J/PASJ/55/635 Chandra observations of Monoceros R2 (Nakajima+, 2003)
X-ray observation on the Monoceros R2 star-forming region with the
Chandra ACIS-I array.
Nakajima H., Imanishi K., Takagi S., Koyama K., Tsujimoto M.
<Publ. Astron. Soc. Jap., 55, 635 (2003)>
=2003PASJ...55..635N 2003PASJ...55..635N
ADC_Keywords: Molecular clouds ; X-ray sources ; Infrared sources ; YSOs
Keywords: ISM: individual (Monoceros R2) - ISM: stars - stars: formation -
X-rays: stars
Abstract:
We report on the results of the Chandra ACIS-I observation on the
central region of the Monoceros R2 cloud (Mon R2), a high-mass
star-forming region (SFR) at a distance of 830pc. With a deep exposure
of ∼100ks, we detected 368 X-ray sources, ∼80% of which were
identified with the near-infrared (NIR) counterparts. We
systematically analyzed the spectra and time variability of most of
the X-ray emitting sources and provided a comprehensive X-ray source
catalog for the first time. Using the J-, H- and K-bands magnitudes of
the NIR counterparts, we estimated the evolutionary phase (classical T
Tauri stars and weak-lined T Tauri stars) and the mass of the X-ray
emitting sources, and analyzed the X-ray properties as a function of
the age and mass.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 74 368 Chandra X-ray sources and stellar counterparts
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See also:
B/chandra : The Chandra Archive Log (CXC, 2002)
II/241 : 2MASS Catalog Intermediate Data Release (IPAC/UMass, 2000)
J/ApJ/567/423 : CHANDRA obs. of YSOs in Monoceros R2 (Kohno+, 2002)
J/AJ/114/198 : The Monoceros R2 Cluster (Carpenter+ 1997)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- [NIT2003] Sequential number
5- 6 I2 h RAh Right ascension (J2000) (1)
8- 9 I2 min RAm Right ascension (J2000) (1)
11- 15 F5.2 s RAs Right ascension (J2000) (1)
17 A1 --- DE- Declination sign (J2000) (1)
18- 19 I2 deg DEd Declination (J2000) (1)
21- 22 I2 arcmin DEm Declination (J2000) (1)
24- 27 F4.1 arcsec DEs Declination (J2000) (1)
29- 35 F7.2 ct Count Background-subtracted X-ray photon counts in
the 0.5-10.0keV band.
37- 51 A15 --- XID X-ray identification (2)
53- 74 A22 --- NIRID NIR identification (3)
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Note (1): Coordinates are corrected to the 2MASS frame
Note (2): X-ray counterparts:
KKH: Kohno et al. (2002, Cat. J/ApJ/567/423), [KKH2002] NNN in Simbad
GMCF: Gregorio-Hetem et al. (1998A&A...331..193G 1998A&A...331..193G),
[GMC98] Mon X-NN in Simbad
Note (3): NIR counterparts:
CMDSH: Carpenter et al. (1997, Cat. J/AJ/114/198), [CMD97] NNNN in Simbad
2MASSI: 2MASS Point Source Catalog in the Second Incremental Data
Release, Cat. II/241
NIR source names such as d_N and IRS4 are from Beckwith et al.
(1976ApJ...208..390B 1976ApJ...208..390B, [BEB76] IRS N), Howard et al. (1994ApJ...425..707H 1994ApJ...425..707H,
[AW90] aW, [BEB76] IRS NWW), and Carpenter et al. (1997, Cat.
J/AJ/114/198). (i.e. d_N = [AW90] dN, IRS 4 = [BEB76] IRS 4 in Simbad)
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History:
* 08-May-2006: From electronic version of the journal
* 28-May-2009: For object 190, NIRID identification corrected
(End) James Marcout, Patricia Bauer [CDS] 21-Nov-2003