The Sensitivity of HAWC to High-Mass Dark Matter Annihilations

Abstract

The High Altitude Water Cherenkov (HAWC) observatory is a wide field-of-view detector sensitive to gamma rays of 100 GeV to a few hundred TeV. Located in central Mexico at 19 degrees North latitude and 4100 m above sea level, HAWC will observe gamma rays and cosmic rays with an array of water Cherenkov detectors. The full HAWC array is scheduled to be operational in Spring 2015. In this paper, we study the HAWC sensitivity to the gamma-ray signatures of high-mass (multi- TeV) dark matter annihilation. The HAWC observatory will be sensitive to diverse searches for dark matter annihilation, including annihilation from extended dark matter sources, the diffuse gamma-ray emission from dark matter annihilation, and gamma-ray emission from non-luminous dark matter subhalos. Here we consider the HAWC sensitivity to a subset of these sources, including dwarf galaxies, the M31 galaxy, the Virgo cluster, and the Galactic center. We simulate the HAWC response to gamma rays from these sources in several well-motivated dark matter annihilation channels. If no gamma-ray excess is observed, we show the limits HAWC can place on the dark matter cross-section from these sources. In particular, in the case of dark matter annihilation into gauge bosons, HAWC will be able to detect a narrow range of dark matter masses to cross-sections below thermal. HAWC should also be sensitive to non-thermal cross-sections for masses up to nearly 1000 TeV. The constraints placed by HAWC on the dark matter cross-section from known sources should be competitive with current limits in the mass range where HAWC has similar sensitivity. HAWC can additionally explore higher dark matter masses than are currently constrained.

15 pages, 4 figures, version to be published in PRD

References in corpus (16)

• PYTHIA 6.4 Physics and Manual
• Observation of an anomalous positron abundance in the cosmic radiation
• Dark Matter Candidates from Particle Physics and Methods of Detection
• Precise Relic WIMP Abundance and its Impact on Searches for Dark Matter Annihilation
• Cosmic-Ray Proton and Helium Spectra from the First CREAM Flight
• Milagro Observations of Multi-TeV Emission from Galactic Sources in the Fermi Bright Source List
• Discovery of Localized Regions of Excess 10-TeV Cosmic Rays
• Inverse Compton constraints on the Dark Matter e+e- excesses
• TeV gamma-rays and the largest masses and annihilation cross sections of neutralino dark matter
• Observation of Cosmic Ray Anisotropy with the IceTop Air Shower Array
• Galactic Substructure and Dark Matter Annihilation in the Milky Way Halo
• H.E.S.S. constraints on Dark Matter annihilations towards the Sculptor and Carina Dwarf Galaxies
• Constraining Extended Gamma-ray Emission from Galaxy Clusters
• Extragalactic Inverse Compton Light from Dark Matter Annihilation and the Pamela Positron Excess
• A Robust Approach to Constraining Dark Matter from Gamma-Ray Data
• Photocathode-Uniformity Tests of the Hamamatsu R5912 Photomultiplier Tubes Used in the Milagro Experiment

Cited by in corpus (5)

• Neutrino Lighthouse at Sagittarius A*
• Ground-based gamma-ray astronomy: history and development of techniques
• D-brane Disformal Coupling and Thermal Dark Matter
• The prediction of using LHAASO's cosmic-ray electron measurements to constrain decaying heavy dark matter
• Primordial Black Holes: A Review of Formation and Evolution