J/AJ/131/2959 Candidate low-mass PMS in 25 Orionis group (McGehee+, 2006)
The southern flanking fields of the 25 Orionis group.
McGehee P.M.
<Astron. J., 131, 2959-2966 (2006)>
=2006AJ....131.2959M 2006AJ....131.2959M
ADC_Keywords: Associations, stellar ; Stars, pre-main sequence ;
Stars, late-type ; Photometry, SDSS
Keywords: open clusters and associations: individual (25 Orionis) -
stars: formation - stars: late-type - stars: low-mass, brown dwarfs -
stars: pre-main sequence
Abstract:
The stellar group surrounding the Be (B1Vpe) star 25 Ori was
discovered to be a pre-main-sequence (PMS) population by the CIDA
Variability Survey of Orion (Cat. J/AJ/129/907) and subsequent
spectroscopy. We analyze Sloan Digital Sky Survey multiepoch
photometry to map the southern extent of the 25 Ori group and
characterize its PMS population. We compare this group to the
neighboring Orion OB1a and OB1b subassociations and to active star
formation sites (NGC 2068/NGC 2071) within the LDN 1630 dark cloud. We
find that the 25 Ori group has a radius of 1.4°, corresponding to
8-11pc at the distances of Orion OB1a and OB1b.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 71 506 Candidate low-mass PMS in the Orion equatorial
region
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See also:
J/AJ/129/907 : New Ori OB1 members (Briceno+, 2005)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- --- [SDSS]
6- 24 A19 --- SDSS Source name ([M2006] SDSS JHHMMSS.ss+DDMMSS.s
in Simbad) from SDSS low Galactic latitude
(see Finkbeiner et al., 2004AJ....128.2577F 2004AJ....128.2577F)
26- 32 F7.4 deg RAdeg Right Ascension in decimal degrees (J2000)
34- 40 F7.4 deg DEdeg Declination in decimal degrees (J2000)
42- 46 F5.2 mag gmag SDSS g band magnitude
48- 52 F5.2 mag rmag SDSS r band magnitude
54- 58 F5.2 mag imag SDSS i band magnitude
60- 64 F5.2 mag zmag SDSS z band magnitude
66- 69 F4.2 deg R Distance from the Be star 25 Ori
71 A1 --- TTS [CW] Weak-lined (W) or Classical (C) T Tauris (1)
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Note (1): Based on multi-band variability.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Marianne Brouty [CDS] 07-Jul-2008