Scratching Below The Surface Of White Dwarfs: Equation Of State Measurements At Unprecedented Pressures

Presentation #302.04 in the session “Laboratory Astrophysics Division (LAD): Fundamental Nuclear and Atomic Data for Compact Objects”.

by D. Saumon, S. Blouin, T. Doeppner, R. Falcone, S. Glenzer, A. Kritcher, A. Lazicki, M. MacDonald, B. Militzer, D. Swift, and H. Whitley

Published onJun 18, 2021

We have started a program to measure the equation of state of shock-compressed carbon and oxygen with the new Gbar platform at the National Ignition Facility (NIF), the world’s highest energy laser. By reaching pressures of ~10¹⁵ dyn/cm² (10⁹ bar) and temperatures of a few 10⁶ K (100 eV), it is now possible to probe the regime of partial ionization of dense carbon and oxygen, where the equation of state is rather uncertain theoretically and untested by experiments. The new measurements will constrain theoretical models and tables of the equation of state of carbon and oxygen in a regime that is critical to understand several phenomena in white dwarfs.