Hα kinematics of 11 starburst galaxies selected from the sloan digital sky survey

Abstract

We present analysis of Fabry-Perot interferometric observations for a sample of 11 starburst galaxies with redshift z {greater-than or approximate} 0.03 selected from theSloan Digital Sky Survey. We have targeted the Hα λ6562.78 emission line at spatial sampling of 0.2arcsec-0.4 arcsec and at spectral resolution of R~16000. Studying two-dimensional maps for the velocity, velocity dispersion, line emission and continuum deliver new insights into the nature of starburst and postburst galaxies. The velocity fields are fitted to an exponential disc model, providing scalelengths and masses, to be compared with the photometric scalelength and the mass estimated from the velocity dispersions. From the line emission, the star formation rates are also calculated and compared with values in the literature. We have found thatbetween 55 and 64 per cent of our sample show large-scale dominating rotation, while 27 per cent show local rotation typically restricted to the central part of each system. The morphology and line profiles in the centre of eight objects are consistent with a recent merger, while another two seem to be involved in a accretion process which, for the moment, has not disruptedtheir kinematics. © 2013 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.