Colloquium

Physics Department Seminar

Dr. Jesse Rogerson
Canadian Aviation and Space Museum
Tuesday, December 3, 2019
15:30
HP 4351

Monitoring the Winds Generated by Super Massive Black Holes

Super massive black holes found at the centres of large galaxies are inexorably connected to the formation and evolution of their host. While actively accreting, super massive black holes create high energy jets and galactic scale winds, mechanisms surely to play at least a portion of a role in fostering this connection. Winds or outflows are manifested as broad absorption line (BAL) troughs in quasar spectra, and are measured at velocities as high as ~60,000 km s-1 at ultraviolet wavelengths. These BAL troughs have also been observed to vary on both long (years) and short (weeks) rest-frame time-scales and can both emerge in a quasar that had none, or disappear completely. By monitoring the variability of absorption in BAL quasars, constraints can be placed on the nature of outflow models, and the structure of quasars in general.

In this talk, I will discuss my recent research monitoring CIV absorption features in quasars using multiple observations from the Sloan Digital Sky Survey and Gemini Observatories. In a set of 105 quasars, BALs were detected in all but two, and a variety of absorption variability behaviour was observed. Based on this work, there is a strong signal of coordinated variability, which also scales with outflow velocity. I will also discuss our work testing two competing models of BAL variability (bulk motion and ionization changes) in the context of a case study of the quasar SDSS J023011.28+005913.6.

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