Bibcode
Richer, M. G.; Georgiev, L.; Rosado, M.; Bullejos, A.; Valdez-Gutiérrez, M.; Dultzin-Hacyan, D.
Referencia bibliográfica
Astronomy and Astrophysics, v.397, p.99-107 (2003)
Fecha de publicación:
1
2003
Revista
Número de citas
14
Número de citas referidas
13
Descripción
We present Fabry-Perot and multi-object spectroscopy of the galaxies in
Hickson compact group 31 (HCG 31). Based upon our Hα data cubes,
galaxies A and C are a single entity, showing no discontinuity in their
kinematics. Kinematically, galaxy E is probably a component of the A+C
complex; otherwise it is a recently detached fragment. Galaxy F appears,
both kinematically and chemically, to have formed from material tidally
removed from the A+C complex. Galaxies B and G are kinematically
distinct from this complex. Galaxy Q also has a radial velocity
compatible with group membership. Galaxies A, B, C, and F have nearly
identical oxygen abundances, despite spanning a luminosity range of 5
mag. Galaxy B's oxygen abundance is normal for its luminosity, while
galaxy F's abundance is that expected given its origin as a tidal
fragment of the A+C complex. The oxygen abundances in galaxies A and C
are also understandable if the A+C complex is a late-type spiral
suffering strong gas inflow and star formation as a result of a tidal
interaction. Given the kinematics of both the galaxies and the H I gas,
the oxygen abundances, and the position of galaxy G, we propose that an
interaction of galaxy G with the A+C complex, rather than a merger of
galaxies A and C, is a more complete explanation for the tidal features
and other properties of HCG 31. In this case, the A+C complex need not
be a merger in progress, though this is not ruled out.