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  • Search for Higgs boson exotic decays into Lorentz-boosted light bosons in the four- Ο„ final state at sqrt(13)TeV with the ATLAS detector

This content will become publicly available on November 1, 2026

Title: Search for Higgs boson exotic decays into Lorentz-boosted light bosons in the four- Ο„ final state at sqrt(13)TeV with the ATLAS detector
A search for exotic decays of the Higgs boson into a pair of low-mass scalars that subsequently decay into 𝜏-leptons, 𝐻 β†’ π‘Žπ‘Ž β†’ 𝜏+ πœβˆ’πœ+ πœβˆ’, is presented. In models with Yukawa-like couplings, the decay to 𝜏-leptons is favoured for light π‘Ž-bosons, with mass in the range of 2π‘šπœ < π‘šπ‘Ž < 2π‘šπ‘. Results are presented in the range of 4 GeV < π‘šπ‘Ž < 15 GeV using the 140 f bβˆ’1 of proton–proton collisions at βˆšπ‘  = 13 TeV recorded with the ATLAS detector during Run 2 of the Large Hadron Collider. This search focuses on the scenario where, for both di-𝜏 pairs, one of the 𝜏-leptons decays to hadrons and neutrinos, while the other decays to a muon and neutrinos. In this mass range, the π‘Ž β†’ 𝜏+ πœβˆ’ is Lorentz-boosted and a dedicated muon removal technique is used to reconstruct the di-𝜏 pairs. No significant excess above the Standard Model background prediction is observed. Upper limits on (𝜎(𝐻)βˆ•πœŽSM (𝐻)) Γ— Br(𝐻 β†’ π‘Žπ‘Ž β†’ 4𝜏) at 95 % confidence level are provided, ranging from 0.03 to 0.10 depending on the π‘Ž-boson mass.  more » « less
Award ID(s):
2111511
PAR ID:
10654227
Author(s) / Creator(s):
Publisher / Repository:
Physics Letters B
Date Published:
Journal Name:
Physics Letters B
Volume:
870
Issue:
C
ISSN:
0370-2693
Page Range / eLocation ID:
139843
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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