2021
Outreach event: Mapping the Origins of the Universe
3:30–4:30 pm Zoom
Join C2ST as we connect with researchers LIVE from the NSF-funded telescope projects in the South Pole and Chile to unlock some great mysteries to the origin of the cosmos.
KICP Seminar: Anna-Christina Eilers (MIT)
12:00–1:00 pm Zoom
Anna-Christina Eilers, MIT, “The Formation and Growth of Supermassive Black Holes”
A&A Colloquium: Kareem El-Badry (University of California, Berkeley)
3:30–4:30 pm Zoom
“Better together: binary stars as probes of stellar evolution and fundamental physics”
Binary stars are foundational to modern astrophysics. They underpin precision measurements of stellar structure, age, and composition; they provide the most stringent tests of general relativity, they make possible the study of faint and rare objects such as black holes and neutron stars, and they are the progenitors of gravitational wave sources. The components of binaries often interact, dramatically changing their evolution and giving rise to a spectacular zoo of astrophysical phenomenology. To understand stars—particularly massive stars—it is necessary to understand binaries. Large-scale stellar surveys such as Gaia, TESS, and SDSS-V are transforming the binary field, making possible both comprehensive population demographics and the discovery of rare objects. I will discuss new insights gleaned from surveys in recent years, including the creation of stripped-envelope stars following binary mass transfer, the formation of equal-mass “twin” binaries in circumbinary disks, the metallicity-dependence of the binary fraction, and the discovery of planets in binaries. I will focus in particular on the search for dormant stellar-mass black holes in binaries, discussing recent candidates and the path forward to characterizing the detached black hole population.
Tuesday Lunch Seminar: Vikram Dwarkadas (UChicago)
12:00–1:00 pm Zoom
Triggered Star Formation Inside the Shell of a Wolf–Rayet Bubble as the Origin of the Solar System
Vikram Dwarkadas, UChicago
KICP Seminar: Suhail Dhawan (Stockholm/KICC, Cambridge)
12:00–1:00 pm Zoom
Suhail Dhawan, Stockholm/KICC, Cambridge, “Cosmology with Type Ia Supernovae: A View from the Zwicky Transient Facility”
A&A Colloquium: Anna Rosen (Harvard)
3:30–4:30 pm Zoom
The Destructive Birth of Massive Stars and Massive Star Clusters
Massive stars play an essential role in the Universe. They are rare, yet the energy and momentum they inject into the interstellar medium (ISM) with their intense radiation fields and fast, isotropic radiatively driven winds dwarfs the contribution by their vastly more numerous low-mass cousins. This stellar feedback dominates the energy and momentum budget in star-forming regions and galaxies leading to gas ejection, which has important implications for star and galaxy formation. Massive stars form from the gravitational collapse of magnetized, dense, and turbulent molecular gas in massive pre-stellar cores, which are located in highly embedded environments. During their formation, feedback from their intense radiation fields, collimated protostellar outflows, and stellar winds can limit their growth by accretion. In this talk, I will show a series of radiation-magnetohydrodynamic (RMHD) simulations of the collapse of massive pre-stellar cores into massive stellar systems that include these feedback processes to demonstrate how stellar feedback can limit accretion onto massive stars and disrupt their natal environments. In addition, I will also discuss how stellar feedback from massive stars, which are born in clustered environments, affects the dynamics of HII regions that surround these clusters and can drive ISM turbulence in young, star clusters. Finally, I will talk about the future of state-of-the-art RMHD simulations with the new “Star Formation in Gaseous Environments” (STARFORGE) framework that will study the formation of star clusters from the gravitational collapse of giant molecular clouds by including all of the relevant stellar feedback processes and are capable of resolving the formation of individual stars. Such simulations will facilitate unprecedented strides in our understanding of the importance of stellar feedback in star formation and to determine how the interaction of stars in gaseous environments affects stellar dynamics, clustering, and ejection of stars.
KICP Seminar: Giuseppe Puglisi, (University of California, Berkeley)
12:00–1:00 pm Zoom
Giuseppe Puglisi, University of California (Berkeley), “Extending Galactic Foreground Mmodels for CMB with Adversarial Networks”
KICP Colloquium: Eduardo Rozo (University of Arizona)
3:30–4:30 pm Zoom
Eduardo Rozo, University of Arizona, “Unlocking Halo Dynamics as a Guiding Principle for Modeling Large Scale Structure”
KICP Seminar: Yun-Ting Cheng (Caltech)
12:00–1:00 pm Zoom Room
Yun-Ting Cheng, Caltech, “Cosmology and Astrophysics with Intensity Mapping”
A&A Colloquium: Claude-André Faucher-Giguere (Northwestern)
3:30–4:30 pm Zoom - for link, please contact, Laticia
“How do galaxies form? New insights from FIRE and into the role of the circumgalactic medium”
Abstract: Galaxies are remarkably diverse in their properties, ranging from irregular to disky to elliptical in morphology, and from blue to red in color. At the same time, when analyzed systematically, galaxy populations exhibit striking regularities, with clear trends with mass and redshift. How does this “regular complexity” emerge from the hot Big Bang? I will present results from the FIRE simulations which shed some light onto the processes that shape galaxies. The FIRE zoom-in simulations resolve the multiphase interstellar medium of galaxies and model several different feedback processes (including Type II/Ia supernovae, stellar winds, and radiation) while including the cosmological environment. I will highlight recent results on the formation of disk galaxies, the “burstiness” of star formation, and galactic winds. Our new results indicate that transitions in each of these important phenomena can be simultaneously explained by a phase transition in the inner circumgalactic medium, “inner CGM virialization” (ICV), and arise from the interplay between feedback energy produced on small scales and the physics of halo gas on larger scales.