J/AJ/123/387 VRI photometry of λ Ori star-forming region (Dolan+, 2002)
A photometric study of the young stellar population throughout the
λ Orionis star-forming region.
Dolan C.J., Mathieu R.D.
<Astron. J. 123, 387 (2002)>
=2002AJ....123..387D 2002AJ....123..387D
ADC_Keywords: Stars, pre-main sequence ; Photometry, VRI
Keywords: stars: formation - stars: pre-main-sequence
Abstract:
We present VRI photometry of 320,917 stars with 11≲R≲18 throughout
the λ Ori star-forming region. Using the more spatially limited
spectroscopic surveys of Dolan & Mathieu (1999, Cat. J/AJ/118/2409,
2001, Cat. J/AJ/121/2124) to define the color-magnitude domain of
young low-mass members of the association and removing statistically
the field stars in this domain, we use our photometry to identify a
representative pre-main-sequence (PMS) population throughout the
interior of the molecular ring.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
phot.dat 84 320917 VRI Photometry (table 4)
fields.dat 75 83 The targets observed (tables 1 and 3)
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See also:
J/AJ/118/2409 : VRI photometry of λ Ori PMS stars (Dolan+, 1999)
J/AJ/121/2124 : λ Ori pre-main-sequence stars photometry (Dolan+, 2001)
Byte-by-byte Description of file: phot.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- --- [lOri]
6- 22 A17 --- lOri Object identification, JHHMMSS.s+DDMMSSa (1)
24- 29 F6.3 mag Vmag The V band magnitude (2)
31- 36 F6.3 mag Rmag The RC band magnitude (2)
38- 43 F6.3 mag Imag The IC band magnitude (2)
45- 46 I2 h RAh Hour of Right Ascension (J2000)
48- 49 I2 min RAm Minute of Right Ascension (J2000)
51- 56 F6.3 s RAs Second of Right Ascension (J2000)
58- 59 I2 deg DEd Degree of Declination (J2000)
61- 62 I2 arcmin DEm Arcminute of Declination (J2000)
64- 68 F5.2 arcsec DEs Arcsecond of Declination (J2000)
70- 84 A15 --- Fld Field number
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Note (1): The identifier, lOri JHHMMSS.s+DDMMSSa, is constructed from the
USNO-A2.0 (Cat. I/252) coordinates.
For the 110 stars where this identifier is not unique, we have
appended an `a' for the westmost or a `b' for the eastmost star
to distinguish between them.
Note (2): The mean photometric error is 0.032 (12<R<16),
0.069 (16<R<17), or 0.12 (17<R<18) mag as described in the text.
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Byte-by-byte Description of file: fields.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Fld Target field number
5- 6 I2 h RAh Right Ascension (J2000) of field center (hr)
8- 9 I2 min RAm Right Ascension (J2000) of field center (min)
11- 12 I2 s RAs Right Ascension (J2000) of field center (sec)
14 A1 --- DE- Declination (J2000) of field center (sign)
15- 16 I2 deg DEd Declination (J2000) of field center (deg)
18- 21 F4.1 arcmin DEm Declination (J2000) of field center (arcmin)
23- 33 A11 "YYYY-MMM-DD" Night ? Observation date (blank = not observed)
35- 75 A41 --- Com Comments about observing conditions
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History:
From electronic version of the journal
* 22-Jul-2002: Added the list of fields
(End) Greg Schwarz [AAS], Patricia Bauer [CDS] 28-Mar-2002