Resonant stripping as the origin of dwarf spheroidal galaxies (2009)
D'Onghia, Elena, Besla, Gurtina, Cox, Thomas J., Hernquist, Lars
Dwarf spheroidal galaxies are the most dark matter dominated systems in the nearby Universe and their origin is one of the outstanding puzzles of how galaxies form. Dwarf spheroidals are poor in gas...
Revisiting the Role of M31 in the Dynamical History of the Magellanic Clouds (2009)
Kallivayalil, Nitya, Besla, Gurtina, Sanderson, Robyn, Alcock, Charles
We study the dynamics of the Magellanic Clouds in a model for the Local Group whose mass is constrained using the timing argument/two-body limit of the action principle. The goal is to evaluate the...
New Analysis of the Proper Motions of the Magellanic Clouds using HST/WFPC2 (2008)
Kallivayalil, Nitya, Van Der Marel, Roeland P., Anderson, Jay, Besla, Gurtina, Alcock, Charles
In HST Cycles 11 and 13 we obtained two epochs of ACS/HRC data for fields in the Magellanic Clouds centered on background quasars. We used these data to determine the proper motions of the LMC and...
The Binarity of the Magellanic Clouds and the Formation of the Magellanic Stream (2008)
Besla, Gurtina, Kallivayalil, Nitya, Hernquist, Lars, Van Der Marel, Roeland P., Cox, T. J., Robertson, Brant, ...
The HST proper motion (PM) measurements of the Clouds have severe implications for their interaction history with the Milky Way (MW) and with each other. The Clouds are likely on their first passage...
Kinematical Structure of the Magellanic System (2008)
Van Der Marel, Roeland P., Kallivayalil, Nitya, Besla, Gurtina
We review our understanding of the kinematics of the LMC and the SMC, and their orbit around the Milky Way. The line-of-sight velocity fields of both the LMC and SMC have been mapped with high...
Hopkins, Philip F., Hernquist, Lars, Cox, Thomas J., Younger, Joshua D., Besla, Gurtina
Previous models of galactic disk heating in interactions invoke restrictive assumptions not necessarily valid in modern LCDM contexts: that satellites and orbits are rigid and circular, with slow...
On the Origin of Dynamically Cold Rings Around the Milky Way (2008)
Younger, Joshua D., Besla, Gurtina, Cox, T. J., Hernquist, Lars, Robertson, Brant, Willman, Beth
We present a scenario for the production of dynamically cold rings around the Milky Way via a high-eccentricity, flyby encounter. These initial conditions are more cosmologically motivated than those...
Publications of the Astronomical Society of the Pacific, 115:479--483, 2003 April (2007)
The Astronomical Society, John R. Percy, Gurtina Besla, Vince Velocci, Gregory W. Henry
We report multiperiodicity in five small-amplitude pulsating red giants: RZ Ari, V523 Mon, BC CMi, UX Lyn, and FS Com. For each of these stars, two or three periods recur in each season of our 5000...
Are the Magellanic Clouds on their First Passage about the Milky Way? (2007)
Besla, Gurtina, Kallivayalil, Nitya, Hernquist, Lars, Robertson, Brant, Cox, T. J., Van Der Marel, Roeland P., ...
Recent proper motion measurements of the Large and Small Magellanic Clouds (LMC and SMC, respectively) by Kallivayalil et al (2006a,b) suggest that the 3D velocities of the Clouds are substantially...
Formation of Narrow Dust Rings in Circumstellar Debris Disks (2006)
Narrow dust rings observed around some young stars (e.g., HR 4796A) need to be confined. We present a possible explanation for the formation and confinement of such rings in optically thin...