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arXiv · 0709.3430

The irradiated ISM of ULIRGs

M. Spaans·R. Meijerink·F. P. Israel·A. F. Loenen·W. A. Baan
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Abstract

The nuclei of ULIRGs harbor massive young stars, an accreting central black hole, or both. Results are presented for molecular gas that is exposed to X-rays (1-100 keV, XDRs) and far-ultraviolet radiation (6-13.6 eV, PDRs). Attention is paid to species like HCO+, HCN, HNC, OH, H2O and CO. Line ratios of HCN/HCO+ and HNC/HCN discriminate between PDRs and XDRs. Very high J (>10) CO lines, observable with HIFI/Herschel, discriminate very well between XDRs and PDRs. In XDRs, it is easy to produce large abundances of warm (T>100 K) H2O and OH. In PDRs, only OH is produced similarly well.

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M. Spaans, R. Meijerink, F. P. Israel, A. F. Loenen, W. A. Baan. 2007-09-21. The irradiated ISM of ULIRGs. https://doi.org/10.1017/s1743921307013580

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