| Description |
We will perform a comprehensive far-infrared spectroscopic and photometric survey of infrared bright galaxies at local andintermediate redshifts. Our goal is to use the superior sensitivity, spatial and spectral resolution of Herschel to study these galaxies with minimal extinction effects. We aim to obtain a comprehensive view of the physical processes at work in the interstellar medium of local galaxies ranging from objects with moderately enhanced star formation to the most dense, energetic, and obscured environments in ultra-luminous infrared galaxies (ULIRGs) and around AGN. The objects cover a wide parameter range in luminosity, activity level, and metal enrichment, and will be complemented by a few objects at intermediate redshifts, i.e. at a more active epoch of star formation. In particular we plan to- study the obscuration and physical conditions of the central regions of infrared galaxies by obtaining full PACS and SPIRE spectra of five template starbursts, AGN and ULIRGs. - characterise for a larger local sample the state of the ionised medium and of photo-dissociation and X-ray dominated regions through PACS observations of key diagnostic fine-structure and molecular lines. The densest and warmest region near AGN will also be probed for highly excited CO emission,- determine the role of metallicity in star formation processes of low metallicity galaxies from the nearby LMC/SMC to more distant galaxies, - search for evolution from the intermediate redshift population close to the peak of cosmic star formation till the present time, - study the triggering mechanisms and temporal evolution of infrared activity by photometric mapping of a large sample of interacting galaxies,- determine the structure of a few local templates by spectroscopic mapping along characteristic axes. These PACS line maps will establish the physical conditions of nuclear region, spiral arms/disk, and wind regions. |
