Variations in H2O+/H2O ratios toward massive star-forming regions
Artikel i vetenskaplig tidskrift, 2010
Early results from the Herschel Space Observatory revealed the water cation H2O+ to be an abundant ingredient of the interstellar medium. Here we present new observations of the H2O and H2O+ lines at 1113.3 and 1115.2 GHz using the Herschel Space Observatory toward a sample of high-mass star-forming regions to observationally study the relation between H2O and H2O+. Nine out of ten sources show absorption from H2O+ in a range of environments: the molecular clumps surrounding the forming and newly formed massive stars, bright high-velocity outflows associated with the massive protostars, and unrelated low-density clouds along the line of sight. Column densities per velocity component of H2O+ are found in the range of 10^12 to a few 10^13 cm^-2. The highest N(H2O+) column densities are found in the outflows of the sources. The ratios of H2O+/H2O are determined in a range from 0.01 to a few and are found to differ strongly between the observed environments with much lower ratios in the massive (proto)cluster envelopes (0.01-0.1) than in outflows and diffuse clouds. Remarkably, even for source components detected in H2O in emission, H2O+ is still seen in absorption. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.
ISM: molecules
ISM: clouds
submillimeter: ISM
stars: formation
Författare
F. Wyrowski
Max-Planck-Gesellschaft
F. F. S. van der Tak
Rijksuniversiteit Groningen
Netherlands Institute for Space Research (SRON)
F. Herpin
Laboratoire d'Astrophysique de Bordeaux
Institut National des Sciences de l'Univers
A. Baudry
Laboratoire d'Astrophysique de Bordeaux
Institut National des Sciences de l'Univers
S. Bontemps
Laboratoire d'Astrophysique de Bordeaux
Institut National des Sciences de l'Univers
L. Chavarría
Laboratoire d'Astrophysique de Bordeaux
Institut National des Sciences de l'Univers
W. Frieswijk
Rijksuniversiteit Groningen
T. Jacq
Laboratoire d'Astrophysique de Bordeaux
Institut National des Sciences de l'Univers
M. Marseille
Netherlands Institute for Space Research (SRON)
R. Shipman
Netherlands Institute for Space Research (SRON)
E. F. van Dishoeck
Max-Planck-Gesellschaft
Universiteit Leiden
A. O. Benz
Eidgenössische Technische Hochschule Zürich (ETH)
P. Caselli
University of Leeds
M. R. Hogerheijde
Universiteit Leiden
D. Johnstone
University of Victoria
National Research Council Canada
René Liseau
Chalmers, Institutionen för radio- och rymdvetenskap, Radioastronomi och astrofysik
R. Bachiller
Observatorio Astronómico Nacional (OAN)
M. Benedettini
University of Michigan
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)
J. Braine
Institut National des Sciences de l'Univers
Laboratoire d'Astrophysique de Bordeaux
S. Bruderer
Eidgenössische Technische Hochschule Zürich (ETH)
J. Cernicharo
Centro de Astrobiologia (CAB)
C. Codella
Universita degli Studi di Roma Tor Vergata
F. Daniel
Agencia Estatal Consejo Superior de Investigaciones Científicas (CSIC)
LERMA - Laboratoire d'Etudes du Rayonnement et de la Matiere en Astrophysique et Atmospheres
A. M. di Giorgio
Universita degli Studi di Roma Tor Vergata
C. Dominik
Anton Pannekoek Institute for Astronomy
S. Doty
Denison University
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
Universita degli Studi di Roma Tor Vergata
J. R. Goicoechea
Centro de Astrobiologia (CAB)
T. de Graauw
Atacama Large Millimeter-submillimeter Array (ALMA)
F. Helmich
Netherlands Institute for Space Research (SRON)
G. J. Herczeg
Max-Planck-Gesellschaft
J. K. Jorgensen
Köpenhamns universitet
L. Kristensen
Universiteit Leiden
B. Larsson
Stockholms universitet
D. Lis
California Institute of Technology (Caltech)
C. McCoey
University of Waterloo
G. J. Melnick
Harvard-Smithsonian Center for Astrophysics
B. Nisini
Universita degli Studi di Roma Tor Vergata
Michael Olberg
Chalmers, Institutionen för radio- och rymdvetenskap, Radioastronomi och astrofysik
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
Observatorio Astronómico Nacional (OAN)
P. Saraceno
Universita degli Studi di Roma Tor Vergata
M. Tafalla
Observatorio Astronómico Nacional (OAN)
T. A. van Kempen
Harvard-Smithsonian Center for Astrophysics
R. Visser
Universiteit Leiden
S. F. Wampfler
Eidgenössische Technische Hochschule Zürich (ETH)
U. A. Yildiz
Universiteit Leiden
John H Black
Chalmers, Institutionen för radio- och rymdvetenskap, Radioastronomi och astrofysik
E. Falgarone
LERMA - Laboratoire d'Etudes du Rayonnement et de la Matiere en Astrophysique et Atmospheres
M. Gerin
LERMA - Laboratoire d'Etudes du Rayonnement et de la Matiere en Astrophysique et Atmospheres
P. Roelfsema
Netherlands Institute for Space Research (SRON)
P. Dieleman
Netherlands Institute for Space Research (SRON)
D. Beintema
Netherlands Institute for Space Research (SRON)
A. de Jonge
Netherlands Institute for Space Research (SRON)
N. Whyborn
Atacama Large Millimeter-submillimeter Array (ALMA)
J. Stutzki
Universität zu Köln
V. Ossenkopf
Universität zu Köln
Astronomy and Astrophysics
0004-6361 (ISSN) 1432-0746 (eISSN)
Vol. 521 1 L34+- L34Ämneskategorier
Astronomi, astrofysik och kosmologi
Fundament
Grundläggande vetenskaper
DOI
10.1051/0004-6361/201015110