Water in massive star-forming regions: HIFI observations of W3 IRS5
Artikel i vetenskaplig tidskrift, 2010

We present Herschel observations of the water molecule in the massive star-forming region W3 IRS5. The o-H\_2^17O 1_10-1_01, p-H\_2^18O 1_11-0_00, p-H_2O 2_02-1_11, p-H_2O 1_11-0_00, o-H_2O 2_21-2_12, and o-H_2O 2_12-1_01 lines, covering a frequency range from 552 up to 1669 GHz, have been detected at high spectral resolution with HIFI. The water lines in W3 IRS5 show well-defined high-velocity wings that indicate a clear contribution by outflows. Moreover, the systematically blue-shifted absorption in the H_2O lines suggests expansion, presumably driven by the outflow. No infall signatures are detected. The p-H_2O 1_11-0_00 and o-H_2O 2_12-1_01 lines show absorption from the cold material (T ~ 10 K) in which the high-mass protostellar envelope is embedded. One-dimensional radiative transfer models are used to estimate water abundances and to further study the kinematics of the region. We show that the emission in the rare isotopologues comes directly from the inner parts of the envelope (T \gsim 100 K) where water ices in the dust mantles evaporate and the gas-phase abundance increases. The resulting jump in the water abundance (with a constant inner abundance of 10^-4) is needed to reproduce the o-H\_2^17O 1_10-1_01 and p-H\_2^18O 1_11-0_00 spectra in our models. We estimate water abundances of 10^-8 to 10^-9 in the outer parts of the envelope (T \lsim 100 K). The possibility of two protostellar objects contributing to the emission is discussed. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.

Författare

L. Chavarría

Institut National des Sciences de l'Univers

Laboratoire d'Astrophysique de Bordeaux

F. Herpin

Laboratoire d'Astrophysique de Bordeaux

Institut National des Sciences de l'Univers

T. Jacq

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

S. Bontemps

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

M. Marseille

Netherlands Institute for Space Research (SRON)

F. F. S. van der Tak

Rijksuniversiteit Groningen

Netherlands Institute for Space Research (SRON)

B. Pietropaoli

Institut National des Sciences de l'Univers

Ecole des Mines de Nantes

Laboratoire d'Astrophysique de Bordeaux

F. Wyrowski

Max-Planck-Gesellschaft

R. Shipman

Netherlands Institute for Space Research (SRON)

W. Frieswijk

Netherlands Institute for Space Research (SRON)

E. F. van Dishoeck

Universiteit Leiden

Max-Planck-Gesellschaft

J. Cernicharo

Centro de Astrobiologia (CAB)

R. Bachiller

Observatorio Astronómico Nacional (OAN)

M. Benedettini

Istituto di Fisica dello Spazio Interplanetario, Rome

A. O. Benz

Eidgenössische Technische Hochschule Zürich (ETH)

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. Bruderer

Eidgenössische Technische Hochschule Zürich (ETH)

P. Caselli

University of Leeds

Osservatorio Astrofisico di Arcetri

C. Codella

Osservatorio Astrofisico di Arcetri

F. Daniel

Centro de Astrobiologia (CAB)

A. M. di Giorgio

Istituto di Fisica dello Spazio Interplanetario, Rome

C. Dominik

Anton Pannekoek Institute for Astronomy

Radboud Universiteit

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

Osservatorio Astronomico di Roma

J. R. Goicoechea

Centro de Astrobiologia (CAB)

T. de Graauw

Netherlands Institute for Space Research (SRON)

P. Hartogh

MPI für Sonnensystemforschung

F. Helmich

Netherlands Institute for Space Research (SRON)

G. J. Herczeg

Max-Planck-Gesellschaft

M. R. Hogerheijde

Universiteit Leiden

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

C. McCoey

Western University

University of Waterloo

G. J. Melnick

Harvard-Smithsonian Center for Astrophysics

B. Nisini

Osservatorio Astronomico di Roma

Michael Olberg

Chalmers, Institutionen för radio- och rymdvetenskap, Nationella anläggningen för radioastronomi

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

Istituto di Fisica dello Spazio Interplanetario, Rome

J. Stutzki

Universität zu Köln

R. Szczerba

Polish Academy of Sciences

M. Tafalla

Observatorio Astronómico Nacional (OAN)

A. Tielens

Universiteit Leiden

T. A. van Kempen

Harvard-Smithsonian Center for Astrophysics

R. Visser

Universiteit Leiden

S. F. Wampfler

Eidgenössische Technische Hochschule Zürich (ETH)

J. Willem

Netherlands Institute for Space Research (SRON)

U. A. Yildiz

Universiteit Leiden

Astronomy and Astrophysics

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

Vol. 521 1 L37+- L37

Ämneskategorier

Astronomi, astrofysik och kosmologi

Fundament

Grundläggande vetenskaper

DOI

10.1051/0004-6361/201015113

Mer information

Senast uppdaterat

2020-06-02