Herschel-SPIRE observations of Arp 220: An Unprecedented View of the Molecular Gas in an Extreme Star Formation Environment

Details Herschel-SPIRE observations of Arp 220: An Unprecedented View of the Molecular Gas in an Extreme Star Formation Environment Herschel-SPIRE observations of Arp 220: An Unprecedented View of the Molecular Gas in an Extreme Star Formation Environment

Jan 2012

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2012aas...21942713r&link_type=abstract

American Astronomical Society, AAS Meeting #219, #427.13

Astronomy and Astrophysics

Astronomy

Scientific paper

We present Herschel SPIRE-FTS observations of Arp 220, a nearby ULIRG. The FTS continuously covers 190 -- 670 microns, providing a good measurement of the continuum and detection of several molecular and atomic species. We detect luminous CO (J = 4-3 to 13-12) and water ladders with comparable total luminosity; very high-J HCN absorption; OH+, H2O+, and HF in absorption; and CI and NII. Modeling of the continuum yields warm dust, with T = 66 K, and an unusually large optical depth of 5 at 100 microns. Non-LTE modeling of the CO shows two temperature components: cold molecular gas at T 50 K and warm molecular gas at T 1350 K. The mass of the warm gas is 10% of the cold gas, but dominates the luminosity of the CO ladder. The temperature of the warm gas is in excellent agreement with H2 rotational lines. At 1350 K, H2 dominates the cooling ( 20 Lsun/Msun) in the ISM compared to CO ( 0.4 Lsun/Msun). We found that only a non-ionizing source such as the mechanical energy from supernovae and stellar winds can excite the warm gas and satisfy the energy budget of 20 Lsun/Msun. We detect a massive molecular outflow in Arp 220 from the analysis of strong P-Cygni line profiles observed in OH+, H2O+, and H2O. The outflow has a mass > 107 Msun and is bound to the nuclei with velocity < 250 km/s. The large column densities observed for these molecular ions strongly favor the existence of an X-ray luminous AGN (1044 ergs/s) in Arp 220.

Affiliated with

Also associated with

No associations

Rating

Herschel-SPIRE observations of Arp 220: An Unprecedented View of the Molecular Gas in an Extreme Star Formation Environment does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Herschel-SPIRE observations of Arp 220: An Unprecedented View of the Molecular Gas in an Extreme Star Formation Environment, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Herschel-SPIRE observations of Arp 220: An Unprecedented View of the Molecular Gas in an Extreme Star Formation Environment will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1583890