Counting Pairs of Faint Galaxies
Session 107 -- Galaxies: Morphology and Interactions
Display presentation, Thursday, 12, 1995, 9:20am - 6:30pm

[107.12] Counting Pairs of Faint Galaxies

D.Woods, G.G.Fahlman, H.B.Richer (UBC)

The number of pairs of galaxies observed to faint magnitude limits, when compared to nearby samples, determines the interaction or merger rate as a function of redshift. The prevalence of mergers at intermediate redshifts is fundamental to understanding how galaxies evolve and the relative population of galaxy types. In a recent HST study of faint radio galaxy fields (Burkey et al. 1994), a pair membership of $34\pm9$ $\%$ was observed for galaxies with I=18.5-23. Using CFHT deep ($I\leq24$) imaging of a `blank' field we find a significantly lower pair fraction using the same criteria and approach as Burkey et al. This suggests that interactions of faint galaxies may not be as important a factor as originally thought. The colors and morphologies of our close pairs are discussed and we attempt to measure the pair fraction as a function of magnitude.