Speaker
Description
Dark matter (DM) is largely believed to be the dominant component of the matter content of the Universe. Astronomical measurements can be utilized to search for Standard Model annihilation or decay products of DM, complementing direct and collider-based searches. Among DM particle candidates, Weakly Interacting Massive Particles (WIMPs) are an attractive one. Their decay or annihilation could produce secondary particles including very-high-energy (VHE: E>100 GeV) gamma rays, which could be detected by imaging atmospheric Cherenkov Telescopes (IACTs). One of the most favourable target classes for DM searches are Dwarf Spheroidal galaxies (dSphs), dark matter-dominated objects with a negligible predicted gamma-ray emission due to apparent absence of gas and on-going star formation. The IACTs, whose Point Spread Function (PSF, defined as 68% containment) is typically 0.1 deg at 1 TeV, have the necessary angular resolution to detect extended emission from some dSphs. Thus, an extended source analysis may give an improvement to DM sensitivity, compared to a point source analysis. In this work, we use observations made since 2007 by VERITAS, an array of four imaging atmospheric Cherenkov telescopes sensitive to VHE gamma rays in the 100 GeV - 30 TeV energy range. We perform an unbinned combined likelihood analysis incorporating the dSph angular profiles of several dSphs. A new analysis technique utilising boosted decision trees has also been applied, to improve the overall dark matter sensitivity of the experiment. We interpret the results in terms of the DM self-annihilation cross-section as a function of the DM particle mass.
Keywords
Dark Matter search in Dwarf Spheroidal galaxies with VERITAS (IACT)
| Subcategory | Experimental Results |
|---|---|
| Collaboration | VERITAS |
