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
نویسندگان
چکیده
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 lower than those derived for translucent and cold dense clouds, but perhaps only significantly for N2H , NH3, and C3H2. CS depletion 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. CO and N2H + abundances derived here are consistent with recently determined values at positions observed in common.
منابع مشابه
ar X iv : a st ro - p h / 01 11 13 6 v 1 7 N ov 2 00 1 1 Active Optics in Modern , Large Optical Telescopes
متن کامل
ar X iv : a st ro - p h / 02 11 45 7 v 1 2 0 N ov 2 00 2 Time variation of fundamental constants : two phenomenological models
Time variation of fundamental constants, a strong signal of new physics, is analyzed comparing extant data with two phenomenological models. Results are discussed.
متن کاملar 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
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...
متن کاملar X iv : a st ro - p h / 02 11 56 8 v 1 2 6 N ov 2 00 2 1 Properties of tangential and radial angles of muons in EAS ∗
Tangential and radial angles of muons in EAS, a useful concept in investigation of the muon production height, can be used also for the investigation of the muon momenta. A parameter ζ, being a combination of tangential and radial angles, is introduced and its possible applications in investigation of muons in showers are presented.
متن کامل