UCLA

A vast number of independent astrophysical and cosmological observations suggest that the dominant form of matter in the Universe, known as dark matter, is neither luminous nor baryonic. Despite nearly half a decade of research, the non-gravitational nature of dark matter, if any, remains a mystery. Motivated primarily by preferred theoretical extensions of the Standard Model and a relatively simple production mechanism, the weakly interacting massive particle (WIMP) has long been considered to be among the most appealing dark matter particle candidates. This dissertation is comprised of largely independent works that focus on understanding and constraining various signals that could arise from WIMP dark matter. Specifically, Chapters 2 and 3 address the impact that non-standard astrophysics and particle physics could have on the observed scattering rate in direct dark matter detection experiments; Chapter 4 presents a halo-dependent and an halo-independent update on the viability of a dark matter interpretation of the CDMS-II-Si data; Chapter 5 generalizes the halo-independent analysis formalism such that the compatibility of multiple experiments can be assessed, and the preferred halo-independent parameter space can be identified, for global likelihoods comprised of at least one extended likelihood; Chapter 6 discusses the prospects for detecting gamma-rays from dark matter annihilating in local dark matter subahlos; Chapter 7 presents updated constraints on simplified dark matter models that are consistent with the Galactic Center excess; and Chapter 8 discusses the extent to which future direct detection experiments may be able to elucidate the high-energy dark matter theory from observations of low-energy nuclear recoils.