J/ApJ/658/358 Ae/Be stars of Magellanic Bridge in JHKs (Nishiyama+, 2007)
Herbig Ae/Be stars in the Magellanic Bridge.
Nishiyama S., Haba Y., Kato D., Baba D., Hatano H., Tamura M., Nakajima Y.,
Ishihara A., Nagata T., Sugitani K., Matsunaga N., Fukushi H., Kusakabe N.,
Sato S.
<Astrophys. J., 658, 358-366 (2007)>
=2007ApJ...658..358N 2007ApJ...658..358N
ADC_Keywords: Magellanic Clouds ; Stars, pre-main sequence ;
Photometry, infrared
Keywords: infrared: stars - Magellanic Clouds - stars: formation -
stars: pre-main sequence
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
1.4m telescope IRSF, we surveyed ∼3.0°x1.3°
(24°≲RA≲36°, -75.0°≲DE≲-73.7°) 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 (#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.
Description:
Our observations were conducted in 2004 August and 2005 March, July,
and August using the near-infrared camera SIRIUS (Simultaneous
Infrared Imager for Unbiased Survey) on the IRSF (Infrared Survey
Facility) telescope. IRSF is a 1.4m telescope constructed and
operated by Nagoya University and SAAO (South African Astronomical
Observatory) at Sutherland, South Africa.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 60 203 Catalog of Herbig Ae/Be star candidates in the
Magellanic Bridge
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See also:
J/other/PASAu/6.471 : Magellanic Clouds bridge region HI profiles (McGee+ 1986)
J/ApJS/101/41 : SMC and Bridge extended catalog (Bica+ 1995)
J/MNRAS/339/105 : Western Magellanic Bridge HI observations (Muller+, 2003)
J/ApJ/658/345 : CRIc photometry of Magellanic Bridge Fields (Harris 2007)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- [NHK2007] Sequential number
5- 6 I2 h RAh Right ascension (J2000)
8- 9 I2 min RAm Right ascension (J2000)
11- 15 F5.2 s RAs Right ascension (J2000)
17 A1 --- DE- Declination sign (J2000)
18- 19 I2 deg DEd Declination (J2000)
21- 22 I2 arcmin DEm Declination (J2000)
24- 27 F4.1 arcsec DEs Declination (J2000)
29- 33 F5.2 mag Jmag Johnson J magnitude
35- 38 F4.2 mag e_Jmag rms uncertainty on Jmag
40- 44 F5.2 mag Hmag Johnson H magnitude
46- 49 F4.2 mag e_Hmag rms uncertainty on Hmag
51- 55 F5.2 mag Ksmag Johnson Ks magnitude
57- 60 F4.2 mag e_Ksmag rms uncertainty on Ksmag
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 21-Jan-2009