Speaker
Description
The decay $H \rightarrow Z\gamma$ is a rare process predicted by the Standard Model that has not yet been individually observed by either ATLAS or CMS. It proceeds through loop diagrams and is therefore highly sensitive to potential effects of new physics. As such, the search for $H \rightarrow Z\gamma$ provides an important window into physics beyond the Standard Model.
During Run 3, the ATLAS experiment collected $pp$ collision data at a center-of-mass energy of $\sqrt{s}=13.6$ TeV, corresponding to an integrated luminosity of 165 fb$^{-1}$ over the years 2022--2024.
Combined with ATLAS full Run 2 dataset, the ATLAS $H \rightarrow Z\gamma$ analysis has achieved the most stringent expected sensitivity to date for this rare decay. The observed (expected) signal strength is determined to be $\mu = 1.3^{+0.6}_{-0.5}$ ($\mu = 1.0^{+0.6}_{-0.5}$), corresponding to an observed (expected) significance of 2.5 (1.9) standard deviations.
| Session Selection | Particle and Nuclear Physics |
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