Astrophysics

Abstract: In this talk I will focus on light dark matter particles, with a mass between 1 MeV and a few GeV. These particles can annihilate or decay into electron-positron pairs which can upscatter the low-energy fields in our Galaxy and produce X...

Fast and Blue Optical Transients (FBOTs) emerged in the past decade as a new class of astronomical transients. With extremely rapid time scales of evolution and luminous emission, FBOTs likely probe the extremes of the explosion parameters and/or...

After the landmark neutron-star merger event GW170817, the frontier is now to map the properties of a population of neutron star mergers, find electromagnetic counterparts of NS-BH mergers, and connect the pre-merger to the post-merger properties of...

This talk will present the first results of the MIRI-MRS spectra of a number of protostars, T Tauri and brown dwarf disks resulting from the JOYS and MINDS GTO programs. Rich ice spectra are seen in the cold outer envelopes of protostars hinting at...

Fast inward migration of planetary cores embedded in gaseous disks is a common problem in the current planet formation paradigm. Even though dust is ubiquitous in protoplanetary disks, its dynamical role in the migration history of planetary embryos...

The Bahcall Lunch follows the astrophysics colloquium lecture. 

Astronomical transients are signposts of catastrophic events in space, including the most extreme stellar deaths, stellar tidal disruptions by supermassive black holes, and mergers of compact objects. Thanks to new and improved observational...

Abstract: I give new results for "gravastars'', which are horizonless compact objects that closely mimic mathematical black holes in their exterior geometry,  but for which g_{00} is always positive.  They result from  solving the  Tolman...