EXTENDED [C II] EMISSION IN LOCAL LUMINOUS INFRARED GALAXIES

作者：Diaz Santos T^*; Armus L; Charmandaris V; Stacey G; Murphy E J; Haan S; Stierwalt S; Malhotra S; Appleton P; Inami H; Magdis G E; Elbaz D; Evans A S; Mazzarella J M; Surace J A; van der Werf P P; Xu C K; Lu N; Meijerink R; Howell J H; Petric A O; Veilleux S; Sanders D B

来源：Astrophysical Journal Letters, 2014, 788(1): L17.

DOI：10.1088/2041-8205/788/1/L17

• galaxies: ISM
• galaxies: nuclei
• galaxies: starburst
• infrared: galaxies

We present Herschel/PACS observations of extended [C II] 157.7 mu m line emission detected on similar to 1-10 kpc scales in 60 local luminous infrared galaxies ( LIRGs) from the Great Observatories All-sky LIRG Survey. We find that most of the extra-nuclear emission show [C II]/FIR ratios %26gt;= 4 x 10(-3), larger than the mean ratio seen in the nuclei, and similar to those found in the extended disks of normal star-forming galaxies and the diffuse interstellar medium of our Galaxy. The [C II] %26quot;deficits%26quot; found in the most luminous local LIRGs are therefore restricted to their nuclei. There is a trend for LIRGs with warmer nuclei to show larger differences between their nuclear and extra-nuclear [C II]/FIR ratios. We find an anti-correlation between [C II]/FIR and the luminosity surface density, SIR, for the extended emission in the spatially resolved galaxies. However, there is an offset between this trend and that found for the LIRG nuclei. We use this offset to derive a beam filling-factor for the star-forming regions within the LIRG disks of similar to 6% relative to their nuclei. We confront the observed trend to photo-dissociation region models and find that the slope of the correlation is much shallower than the model predictions. Finally, we compare the correlation found between [C II]/FIR and SIR with measurements of high-redshift starbursting IR-luminous galaxies.

• 出版日期2014-6-10
• 单位中国地震局