Previous | Session 138 | Next | Author Index | Block Schedule
D.R. Schwenk, S.A. Lamb (UIUC), J.A. Van Schelt, N.C. Hearn (U.Chicago)
We present an analysis of the nearby interacting galaxies NGC 6621/22 (Arp 81), comparing the results of a combined N-body/SPH simulation of the collision between two suitable disk galaxy models with multi-wavelength observations. Arp 81 is undergoing a strong collision that has triggered periods of intense star formation in the pair. We use archived IRAC and HST images to identify regions of extensive star formation that took place in the system at previous times. From the simulation we obtain information on the physical conditions that likely existed in these regions, and that drove the star formation. By scaling the models, using best estimates of the mass and radius of each galaxy, we find the timescale for various star formation events. We deduce that there has been mass transfer from the more massive NGC 6621 to the less massive NGC 6622, and that this has led to nuclear star formation in NGC 6622. There has also been extensive star formation in two extended ‘arms’ in NGC 6621, one of which formed a bridge between the two galaxies. (This work was supported in part by the National Science Foundation, under grant PHY-0243675, and by the Department of Energy under contract DOE LLNL B506657. The numerical simulations were performed on the Turing Computer Cluster in the College of Engineering at UIUC.)
The author(s) of this abstract have provided an email address for comments about the abstract: slamb@uiuc.edu
Previous | Session 138 | Next
Bulletin of the American Astronomical Society, 37 #4
© 2005. The American Astronomical Soceity.