Search for dark matter using sub-PeV $\boldsymbol{\gamma}$-rays observed by Tibet AS$_{\boldsymbol{\gamma}}$

TL;DR

The Tibet ASγ collaboration's discovery of diffuse sub-PeV gamma-rays offers new constraints on PeV-scale decaying dark matter, with potential for future detection of such dark matter through high-energy gamma-ray observations.

Contribution

This study provides the first comprehensive analysis of how sub-PeV gamma-ray data constrains PeV-scale decaying dark matter models across various decay channels and astrophysical backgrounds.

Findings

Established the most stringent limits on dark matter lifetime for PeV masses.

Identified the energy range where constraints are strongest (a few PeV to tens of PeV).

Highlighted the potential of future gamma-ray data to detect PeV-scale decaying dark matter.

Abstract

The discovery of diffuse sub-PeV gamma-rays by the Tibet AS$_\gamma$ Collaboration promises to revolutionize our understanding of the high-energy astrophysical universe. It has been shown that these data broadly agree with prior theoretical expectations. We study the impact of this discovery on a well-motivated new physics scenario: PeV-scale decaying dark matter (DM). Considering a wide range of final states in DM decay, a number of DM density profiles, and numerous astrophysical background models, we find that these data provide the most stringent limit on DM lifetime for various Standard Model final states. In particular, we find that the strongest constraints are derived for DM masses in between a few PeV to a few tens of PeV. Near-future data of these high-energy gamma-rays can be used to discover PeV-scale decaying DM.