Complementarity of direct dark matter detection and indirect detection through gamma-rays

TL;DR

This paper demonstrates that indirect dark matter detection via gamma rays, especially with next-generation telescopes like the proposed Dark Matter Array, can explore parameter spaces inaccessible to direct detection and collider searches, offering a complementary approach.

Contribution

It introduces the potential of gamma-ray indirect detection as a powerful, complementary method for probing supersymmetric dark matter models, including those beyond current experimental reach.

Findings

Gamma-ray detection can identify dark matter models undetectable by direct detection.

Next-generation Cherenkov telescopes could extend current limits by orders of magnitude.

Multiple detection methods may be necessary for conclusive dark matter identification.

Abstract

We show, by using an extensive sample of viable supersymmetric models as templates, that indirect detection of dark matter through gamma rays may have a large potential for identifying the nature of dark matter. This is in particular true also for models that give too weak dark matter-nucleon scattering cross sections to be probed by present and planned direct detection experiments. Also models with a mass scale too high to be accessible at CERN's LHC accelerator may show up in next-generation imaging Cherenkov telescope arrays. Based on our our findings, we therefore suggest to view indirect searches as genuine particle physics experiments, complementing other strategies to probe so far unknown regions in the parameter space of e.g. supersymmetric models, and propose a new approach that would make use of telescopes dedicated for dark matter searches. As a concrete example for the potential of such an approach, we consider an array of imaging air Cherenkov telescopes, the Dark Matter Array (DMA), and show that such an experiment could extend present-day limits by several orders of magnitude, reaching a large class of models that would remain undetected in both direct detection experiments and searches at the LHC. In addition, in a sizable part of the parameter space, signals from more than one type of dark matter detection experiment would be possible, something that may eventually be necessary in order to identify the dark matter candidate.