Herbig Ae/Be Stars in the Magellanic Bridge

Shogo Nishiyama; Yasuaki Haba; Daisuke Kato; Daisuke Baba; Hirofumi Hatano; Motohide Tamura; Yasushi Nakajima; Akika Ishihara; Tetsuya Nagata; Koji Sugitani; Noriyuki Matsunaga; Hinako Fukushi; Nobuhiko Kusakabe; Shuji Sato

doi:10.1086/511326

arXiv · astro-ph/0702504

Herbig Ae/Be Stars in the Magellanic Bridge

Shogo Nishiyama·Yasuaki Haba·Daisuke Kato·Daisuke Baba·Hirofumi Hatano·Motohide Tamura·Yasushi Nakajima·Akika Ishihara·Tetsuya Nagata·Koji Sugitani·Noriyuki Matsunaga·Hinako Fukushi·Nobuhiko Kusakabe·Shuji Sato

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Abstract

We have found Herbig Ae/Be star candidates in the western region of the Magellanic Bridge. Using the near infrared camera SIRIUS and the 1.4 m telescope IRSF, we surveyed about 3.0 deg x 1.3 deg (24 deg < RA < 36 deg, -75 deg < Dec. < -73.7 deg) in the J, H, and Ks bands. On the basis of colors and magnitudes, about 200 Herbig Ae/Be star candidates are selected. Considering the contaminations by miscellaneous sources such as foreground stars and early-type dwarfs in the Magellanic Bridge, we estimate that about 80 (about 40%) of the candidates are likely to be Herbig Ae/Be stars. We also found one concentration of the candidates at the young star cluster NGC 796, strongly suggesting the existence of pre-main-sequence (PMS) stars in the Magellanic Bridge. This is the first detection of PMS star candidates in the Magellanic Bridge, and if they are genuine PMS stars, this could be direct evidence of recent star formation. However, the estimate of the number of Herbig Ae/Be stars depends on the fraction of classical Be stars, and thus a more precise determination of the Be star fraction or observations to differentiate between the Herbig Ae/Be stars and classical Be stars are required.

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Shogo Nishiyama, Yasuaki Haba, Daisuke Kato, Daisuke Baba, Hirofumi Hatano, Motohide Tamura, Yasushi Nakajima, Akika Ishihara, Tetsuya Nagata, Koji Sugitani, Noriyuki Matsunaga, Hinako Fukushi, Nobuhiko Kusakabe, Shuji Sato. 2007-02-20. Herbig Ae/Be Stars in the Magellanic Bridge. https://doi.org/10.1086/511326

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