Interaction rate at z ~ 1
Vladimir P. Reshetnikov
Received 8 June 1999 / Accepted 30 October 1999
We found 25 galaxies with probable tidal tails in the Hubble Deep Fields North and South at z=0.5-1.5. General characteristics of the selected tidal features are very close to characteristics of tidal tails of local interacting galaxies. Using objects with z=0.5-1.0, we found that volume density of galaxies with tidal tails changes with z as . Therefore, we estimated the rate of close encounters between the galaxies of comparable mass leading to the formation of extended tidal structures. If this rate reflects the merger rate, our data support a steeply increasing merger rate at 1 and consistent with zero curvature universe.
Key words: galaxies: interactions galaxies: photometry galaxies: peculiar galaxies: structure
© European Southern Observatory (ESO) 2000
Online publication: December 8, 1999