J/other/NewA/10.325 2MASS observations of Be stars (Zhang+, 2005)
2MASS observations of Be stars.
Zhang P., Chen P.S., Yang H.T.
<New Astronomy, 10, 325 (2005)>
=2005NewA...10..325Z 2005NewA...10..325Z
ADC_Keywords: Stars, emission ; Stars, Be ; Photometry, infrared
Keywords: stars: emission-line, Be; infrared: stars
Abstract:
A catalogue of almost all known Galactic Be stars in the 2MASS
(II/246) database (1185 in total) and in the MSX (V/114) database
(225 in total) is presented in this paper. From the color-color
diagrams and spectral indexes, it is found that the IR excesses for
many samples are due to free-free and free-bound emission from the
ionized material around a Be star as suggested previously and that the
mean spectral index derived for the samples is 1.50±0.34 between J
to K bands and 1.14±0.42 between K to A bands, respectively.
However, it is also found that there are eight Be stars that have
large near infrared excess emission with spectral index values outside
the range expected for freefree and freebound emission. This is likely
attributed to circumstellar dust emission.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 141 1185 2MASS associations of Be stars
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See also:
III/67 : Catalogue of Be stars (Jaschek+, 1982)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
V/114 : MSX6C Infrared Point Source Catalog (Egan+ 2003)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Sequential number or Name (1)
13- 26 A14 --- SpType MK spectral type
28- 32 F5.2 mag Vmag V magnitude
35- 40 F6.3 mag B-V ? B-V colour index
42- 46 F5.3 arcsec r Distance between the position of Be star and
the position of the related 2MASS source
48- 49 I2 h RAh 2MASS Right ascension (J2000)
51- 52 I2 min RAm 2MASS Right ascension (J2000)
54- 58 F5.2 s RAs 2MASS Right ascension (J2000)
60 A1 --- DE- 2MASS Declination sign (J2000)
61- 62 I2 deg DEd 2MASS Declination (J2000)
64- 65 I2 arcmin DEm 2MASS Declination (J2000)
67- 70 F4.1 arcsec DEs 2MASS Declination (J2000)
72- 77 F6.3 mag Jmag 2MASS PSC J magnitude
78 A1 --- n_Jmag [#] # when Jmag is upper limit value
80- 84 F5.3 mag e_Jmag ? rms uncertainty on Jmag
86- 91 F6.3 mag Hmag 2MASS PSC H magnitude
92 A1 --- n_Hmag [#] # when Hmag is upper limit value
93- 97 F5.3 mag e_Hmag ? rms uncertainty on Hmag
99-104 F6.3 mag Kmag 2MASS PSC K magnitude
105 A1 --- n_Kmag [#] # when Kmag is upper limit value
107-111 F5.3 mag e_Kmag ? rms uncertainty on Kmag
113-117 F5.3 mag AV ? Interstellar extinction at visual wavelength
119-123 F5.2 --- alpha(J-K) ? Power spectral index between J and K bands
125-129 F5.2 --- e_alpha(J-K) ? rms uncertainty on alpha(J-K)
131-135 F5.3 mag Amag ? A magnitude calculated from the flux at
A band (8.3um) in MSX
137-141 F5.2 --- alpha(K-A) ? Power spectral index between K and A bands
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Note (1): Number (Recno in VizieR, [JE82] NNNN) or identification in the
Catalogue of Be stars (Jaschek and Egret, 1982, Cat. III/67).
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 20-Jun-2006