Abstract
This Letter presents direct searches for lepton flavour violation in Higgs boson decays, H→eτ and H→μτ, performed with the ATLAS detector at the LHC. The searches are based on a data sample of proton–proton collisions at a centre-of-mass energy s=13 TeV, corresponding to an integrated luminosity of 36.1 fb−1. No significant excess is observed above the expected background from Standard Model processes. The observed (median expected) 95% confidence-level upper limits on the lepton-flavour-violating branching ratios are 0.47% (0.34−0.10+0.13%) and 0.28% (0.37−0.10+0.14%) for H→eτ and H→μτ, respectively.
Highlights
The search for processes beyond the Standard Model (SM) is one of the main goals of the Large Hadron Collider (LHC) programme at CERN
The measured values are obtained by the fit to data, while the expected values are determined by the fit to a background-only sample
These limits are more stringent by a factor of 2 (5) than the corresponding√limits for the H → eτ (H → μτ ) decay determined by ATLAS at s = 8 TeV
Summary
The search for processes beyond the Standard Model (SM) is one of the main goals of the Large Hadron Collider (LHC) programme at CERN. A possible sign of such processes is lepton flavour violation (LFV) in decays of the Higgs boson [1,2]. The dataset corresponds to an integrated luminosity of 36.1 fb−1. (1.43%) on the H → eτ (H → μτ ) branching ratio√(B) with a 95% confidence level (CL) using Run 1 data collected at s = 8 TeV, corresponding to an integrated luminosity of 20.3 fb−1. √ing ratios of 0.61% s = 13 TeV, with and 0.25%, respectively, using data collected an integrated luminosity of 35.9 fb−1 [16]. The dilepton final state τ only considers pairs of different-flavour leptons. It consists of an inner tracking detector covering the range |η| < 2.5, surrounded by a superconducting solenoid providing a 2 T axial magnetic field, high-granularity electromagnetic (|η| < 3.2) and hadronic calorimeters (|η| < 4.9), and a muon spectrometer (MS) which covers the range |η| < 2.7 and includes fast trigger chambers (|η| < 2.4) and superconducting toroidal magnets
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
