Hydrides in young stellar objects: Radiation tracers in a protostar-disk-outflow system
Journal article, 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.

Author

A. O. Benz

Swiss Federal Institute of Technology in Zürich (ETH)

S. Bruderer

Swiss Federal Institute of Technology in Zürich (ETH)

E. F. van Dishoeck

Max Planck Institute

Leiden University

P. Stäuber

Swiss Federal Institute of Technology in Zürich (ETH)

S. F. Wampfler

Swiss Federal Institute of Technology in Zürich (ETH)

M. Melchior

University of Applied Sciences Northwestern Switzerland, School of Enginnering

Swiss Federal Institute of Technology in Zürich (ETH)

C. Dedes

Swiss Federal Institute of Technology in Zürich (ETH)

F. Wyrowski

Max Planck Institute

S. Doty

Denison University

F. F. S. van der Tak

University of Groningen

Netherlands Institute for Space Research (SRON)

W. Bächtold

Swiss Federal Institute of Technology in Zürich (ETH)

A. Csillaghy

University of Applied Sciences Northwestern Switzerland, School of Enginnering

A. Megej

Swiss Federal Institute of Technology in Zürich (ETH)

C. Monstein

Swiss Federal Institute of Technology in Zürich (ETH)

M. Soldati

University of Applied Sciences Northwestern Switzerland, School of Enginnering

R. Bachiller

Spanish National Observatory (OAN)

A. Baudry

Institut National des Sciences de l'Univers

Laboratoire d'Astrophysique de Bordeaux

M. Benedettini

University of Rome Tor Vergata

E. A. Bergin

University of Michigan

Per Bjerkeli

Chalmers, Department of Radio and Space Science, Radio Astronomy and Astrophysics

G. A. Blake

California Institute of Technology (Caltech)

S. Bontemps

Institut National des Sciences de l'Univers

Laboratoire d'Astrophysique de Bordeaux

J. Braine

Laboratoire d'Astrophysique de Bordeaux

Institut National des Sciences de l'Univers

P. Caselli

University of Leeds

Arcetri Astrophysical Observatory

J. Cernicharo

Centro de Astrobiologia (CAB)

C. Codella

Arcetri Astrophysical Observatory

F. Daniel

Centro de Astrobiologia (CAB)

A. M. di Giorgio

University of Rome Tor Vergata

P. Dieleman

Netherlands Institute for Space Research (SRON)

C. Dominik

Anton Pannekoek Institute for Astronomy

Radboud University

P. Encrenaz

LERMA - Laboratoire d'Etudes du Rayonnement et de la Matiere en Astrophysique et Atmospheres

M. Fich

University of Waterloo

A. Fuente

Spanish National Observatory (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 Institute

F. Herpin

Institut National des Sciences de l'Univers

Laboratoire d'Astrophysique de Bordeaux

M. R. Hogerheijde

Leiden University

T. Jacq

Arcetri Astrophysical Observatory

W. Jellema

Netherlands Institute for Space Research (SRON)

D. Johnstone

National Research Council Canada

University of Victoria

J. K. Jorgensen

University of Copenhagen

L. Kristensen

Leiden University

B. Larsson

Stockholm University

D. Lis

California Institute of Technology (Caltech)

René Liseau

Chalmers, Department of Radio and Space Science, Radio Astronomy and Astrophysics

M. Marseille

Netherlands Institute for Space Research (SRON)

C. McCoey

Western University

University of Waterloo

G. J. Melnick

Harvard-Smithsonian Center for Astrophysics

D. A. Neufeld

Johns Hopkins University

B. Nisini

Osservatorio Astronomico di Roma

Michael Olberg

Chalmers, Department of Radio and Space Science, National Facility for Radio Astronomy

V. Ossenkopf

University of Cologne

B. Parise

Max Planck Institute

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

Instituto de Radioastronomía Milimétrica

P. Saraceno

University of Rome Tor Vergata

R. Schieder

University of Cologne

R. Shipman

Netherlands Institute for Space Research (SRON)

J. Stutzki

University of Cologne

M. Tafalla

Spanish National Observatory (OAN)

Aggm Tielens

Leiden University

T. A. van Kempen

Harvard-Smithsonian Center for Astrophysics

R. Visser

Leiden University

U. A. Yildiz

Leiden University

Astronomy and Astrophysics

0004-6361 (ISSN) 1432-0746 (eISSN)

Vol. 521 1 L35+- L35

Subject Categories

Astronomy, Astrophysics and Cosmology

Roots

Basic sciences

DOI

10.1051/0004-6361/201015111

More information

Latest update

5/23/2019