AUGUST MEETING via ZOOM (ID & Password Required)
Saturday, August 1, 2020 at 7 PM
Topic: "Uncovering the Nature of Dark Matter with Stellar Streams in the Milky Way"
Speaker: Ana Bonaca, Fellow at the Institute for Theory and Computation, Harvard-Smithsonian Center for Astrophysics
Globular clusters are large congregations of stars, which gradually lose their members to form thin and long stellar streams. In pristine conditions, these streams have a nearly uniform density, however, new observations of one such structure in the Milky Way halo have revealed a likely site of perturbation. The on-sky morphology suggests a recent, close encounter with a massive and dense perturber. Known baryonic objects are unlikely perturbers based on their orbital properties, but observations permit a low-mass clump of dark matter as a plausible candidate. This discovery opens up the exciting possibility that detailed observations of streams could measure the abundance of dark-matter substructure and thus shed light on the nature of dark matter.
Ana Bonaca is a Fellow at the Institute for Theory and Computation, hosted by the Center for Astrophysics | Harvard & Smithsonian. She works on creating a 3D, high-resolution map of the Milky Way halo, which is dominated by the elusive dark matter. In her research, she collects and employs data from ground- and space-based observatories, analyzes numerical simulations and develops new statistical tools. Ana obtained an Astronomy PhD from Yale University and was awarded the Brouwer prize for a distinguished thesis.
Date: Saturday, 8/1/2020
Time: 7:00 PM - 8:30 PM Eastern