Herschel/HIFI-HRS observation of CH absorption in IRAS16293-2422

S. Bottinelli (1) , Christophe Caux (2) , Valentine Wakelam (3, 4, 5, 6) , C. Ceccarelli (7) , C. Kahane (7)

1 CESR - Centre d'étude spatiale des rayonnements
2 LIMOS - Laboratoire d'Informatique, de Modélisation et d'optimisation des Systèmes
3 LAB - Laboratoire d'Astrophysique de Bordeaux [Pessac]
4 OASU - Observatoire aquitain des sciences de l'univers
5 UB - Université Sciences et Technologies - Bordeaux 1
6 L3AB - Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux
7 IPAG - Institut de Planétologie et d'Astrophysique de Grenoble

We present high spectral resolution observations of CH absorption towards the low-mass protostar IRAS16293-2422. The data were obtained with the High Resolution Spectrometer (HRS) module of the Heterodyne Instrument for the Far-Infrared (HIFI) on-board Herschel, as part of the CHESS (Chemical HErschel Surveys of Star-forming regions) guaranteed time key program. CH is well known for having column densities correlated with those of H_2 and for its role as a product in the ion-molecule gas-phase chemistry. We derive CH column densities in the envelope of IRAS16293-2422, and investigate the implications when comparing with column densities of H_2 and of other carbon species such as CN or CCH. We also discuss the non-detections of CD and CH^+.

Domaines: Cosmologie et astrophysique extra-galactique [astro-ph.CO]; Cosmologie et astrophysique extra-galactique [astro-ph.CO]

S. Bottinelli, Christophe Caux, Valentine Wakelam, C. Ceccarelli, C. Kahane. Herschel/HIFI-HRS observation of CH absorption in IRAS16293-2422. 2011IAUS.280P.101B - The Molecular Universe, 2011, Tolede, Spain. pp.101P. ⟨hal-00606133⟩