A large sample of Kohonen selected E+A (post-starburst) galaxies from
  the Sloan Digital Sky Survey
  We aim to create a large sample of local post-starburst (PSB) galaxies to
study their characteristic properties, particularly morphological features
indicative of gravitational distortions and indications for active galactic
nuclei (AGNs). The selection is based on a huge Kohonen self-organising map
(SOM) of about one million SDSS spectra. The SOM is made fully available for
the astronomical community, in combination with an interactive user interface.
We compiled a catalogue of 2665 PSB galaxies with redshifts z < 0.4. In the
colour-mass diagram, the PSB sample is found to be clearly concentrated towards
the region between the red and the blue cloud, in agreement with the idea that
PSB galaxies represent the transitioning phase between actively and passively
evolving galaxies. The relative frequency of morphologically distorted PSB
galaxies is at least 57%, significantly higher than in a comparison sample. The
search for AGNs based on conventional selection criteria in the radio and MIR
results in a low AGN fraction of 2 - 3%. We confirm an MIR excess in the mean
SED of the PSB galaxy sample that may indicate hidden AGNs, though other
sources are also possible. (Abstract modified to match the arXiv format.)
