Physics and Astronomy Colloquium Series

The Physics and Astronomy Colloquium Series is open to all members of the university. Unless otherwise noted, talks are held on Thursday afternoons at 4:00-5:20 in Mendocino 1015 during the Fall and Spring semesters. Schedule is regularly updated as dates, titles, and abstracts are received. Please check back often. To receive updates about the Colloquium Series, please join our Events Mailing List. For past semesters' series, see our archive.

Fall 2018 Semester Schedule

August 30, 2018
Dr. John Gillaspy

National Science Foundation
"How NOT to get a grant from NSF"

September 20
Prof. Helene Flohic
University of the Pacific
Observations of Supermassive Black Holes in Transition States

Friday, October 5
Natural Sciences and Mathematics Research Symposium
University Union Ballroom III
5:00PM - 7:00PM

October 11
Prof. Rae Robertson-Anderson
University of San Diego
Topic: Biophysics

October 25
Dr. Laura McWilliams
California State Senate, Energy Policy Committee
Topic: Science Policy

November 1
Prof. Derek Kimball
California State University, East Bay
Topic: TBA

November 15
Dr. Tammy Ma
Lawrence Livermore National Lab
Topic: National Ignition Facility

November 29
Sacramento State Physics Majors
"Senior Project Talks"

December 6
Sacramento State Physics Majors
"Senior Project Talks"

 

 

Next Seminar

September 20, 2018
Prof. Helene Flohic
University of the Pacific

Observations of Supermassive Black Holes in Transition States

Abstract:

Matter falling towards supermassive black holes forms accretion disks that are among the brightest objects in the Universe. Depending on the accretion rate of matter, these disks may be geometrically thin or thick, more or less dense, and with vastly different spectra and time variability patterns. While studies are uncovering the fine structure of the disk in each accretion state, it is still unclear how the disk transitions from one state to the other. Recent observations of quickly varying quasars, in particular, have surprising implications for the timescale of the transition. I will present an overview of what we know (and how we know) about the structure of the disk in the high and low accretion states. Then I will present the recent observations of rapidly varying quasars and discuss their significance for the field.