2000/05/08 by N. Bergvall, Nils Bergvall, J. Masegosa +8
Engineering · Physics and Astronomy · #Adaptive optics and wavefront sensing #Advanced Measurement and Metrology Techniques #Astrophysics (astro-ph) #Calibration and Measurement Techniques #FOS: Physical sciences #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/0005178
11 pages. Accepted for publication in Astronomy and Astrophysics
arxiv created 2000/05/08 · openalex publication_date 2000/05/08 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We present far infrared (FIR) spectroscopy of the luminous blue compact galaxy (BCG) Haro 11 (ESO 350-IG38) obtained with the ISO Long Wavelength Spectrometer (LWS) in low resolution mode. This metal poor dwarf merger is an extremely hot IRAS source with a high [CII]158um/CO(1-0) flux ratio. We discuss the balance between dust and line cooling in the photodissociated regions (PDR), in particular the role of the [CII] line, and derive the basic properties of the PDR gas. While samples of other starburst galaxies show a correlation between the [CII]/FIR flux ratio and the IRAS f60/f100 ratio, Haro 11 deviates significantly from this relationship being brighter in [CII] than average. We propose that the relationship is caused by an increasing optical depth with increasing IRAS temperature but that the low metallicity and the extreme starburst properties of Haro 11 allow the medium to be thin despite its high f60/f100 ratio, explaining the [CII] excess. This leaves room for a more optimistic view on the possibilities to detect massive starforming mergers at high redshifts, using the [CII] line.