Title: Astrophysical Probes to New Physics Beyond the Standard Model

Speaker: Yue Zhao (University of Utah) 

Time: 16:00pm, Dec. 10 (Thursday)

Location: Hall 212, Astronomy Building

Abstract: Particle physics research can significantly deepen people's understanding about the elementary building blocks and fundamental laws of nature. The Standard Model of particle physics provides the foundation of modern high energy physics. However, the Standard Model fails miserably in several aspects. First, it has no dark matter candidate. Further, there are a few super tiny parameters, such as the strong CP phase, which remains to be explained. Both aspects point to the existence of new physics beyond the Standard Model. In this talk, I will present two novel ways utilizing astrophysical observations to probe the existence of new physics. I will first talk about how to use the Gravitational Wave experiments, i.e. LIGO and LISA, to search for ultra-light dark photon dark matter. Using LIGO's data, our result sets the world record on the unexplored parameter space. Then I will demonstrate that, with high spatial resolution, polarimetric imaging of a supermassive black hole by the Event Horizon Telescope can be used to probe the existence of axions. Through these two example, we show that a nice bridge can be built between astrophysics and particle physics, and interesting particle physics questions can be answered by powerful astrophysical probes.