Astrophysics Seminars

Oct
06
2008

Institute for Advanced Study Informal Astrophysics Seminar - NOTE DIFFERENT DAY

Cygnus A Revisited: a Precessing Jet and Emission from Multiple Jet Activity Periods
Katrien Steenbrugge
11:30am|Bloomberg Hall Astrophysics Library
Cygnus A is the nearest powerful FR II classical double radio galaxy. We present a detailed study of this galaxy using archival radio and X-ray data. I will first show that the jet precesses, allowing us to determine an upper limit to the velocity...
Oct
02
2008

Institute for Advanced Study Informal Astrophysics Seminar

HeII Reionization and Its Effect on the IGM
Matt McQuinn
11:30am|Bloomberg Hall Astrophysics Library
Observations of the intergalactic medium (IGM) suggest that quasars reionize the HeII at z ~ 3. HeII reionization heats the IGM by tens of thousands of Kelvin, and it affects the statistics of the HI and HeII Lyman-alpha forests. I will present a...
Sep
18
2008

Institute for Advanced Study Informal Astrophysics Seminar

Observations Through a Lumpy Universe
Marilena LoVerde
11:30am|Bloomberg Hall Astrophysics Library
Weak lensing of high redshift galaxies and quasars leads to a well known adjustment of galaxy/quasar source counts called magnification bias. I will discuss how magnification bias complicates high redshift measurements of the integrated Sachs Wolfe...