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Journal Club Seminars

Contents

The Journal Club talks take place on Fridays from 12:00 - 1:00pm in SERF 383. Generally pizza and soda are served.

The Journal Club is crafted to be a very informal and friendly environment where graduate students can present talks on any subject of interest to them, be it a recent journal paper, their own research work, or any topic.

Everyone is welcome to attend.

If you are interested in giving a talk, please contact: Amol Patwardhan

Past journal club talks are listed in the sidebar by year.

Upcoming Journal Club Seminars

Spring 2017


April 28, 2017

 "r-Process Nucleosynthesis in Quark-Novae"

Kelsey Lund (12:00-12:30)
Physics Undergraduate Student
UCSD-CASS
OPEN TIME SLOT (12:30-1:00)



May 5, 2017

 "Fading active galaxies, feedback, and the demographics of growing
black holes"

Bill Keel (12:00-1:00)
Professor
University of Alabama

 Roughly 1/1000 of nearby active galactic nuclei (AGN), and a larger fraction of AGN with tidal features in stars or cool gas, are accompanied by extended emission-line regions on scales 10 kpc and larger (beyond the normal interstellar medium of the host galaxy). In about 40% of these, the AGN falls short of the energy budget needed to photoionize these clouds by 1-3 orders of magnitude, implying that the AGN have faded over the relevant light-travel times. All these are in interacting or postmerger systems, possibly needed for sufficient distant, cold neutral hydrogen to trace the AGN's ionization history. In many of the fading candidates, low abundances and quiescent kinematics indicate that we see photoionized gaseous debris from tidal interactions, rather than outflowing material; separate signatures of sub-kiloparsec outflows are seen in some cases, giving an intriguing hint that the mode of energy output incidental to accretion (and thus the dominant source of feedback to the surrounding material) may be changing, and not just the accretion rate itself. Luminosity histories derived from recombination balance show e-folding timescales from centuries to a few millenia, short compared to simple accretion-disk expectations. These rapid, large-amplitude changes may be associated with supermassive black holes in binary systems or with local feedback processes. These results suggest that the demographics of accreting supermassive black holes are broader than derived from surveys of ongoing AGN signatures alone, a conclusion supported by new samples of analogous objects in both very nearby and moderate-redshift systems. These discoveries have been an important byproduct of citizen engagement in the Galaxy Zoo project.



May 12, 2017

 Title: TBA

Tucker Elleflot (12:00-12:30)
Physics Graduate Student
UCSD-CASS
OPEN TIME SLOT (12:30-1:00)



May 19, 2017

 Title: TBA

Nick Colmenares (12:00-12:30)
Physics Graduate Student
UCSD-CASS
OPEN TIME SLOT (12:30-1:00)



May 26, 2017

 Title: TBA

JT Li (12:00-12:30)
Physics Graduate Student
UCSD-CASS
OPEN TIME SLOT (12:30-1:00)

June 2, 2017

TK's Title: Title: TBA
I-Da's Title: Title: TBA

TK Chan (12:00-12:30)
Physics Graduate Student
UCSD-CASS
I-Da Chiang (12:30-1:00)
Physics Graduate Student
UCSD-CASS