Detalles de publicación

PP 017023

The JCMT Nearby Galaxies Legacy Survey -- XI. -- Environmental Variations in the Atomic and Molecular Gas Radial Profiles of Nearby Spiral Galaxies

Angus Mok, C. D. Wilson, J. H. Knapen, J. R. Sanchez-Gallego, E. Brinks, E. Rosolowsky
Various
We present an analysis of the radial profiles of a sample of 43 HI-flux selected spiral galaxies from the Nearby Galaxies Legacy Survey (NGLS) with resolved James Clerk Maxwell Telescope (JCMT) CO J=3−2 and/or Very Large Array (VLA) HI maps. Comparing the Virgo and non-Virgo populations, we confirm that the HI disks are truncated in the Virgo sample, even for these relatively HI-rich galaxies. On the other hand, the H2 distribution is enhanced for Virgo galaxies near their centres, resulting in higher H2 to HI ratios and steeper H2 and total gas radial profiles. This is likely due to the effects of moderate ram pressure stripping in the cluster environment, which would preferentially remove low density gas in the outskirts while enhancing higher density gas near the centre. Combined with Hα star formation rate data, we find that the star formation efficiency (SFR/H2) is relatively constant with radius for both samples, but Virgo galaxies have a ∼40% lower star formation efficiency than non-Virgo galaxies.

 
Aceptado para publicación en MNRAS | Enviado el 2017-02-14 | Proyecto P/300724