Wobbly Dark Matter Signals at Cherenkov Telescopes from Long Lived Mediator Decays

Abstract

Imaging Atmospheric Cherenkov Telescope (IACT) searches for dark matter often perform observations in "wobble mode", i.e. collecting data from the signal region and from a corresponding background control region at the same time, enabling efficient simultaneous determination and subtraction of background. This observation strategy is possibly compromised in scenarios where dark matter annihilates to long-lived mediators that can traverse astrophysical distances before decaying to produce the gamma rays observed by the IACTs. In this paper, we show that this challenge comes with several interesting features and opportunities: in addition to signal contamination in the background control region, the gamma-ray spectrum changes with the observing direction angle and typically exhibits a hard excess at high energies. This affects signal reconstruction via subtraction of the background control region measurements in non-trivial ways. Such features represent a significant departure from the canonical picture, and offer novel handles to identify a dark matter signal and to extract underlying dark matter parameters.

6 pages, 5 figures

References in corpus (10)

• Secluded WIMP Dark Matter
• General Constraints on Dark Matter Decay from the Cosmic Microwave Background
• Cosmological constraints on exotic injection of electromagnetic energy
• Dwarf galaxy annihilation and decay emission profiles for dark matter experiments
• Spherical Jeans analysis for dark matter indirect detection in dwarf spheroidal galaxies - Impact of physical parameters and triaxiality
• Non-universal BBN bounds on electromagnetically decaying particles
• Phenomenology of Dark Matter annihilation into a long-lived intermediate state
• SUSY Implications from WIMP Annihilation into Scalars at the Galactic Centre
• Off-Diagonal Dark-Matter Phenomenology: Exploring Enhanced Complementarity Relations in Non-Minimal Dark Sectors
• Dark matter indirect signals with long-lived mediators

Cited by in corpus (4)

• "Non-Local" Effects from Boosted Dark Matter in Indirect Detection
• Bouncing Dark Matter
• Searching for dark matter annihilating into light long-lived mediators from stars inside dwarf spheroidal galaxies
• Indirect detection of long-lived particles in a rich dark sector with a dark vector portal