Series: Astronomy Colloquium
Date: Wednesday 26-Feb-2020
Time: 16:05-17:00 (4:05-5:00 pm)
Location: ATL 2400
Speaker: Dr. Ilse Cleeves (University of Virginia)
Title: Illuminating the Chemistry of Planet Formation with X-ray Flares
The chemistry of protoplanetary disks sets the initial composition of newly formed planets and may also regulate the efficiency by which planets form. Disk chemical abundances typically evolve over timescales spanning thousands if not millions of years. Consequently, it was a surprise when ALMA observations taken over the course of a single year showed significantly variable molecular emission in H13CO+ relative to the otherwise constant thermal dust emission in the IM Lup protoplanetary disk. HCO+ is a known X-ray sensitive molecule, and one possible explanation is that stellar activity is perturbing the chemical "steady state" of the disk. If confirmed, simultaneous observations may provide a new tool to measure (and potentially map) fundamental disk parameters, such as electron density, as the light from X-ray flares propagates across the disk.
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. 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.
Colloquium Organizer:
Prof. Richard Mushotzy
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.
