Description:

Title:  The Stellar Ultrasound: How Asteroseismology Revolutionized Our
Understanding of Stellar Interiors

Speaker: Matteo Cantiello, Kavli Institute for Theoretical Physics

Host: Sourav Chatterjee

Abstract: Internal rotation and magnetism are key ingredients that largely affect explosive stellar deaths (Supernovae and Gamma Ray Bursts) and the properties of stellar remnants (White Dwarfs, Neutron Stars and Black Holes). However, the study of these subtle internal stellar properties was limited to very indirect proxies. In the last couple of years, new exciting asteroseismic results have been obtained by the Kepler satellite. Among these results are 1) the direct measure of the degree of radial differential rotation in many evolved low-mass stars, and 2) the detection of strong (>10^5 G) internal magnetic fields in the cores of thousands of red giant stars. I will explain how asteroseismology is able to probe rotation and magnetism in the internal regions of red giant stars. I will then show how these asteroseismic observations can now be used to test different mechanisms for angular momentum transport and to study the evolution of internal magnetism in stars. I will conclude with a brief discussion of the important consequences of these recent discoveries.

Keywords: Physics, Astronomy, Astrophysics