Probable detection of H_2D+ in the starless core Barnard 68
- Autor(en)
- M. R. Hogerheijde, P. Caselli, M. Emprechtinger, F. F. S. van der Tak, J. Alves, A. Belloche, R. Güsten, A. A. Lundgren, L.-Å. Nyman, N. Volgenau, M. C. Wiedner
- Abstrakt
Context: The presence of H2D+ in dense cloud cores underlies ion-molecule reactions that strongly enhance the deuterium fractionation of many molecular species. Aims: We determine the H2D+abundance in one starless core, Barnard 68, that has a particularly well established physical, chemical, and dynamical structure. Methods: We observed the ortho-H2D+ ground-state line110-111, the N2H+ J=4-3 line, and theH13CO+ 4-3 line with the APEX telescope. Results:We report the probable detection of the o-H2D+ line at an intesity T_mb=0.22± 0.08 K and exclusively thermal line width,and find only upper limits to the N2H+ 4-3 andH13CO+ 4-3 intensities. Conclusions: Within the uncertainties in the chemical reaction rates and the collisional excitation rates, chemical model calculations and excitation simulations reproduce the observed intensities and that of o-H2D+ in particular.
- Organisation(en)
- Institut für Astrophysik
- Externe Organisation(en)
- European Southern Observatory (Germany), Leiden University, INAF - Osservatorio Astrofisico di Arcetri, Universität zu Köln, SRON Netherlands Institute for Space Research , Max-Planck-Institut für Radioastronomie
- Journal
- Astronomy & Astrophysics
- Band
- 454
- Seiten
- L59-L62
- ISSN
- 0004-6361
- DOI
- https://doi.org/10.1051/0004-6361:20065104
- Publikationsdatum
- 08-2006
- Peer-reviewed
- Ja
- ÖFOS 2012
- 103003 Astronomie
- Schlagwörter
- Link zum Portal
- https://ucrisportal.univie.ac.at/de/publications/637600d5-5ec5-4955-bf98-d41dd33beafb