Analysis of emission line widhts of [CII]158μm

Abstract

A study of [CII] 158 μm emission line profiles observed with Herschel PACS for 379 galaxies is presented. Emission line widths are compared to [CII] luminosities, to near-infrared 1.6 μm luminosities and to infrared 22 μm luminosities to decide if any luminosity relates to velocity dispersion. Archival data for [CII] fluxes and line profiles are taken from http://cassis.sirtf.com/ herschel/. Line profiles are classified as Gaussian, flattened and asymmetric. H magnitudes are taken from 2MASS catalogues, and 22 μm fluxes from the WISE catalogue. These luminosities are compared to [CII] line Full Width Half Maximum. Asymmetric profiles are not primarily AGN, which indicates that asymmetries are not produced primarily by outflows from the nuclear region. [CII] line widths do not show a significant correlation with any measure of galaxy luminosity. The correlation having smallest dispersion is with the H band luminosity for which L(H) ~ FWHM0.73, which is a much flatter correlation than the L ~ FWHM4 previously found for optical.