{"paper":{"title":"Herschel observations in the ultracompact HII region Mon R2: Water in dense Photon-dominated regions (PDRs)","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.GA","authors_text":"A. Fuente, A. Harris, A. Lorenzani, A.O. Benz, A. Usero, B. Mookerjea, C. Dedes, C. Joblin, C. Kramer, C. McCoey, D.A. Neufeld, D. Teyssier, F. Boulanger, F. Le Petit, F. van der Tak, H. Yorke, J. Cernicharo, J. Martin-Pintado, J. Pearson, J. Pety, J.R. Goicoechea, J.R. Rizzo, J. Stutzki, K. France, K. Schuster, M. Akyilmaz, M. Fich, M. Gerin, M.Gonzalez-Garcia, M. Melchior, M. Rollig, O.Berne, P. Dieleman, P.G. Martin, P. Pilleri, R. Gusten, R. Simon, R. Szczerba, S. Bruderer, S.D. Lord, S. Garcia-Burillo, T.G. Phillips, T. Klein, V. Ossenkopf, Y. Okada","submitted_at":"2010-07-09T07:55:12Z","abstract_excerpt":"Mon R2, at a distance of 830 pc, is the only ultracompact HII region (UC HII) where the photon-dominated region (PDR) between the ionized gas and the molecular cloud can be resolved with Herschel. HIFI observations of the abundant compounds 13CO, C18O, o-H2-18O, HCO+, CS, CH, and NH have been used to derive the physical and chemical conditions in the PDR, in particular the water abundance. The 13CO, C18O, o-H2-18O, HCO+ and CS observations are well described assuming that the emission is coming from a dense (n=5E6 cm-3, N(H2)>1E22 cm-2) layer of molecular gas around the UC HII. Based on our o-"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1007.1523","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}