CN column densities and excitation temperatures

Abstract

We analyse abundances and rotational temperatures of the interstellar CN molecule. We have calculated the column densities and excitation temperatures of the molecule along 73 lines of sight basing on our original measurements of the B 2Σ+ - X2Σ+ (0,0) vibrational band recorded in high signal-to-noise ratio spectra and also for 88 directions based on measurements already available in literature. We compare the column densities obtained from different bands of CN molecule available to ground-based instruments. The obtained excitation temperatures in the analysed directions show always an excess over the cosmic microwave background radiation (CMBR) temperature. © 2008 The Authors.