Sorry, you need to enable JavaScript to visit this website.

Site-wide links

Astro Lunch Talks

Astro Lunch Talks
Wednesdays, 11:45am-1:00pm, 76-1275 Carlson Learning Center.
Topics will be emailed prior to the talk. Please contact Ben Sargent for more information. 
 
Upcoming Talk Details
Date/Time: December 3, 12:00pm 76-1275
 
Speaker: Sukanya Chakrabarti
TITLE:  Clustered Cepheid variables in Norma:  a distant dwarf galaxy in the plane of the Milky Way

ABSTRACT:Of the known Milky Way satellites, the Sagittarius dwarf galaxy is closest to the plane of the Milky Way, about 14 degrees in latitude from the disk of our Galaxy 1. The dearth of Milky Way satellites at low latitudes is underscored by simulations that suggest that there may be massive, nearly dark satellites that have not yet been discovered.  I will report the identification of fourteen Cepheid variables within an angular extent of ~ three degrees centered at Galactic coordinates (l, b = −27.4◦, −0.68◦) from the analysis of near-infrared data (that minimizes dust obscuration) from the ESO Public survey VISTA Variables of the Via Lactea (VVV). The tightly constrained period-luminosity relationship that these pulsating stars obey can be used to derive accurate distances. We infer an average distance to these Cepheid variables of ~ 100 kiloparsec from the Galactic center. These young stars are unexpected at such large distances from the Galactic disk, which terminates at ~15 kiloparsec. We also see an excess in the spatial distribution of distant red-clump giants at the same longitudes. These observations suggest that the stars may be associated with a predicted dwarf galaxy (Chakrabarti & Blitz 2009; Chakrabarti & Blitz 2011), located behind the Galactic disk, containing recently formed stars more distant than the Large Magellanic Cloud but nearer than Andromeda.


2014-2015 Academic Year Scheduled Dates
Date Speaker Title
8/20/2014
Yasaman Yazdi
Firewall Phenomenology with Astrophysical Neutrinos
9/3/2014
Adrian Hamers
Secular dynamics of hierarchical quadruple systems
9/17/2014
Andy Lipnicky
Exploring the Effects of Dwarf Galaxies on HI Disks
9/19/2014
Dennis Bowen
Simulating Binary Black Holes in their Astrophysical Environment
9/24/2014
Triana Almeyda
Modeling the Reverberation Response of the Dusty Torus Emission from AGN
10/1/2014
Kristina Punzi
An Unbiased Radio Emission Line Survey of the Protoplanetary Disk Orbiting LkCa 15
10/29/2014
Michael Barbosu & Anthony Hennig
RIT Space Exploration (SPEX) Group and the Cubesat proposal
11/5/2014
Richard O'Shaughnessy
Understanding the precession and inspiral of binary black holes
11/21/2014
Laura Parker
Galaxy Evolution in the Group Environment 
12/3/2014
Sukanya Chakrabarti
Clustered Cepheid variables in Norma:  a distant dwarf galaxy in the plane of the Milky Way
12/172014
TBA
TBA
1/28/2015
TBA
TBA
2/4/2015
TBA
TBA
2/18/2015
TBA
TBA
3/4/2015
TBA
TBA
3/18/2015
TBA
TBA
4/1/2015
TBA
TBA
4/15/2015
TBA
TBA
4/29/2015
TBA
TBA
5/6/2015
TBA
TBA
 
Past Talks
2013-2014 Academic Year Astro Lunch Talks