Herschel/HIFI observations of high-J CO lines in the NGC 1333 low-mass star-forming region
Artikel i vetenskaplig tidskrift, 2010
Herschel/HIFI observations of high-J lines (up to J_u = 10) of ^12CO, ^13CO and C^18O are presented toward three deeply embedded low-mass protostars, NGC 1333 IRAS 2A, IRAS 4A, and IRAS 4B, obtained as part of the Water In Star-forming regions with Herschel (WISH) key program. The spectrally-resolved HIFI data are complemented by ground-based observations of lower-J CO and isotopologue lines. The ^12CO 10-9 profiles are dominated by broad (FWHM 25-30 km s^-1) emission. Radiative transfer models are used to constrain the temperature of this shocked gas to 100-200 K. Several CO and ^13CO line profiles also reveal a medium-broad component (FWHM5-10 km s^-1), seen prominently in H_2O lines. Column densities for both components are presented, providing a reference for determining abundances of other molecules in the same gas. The narrow C^18O 9-8 lines probe the warmer part of the quiescent envelope. Their intensities require a jump in the CO abundance at an evaporation temperature around 25 K, thus providing new direct evidence for a CO ice evaporation zone around low-mass protostars.
stars: formation
astrochemistry
ISM: jets and outflows
ISM: molecules
Författare
U. A. Yildiz
Universiteit Leiden
E. F. van Dishoeck
Max-Planck-Gesellschaft
Universiteit Leiden
L. Kristensen
Universiteit Leiden
R. Visser
Universiteit Leiden
J. K. Jorgensen
Köpenhamns universitet
G. J. Herczeg
Max-Planck-Gesellschaft
T. A. van Kempen
Harvard-Smithsonian Center for Astrophysics
Universiteit Leiden
M. R. Hogerheijde
Universiteit Leiden
S. Doty
Denison University
A. O. Benz
Eidgenössische Technische Hochschule Zürich (ETH)
S. Bruderer
Eidgenössische Technische Hochschule Zürich (ETH)
S. F. Wampfler
Eidgenössische Technische Hochschule Zürich (ETH)
E. Deul
Universiteit Leiden
R. Bachiller
Observatorio Astronómico Nacional (OAN)
A. Baudry
Laboratoire d'Astrophysique de Bordeaux
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
J. Braine
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
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)
F. Herpin
Laboratoire d'Astrophysique de Bordeaux
T. Jacq
Laboratoire d'Astrophysique de Bordeaux
D. Johnstone
National Research Council Canada
University of Victoria
B. Larsson
Stockholms universitet
D. Lis
California Institute of Technology (Caltech)
René Liseau
Chalmers, Institutionen för radio- och rymdvetenskap, Radioastronomi och astrofysik
F.-C. Liu
Max-Planck-Gesellschaft
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, 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-García
Institut de Radioastronomie Millimétrique (IRAM)
P. Saraceno
Universita degli Studi di Roma Tor Vergata
R. Shipman
Netherlands Institute for Space Research (SRON)
M. Tafalla
Observatorio Astronómico Nacional (OAN)
Aggm Tielens
Universiteit Leiden
F. F. S. van der Tak
Netherlands Institute for Space Research (SRON)
Rijksuniversiteit Groningen
F. Wyrowski
Max-Planck-Gesellschaft
P. Dieleman
Netherlands Institute for Space Research (SRON)
W. Jellema
Netherlands Institute for Space Research (SRON)
V. Ossenkopf
Universität zu Köln
R. Schieder
Universität zu Köln
J. Stutzki
Universität zu Köln
Astronomy and Astrophysics
0004-6361 (ISSN) 1432-0746 (eISSN)
Vol. 521 1 L40+- L40Ämneskategorier
Astronomi, astrofysik och kosmologi
Fundament
Grundläggande vetenskaper
DOI
10.1051/0004-6361/201015119