Series: Astronomy Colloquium
Date: Wednesday 26-Feb-2025
Time: 16:05-17:00 (4:05-5:00 pm)
Location: ATL 2400
Speaker: Dr. Kartheik Iyer (Columbia University)
Title: Reading stories written in starlight: Understanding what shaped the past lives of galaxies with novel astrostatistical methods
The light from galaxies that we observe with telescopes on the ground and in space contains emission from its component stars, gas and dust. The spectra (or spectral energy distributions; SEDs) of galaxies therefore tell us stories of how galaxies form and evolve over time, and help us understand the complex processes that regulate galaxy growth over vastly different spatial and temporal scales. Modern galaxy surveys have observed millions of galaxies (and counting!) with unprecedented sensitivity across a wide range of wavelengths, enabling the reconstruction of galaxy star formation histories (SFHs). Meanwhile, large cosmological hydrodynamical simulations help us connect the physical processes that shape galaxies (cosmological accretion, feedback and baryon cycling, mergers, and more) to the imprints they leave in galaxy SFHs. My research focuses on building a new temporal picture of galaxy evolution by developing novel mathematical frameworks and computational tools to extract information from observations and connect them to theoretical models. I will discuss how this work (i) has led to the development of new methods and data products (Dense Basis, GP-SFH, Katachi) that are valuable to the wider scientific community, (ii) is being applied to observations from JWST, leading to exciting discoveries about how galaxies form stars in the early universe, and (iii) will address the unique challenges (and opportunities!) posed by large, noisy datasets from upcoming observations. While it is always an exciting time to be an astronomer, recent advances in the adjacent fields of astrostatistics and machine learning have opened up new windows for us to identify subtle signals in large populations of galaxies. As we prepare for the next generation of astronomical facilities, these methods - and the interdisciplinary approaches they represent - will be crucial for understanding how galaxies like our Milky Way came to be.
In-person 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 Dr. Richard Mushotzky. 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. Contact Dr. Richard Mushotzky for details.
Colloquium Organizer:
Dr. Richard Mushotzky
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.
