Bok Globules in the Lmc

نویسندگان

  • D. R. Garnett
  • J. R. Walsh
  • Y. - H. Chu
  • B. M. Lasker
چکیده

We report the discovery of small, isolated dust clouds in the Large Magellanic Cloud, which are excellent candidates for counterparts to the Bok globules observed in the Galaxy. We detect these small clouds silhouetted against diffuse Hα emission, based on parallel imaging with the WFPC-2 on HST. The clouds we identify as Bok globule candidates have typical sizes of approximately 1 ′′ , corresponding to about 0.25 pc linear diameter at the distance of the LMC. We derive lower limits to the optical depth within the dark clouds, and masses assuming that the clouds have density distributions similar to Galactic Bok globules. The sizes and estimated masses for LMC globules are comparable to those estimated for Galactic globules. An extended sample of such objects would be excellent targets for high-resolution infrared and millimeter observations to study low-mass star formation in such clouds in low-metallicity environments, where the distance is well known.

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تاریخ انتشار 1999