Hydrides in young stellar objects: Radiation tracers in a protostar-disk-outflow system
Artikel i vetenskaplig tidskrift, 2010
Context. Hydrides of the most abundant heavier elements are fundamental molecules in cosmic chemistry. Some of them trace gas irradiated by UV or X-rays.
Aims: We explore the abundances of major hydrides in W3 IRS5, a prototypical region of high-mass star formation.
Methods: W3 IRS5 was observed by HIFI on the Herschel Space Observatory with deep integration (\sime2500 s) in 8 spectral regions.
Results: The target lines including CH, NH, H_3O^+, and the new molecules SH^+, H_2O^+, and OH^+ are detected. The H_2O^+ and OH^+ J = 1-0 lines are found mostly in absorption, but also appear to exhibit weak emission (P-Cyg-like). Emission requires high density, thus originates most likely near the protostar. This is corroborated by the absence of line shifts relative to the young stellar object (YSO). In addition, H_2O^+ and OH^+ also contain strong absorption components at a velocity shifted relative to W3 IRS5, which are attributed to foreground clouds.
Conclusions: The molecular column densities derived from observations correlate well with the predictions of a model that assumes the main emission region is in outflow walls, heated and irradiated by protostellar UV radiation. Herschel is an ESA space observatory with science instruments provided by a European-led Principal Investigator consortia and with important participation from NASA.
Författare
A. O. Benz
Eidgenössische Technische Hochschule Zürich (ETH)
S. Bruderer
Eidgenössische Technische Hochschule Zürich (ETH)
E. F. van Dishoeck
Universiteit Leiden
Max-Planck-Gesellschaft
P. Stäuber
Eidgenössische Technische Hochschule Zürich (ETH)
S. F. Wampfler
Eidgenössische Technische Hochschule Zürich (ETH)
M. Melchior
University of Applied Sciences Northwestern Switzerland, School of Enginnering
Eidgenössische Technische Hochschule Zürich (ETH)
C. Dedes
Eidgenössische Technische Hochschule Zürich (ETH)
F. Wyrowski
Max-Planck-Gesellschaft
S. Doty
Denison University
F. F. S. van der Tak
Rijksuniversiteit Groningen
Netherlands Institute for Space Research (SRON)
W. Bächtold
Eidgenössische Technische Hochschule Zürich (ETH)
A. Csillaghy
University of Applied Sciences Northwestern Switzerland, School of Enginnering
A. Megej
Eidgenössische Technische Hochschule Zürich (ETH)
C. Monstein
Eidgenössische Technische Hochschule Zürich (ETH)
M. Soldati
University of Applied Sciences Northwestern Switzerland, School of Enginnering
R. Bachiller
Observatorio Astronómico Nacional (OAN)
A. Baudry
Laboratoire d'Astrophysique de Bordeaux
Institut National des Sciences de l'Univers
M. Benedettini
Universita degli Studi di Roma Tor Vergata
E. A. Bergin
University of Michigan
Per Bjerkeli
Chalmers, Institutionen för radio- och rymdvetenskap, Radioastronomi och astrofysik
G. A. Blake
California Institute of Technology (Caltech)
S. Bontemps
Laboratoire d'Astrophysique de Bordeaux
Institut National des Sciences de l'Univers
J. Braine
Institut National des Sciences de l'Univers
Laboratoire d'Astrophysique de Bordeaux
P. Caselli
University of Leeds
Osservatorio Astrofisico di Arcetri
J. Cernicharo
Centro de Astrobiologia (CAB)
C. Codella
Osservatorio Astrofisico di Arcetri
F. Daniel
Centro de Astrobiologia (CAB)
A. M. di Giorgio
Universita degli Studi di Roma Tor Vergata
P. Dieleman
Netherlands Institute for Space Research (SRON)
C. Dominik
Anton Pannekoek Institute for Astronomy
Radboud Universiteit
P. Encrenaz
LERMA - Laboratoire d'Etudes du Rayonnement et de la Matiere en Astrophysique et Atmospheres
M. Fich
University of Waterloo
A. Fuente
Observatorio Astronómico Nacional (OAN)
T. Giannini
Osservatorio Astronomico di Roma
J. R. Goicoechea
Centro de Astrobiologia (CAB)
T. de Graauw
Netherlands Institute for Space Research (SRON)
F. Helmich
Netherlands Institute for Space Research (SRON)
G. J. Herczeg
Max-Planck-Gesellschaft
F. Herpin
Laboratoire d'Astrophysique de Bordeaux
Institut National des Sciences de l'Univers
M. R. Hogerheijde
Universiteit Leiden
T. Jacq
Osservatorio Astrofisico di Arcetri
W. Jellema
Netherlands Institute for Space Research (SRON)
D. Johnstone
University of Victoria
National Research Council Canada
J. K. Jorgensen
Köpenhamns universitet
L. Kristensen
Universiteit Leiden
B. Larsson
Stockholms universitet
D. Lis
California Institute of Technology (Caltech)
René Liseau
Chalmers, Institutionen för radio- och rymdvetenskap, Radioastronomi och astrofysik
M. Marseille
Netherlands Institute for Space Research (SRON)
C. McCoey
University of Waterloo
Western University
G. J. Melnick
Harvard-Smithsonian Center for Astrophysics
D. A. Neufeld
Johns Hopkins University
B. Nisini
Osservatorio Astronomico di Roma
Michael Olberg
Chalmers, Institutionen för radio- och rymdvetenskap, Nationella anläggningen för radioastronomi
V. Ossenkopf
Universität zu Köln
B. Parise
Max-Planck-Gesellschaft
J. C. Pearson
Jet Propulsion Laboratory, California Institute of Technology
R. Plume
University of Calgary
C. Risacher
Netherlands Institute for Space Research (SRON)
J. Santiago-García
Institut de Radioastronomie Millimétrique (IRAM)
P. Saraceno
Universita degli Studi di Roma Tor Vergata
R. Schieder
Universität zu Köln
R. Shipman
Netherlands Institute for Space Research (SRON)
J. Stutzki
Universität zu Köln
M. Tafalla
Observatorio Astronómico Nacional (OAN)
Aggm Tielens
Universiteit Leiden
T. A. van Kempen
Harvard-Smithsonian Center for Astrophysics
R. Visser
Universiteit Leiden
U. A. Yildiz
Universiteit Leiden
Astronomy and Astrophysics
0004-6361 (ISSN) 1432-0746 (eISSN)
Vol. 521 1 L35+- L35Ämneskategorier
Astronomi, astrofysik och kosmologi
Fundament
Grundläggande vetenskaper
DOI
10.1051/0004-6361/201015111