Published October 3, 2013
| public
Journal Article
Ortho/Para Ratio of H_2O^+ Toward Sagittarius B2(M) Revisited
Abstract
The HIFI instrument aboard the Herschel satellite has allowed the observation and characterization of light hydrides, the building blocks of interstellar chemistry. In this article, we revisit the ortho/para ratio for H_2O^+ toward the Sgr B2(M) cloud core. The line of sight toward this star forming region passes through several spiral arms and the gas in the Bar potential in the inner Galaxy. In contrast to earlier findings, which used fewer lines to constrain the ratio, we find a ratio of 3, which is uniformly consistent with high-temperature formation of the species. In view of the reactivity of this ion, this matches the expectations.
Additional Information
© 2013 American Chemical Society. Received: December 18, 2012; Revised: May 27, 2013; Published: May 28, 2013. HIFI has been designed and built by a consortium of institutes and university departments from across Europe, Canada, and the United States under the leadership of SRON Netherlands Institute for Space Research, Groningen, The Netherlands, and with major contributions from Germany, France, and the US Consortium members are as follows: Canada, CSA, U. Waterloo; France, CESR, LAB, LERMA, IRAM; Germany, KOSMA, MPIfR, MPS; Ireland, NUI Maynooth; Italy, ASI, IFSI-INAF, Osservatorio Astrofisico di Arcetri-INAF; Netherlands, SRON, TUD; Poland, CAMK, CBK; Spain, Observatorio Astronomico Nacional (IGN), Centro de Astrobiologica (CSIC-INTA); Sweden, Chalmers University of Technology−MC2, RSS & GARD, Onsala Space Observatory, Swedish National Space Board, Stockholm University−Stockholm Observatory; Switzerland, ETH Zurich, FHNW; USA, Caltech, JPL, NHSC. Support for this work was provided by NASA through an award issued by JPL/Caltech. We appreciate funding for the ASTRONET Project CATS (05A09EUA) and the ALMA ARC (5A11PK3) through the Bundesministerium für Bildung und Forschung (BMBF) and through SFB 956 from the DFG. We thank our referees for helpful comments, which improved the discussion of the paper.Additional details
- Eprint ID
- 42854
- DOI
- 10.1021/jp312364c
- Resolver ID
- CaltechAUTHORS:20131205-094505076
- NASA/JPL/Caltech
- 05A09EUA
- ASTRONET Project CATS
- 5A11PK3
- Bundesministerium für Bildung und Forschung (BMBF)
- SFB 956
- Deutsche Forschungsgemeinschaft (DFG)
- Created
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2013-12-05Created from EPrint's datestamp field
- Updated
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2021-11-10Created from EPrint's last_modified field