Two types of distribution of the gas velocity dispersion of MaNGA
  galaxies
  The distribution of the gas velocity dispersion sigma across the images of
1146 MaNGA galaxies is analyzed. We find that there are two types of
distribution of the gas velocity dispersion across the images of galaxies: (i)
the distributions of 909 galaxies show a radial symmetry with or without the
sigma enhancement at the center (R distribution) and (ii) distributions with a
band of enhanced sigma along the minor axis in the images of 159 galaxies with
or without the sigma enhancement at the center (B distribution) The sigma
distribution across the images of 78 galaxies cannot be reliable classified. We
select 806 galaxies with the best defined characteristics (this sample includes
687 galaxies with R distribution and 119 galaxies with B distribution) and
compare the properties of galaxies with R and B distributions. We find that the
median value of the gas velocity dispersion sigma_m in galaxies with B
distribution is higher by around 5 km/s, on average, than that of galaxies with
R distribution. The optical radius R_25 of galaxies with B distribution is
lower by around 0.1 dex, on average, than that of galaxies with similar masses
with R distribution. Thus the properties of a galaxy are related to the type of
distribution of the gas velocity dispersion across its image. This suggests
that the presence of the band of the enhanced gas velocity dispersion can be an
indicator of a specific evolution (or a specific stage in the evolution) of a
galaxy.
