Constraints on axino warm dark matter from X-ray observation at the Chandra telescope and SPI

TL;DR

This paper investigates how X-ray observations from Chandra and SPI telescopes constrain axino dark matter properties, finding significant limits on axinos but not on gravitinos within certain mass ranges.

Contribution

It provides new constraints on axino warm dark matter using satellite X-ray data, highlighting the impact of decay constants and R-parity violation.

Findings

Axino dark matter is constrained by X-ray observations, especially at low decay constants.

Gravitino dark matter remains unconstrained by the same observations.

X-ray data limits the parameter space for axino masses and decay constants.

Abstract

A sufficiently long lived warm dark matter could be a source of X-rays observed by satellite based X-ray telescopes. We consider axinos and gravitinos with masses between 1 keV and 100 keV in supersymmetric models with small R-parity violation. We show that axino dark matter receives significant constraints from X-ray observations of Chandra and SPI, especially for the lower end of the allowed range of the axino decay constant $f_{a}$, while the gravitino dark matter remains unconstrained.