Herschel observations of deuterated water towards Sgr B2(M)
2010 (English)In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 521, L38- p.Article in journal (Refereed) Published
Observations of HDO are an important complement for studies of water, because they give strong constraints on the formation processes - grain surfaces versus energetic process in the gas phase, e. g. in shocks. The HIFI observations of multiple transitions of HDO in Sgr B2(M) presented here allow the determination of the HDO abundance throughout the envelope, which has not been possible before with ground-based observations only. The abundance structure has been modeled with the spherical Monte Carlo radiative transfer code RATRAN, which also takes radiative pumping by continuum emission from dust into account. The modeling reveals that the abundance of HDO rises steeply with temperature from a low abundance (2.5 x 10(-11)) in the outer envelope at temperatures below 100 K through a medium abundance (1.5 x 10(-9)) in the inner envelope/outer core at temperatures between 100 and 200 K, and finally a high abundance (3.5 x 10(-9)) at temperatures above 200 K in the hot core.
Place, publisher, year, edition, pages
2010. Vol. 521, L38- p.
ISM: molecules, molecular processes, line: formation
Astronomy, Astrophysics and Cosmology
IdentifiersURN: urn:nbn:se:su:diva-51352DOI: 10.1051/0004-6361/201015121ISI: 000284150900038OAI: oai:DiVA.org:su-51352DiVA: diva2:384917
authorCount :562011-01-102011-01-102011-01-10Bibliographically approved