{"paper":{"title":"Strong CH+ J=1-0 emission and absorption in DR21","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.GA","authors_text":"A. Fuente, A. Harris, A. Marston, A. O.~Benz, B. Godard, Ch. Joblin, C. Kramer, C. Risacher, D. Neufeld, D. Teyssier, E. Falgarone, F. Boulanger, F. Schm\\\"ulling, F. van der Tak, H. Yorke, J. Martin-Pintado, J. Pearson, J. Stutzki, M. Fich, M. Gerin, M. R\\\"ollig, M. Salez, N. Erickson, P. Lesaffre, P. Martin, R. G\\\"usten, R. Simon, S. Cabrit, S. Lord, T. G.~Phillips, T. Klein, V. Ossenkopf, W. Jellema","submitted_at":"2010-07-08T17:10:07Z","abstract_excerpt":"We report the first detection of the ground-state rotational transition of the methylidyne cation CH+ towards the massive star-forming region DR21 with the HIFI instrument onboard the Herschel satellite. The line profile exhibits a broad emission line, in addition to two deep and broad absorption features associated with the DR21 molecular ridge and foreground gas. These observations allow us to determine a CH+ J=1-0 line frequency of 835137 +/- 3 MHz, in good agreement with a recent experimental determination. We estimate the CH+ column density to be a few 1e13 cm^-2 in the gas seen in emissi"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1007.1420","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"}