Status of indirect searches in the PAMELA and Fermi era

TL;DR

This paper reviews the status of indirect dark matter searches using gamma-rays, antiprotons, and positrons, highlighting recent experimental results from PAMELA, Fermi, PPB-BETS, and ATIC, and discussing their implications for dark matter models.

Contribution

It provides an updated overview of indirect dark matter detection efforts and analyzes how recent data constrain or suggest potential dark matter signals within specific theoretical frameworks.

Findings

PAMELA antiproton data align with standard secondary production.

PAMELA positron data show an excess beyond secondary explanations.

Electron spectrum features at a few hundred GeV suggest additional sources.

Abstract

The detection of gamma-rays, antiprotons and positrons due to pair annihilation of dark matter particles in the Milky Way halo is a viable indirect technique to search for signatures of supersymmetric dark matter where the major challenge is the discrimination of the signal from the background generated by standard production mechanisms. The new PAMELA antiproton data are consistent with the standard secondary production and this allows us to constrain exotic contribution to the spectrum due to neutralino annihilations. In particular, we show that in the framework of minimal supergravity (mSUGRA), in a clumpy halo scenario (with clumpiness factor > 10) and for large values of tan(beta)> 55, almost all the parameter space allowed by WMAP is excluded. Instead, the PAMELA positron fraction data exhibit an excess that cannot be explained by secondary production. PPB-BETS and ATIC reported a feature in electron spectrum at a few hundred GeV. The excesses seem to be consistent and imply a source, conventional or exotic, of additional leptonic component. Here we discuss the status of indirect dark matter searches and a perspective forPAMELA and Fermi gamma-ray space telescope (Fermi) experiments.