Title: Discovering axions with novel astrophysical observations
Abstract: Axions are some of the best-motivated beyond the Standard Model particle candidates at present. These ultralight particles may account for the cosmological dark matter and explain other outstanding problems in nature, such as the strong-CP problem; they also are now known to emerge generically in string theory. Axions are expected to couple ultra-weakly with ordinary matter, and many of the most promising avenues for detecting axions rely on astrophysical observations of extreme systems that are able to magnify these feeble interactions. In this talk I will give a broad overview of the landscape of axion detection efforts, with a specific focus on those using astrophysical data sets. For example, I will discuss compact stars as axion laboratories, in the contexts of magnetic white dwarf optical polarization, novel radio and X-ray signatures, and possible gamma-ray signals from future supernovae. I will conclude by commenting on some of the remaining outstanding challenges in the effort to detect or rule out axions.