HERSCHEL-HIFI spectroscopy of the intermediate mass protostar NGC7129 FIRS 2

D. Johnstone , M. Fich , C. Mccoey , T. A. van Kempen , A. Fuente (1) , L. E. Kristensen , J. Cernicharo (2) , P. Caselli (3) , R. Visser , R. Plume , G. J. Herczeg , E. F. van Dishoeck , S. Wampfler , R. Bachiller (1) , Alain Baudry (4, 5, 6, 7) , M. Benedettini (1) , E. Bergin , A. O. Benz , P. Bjerkeli , G. Blake (8) , Sylvain Bontemps (4, 5, 6, 7) , J. Braine (4, 5, 6, 7) , S. Bruderer , C. Codella (1) , F. Daniel , A. M. Di Giorgio , C. Dominik (9) , S. D. Doty , P. Encrenaz (10) , T. Giannini , J. R. Goicoechea (10) , Th. de Graauw , F. Helmich (1) , Fabrice Herpin (4, 5, 6, 7) , M. R. Hogerheijde , T. Jacq (4, 5, 6, 7) , J. K. Jørgensen , B. Larsson (1) , D. Lis (1) , R. Liseau , M. Marseille (4, 5, 6, 7, 11) , G. Melnick (1) , D. Neufeld (1) , B. Nisini (12) , M. Olberg (13) , B. Parise (14) , Justin Pearson (1) , C. Risacher (15) , J. Santiago-García , P. Saraceno (16) , R. Shipman , M. Tafalla , F. van Der Tak (1) , F. Wyrowski (17) , U. A. Yildiz , E. Caux (14) , N. Honingh , W. Jellema , R. Schieder , D. Teyssier (18) , N. Whyborn

1 LAOG - Laboratoire d'Astrophysique de Grenoble
2 CSIC - Centro de Investigaciones Biológicas
3 OAA - INAF - Osservatorio Astrofisico di Arcetri
4 LAB - Laboratoire d'Astrophysique de Bordeaux [Pessac]
5 OASU - Observatoire aquitain des sciences de l'univers
6 UB - Université Sciences et Technologies - Bordeaux 1
7 L3AB - Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux
8 LOCIE - LabOratoire proCédés énergIe bâtimEnt
9 AI PANNEKOEK - Astronomical Institute Anton Pannekoek
10 LERMA - Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique
11 SRON - SRON Netherlands Institute for Space Research
12 OAR - INAF - Osservatorio Astronomico di Roma
13 Onsala Space Observatory
14 CESR - Centre d'étude spatiale des rayonnements
15 ESO
16 IFSI - Istituto di Fisica dello Spazio Interplanetario
17 MPIFR - Max-Planck-Institut für Radioastronomie
18 Herschel Science Center [Madrid]

HERSCHEL-HIFI observations of water from the intermediate mass protostar NGC7129 FIRS 2 provide a powerful diagnostic of the physical conditions in this star formation environment. Six spectral settings, covering four H216O and two H218O lines, were observed and all but one H218O line were detected. The four H2 16 O lines discussed here share a similar morphology: a narrower, \approx 6 km/s, component centered slightly redward of the systemic velocity of NGC7129 FIRS 2 and a much broader, \approx 25 km/s component centered blueward and likely associated with powerful outflows. The narrower components are consistent with emission from water arising in the envelope around the intermediate mass protostar, and the abundance of H2O is constrained to \approx 10-7 for the outer envelope. Additionally, the presence of a narrow self-absorption component for the lowest energy lines is likely due to self-absorption from colder water in the outer envelope. The broader component, where the H2O/CO relative abundance is found to be \approx 0.2, appears to be tracing the same energetic region that produces strong CO emission at high J.

Domaines: Astrophysique stellaire et solaire [astro-ph.SR]; Astrophysique stellaire et solaire [astro-ph.SR]

D. Johnstone, M. Fich, C. Mccoey, T. A. van Kempen, A. Fuente, et al.. HERSCHEL-HIFI spectroscopy of the intermediate mass protostar NGC7129 FIRS 2. Astronomy and Astrophysics - A&A, 2010, 521, pp.L41. ⟨10.1051/0004-6361/201015122⟩. ⟨hal-00521335⟩