Evidence for the Dimuon Decay of the Higgs Boson in 𝑝𝑝 Collisions with the ATLAS Detector
A search for the dimuon decay of the Higgs boson is presented based on 𝑝𝑝 collision data recorded by ATLAS during Run 3 of the Large Hadron Collider, corresponding to an integrated luminosity of 165 fb −1 at $\sqrt{s}$ = 13.6 TeV. To enhance the sensitivity, the results are combined with those from Run 2. An excess of events over the background is observed with a significance of 3.4𝜎 (2.5𝜎 expected). The best-fit signal strength is 𝜇 = 1.4 ± 0.4. This result provides evidence for the 𝐻 → 𝜇𝜇 decay with ATLAS data and offers a direct probe of the Higgs-boson Yukawa coupling to second-generation fermions.