In Bhr 71 : a Binary Protostellar System ?
نویسنده
چکیده
New Anglo-Australian Telescope near-infrared and Swedish-ESO Submillimetre Telescope CO obJ p 2 r 1 servations are combined with existing Infrared Space Observatory mid-infrared and Australia Telescope Compact Array centimeter radio continuum observations to examine the protostellar content of the Bok globule BHR 71. Together with observations of Herbig-Haro objects, these data show the following: (1) Two protostellar sources, IRS 1 and IRS 2, with a separation of ∼17 (3400 AU) are located within BHR 71. (2) Each protostar is driving its own molecular outflow. The outflow from IRS 1 is much larger in extent, is more massive, and dominates the CO emission. (3) Both protostars are associated with Herbig-Haro objects and shock-excited 2.122 mm H2 v p S(1) emission, which coincide spatially with their CO outflows. (4) IRS 1 is associated with centimeter continuum 1–0 emission, with a flat or rising spectrum, which is consistent with free-free emission, a signpost of protostellar origin. Subject headings: binaries: general — ISM: globules — ISM: individual (BHR 71) — ISM: jets and outflows — stars: formation — stars: pre–main-sequence On-line material: color figures
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