branching ratio of the Higgs boson to two ALPs in the four-photon final state, and are in the range of to , depending on the hypothesized ALP mass and ALP-photon coupling strength.
Search for short- and long-lived axion-like particles in H→αα→4γ decays with the ATLAS experiment at the LHC
M. Cristoforetti;A. Di Luca
2024-01-01
Abstract
Presented is the search for anomalous Higgs boson decays into two axion-like particles (ALPs) using the full Run 2 data set of of proton-proton collisions at a centre-of-mass energy of recorded by the ATLAS experiment. The ALPs are assumed to decay into two photons, providing sensitivity to recently proposed models that could explain the discrepancy. This analysis covers an ALP mass range from 100 to and ALP-photon couplings in the range , and therefore includes signatures with significantly displaced vertices and highly collinear photons. No significant excess of events above the Standard Model background is observed. Upper limits at 95% confidence level are placed on the branching ratio of the Higgs boson to two ALPs in the four-photon final state, and are in the range of to , depending on the hypothesized ALP mass and ALP-photon coupling strength.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.