Show pageOld revisionsBacklinksBack to top This page is read only. You can view the source, but not change it. Ask your administrator if you think this is wrong. ===== Reports on the Detection of Oxydanium, H3O+, in the ISM ===== Two groups reported almost simultaneously the detection of the //J<sub>K</sub><sup>v<sub>t</sub></sup>// = 1<sub>1</sub><sup>–</sup> – 2<sub>1</sub><sup>+</sup> at 307192.41 MHz:\\ J. M. Hollis, E. B. Churchwell, E. Herbst, and F. C. de Lucia,\\ **[[https://doi.org/10.1038/322524a0|An Interstellar Line Coincident with the P(2,1) Transition of Hydronium (H<sub>3</sub>O<sup>+</sup>)]]**\\ //Nature// **322**, 524–626 (1986);\\ with the NRAO 12 m telescope towards Orion KL; and\\ A. Wootten, F. Boulanger, M. Bogey, F. Combes, P. J. Encrenaz, M. Gerin, and L. Ziurys,\\ **[[https://ui.adsabs.harvard.edu/abs/1986A%26A...166L..15W|A Search for Interstellar H<sub>3</sub>O<sup>+</sup>]]**\\ //Astron. Astrophys.// **166**, L15–L18 (1986); with the NRAO 12 m telescope towards OMC-1 (essentially identical to Orion KL) and Sgr B2(OH).\\ **Note:** see below for the Orion KL case ! Later, additional transitions have been reported, e.g. the 3<sub>2</sub><sup>+</sup> – 2<sub>2</sub><sup>–</sup> transition at 364797.427 MHz:\\ A. Wootten, J. G. Mangum, B. E. Turner, M. Bogey, F. Boulanger, F. Combes, P. J. Encrenaz, and M. Gerin,\\ **[[https://doi.org/10.1086/186178|Detection of Interstellar H<sub>3</sub>O<sup>+</sup> – A Confirming Line]]**\\ //Astrophys. J.// **380**, L79–L83 (1991),\\ towards OMC-1, Sgr B2(OH) and (N). The 3<sub>0</sub><sup>+</sup> – 2<sub>0</sub><sup>–</sup> transition at 396272.412 MHz along with the previously mentioned transitions have been detected in several hot core sources:\\ T. G. Phlips, E. F. van Dishoek, J. Keene,\\ **[[https://doi.org/10.1086/171945|Interstellar H<sub>3</sub>O<sup>+</sup> and its Relation to the O<sub>2</sub> and H<sub>2</sub>O Abundances]]**\\ //Astrophys. J.// **399**, 533–550 (1992).\\ The sources, in which the cation reportedly was detected newly, are W3 IRS5 (aka W3 M), W3(OH), W51 M, and G34.3 +0.15. A line detected at 4.3121 (5) THz with KOA was tentativel assigned to the 4<sub>3</sub><sup>–</sup> – 3<sub>3</sub><sup>+</sup> transition:\\ R. Timmermann, T. Nikola, A. Poglitsch, N. Geis, G. J. Stacey, and C. H. Townes,\\ **[[https://doi.org/10.1086/310055|Possible Discovery of the 70 Micron H<sub>3</sub>O<sup>+</sup> 4<sub>3</sub><sup>–</sup> – 3<sub>3</sub><sup>+</sup> Transition in Orion BN–IRc2]]**\\ //Astrophys. J.// **463**, L109–L112 (1996);\\ three additional transitions were reported, one of which was overlapped with a line of H<sub>2</sub><sup>18</sup>O:\\ J. R. Goicoechea and J. Cernicharo,\\ **[[https://doi.org/10.1086/321712|Far-Infrared Detection of H<sub>3</sub>O<sup>+</sup> in Sagittarius B2]]**,\\ //Astrophys. J.// **554**, L213–L216 (2001). Recent //Herschel///HIFI observations failed to detect any H<sub>3</sub>O<sup>+</sup> in Orion KL near 984.7, 1655.8, and 1657.25 GHz. Thus, previous reports on observations of this molecular ion in Orion KL could no be confirmed. It is possible that emission lines observed at lower frequencies (near 307.2, 364.8, and 396.3 GHz; see above) are caused by other species:\\ H. Gupta, P. Rimmer, J. C. Pearson, et al.,\\ **[[https://doi.org/10.1051/0004-6361/201015117|Detection of OH<sup>+</sup> and H<sub>2</sub>O<sup>+</sup> towards Orion KL]]**\\ //Astron. Astrophys.// **521**, (2010) Art. No. L47. ---- Contributor(s): H. S. P. Müller; 01, 2008; 05, 2011 ---- molecules/ism/h3o-plus.txt Last modified: 2019/10/22 17:07by mueller