SUNY Geneseo Physics & Astronomy Colloquium

Thursdays, 4:00 p.m., in Newton 204. (There will be refreshments!)

(See Colloquia List for the Full Semester)

Extragalactic dust and how it affects observations of galaxies across cosmic time

by Alexander Belles, Ph.D. Candidate

Penn State University


Thursday April 25, 2024 

at 4:00 pm in Newton 204

Abstract: Ultraviolet radiation traces recent star formation in galaxies. However, intervening material within galaxies, called interstellar dust, obscures and reddens the light that we observe. In order to accurately estimate galaxy properties such as star formation rate and stellar mass, the effects of dust must be accounted for. By fitting UV through IR photometry of galaxies, the wavelength dependent effects of dust in other galaxies can be inferred alongside other galaxy properties. In this talk, I will describe near UV observations of galaxies using the Ultraviolet Optical Telescope aboard the Neil Gehrels Swift Observatory. I will explore the star formation and dust properties of nearby galaxies and how uncertainty in the dust correction complicates determining the star formation rate density evolution during the era of peak star formation. I will discuss how a variety of factors, including modeling assumptions, sample selection, and data availability, can complicate disentangling the effects of dust and the physics of stellar populations.