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| **[[https://doi.org/10.1051/0004-6361:20034490|First Detection of Triply-deuterated Methanol]]**\\ | **[[https://doi.org/10.1051/0004-6361:20034490|First Detection of Triply-deuterated Methanol]]**\\ |
| //Astron. Astrophys.// **416**, 159–163 (2004).\\ | //Astron. Astrophys.// **416**, 159–163 (2004).\\ |
| A dozen lines of CD<sub>3</sub>OH were detected around 158 GHz toward IRAS 16293−2422 with very modest to reasonable signal-to-noise ratios employing the IRAM 30 m telescope. The column density of CH<sub>3</sub>OH was derived from that of <sup>13</sup>CH<sub>3</sub>OH. The CH<sub>3</sub>OH : CH<sub>2</sub>DOH : CHD<sub>2</sub>OH : CD<sub>3</sub>OH ratios were about 126 : 38 : 7.7 : 1.\\ | A dozen lines of CD<sub>3</sub>OH were detected around 158 GHz toward IRAS 16293−2422 with very modest to reasonable signal-to-noise ratios employing the IRAM 30 m telescope. The column density of CH<sub>3</sub>OH was derived from that of <sup>13</sup>CH<sub>3</sub>OH. The CH<sub>3</sub>OH : CH<sub>2</sub>DOH : CHD<sub>2</sub>OH : CD<sub>3</sub>OH ratios were about 126 : 38 : 7.7 : 1.\\ |
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| //Astron. Astrophys.// **677**, Art. No. A49 (2023).\\ | //Astron. Astrophys.// **677**, Art. No. A49 (2023).\\ |
| The authors found some evidence for the presence of this isotopolog in PILS data toward this low-mass protostar. About seven lines are not blended to only partially blended; the signal-to-noise ratio of some lines is only modest. The derived abundance of 0.02 % with respect to the main isotopolog may be reasonable compared to 0.33 % obtained for CD<sub>3</sub>OH described below. Nevertheless, the identification should be viewed as very tentative because of the limited amount of lines and the complexity found in deueration ratios. Identifications of CH<sub>2</sub>DOD and also CHD<sub>2</sub>OD should be more promising.\\ | The authors found some evidence for the presence of this isotopolog in PILS data toward this low-mass protostar. About seven lines are not blended to only partially blended; the signal-to-noise ratio of some lines is only modest. The derived abundance of 0.02 % with respect to the main isotopolog may be reasonable compared to 0.33 % obtained for CD<sub>3</sub>OH described below. Nevertheless, the identification should be viewed as very tentative because of the limited amount of lines and the complexity found in deueration ratios. Identifications of CH<sub>2</sub>DOD and also CHD<sub>2</sub>OD should be more promising.\\ |
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| | H. S. P. Müller, V. V. Ilyushin, A. Belloche, F. Lewen, and S. Schlemmer\\ |
| | reported on an\\ |
| | **[[https://doi.org/10.1051/0004-6361/202451011|Investigation of the Rotational Spectrum of CH<sub>3</sub><sup>17</sup>OH and its Tentative Detection toward Sagittarius B2(N)]]**\\ |
| | //Astron. Astrophys.// **688**, Art. No. A201 (2023).\\ |
| | The authors report a tentative detection of this isotopolog in the ReExploring Molecular Complexity with ALMA survey at 3 mm. Only one unblended and one partially blended line were identified, many more were severely bleded or too weak. The derived CH<sub>3</sub><sup>18</sup>OH to CH<sub>3</sub><sup>17</sup>OH ratio of ~3.3 is along <sup>18</sup>O to <sup>17</sup>O ratios found for other molecules in the Galactic Center as is the CH<sub>3</sub><sup>16</sup>OH to CH<sub>3</sub><sup>18</sup>OH ratio of 240.\\ |
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| **[[https://doi.org/10.1051/0004-6361/202449918|Rotational Spectroscopy of CH<sub>3</sub>OD with a reanalysis of CH<sub>3</sub>OD toward IRAS 16293–2422]]**\\ | **[[https://doi.org/10.1051/0004-6361/202449918|Rotational Spectroscopy of CH<sub>3</sub>OD with a reanalysis of CH<sub>3</sub>OD toward IRAS 16293–2422]]**\\ |
| //Astron. Astrophys.// **687**, Art. No. A220 (2024).\\ | //Astron. Astrophys.// **687**, Art. No. A220 (2024).\\ |
| Unsurprisingly, the authors detected in their PILS data also CH<sub>3</sub>OD in //v//<sub>t</sub> = 1. These lines were instrumental in determing the rotational temperature of ~190 K, which is in accord with ~225 K mentioned in the prvious paragraph, but considerably lower than the estimated ~300 K earlier.\\ | Unsurprisingly, the authors detected in their PILS data also many lines of CH<sub>3</sub>OD in //v//<sub>t</sub> = 1. These lines were instrumental in determing the rotational temperature of ~190 K, which is in accord with ~225 K mentioned in the previous paragraph, but considerably lower than the estimated ~300 K earlier. Adopting earlier values, the amount of CH<sub>3</sub>OD is ~0.32 % that of CH<sub>3</sub>OH, and the CH<sub>2</sub>DOH to CH<sub>3</sub>OD ratio is ~22.5, which translates into a deuteration ratio per H atom of ~7.5.\\ |
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| | H. S. P. Müller, V. V. Ilyushin, A. Belloche, F. Lewen, and S. Schlemmer\\ |
| | reported on an\\ |
| | **[[https://doi.org/10.1051/0004-6361/202451011|Investigation of the Rotational Spectrum of CH<sub>3</sub><sup>17</sup>OH and its Tentative Detection toward Sagittarius B2(N)]]**\\ |
| | //Astron. Astrophys.// **688**, Art. No. A201 (2023).\\ |
| | The authors report a tentative detection of torsionally excited CH<sub>3</sub><sup>18</sup>OH in the ReExploring Molecular Complexity with ALMA survey at 3 mm besides several a clear identification of this isotopolog in its ground torsional state.\\ |
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