Astrophysics Science Division Colloquium Series
Schedule: Spring 2015

Astrophysics Science Division Colloquium Series
Schedule: Spring 2015

Recent schedules:

2014, Fall 2014, Spring  
2013, Fall 2013, Spring 2013, Summer
2012, Fall 2012, Spring  
2011, Fall 2011, Spring  
2010, Fall 2010, Spring  

ASD Colloquia are Tuesdays at 3:45 pm (Meet the Speaker at 3:30 pm)
in Bldg 34, Room W150 unless otherwise noted.

January

Jan 6 AAS Meeting
Jan 13 660 Town Hall
Jan 20 NO COLLOQ (MLK)
Jan 27 Josh Shiode (AAS) - There’s Government in Your Science

February

Feb 3 Jillian Bellovary (Vanderbilt)
Feb 10 Ed Bertschinger (MIT)
Feb 17 NO COLLOQ (President's Day)
Feb 24 Vladimir Airapetian (GSFC)

March

Mar 3 Sarah Gallagher (UWO) - Winds, Winds Every Where: Radiatively Driven Outflows from Supermassive Black Holes
Mar 10 Damiono Caprioli (Princeton)
Mar 17 John Blondin (NCSU) - Dynamics of Mass Transfer and Accretion in X-ray Binaries
Mar 24  
Mar 31 Yoram Lithwick (Northwestern)

April

Apr 7  
Apr 14  
Apr 21  
Apr 28  

May

May 5  
May 12  
May 19  
May 26 NO COLLOQ (Memorial day)

There’s Government in Your Science

Josh Shiode

John N. Bahcall Public Policy Fellow, American Astronomical Society

Tuesday, Jan 27, 2015

Abstract

The majority of basic science research in the United States — including that in the astronomical sciences — is funded by the federal government. This is both good and bad. Good because there are a lot of resources available, though basic research funding is but a small fraction of the total federal budget. Bad because individual scientific projects, and the careers of the scientists involved, can be affected by political winds they would otherwise never feel. In this talk, I’ll try to convey a sense of those winds. I’ll focus on the process of policymaking and long-term trends relevant to the scientific enterprise, and we’ll explore how individual scientists and science advocates can play a role in the political and policymaking process.

Winds, Winds Every Where: Radiatively Driven Outflows from Supermassive Black Holes

Sarah Gallagher

UWO

Tuesday, Mar 3, 2015

Abstract

Supermassive black holes reside in the centers of every massive galaxy. In relatively brief spurts, black holes grow as luminous quasars through the infall of material through an accretion disk. Remarkably, the light from the accretion disk can outshine all of the stars in the host galaxy by a factor of a thousand, and this radiation can also drive energetic mass outflows. Mass ejection in the form of winds or jets appears to be as fundamental to quasar activity as accretion, and can be directly observed in many objects with broadened and blue-shifted UV emission and absorption features. A convincing argument for radiation pressure driving this ionized outflow can be made within the dust sublimation radius. Beyond, radiation pressure is still important, but high energy photons from the central engine can now push on dust grains. This physics underlies the dusty wind picture for the putative obscuring torus. I'll describe our model of the dusty wind and evaluate its successes and shortcomings in accounting for observed properties of quasars such their mid-infrared spectral energy distributions, fractions of hidden objects, and column densities of important ions.


Jeremy Schnittman
NASA Logo, National Aeronautics and Space Administration