Odin water mapping in the Orion KL region
Artikel i vetenskaplig tidskrift, 2003
New results from water mapping observations of the Orion KL region using the submm/mm wave satellite Odin (2.1′ beam size at 557 GHz), are presented. The ortho-H2O JK(+)K(-) = l1.0 → l0.1 ground state transition was observed in a 7′ × 7′ rectangular grid with a spacing of 1′, while the same line of H218O was measured in two positions, Orion KL itself and 2′ south of Orion KL. In the main water species, the KL molecular outflow is largely resolved from the ambient cloud and it is found to have an extension of 60″-110″. The H2O outflow profile exhibits a rather striking absorption-like asymmetry at the line centre. Self-absorption in the near (or "blue") part of the outflow (and possibly in foreground quiescent halo gas) is tentatively suggested to play a role here. We argue that the dominant part of the KL H218O outflow emission emanates from the compact (size ∼15″) low-velocity flow and here estimate an H2O abundance of circa 10-5 compared to all H2 in the flow - an order of magnitude below earlier estimates of the H2O abundance in the shocked gas of the high-velocity flow. The narrow ambient cloud lines show weak velocity trends, both in the N-S and E-W directions. H218O is detected for the first time in the southern position at a level of ∼0.15 K and we here estimate an H2O abundance of (1-8) × 10-8.
ISM: abundances
ISM: individual objects: Orion KL
ISM: molecules
Submillimeter
Författare
Henrik Olofsson
Onsala rymdobservatorium
G. Olofsson
Stockholms observatorium
Åke Hjalmarson
Chalmers, Onsala Rymdobservatorium
Per Bergman
Chalmers, Onsala Rymdobservatorium
John H Black
Chalmers, Onsala Rymdobservatorium
Roy Booth
Chalmers, Onsala Rymdobservatorium
V. Buat
C.L. Curry
University of Waterloo
P. J. Encrenaz
Observatoire de Paris
E. Falgarone
Ecole Normale Superieure (ENS)
P. Feldman
M. Fich
University of Waterloo
H. G. Floren
Stockholms observatorium
U. Frisk
Swedish Space Corporation (SSC)
M. Gerin
Ecole Normale Superieure (ENS)
E.M. Gregersen
McMaster University
J. Harju
Helsingin Yliopisto
T. Hasegawa
University of Calgary
Lars E B Johansson
Chalmers, Onsala Rymdobservatorium
S. Kwok
University of Calgary
B. Larsson
Stockholms observatorium
A. Lecacheux
Observatoire de Paris-Meudon
T Liljeström
René Liseau
Stockholms observatorium
K. Mattila
Helsingin Yliopisto
G.F. Mitchell
Saint Mary's University
H. L. Nordh
Rymdstyrelsen
Michael Olberg
Chalmers, Onsala Rymdobservatorium
H. Olofsson
Stockholms observatorium
L. Pagani
Observatoire de Paris
R. Plume
University of Calgary
I. Ristorcelli
Gustaf Rydbeck
Chalmers, Onsala Rymdobservatorium
Aa. Sandqvist
Stockholms observatorium
F. von Scheele
Swedish Space Corporation (SSC)
G. Serra
N.F. Tothill
Saint Mary's University
K. Volk
University of Calgary
C. D. Wilson
McMaster University
Astronomy and Astrophysics
0004-6361 (ISSN) 1432-0746 (eISSN)
Vol. 402 3 L47-L54Ämneskategorier
Astronomi, astrofysik och kosmologi
Fundament
Grundläggande vetenskaper
Infrastruktur
Onsala rymdobservatorium
DOI
10.1051/0004-6361:20030339