Astronomy and Astrophysics Seminars

Cosmology with Type Ia Supernovae: A view from the Zwicky Transient Facility

by Dr. Suhail Dhawan (University of Cambridge)

Tuesday, March 16, 2021 from to (Asia/Kolkata)
at Zoom link ( https://zoom.us/j/98259046946?pwd=WDFzMXJacDAyL0VNRmNvdUpGRFpPUT09 (Meeting ID: 982 5904 6946 Passcode: Sem16Mar21) )
Meeting ID: 982 5904 6946 Passcode: Sem16Mar21
Description
Type Ia supernovae are magnificent stellar explosions that play a starring role in modern cosmology. In the local universe, they can be calibrated to infer the Hubble constant, which is in tension with the value inferred from the early universe. The Hubble tension is one of the most exciting unsolved puzzles in modern cosmology. Moreover, distant Type Ia supernovae have been developed as precision probes of acceleration expansion and are critical to understand the nature of dark energy. 

In my talk I will present recent studies on potential causes of the Hubble tension, the role of dark energy model assumptions and potential astrophysical systematics. I will discuss ongoing work with the Zwicky Transient Facility, to build a large sample of SNe Ia from a single, untargeted survey. In context of ZTF, I will also describe previous and ongoing searches for lensed Type Ia supernovae a completely independent probe of the Hubble constant with interesting applications to explore theories of gravity and study high-redshift sources. 

In addition to constraints on the expansion history, I will present ongoing work on using SNe Ia as a probe for local large scale structure and how the ZTF sample helps understand local bulk flows.