Search for Dark Matter decay signals in the Galactic Halo with the MAGIC telescopes

TL;DR

This study uses MAGIC telescopes to search for dark matter decay signals in the Galactic Halo by comparing observations at different angles to cancel out diffuse backgrounds, setting new limits on TeV dark matter particle lifetime.

Contribution

Developed a novel background estimation method by comparing paired observations at different Galactic angles to isolate dark matter decay signals.

Findings

Achieved a systematic uncertainty of 4.8% in background estimation.

Set new limits on TeV dark matter particle lifetime of 10^26 seconds.

Collected 20 hours of observational data in 2018.

Abstract

MAGIC is a system of two Cherenkov telescopes located in the Canary island of La Palma. A key part of MAGIC Fundamental Physics program is the search for indirect signals of Dark Matter (DM) from different sources. In the Milky Way, DM forms an almost spherically symmetric halo, with a density peaked towards the center of the Galaxy and decreasing toward the outer region. We search for DM decay signals from the Galactic Halo, with a special methodology developed for this work. Our strategy is to compare pairs of observations performed at different angular distances from the Galactic Center, selected in such a way that all the diffuse components cancel out, except for those coming from the DM. In order to keep the systematic uncertainty of this novel background estimation method down to a minimum, the observation pairs have been acquired during the same nights and follow exactly the same azimuth and zenith paths. We collected 20 hours of data during 2018. Using half of them to determine the systematic uncertainty in the background estimation of our analysis, we obtain a value of 4.8\% with no dependence on energy. Accounting for this systematic uncertainty in the likelihood analysis based on the 10 remaining hours of data collected so far, we present the limit to TeV DM particle with a lifetime of $10^{26}$ s in the $\mathrm{b\bar{b}}$ decay channel.