Deuterated Ammonia in Galactic Protostellar Cores

Autor:	H. Alwyn Wootten, Ronak Y. Shah
Jazyk:	angličtina
Rok vydání:	2001
Předmět:	Physics Ammonia chemistry.chemical_compound Deuterium chemistry Space and Planetary Science Star formation Astrophysics (astro-ph) FOS: Physical sciences Astronomy and Astrophysics Astrophysics Galaxy
Popis:	We report on a survey of \nh2d towards protostellar cores in low-mass star formation and quiescent regions in the Galaxy. Twenty-three out of thirty-two observed sources have significant ($\gsim 5\sigma$) \nh2d emission. Ion-molecule chemistry, which preferentially enhances deuterium in molecules above its cosmological value of \scnot{1.6}{-5} sufficiently explains these abundances. NH2D/NH3 ratios towards Class 0 sources yields information about the ``fossil remnants'' from the era prior to the onset of core collapse and star formation. We compare our observations with predictions of gas-phase chemical networks. Comment: 16 Pages, 7 Figures, Accepted to Ap.J., to appear in the June 20, 2001 edition
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::ad2024059dc8ee1459b195690c926d08 http://arxiv.org/abs/astro-ph/0103264 Zobrazit plný text záznamu