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A<sc>bstract</sc> We report a search for an axion-like particleainB→K(*)adecays using data collected with the Belle detector at the KEKB asymmetric-energy electron-positron collider. The search is based on a 711 fb−1data sample collected at the Υ(4S) resonance energy, corresponding to a sample of 772 × 106Υ(4S) events. In this study, we search for the decay of the axion-like particle into a pair of photons,a→γγ. We scan the two-photon invariant mass in the range 0.16 GeV–4.50 GeV for theKmodes and 0.16 GeV–4.20 GeV for theK*modes. No significant signal is observed in any of the modes, and 90% confidence level upper limits are established on the coupling to theWboson,gaW, as a function ofamass. The limits range from 3×10−6GeV−1to 3×10−5GeV−1, improving the current constraints ongaWby a factor of two over the most stringent previous experimental results.
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Probing axion-like particles at the Electron-Ion Collider
A<sc>bstract</sc> The Electron-Ion Collider (EIC), a forthcoming powerful high-luminosity facility, represents an exciting opportunity to explore new physics. In this article, we study the potential of the EIC to probe the coupling between axion-like particles (ALPs) and photons in coherent scattering. The ALPs can be produced via photon fusion and decay back to two photons inside the EIC detector. In a prompt-decay search, we find that the EIC can set the most stringent bound forma≲ 20 GeV and probe the effective scales Λ ≲ 105GeV. In a displaced-vertex search, which requires adopting an EM calorimeter technology that provides directionality, the EIC could probe ALPs withma≲ 1 GeV at effective scales Λ ≲ 107GeV. Combining the two search strategies, the EIC can probe a significant portion of unexplored parameter space in the 0.2 <ma< 20 GeV mass range.
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- Award ID(s):
- 2209181
- PAR ID:
- 10506605
- Publisher / Repository:
- Springer
- Date Published:
- Journal Name:
- Journal of High Energy Physics
- Volume:
- 2024
- Issue:
- 2
- ISSN:
- 1029-8479
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1007/JHEP02(2024)123
