De la conception instrumentale
à l’exploitation des observables
Accueil > Séminaires > Herschel PACS Spectroscopic Signatures

Herschel PACS Spectroscopic Signatures of Evolution in Local Ultraluminous Galaxies

Jacqueline Fischer (Naval Research Laboratory, Washington DC )

Coupling between radiation, gas, and dust is strong in the compact central regions of gas-rich mergers in their ultraluminous infrared galaxy (ULIRG) stage. I discuss the telltale signs of the effects of high ionization parameters, high far- infrared optical depths, and outflows that may be driven by this coupling, as well as the implications of new Herschel far-infrared observations for the evolutionary stage traced by these systems. The massive outflows detected via P-Cygni profile signatures of excited transitions of molecules such as OH and H2O are seen in early PACS observations of both warm and cold ULIRGs and provide evidence of feedback that may be capable of halting the star-formation process.