The Status and future of ground-based TeV gamma-ray astronomy A White Paper prepared for the Division of Astrophysics of the American Physical Society

1 Summary and Overview 1 1.1 Executive Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.1.1 Summary of findings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.1.2 Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.2 Ground based γ-ray astronomy historical milestones . . . . . . . . . . . . . . . . . 4 1.3 Scientific overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1.3.1 Unveiling an important component of our Universe: high-energy particles . . 6 1.3.2 Radiation processes and the sky in high-energy γ-rays . . . . . . . . . . . . . 7 1.3.3 Diffuse emission and the nature and distribution of dark matter . . . . . . . . 9 1.3.4 Powerful particle accelerators in our Milky Way Galaxy: supernova remnants, pulsars, and stellar mass black holes . . . . . . . . . . . . . . . . . . . . . . . 9 1.3.5 Extragalactic sources of TeV γ-rays . . . . . . . . . . . . . . . . . . . . . . . 10 1.4 Technology and the path toward a future observatory . . . . . . . . . . . . . . . . . 11 1.5 Synergies with other wavebands and particle astronomy missions . . . . . . . . . . . 13