Stars, Planets, and ISM Seminar
Sep
10
2025
Sep
10
2025
Description
Ice and Metal in the Galactic Center
JWST's suite of filters includes several that specifically target ice features, especially CO and water. We have imaged several clouds in the Galactic Center using the CO filter and found that CO ice is extremely widespread and far more abundant than expected. Drilling deep on this idea, we found evidence through photometry alone that there are peculiar ices in the Galactic center, and we show that the ice abundance can be used to measure (or at least constrain) the total metallicity of the dense star-forming material. The high ice abundance may also indicate a wildly different cosmic ray ionization rate than we have previously assumed, but this remains a work in progress. In this talk, I will cover the detailed modeling of contributions to JWST's filters, showing that we can rule out gas-phase contribution to the narrow filters and how laboratory measurements are used to estimate the ice abundance. I'll show the CO ice column density maps we've made for several clouds with 2" resolution. SPHEREX will be able to perform similar measurements on nearby clouds, but it will never match JWST's resolution and will likely be confusion-limited in the Galactic Center. Finally, I'll highlight the remaining uncertainties and how we will address them with forthcoming planned spectroscopic observations.
Other Events in This Series
Jan
15
2025
Stars, Planets, and ISM Seminar
Stars, Planets, and ISM Seminar
No meeting
12:00 pm – 1:00 pm • In Person
Jan
22
2025
Stars, Planets, and ISM Seminar
Stars, Planets, and ISM Seminar
No talk scheduled
12:00 pm – 1:00 pm • In Person
Jan
29
2025
Stars, Planets, and ISM Seminar
Stars, Planets, and ISM Seminar
Two talks by Astronomy Department graduate students
12:00 pm – 1:00 pm • In Person
Speaker(s): Nathanael Burns-Watson - The University of Texas at Austin and Carlos Jurado - The University of Texas at Austin
Feb
5
2025
Stars, Planets, and ISM Seminar
Stars, Planets, and ISM Seminar
No talk scheduled
12:00 pm – 1:00 pm • In Person
Feb
12
2025
Stars, Planets, and ISM Seminar
Special Seminar: galactic.ai — The New Frontier in Cosmology and Astrophysics
Special Seminar by ChangHoon Hahn of Princeton University
12:00 pm – 1:00 pm • In Person
Speaker(s): ChangHoon Hahn - Princeton University
Feb
19
2025
Stars, Planets, and ISM Seminar
Special Seminar: Beyond the Observable - A Machine Learning perspective on modern Cosmology
Special Seminar by Carolina Cuesta of MIT and Harvard University
12:00 pm – 1:00 pm • In Person
Speaker(s): Carolina Cuesta - MIT and Harvard University
Feb
26
2025
Stars, Planets, and ISM Seminar
Stars, Planets, and ISM Seminar
No talk scheduled
12:00 pm – 1:00 pm • In Person
Mar
5
2025
Stars, Planets, and ISM Seminar
Stars, Planets, and ISM Seminar
No talk scheduled
12:00 pm – 1:00 pm • In Person
Mar
12
2025
Stars, Planets, and ISM Seminar
Stars, Planets, and ISM Seminar
Two talks by Astronomy Department graduate students
12:00 pm – 1:00 pm • In Person
Speaker(s): Erica Sawczynec - The University of Texas at Austin and James Mang - The University of Texas at Austin
Mar
26
2025
Stars, Planets, and ISM Seminar
Stars, Planets, and ISM Seminar
Two talks by UT Astronomy graduate students
12:00 pm – 1:00 pm • In Person
Speaker(s): Malia Kao - The University of Texas at Austin and Shelby Courreges - The University of Texas at Austin