# Dark Matter Constraints from a Joint Analysis of Dwarf Spheroidal Galaxy Observations with VERITAS

## TL;DR

This paper uses joint analysis of gamma-ray observations from four dwarf galaxies with VERITAS to set new upper limits on WIMP dark matter annihilation cross sections, improving detection sensitivity through spectral and spatial photon analysis.

## Contribution

It introduces an optimized photon weighting technique for IACT data, enhancing dark matter search sensitivity by combining multiple dwarf galaxy observations.

## Key findings

- No gamma-ray emission detected from individual or joint analysis.
- Upper limits on dark matter annihilation cross section are established at various final states.
- Method improves constraints compared to previous analyses.

## Abstract

We present constraints on the annihilation cross section of WIMP dark matter based on the joint statistical analysis of four dwarf galaxies with VERITAS. These results are derived from an optimized photon weighting statistical technique that improves on standard imaging atmospheric Cherenkov telescope (IACT) analyses by utilizing the spectral and spatial properties of individual photon events. We report on the results of $\sim$230 hours of observations of five dwarf galaxies and the joint statistical analysis of four of the dwarf galaxies. We find no evidence of gamma-ray emission from any individual dwarf nor in the joint analysis. The derived upper limit on the dark matter annihilation cross section from the joint analysis is $1.35\times 10^{-23} {\mathrm{ cm^3s^{-1}}}$ at 1 TeV for the bottom quark ($b\bar{b}$) final state, $2.85\times 10^{-24}{\mathrm{ cm^3s^{-1}}}$ at 1 TeV for the tau lepton ($\tau^{+}\tau^{-}$) final state and $1.32\times 10^{-25}{\mathrm{ cm^3s^{-1}}}$ at 1 TeV for the gauge boson ($\gamma\gamma$) final state.