J/A+A/570/A30 Hα emission-line stars in M42 (Pettersson+, 2014)
Hα emission-line stars in molecular clouds. II. The M42 region.
Pettersson B, Armond T. Reipurth B.
<Astron. Astrophys. 570, A30 (2014)>
=2014A&A...570A..30P 2014A&A...570A..30P
ADC_Keywords: Molecular clouds ; Stars, emission ; Stars, pre-main sequence ;
Photometry
Keywords: stars: emission-line - stars: formation - stars: pre-main sequence
Abstract:
We present a deep survey of H-alpha emission-line stars in the M42
region using wide-field objective prism films. A total of 1699 Hα
emission-line stars were identified, of which 1025 were previously
unknown, within an area of 5.5°x5.5° centred on the Trapezium
Cluster. We present H-alpha strength estimates, positions, and JHKs
photometry extracted from 2MASS, and comparisons to previous surveys.
The spatial distribution of the bulk of the stars follows the
molecular cloud as seen in CO and these stars are likely to belong to
the very young population of stars associated with the Orion Nebula
Cluster. Additionally, there is a scattered population of H-alpha
emission-line stars distributed all over the region surveyed, which
may consist partly of foreground stars associated with the young
NGC 1980 cluster, as well as some foreground and background dMe or Be
stars. The present catalogue adds a large number of candidate low-mass
young stars belonging to the Orion population, selected independently
of their infrared excess or X-ray emission.
Description:
We present H-α strength estimates for 1699 emission-line stars
in the M42 region. Positions and JHKs-photometry were extracted from
2MASS and mJmFm_N-photometry from the USNO-B or GSC 2.2 catalogue.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 114 1697 Hα emission-line stars in M42
notes.dat 101 69 Notes
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See also:
J/AJ/127/1117 : Halpha emission-line stars in NGC2264 (Reipurth+, 2004)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- ESOHa [576/1834]? ESO Hα number for newly
discovered stars only
5- 7 A3 --- m_ESOHa Multiplicity index on ESOHa (W+E, W, E)
8- 12 A5 --- GCVS Name in General Catalog of Variable Stars
(should be followed by Ori)
14- 19 A6 --- KisoHa Designation from Kiso H-α survey (1)
21- 23 I3 --- HBC ? Herbig and Bell catalogue (1988, Cat. V/73)
25- 31 A7 --- Haro Haro number with extensions (2)
33- 35 I3 --- PaCh ? Parsamian & Chavira (1982BITon...3...69P 1982BITon...3...69P,
in Simbad)
37- 44 A8 --- Other Other names (3)
46- 47 I2 h RAh Right Ascension J2000 (hours) (4)
49- 50 I2 min RAm Right Ascension J2000 (minutes) (4)
52- 56 F5.2 s RAs Right Ascension J2000 (seconds) (4)
58 A1 --- DE- Declination J2000 (sign) (4)
59- 60 I2 deg DEd Declination J2000 (degrees) (4)
62- 63 I2 arcmin DEm Declination J2000 (minutes) (4)
65- 68 F4.1 arcsec DEs Declination J2000 (seconds) (4)
70- 72 A3 --- Ha Hα emission-line strength (5)
74- 78 F5.2 mag mJ ? USNO-B or GSC 2.2 mJ magnitude (6)
80- 84 F5.2 mag mF ? USNO-B or GSC 2.2 mF magnitude (6)
86- 90 F5.2 mag mN ? USNO-B or GSC 2.2 mN magnitude (6)
92- 96 F5.2 mag Jmag ? 2MASS J magnitude (4)
98-102 F5.2 mag Hmag ? 2MASS H magnitude (4)
104-108 F5.2 mag Ksmag ? 2MASS Ks magnitude (4)
110-114 A5 --- Notes Notes to individual objects, in notes.dat file
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Note (1): Kiso H-α catalog (Wiramihardja et al. 1993PASJ...45..643W 1993PASJ...45..643W):
* 48-NN is <Kiso A-1048-NN> in Simbad,
* 75-NNN is <Kiso A-0975 NN> in Simbad and
* 76-NNN is <Kiso A-0976-NNN> in Simbad.
Note (2): Haro catalogs:
* Haro 4-1 to 4-255 from Haro catalogue (1953ApJ...117...73H 1953ApJ...117...73H),
* Haro 4-256 to 4-495 from Parsamian and Chavira (1982BITon...3...69P 1982BITon...3...69P) and
* Haro 5-1 to 5-98 from Haro & Moreno (1953BOTT....1g..11H 1953BOTT....1g..11H).
Note (3): An asterisk means a star also listed in Szegedi-Elek et al.
(2013ApJS..208...28S 2013ApJS..208...28S)
Note (4): Positions and magnitudes extracted from the 2MASS All-Sky Catalog.
Note (5): The H-α strength is defined so 1 is weak emission against
a strong continuum and 5 is strong emission against a weak or invisible
continuum. Hyphenated values may represent either variability and/or
uncertainty in the estimate, and a '+' indicates resolved spectra but
unresolved DSS2 image.
Note (6): The magnitudes mJ, mF, and mN are from the photographic
blue (IIIaJ emulsion), red (IIIaF emulsion), and infrared (IV-N emulsion)
digitised sky surveys extracted from USNO-B catalogue or from GSC 2.2.
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Byte-by-byte Description of file: notes.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Note [1/69] Note number
4-101 A98 --- Text Text of the note
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Acknowledgements:
Bertil Pettersson, bertil.pettersson(at)physics.uu.se
References:
Reipurth et al., Paper I, 2004AJ....127.1117R 2004AJ....127.1117R, Cat. J/AJ/127/1117
History:
* 10-Oct-2014: original version
* 26-Nov-2014: table2.dat and notes.dat files corrected (from author)
(End) Patricia Vannier [CDS] 01-Sep-2014