ar X iv : a st ro - p h / 02 08 29 8 v 1 1 5 A ug 2 00 2 Abundances of Molecular Species in Barnard 68
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چکیده
Abundances for 5 molecules (CO, CS, NH3, H2CO, and C3H2) and 1 molecular ion (N2H ) and upper limits for the abundances of 1 molecule (CO) and 1 molecular ion (HCO) are derived for gas within the Bok globule Barnard 68 (B68). The abundances were determined using our own BIMA millimeter interferometer data and single-dish data gathered from the literature, in conjunction with a Monte Carlo radiative transfer model. Since B68 is the only starless core to have its density structure strongly constrained via extinction mapping, a major uncertainty has been removed from these determinations. All abundances for B68 are lower than those derived for translucent and cold dense clouds, but perhaps only significantly for N2H , NH3, and C3H2. Depletion of CS toward the extinction peak of B68 is hinted at by the large offset between the extinction peak and the position of maximum CS line brightness. Abundances derived here for CO and N2H + are consistent with other, recently determined values at positions observed in common. Subject headings: ISM: molecules — ISM: abundances — ISM: globules — ISM: individual (B68) — stars: formation
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ar X iv : a st ro - p h / 02 08 29 8 v 2 1 6 A ug 2 00 2 Abundances of Molecular Species in Barnard 68
Abundances for 5 molecules (CO, CS, NH3, H2CO, and C3H2) and 1 molecular ion (N2H ) and upper limits for the abundances of 1 molecule (CO) and 1 molecular ion (HCO) are derived for gas within the Bok globule Barnard 68 (B68). The abundances were determined using our own BIMA millimeter interferometer data and single-dish data gathered from the literature, in conjunction with a Monte Carlo radia...
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ar X iv : a st ro - p h / 02 11 58 1 v 1 2 6 N ov 2 00 2 1 MOLECULAR ABUNDANCES IN BARNARD 68
Abundances for CO, CS, NH3, H2CO, C3H2, and N2H + and upper limits for the abundances of CO and HCO are derived for gas within the Bok globule B68 using our own BIMA array data, single-dish data from the literature, and Monte Carlo radiative transfer models. B68 has had its density structure well determined, removing a major uncertainty from abundance determinations. All abundances for B68 are ...
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