Astronomy Colloquium for 2023-02-15

Series: Astronomy Colloquium
Date: Wednesday 15-Feb-2023
Time: 16:05-17:00 (4:05-5:00 pm)
Location: ATL 2400
Speaker: Dr. Cecilla Chirenti (University of Maryland)
Title: Finding hypermassive neutron stars, or The adventures of a theoretical physicist in gamma-ray data analysis

Gamma ray bursts (GRBs) are the most luminous electromagnetic events in the universe. Short GRBs, typically lasting less than 2 seconds, have already been associated with binary neutron star (BNS) mergers, which are also sources of gravitational waves (GWs). The ultimate fate of a BNS, after coalescence, is usually expected to be a black hole (BH) with 2-3 solar masses. However, numerical relativity simulations indicate the possible formation of a short-lived hypermassive neutron star (HMNS), lasting for tens to hundreds of milliseconds after the BNS merger and before gravitational collapse forms a BH. The HMNS is expected to emit GWs that will be detectable by third generation ground-based GW detectors in the 2030s. I will present results from a recent analysis that revealed evidence for HMNSs using gamma-ray observations obtained in the 1990s with the Compton Gamma Ray Observatory.

In-person colloquia are usually preceded by espresso and ice cream at 1:45 pm outside room PSC 1150 and are followed by an informal reception at 5:15 pm in that room. Anyone interested in talking with the speaker, or being added to the colloquium announcement email list, should contact the colloquium organizer Dr. Leslie Sage. Lunch will normally be reserved for the speaker to talk to graduate students. Anyone asking a question during a talk is asked to raise their hand and be acknowledged before speaking. Contact Dr. Leslie Sage for details.

Colloquium Organizer: Dr. Leslie Sage


Special accommodations for individuals with disabilities can be made by calling (301) 405-3001. It would be appreciated if we are notified at least one week in advance.


Directions and information about parking can be found here.

This page was automatically generated on: 10-Feb-2023.