Tidal Dwarf Galaxy candidates in Hickson compact groups of Galaxies

The detailed study of the internal kinematics of tidal dwarf galaxy (TDG) candidates detected in optical and/or HI observations is most important to address the question about their origins. We are conducting a program to measure the kinematics of TDG candidates in compact groups using a Fabry-Perot instrument which allows us to study the 2-D velocity maps of the objects with high spatial and spectral resolutions. Our main goal is to select TDG candidates which have kinematics independent of the possible parent galaxies. In this paper, we describe our results for Stephan's quintet (SQ) and HCG 31. We find that the dynamical masses of the TDG candidates in SQ range from 108 up to 1010 M,D. Two objects to the E and S of HCG 31 A+C present counterrotating patterns with amplitudes of 30 and 40 km s(-1). Region F, which was previously thought to be the best example of TDG presents no rotation.