Past Colloquia
Multi-messenger Hunt for Galactic PeVatrons
Cody Hall
Shuo Zhang, Michigan State University
December 11, 2024
2:00pm - 3:00pm
Abstract: Cosmic rays with energies up to a few PeV are believed to originate from our own galaxy. However, the origin of Galactic cosmic rays has remained a mystery for over a century since their discovery. Recent breakthroughs in neutrino and gamma-ray astronomy have provided…
It’s Raining Black Holes… Hallelujah!
Prof. Smadar Naoz. UCLA
December 04, 2024
2:00pm - 3:00pm
Abstract: The groundbreaking detection of gravitational waves from merging black holes has forever changed how we observe the Universe. Upcoming detectors, like the Laser Interferometer Space Antenna (LISA), will unlock new opportunities by allowing us to detect mergers between stellar-mass black holes (tens of solar…
Gravitational Lens Reveals Surprising Aspects of Newborn Super Star Cluster
Cody Hall
Prof. Liang Dai, UC Berkeley
November 27, 2024
2:00pm - 3:00pm
Abstract: Gravitational magnification by foreground galaxy clusters has provided us with the rare opportunity to witness star formation taking place in distant galaxies and under conditions that are among the most extreme throughout the Universe. Gravitating gas weighing millions to tens of millions of solar masses…
The Fates of Stars Orbiting too Close to Massive Black Holes
Cody Hall, 50 St. George Street
Prof. Quateart
November 20, 2024
2:00pm - 3:00pm
Abstract: Stars orbiting sufficiently close to massive black holes inevitably inspiral towards the black hole due to gravitational wave radiation. The fate of such stars is subtle and depends on an interplay between tidal heating of the star, mass transfer from the star to the…
Dwarf galaxy science with Euclid
Cody Hall, 50 St. George Street
Francine Marleau, University of Innsbruck.
November 13, 2024
2:00pm - 3:00pm
Abstract: The unprecedented low surface brightness sensitivity, high spatial resolution with pristine PSF, and wide-area coverage of Euclid opens up a completely new avenue in the combined investigation of a vast number of low surface brightness dwarf galaxies, their nuclear star clusters as well as…
The Needles and Hay: Leveraging the Supernova Treasuretrove of the Rubin Observatory
Cody Hall, 50 St. George Street
Prof. Ashley Villar, Harvard University
November 06, 2024
2:00pm - 3:00pm
Abstract: The eruptions, collisions and explosions of stars drive the universe’s chemical and dynamical evolution. The upcoming Legacy Survey of Space and Time will drastically increase the discovery rate of these transient phenomena, bringing time-domain astrophysics into the realm of “big data.” With this transition…
The growth of supermassive black holes is dominated by galaxy merger-free processes
Cody Hall, 50 St. George Street
Rebecca Smethurst, Oxford University
October 23, 2024
2:00pm - 3:00pm
Abstract: The strong correlations that are found between supermassive black hole (SMBH) mass and velocity dispersion, stellar mass and bulge mass have long been interpreted as co-evolution of galaxies and their SMBHs through galaxy mergers. However, a flurry of new results, both observational and theoretical, have suggested…
It Takes Two to Tango: Modeling Binary Stellar Populations in the Gravitational Wave Era
Cody Hall, 50 St. George Street
Prof. Jeff Andrews, University of Florida
October 16, 2024
2:00pm - 3:00pm
Abstract: Between the discovery of gravitational waves from over a hundred merging compact objects and the advent of micro-arcsecond astrometry realized by the Gaia space telescope, the study of the complexities of binary stellar evolution – including mass transfer, tides, and r-process nucleosynthesis – has…
“Stellar Tides: A Travelogue”
Cody Hall, 50 St. George Street
Prof. Richard Townsend, University of Wisconsin-Madison
October 09, 2024
2:00pm - 3:00pm
Abstract: The majority of my scientific career has focused on the study of stellar oscillations — standing and traveling waves that cause periodic perturbations to the internal structure and surface properties of stars. In the past few years, however, I’ve become fascinated by the phenomenon…
Multi-wavelength Observations of Variable Plasmas at the Event Horizon
Cody Hall, 50 St. George Street
Daryl Haggard, McGill University
October 02, 2024
2:00pm - 3:00pm
Abstract: Observational studies of black holes have progressed by leaps and bounds over the last two decades, advanced by a wealth of new instruments and analysis techniques. I will discuss the unique variability of Sagittarius A* (Sgr A*), the Milky Way’s supermassive black hole, alongside…