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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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Light Curves and Event Rates of Axion Instability Supernovae
Abstract It was recently proposed that exotic particles can trigger a new stellar instability that is analogous to thee−e+pair instability if they are produced and reach equilibrium in the stellar plasma. In this study, we construct axion instability supernova (AISN) models caused by the new instability to predict their observational signatures. We focus on heavy axion-like particles (ALPs) with masses of ∼400 keV–2 MeV and coupling with photons ofgaγ∼ 10−5GeV−1. It is found that the56Ni mass and the explosion energy are significantly increased by ALPs for a fixed stellar mass. As a result, the peak times of the light curves of AISNe occur earlier than those of standard pair-instability supernovae by 10–20 days when the ALP mass is equal to the electron mass. Also, the event rate of AISNe is 1.7–2.6 times higher than that of pair-instability supernovae, depending on the high mass cutoff of the initial mass function.
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- PAR ID:
- 10392212
- Publisher / Repository:
- DOI PREFIX: 10.3847
- Date Published:
- Journal Name:
- The Astrophysical Journal
- Volume:
- 943
- Issue:
- 1
- ISSN:
- 0004-637X
- Format(s):
- Medium: X Size: Article No. 12
- Size(s):
- Article No. 12
- Sponsoring Org:
- National Science Foundation
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