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. ===== The Detection of Chloronium, H2Cl+, in the Interstellar Medium ===== Chloronium has been detected in absorption with the //Herschel// satellite toward the star-forming regions NGC 6334I and Sagittarius B2(S):\\ D. C. Lis, J. C. Pearson, D. A. Neufeld, et al.\\ **[[https://doi.org/10.1051/0004-6361/201014959|//Herschel///HIFI Discovery of Interstellar Chloronium (H<sub>2</sub>Cl<sup>+</sup>)]]**\\ //Astron. Astrophys.// **521**, (2010) Art. No. L9.\\ Three transitions have been detected toward NGC 6334I which show broadening by Cl hyperfine splitting and no recognizable absorption caused by spiral arm clouds. The 2<sub>12</sub> –1<sub>01</sub> transition of //ortho//-H<sub>2</sub>Cl<sup>+</sup> has been observed near 781.6 and 780.05 GHz for the <sup>35</sup>Cl and <sup>37</sup>Cl isotopologs, respectively. The 1<sub>11</sub> –0<sub>00</sub> transition of //para//-H<sub>2</sub><sup>35</sup>Cl<sup>+</sup> was observed near 485.4 GHz.\\ The absorption features near 485.4 and 780.05 GHz were both affected by emission features from dimethyl ether. A preliminary model for this molecule permitted accounting for these emmsion features in the analyses. This is a clear example that features by so-called "weed" species can affect "flowers" even in the case of //Herschel// observations. The recent report on the rotational spectroscopy of dimethyl ether by C. P. Endres et al., //Astron. Astrophys.// **504**, (2009) 635, were instrumental.\\ The 1<sub>11</sub> –0<sub>00</sub> transition of //para//-H<sub>2</sub><sup>35</sup>Cl<sup>+</sup>, observed toward Sgr B2(S), displays absorption features of spiral arm clouds. More recently, H<sub>2</sub>Cl<sup>+</sup> has turned out to be rather widespread. The 1<sub>11</sub> –0<sub>00</sub> transition of the //para// species was observed with the //Herschel// satellite for both <sup>35</sup>Cl and <sup>37</sup>Cl isotopologs in absorption toward the strong contiunuum sources W31C and Sgr A (+50 km/s cloud). The transition was seen in emission in Orion S and in the photon-dominated region Orion Bar by:\\ D. A. Neufeld, E. Roueff, R. L. Snell, et al.\\ **[[https://doi.org/10.1088/0004-637X/748/1/37|//Herschel// Observations of Interstellar Chloronium]]**\\ //Astrophys. J.// **748**, (2012) Art. No. 37. ---- Contributor(s): H. S. P. Müller; 10, 2010; 3, 2012 ---- molecules/ism/h2cl-plus.txt Last modified: 2019/10/21 17:40by mueller