Past Colloquia
Imaging the Invisible with the Little Canadian Radio Telescope that Could
Cody Hall
Jo-Anne Brown (University of Calgary)
November 27, 2015
14:00 - 15:00
Magnetic fields are an important constituent in the interstellar medium, but unlike gas, dust, and cosmic rays, they do not radiate, and consequently cannot be observed directly. Instead, observers identify signatures of the field in an effort to piece together its topology. Determining the structure of…
Constraining the Physics of Satellite Quenching
Cody Hall
Mike Cooper (University of Californina Irvine)
November 20, 2015
14:00 - 15:00
Despite remarkable success at modeling the evolution of massive galaxies over cosmic time, modern hydrodynamic and semi-analytic models of galaxy formation fail to reproduce the properties of low-mass galaxies. This shortcoming in our theoretical picture is largely driven by an inability to understand the physics…
Tides and the interior structure of the Moon and icy satellites
Cody Hall
Isamu Matsuyama (LPL/Arizona)
November 13, 2015
14:00 - 15:00
The interior structure of a satellite determines its response to rotational and tidal forcing, which in turn affects its equilibrium shape and tidal heating. The unusual shape of the Moon given its present rotational and orbital state has been explained as due to a fossil…
Globular Cluster Systems, Galaxy Halos, and Dark Matter
Cody Hall
Bill Harris (McMaster University)
November 06, 2015
14:00 - 15:00
We’ve known for 30+ years that galaxies are embedded in dark-matter halos that dominate their total mass. But it has been difficult to find any visible stellar population that correlates in a simple way with DM halo mass. Systems of globular clusters have now been…
Coevolution (Or Not) Of Supermassive Black Holes And Host Galaxies
Cody Hall
John Kormendy (University of Texas)
October 23, 2015
14:00 - 15:00
I review the observed demographics and inferred evolution of supermassive black holes (BHs) found by dynamical modeling of spatially resolved kinematics. Tight correlations between BH mass and the mass and velocity dispersion of the host-galaxy bulge have led to the belief that BHs and bulges…
The Social Network Outburst: A Multiwavelength perspective on the 2015 V404 Cyg Outburst
Cody Hall
Greg Sivakoff (University of Alberta)
October 16, 2015
14:00 - 15:00
Accretion disks and jets are ubiquitous astrophysical phenomena. Given the potential feedback between supermassive black holes and galaxy evolution, understanding the physics of accretion discs and relativistic radio jets around Active Galactic Nuclei (AGN) has gained increased motivation; however, the outbursts of AGN likely last…
Tracking Planet Footprints in Dusty Disks
Cody Hall
Catherine Espaillat (Boston University)
October 09, 2015
14:00 - 15:00
We know that most stars were once surrounded by protoplanetary disks. How these young disks evolve into planetary systems is a fundamental question in astronomy. Observations of T Tauri stars (TTS) may provide insights, particularly a subset of TTS with “transitional disks” that contain holes…
Central galaxies and their satellites out to z~2
Cody Hall
Ryan Quadri (Texas A&M University)
October 02, 2015
14:00 - 15:00
The mysterious lack of star formation in a substantial fraction of the galaxy population over a wide range in both mass and redshift has been the subject of much discussion over the years. We can gain information about the quenching processes that operate specifically on…
The Panchromatic Hubble Andromeda Treasury: 0.1 Billion Stars, and Lots and Lots of Dust
Cody Hall
Julianne Dalcanton (University of Washington)
September 25, 2015
14:00 - 15:00
Abstract: The Panchromatic Hubble Andromeda Treasury is an HST multicycle program to image the north east quadrant of M31 to deep limits in the UV, optical, and near-IR. The HST imaging has resolved the galaxy into over 150 million stars (comparable to ~1/2 the number…
Probing the Secrets of Supernovae through their Spectra and Light Curves
Cody Hall
John Hillier (University of Pittsburgh)
September 18, 2015
14:00 - 15:00
The discovery of thousands of supernovae (SNe) by modern survey telescopes is allowing us to define the statistics of SN occurrence as a function of class and host galaxy properties, and is helping to facilitate the direct identification of SN progenitors. Further, we are able…