Ccd imaging of ngc 4861 : morphology and brightness distribution

Abstract

We discuss narrow band CCD imaging of NGC 4861 in continua at 4500 Å, 5300 Å and 6300 Å as well as in Hα, Hβ and [OIII] λ 5007Å lines. We find that the system exhibits a double nucleus structure anda counter-tail to the well-known NE chain of HII regions. The mean value of lines and continua frames for the main body brightness distribution ofNGC 4861 is R-2.04±0.35, comparable to the Hubble-Reynolds law R-². The three mentioned characteristics indicate that NGC 4861 might have undergone a merger process. The time elapsed from the beginning of the phenomenon is set to be smaller than three crossing times. New observations are proposed to confirm or reject the merger scenario for this peculiar galaxy.