Galaxy And Mass Assembly (GAMA): the signatures of galaxy interactions
  as viewed from small scale galaxy clustering
  Statistical studies of galaxy-galaxy interactions often utilise net change in
physical properties of progenitors as a function of the separation between
their nuclei to trace both the strength and the observable timescale of their
interaction. In this study, we use two-point auto, cross and mark correlation
functions to investigate the extent to which small-scale clustering properties
of star forming galaxies can be used to gain physical insight into
galaxy-galaxy interactions between galaxies of similar optical brightness and
stellar mass. The Halpha star formers, drawn from the highly spatially complete
Galaxy And Mass Assembly (GAMA) survey, show an increase in clustering on small
separations. Moreover, the clustering strength shows a strong dependence on
optical brightness and stellar mass, where (1) the clustering amplitude of
optically brighter galaxies at a given separation is larger than that of
optically fainter systems, (2) the small scale clustering properties (e.g. the
strength, the scale at which the signal relative to the fiducial power law
plateaus) of star forming galaxies appear to differ as a function of increasing
optical brightness of galaxies. According to cross and mark correlation
analyses, the former result is largely driven by the increased dust content in
optically bright star forming galaxies. The latter could be interpreted as
evidence of a correlation between interaction-scale and optical brightness of
galaxies, where physical evidence of interactions between optically bright star
formers, likely hosted within relatively massive halos, persist over larger
separations than those between optically faint star formers.
