Detalles de publicación

PP 013059

The James Clerk Maxwell Telescope Nearby Galaxies Legacy Survey IX: 12CO J=3-2 Observations of NGC 2976 and NGC 3351

Boon-Kok Tan et al. (incl. J. H. Knapen, J. R. Sanchez-Gallego)
Oxford, IAC, otros
We present 12CO J=3-2 maps of NGC 2976 and NGC 3351 obtained with the James Clerk Maxwell Telescope (JCMT), both early targets of the JCMT Nearby Galaxy Legacy Survey (NGLS). We combine the present observations with 12CO J=1-0 data and find that the computed 12CO J=3-2 to 12CO J=1-0 line ratio (R31) agrees with values measured in other NGLS field galaxies. We compute the MH2 value and find that it is robust against the value of R31 used. Using Hi data from the The Hi Nearby Galaxy Survey (THINGS) survey, we find a tight correlation between surface density of H2 and star formation rate density for NGC 3351 when 12CO J=3→2 data are used. Finally, we compare the 12CO J=3-2 intensity with the PAH 8 micron surface brightness and find a good correlation in the high surface brightness regions. We extend this study to include all 25 Spitzer Infrared Nearby Galaxies Survey (SINGS) galaxies within the NGLS sample and find a tight correlation at large spatial scales. We suggest that both PAH 8 micron and 12CO J=3-2 are likely to originate in regions of active star formation.

 
Aceptado para publicación en MNRAS | Enviado el 2013-09-05 | Proyecto 3I2407