Events Daily

Tuesday, March 7, 2023

Event Type: Other
Time: 10:30 AM - 11:30 AM
Location: 726 Broadway, 901, Sm Conf

Astro Journal Club
Event Type: Other
Time: 12:30 PM - 1:30 PM
Location: 726 Broadway, 940, CCPP Seminar

On stars as tools to reconstruct the history of the Milky Way
Melissa Ness, Columbia University
Event Type: Astro Seminar
Time: 2:00 PM - 3:15 PM
Location: 726 Broadway, 940, CCPP Seminar
Abstract: Galactic archaeology has entered a remarkable era, with Gaia and an ensemble of spectroscopic surveys providing element abundances and velocities for millions of stars. With the dramatic increase in data, there is an opportunity to understand its limitations: how can this data actually inform our Galactic history? I will show some of the limitations (and opportunities) in using stellar spectra and derived element abundances for unravelling galactic history in the disk: 1 in 100 stars in high-resolution IR surveys of the disk are doppelgangers - identical but unrelated - impeding the prospect of so-called "chemical tagging" with these data. Furthermore, many individual element abundances can be predicted to a precision of ~0.015 dex, given only three measurements; two abundances, for elements produced in type Ia and II supernovae, and age Such limitations frame how we can most effectively work with the data, to turn photons into a quantified description of Galactic history.