FLASH Talks: Hot Jupiters, Magnetic Drag, and the Need for 3D Atmospheric Models (Hayley Beltz) & Gourav Khullar (University of Chicago)

Friday, 05 November 2021 noon — 1 p.m. MST

Hayley Beltz (University of Michigan) & Synthesizing Stellar Populations in Massive Galaxy Clusters and High-Redshift Lensed Galaxies (Gourav Khullar)
Hayley Beltz, University of Michigan
Hot Jupiters, Magnetic Drag, and the Need for 3D Atmospheric Models 
With the introduction of high resolution spectroscopy (R~100,000), astronomers are sensitive to a new realm of atmospheric characterization of hot and ultra-hot Jupiters. These planets are expected to be locked in tidally synchronous orbits due to their short orbital periods. This results in strong temperature and chemical gradients across the planet from the dayside to the nightside. In this talk, I discuss my work with 3D atmospheric models of hot and ultra hot Jupiters and how 3D effects show up in observational data. I additionally discuss our locally calculated magnetic drag prescription and its effects on atmospheric circulation of these planets. With this talk, I hope to impart the usefulness and necessity of complex, multi-dimensional models when interpreting high resolution observational data. 
Gourav Khullar,  Kavli Institute for Cosmological Physics (KICP)
Synthesizing Stellar Populations in Massive Galaxy Clusters and High-Redshift Lensed Galaxies
In this talk, I describe my work to characterize stellar populations in massive galaxies at two epochs — redshifts ~0.5 and ~5. I use spectra of galaxies in South Pole Telescope galaxy clusters to address the question: on what timescales do galaxies that end up in clusters form their stars, and does the cluster sample matter when studying these properties? We use a mass-limited cluster sample across 0.3 < z < 1.5 to constrain star formation histories and formation redshifts of 900 quiescent galaxies in clusters, as a function of cluster environment and mass. This study explores mass-dependent evolution in cluster quiescent galaxies and characterises galaxy evolution across a descendent-antecedent cluster sample.

On the other ‘end’ of the redshift scale, I will share the characterization of COOL J1241+2219, a lensed galaxy at z = 5.04 that is the brightest galaxy known at z > 5 (zAB ~ 20.5). This galaxy was discovered by COOL-LAMPS — ChicagO Optically-selected strong Lenses - Located At the Margins of Public Surveys — initiated to find strongly lensed systems, consisting primarily of a team of undergraduate students. We characterize the lensed galaxy using ground-based spectrophotometric data to find an intrinsically luminous and massive star-forming galaxy. We aim to compare CJ1241 and other COOL-LAMPS discovered lensed massive galaxies at z>3 with their potential descendents — quiescent massive galaxies at lower redshifts. With anticipated multi-wavelength spectroscopic data, including from an approved JWST Cycle 1 Program (GO 2566, PI: Khullar), we will uncover mass assembly pathways in CJ1241 well into the epoch of reionization.

Join us on this Zoom channel:  https://noirlab-edu.zoom.us/j/95030775076?pwd=Mm4rTXJCN0E3aVA5MDFSckY0RWRjdz09 

FLASH Talks are scientific talks for the staff at NOIRLab and the University of Arizona's Steward Observatory.