Dynamics of Binary Galaxies

Previous abstract Next abstract

Session 7 -- Clusters of Galaxies/Binary Galaxies
Display presentation, Monday, June 12, 1995, 9:20am - 6:30pm

[7.06] Dynamics of Binary Galaxies

T.E. Nordgren (NAIC, Cornell University), J.N. Chengalur (NFRA), E.E. Salpeter (Cornell University), Y. Terzian (NAIC, Cornell University)

A study has been made of six galaxy pairs which constitute a sample of isolated close binaries in regions of low galaxy density. Observations of these binaries have been conducted using the VLA C array and Palomar 5-meter telescope. HI synthesis maps and line profiles in conjunction with optical images have been used to estimate the orbital characteristics and possible histories of these galaxy pairs. The morphology and velocity differences for individual pairs indicate the galaxies are on high eccentricity, low total energy orbits with a median velocity difference for the sample of only $\sim$ 20 km s$^{-1}$. To investigate the effects of environement on the evolution of close pair interactions this sample is being expanded to include galaxy pairs from regions of medium galaxy density as well as allowing the possibility of a nearby neighbor. This new sample includes 10 pairs, of which 2 were later found to be triplets. Preliminary results show the median velocity difference for these 10 pairs is $\sim$ 100 km s$^{-1}$, significantly higher than for those in lower density regions.

Monday program listing