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J/A+A/355/651    HRI observations of PMS stars in NGC 2264    (Flaccomio+, 2000)

HRI observations of PMS stars in NGC 2264. Flaccomio E., Micela G., Sciortino S., Damiani F., Favata F., Harnden F.R.Jr, Schachter J. <Astron. Astrophys. 355, 651 (2000)> =2000A&A...355..651F
ADC_Keywords: Clusters, open ; Stars, pre-main sequence ; X-ray sources Keywords: stars: coronae - stars: formation - stars: luminosity function, mass function - stars: pre-main sequence - Galaxy: open clusters and associations: individual: NGC 2264 - X-rays Abstract: We analyze six ROSAT HRI observations pointed toward the Star Forming Region (SFR) NGC 2264. Three are pointed to the southern star formation core, the other three about 20' to the north. We detect 169 X-ray sources, ∼95% of which are likely to be Pre Main Sequence (PMS) stars, significantly enlarging the known population of the SFR in the area covered by the observations. Using published BVRI photometry we place the X-ray sources with well defined optical counterparts on the HRI diagram and estimate their masses and ages. Our comparison of the mass function and age distribution of the X-ray sources with results previously obtained for NGC 2264, demonstrates that deep X-ray observations provide, at least in this case, a very efficient method of selecting SFR members and does not introduce stronger biases than other methods. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table3.dat 134 169 List of detected X-ray sources table4.dat 45 124 Counterparts of uniquely identified X-ray sources
See also: IX/28 : ROSAT HRI Pointed Observations (1RXH) (ROSAT Team, 2000) Byte-by-byte Description of file: table3.dat
Bytes Format Units Label Explanations
1- 3 I3 --- [FMS2000] Source name ([FMS2000] XNNN in Simbad) 4 A1 --- n_[FMS2000] [*] *: denotes unique counterparts 6 I1 h RAh Right ascension (J2000) 8- 9 I2 min RAm Right ascension (J2000) 11- 14 F4.1 s RAs Right ascension (J2000) 16 A1 --- DE- Declination sign (J2000) 17 I1 deg DEd Declination (J2000) 19- 20 I2 arcmin DEm Declination (J2000) 22- 25 F4.1 arcsec DEs Declination (J2000) 27- 31 F5.2 ct/ks CRMax Maximum count rate 33- 35 F3.1 ct/ks e_CRMax rms uncertainty on CRMax 37 A1 --- l_CRMin Limit flag on CRMin 38- 42 F5.2 ct/ks CRMin Minimum count rate 44- 46 F3.1 ct/ks e_CRMin ? rms uncertainty on CRMin 48 A1 --- l_<logLX> Limit flag on <logLX> 49- 53 F5.2 [10-7W] <logLX> Maximum likelihood X-ray luminosity 55- 59 F5.1 --- SNR Signifiance of source detection 61- 62 I2 --- Pvar ? Probability of the source being variable 64-134 A71 ---- Ident Suggested optical counterparts (1)
Note (1): We attempted identifications using stars from the following works: WNNN = Walker, 1956ApJS....2..365W (NGC 2264 NNN) VNNN = Vasilevskis et al., 1965AJ.....70..797V (Cl* NGC 2264 Vas NNN) HNN = Herbig, 1954ApJ...119..483H (Em* LkHA NN) MNNN = Marcy, 1980AJ.....85..230M (Em* LkHA NNN) ONNN = Ogura, 1984PASJ...36..139O (KHA NNN) SNNN = Sung et al., 1997AJ....114.2644S (Cl* NGC 2264 SBL NNN) FNNN = Flaccomio et al., 1999, Cat. J/A+A/345/521 (Cl* NGC 2264 FMS NNN) MXNNN = Young (private communication) Notes following the object number are: b = part of a visual double system, unresolved by the other authors m = denotes that the counterpart is reported as a NGC 2264 member in the cited paper
Byte-by-byte Description of file: table4.dat
Bytes Format Units Label Explanations
1- 3 I3 --- [FMS2000] Source name ([FMS2000] XNNN in Simbad) 5- 9 F5.2 mag Vmag ? V magnitude 10 A1 --- n_Vmag [ab] V magnitude origin if not that specified in Ref (1) 12- 16 F5.2 mag B-V ? B-V colour index 17 A1 --- n_B-V [ab] B-V colour origin if not that specified in Ref (1) 19- 23 F5.2 mag V-I ? V-I colour index 24 A1 --- n_V-I [bc] V-I colour origin if not that specified in Ref (1) 26- 31 A6 --- SpType MK spectral type 32 A1 --- n_SpType [b] Spectral type origin if not that specified in Ref (1) 34- 37 F4.2 [K] logTeff ? Effective temperature 39- 43 F5.2 [solLum] log(Lbol) ? Bolometric luminosity 45 A1 --- Ref [SF] Reference for reported photometry (1)
Note (1): References as follows: a = Data from Sagar & Joshi (1983MNRAS.205..747S) b = Data from Perez (1987PASP...99.1050P) c = Data from Cousin (1980, South African Astronomical Observatory Circular 1, 234) S = Sung et al., 1997AJ....114.2644S F = Flaccomio et al., 1999, Cat. J/A+A/345/521
History: Prepared via OCR at CDS.
(End) James Marcout, Patricia Bauer [CDS] 07-Jan-2002
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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