Star Formation in the Bok Globule Cb54

نویسندگان

  • David R. Ciardi
  • Cynthia Gómez MartÍn
چکیده

We present mid-infrared (10.4, 11.7, and 18.3 m) imaging intended to locate and characterize the suspected protostellar components within the Bok globule CB54. We detect and confirm the protostellar status for the nearinfrared source CB54YC1-II. The mid-infrared luminosity for CB54YC1-II was found to be Lmidir 8 L , and we estimate a central source mass ofM 0:8M (for a mass accretion rate of Ṁ 1⁄4 10 6 M yr ). CB54 harbors another near-infrared source (CB54YC1-I), which was not detected by our observations. The nondetection is consistent with CB54YC1-I being a highly extinguished embedded young A or B star or a background G or F giant. An alternative explanation for CB54YC1-I is that the source is an embedded protostar viewed at an extremely high inclination angle, and the near-infrared detections are not of the central protostar, but of light scattered by the accretion disk into our line of sight. In addition, we have discovered three newmid-infrared sources, which are spatially coincident with the previously known dense core in CB54. The source temperatures ( 100 K) and association of the mid-infrared sources with the dense core suggests that these mid-infrared objects may be embedded class 0 protostars. Subject headingg s: infrared: ISM — infrared: stars — ISM: globules — ISM: individual (CB54, LBN 1042) — stars: formation — stars: preYmain-sequence

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ar X iv : 0 70 4 . 04 28 v 1 [ as tr o - ph ] 3 A pr 2 00 7 Star Formation in the Bok Globule CB 54

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تاریخ انتشار 2007