J/A+A/384/890 BVRIHalpha photometry of NGC 2244 X-ray stars (Berghoefer+, 2002) ================================================================================ Optical properties of X-ray selected stars in NGC 2244 in the Rosette Nebula. Berghoefer T.W., Christian D.J. =2002A&A...384..890B (SIMBAD/NED BibCode) ================================================================================ ADC_Keywords: Clusters, open ; X-ray sources ; Photometry, UBVRI Keywords: galaxy - open clusters and associations: individual: NGC 2244 - stars: early-type - stars: late-type - stars: activity - stars: pre-main sequence - X-ray: stars Abstract: We present high spatial resolution optical photometry of NGC 2244 in the Rosette Nebula using the NOAO MOSAIC Imager at Kitt Peak. We obtained BVIR and H{alpha} images of the central cluster and surrounding nebulae, and present results for 138 sources selected from X-ray observations with the ROSAT PSPC and HRI. Color-magnitude diagrams of the cluster show a large number of the stars are still undergoing contraction onto the main sequence. The faintest X-ray selected cluster members have the highest X-ray-to-optical luminosities (L_x_~>7x10^30^erg/s; L_x_/L_bol_=~10^-2^ to 10^-3^) and indicate they are a population of young active late-type stars. H{alpha} emission from the X-ray emitters is also remarkable. We have extended the detections of PMS stars in NGC 2244 well into the ran ge of K spectral types. While most of the cluster stars are located in the color-magnitude diagrams in between the ZAMS and the 3Myrs isochrone, significantly younger low mass stars exist and confirm earlier reports that star formation is still going on in the Rosette Nebula/NGC 2244 region. File Summary: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- ReadMe 80 . This file table3.dat 146 138 Summary of optical and X-ray properties of stars detected in the ROSAT PSPC and HRI observations of the Rosette Nebula table3.tex 224 246 LaTeX version of table 3 -------------------------------------------------------------------------------- See also: IX/30 : Second ROSAT PSPC Catalog (ROSAT, 2000) IX/28 : ROSAT HRI Pointed Observations (1RXH) (ROSAT Team, 2000) Table 1: ROSAT observation log. -------------------------------------------------------------------------------- ROR Detector Date Exposure(s) -------------------------------------------------------------------------------- WG200196P PSPC Apr. 2, 1992 4300 Oct. 5, 1993 12850 WG202155H HRI Apr. 5-11, 1996 18800 -------------------------------------------------------------------------------- Byte-by-byte Description of file: table3.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 3 I3 --- Seq Running number 5- 6 I2 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 17- 18 I2 deg DEd Declination (J2000) 20- 21 I2 arcmin DEm Declination (J2000) 23- 26 F4.1 arcsec DEs Declination (J2000) 28- 32 F5.1 arcsec dRA ? Angular sep. of PSPC and Optical pos. in RA 34- 38 F5.1 arcsec dDec ? Angular sep. of PSPC and Optical pos. in DE 40- 44 F5.2 ct/ks CRpspc PSPC count rate 46- 49 F4.2 ct/ks e_CRpspc Error in PSPC count rate 51- 55 F5.2 [10-7W] logLpspc log of PSPC luminosity 57- 60 F4.2 [10-7W] e_logLpspc Error in PSPC luminosity 62- 66 F5.2 ct/ks CRhri HRI count rate (1) 68- 71 F4.2 ct/ks e_CRhri Error HRI count rate (1) 73- 77 F5.2 [10-7W] logLhri log of HRI luminosity 79- 82 F4.2 [10-7W] e_logLhri Error in logLhri 84- 88 F5.2 mag Bmag ? MOSAIC B magnitude 90- 94 F5.2 mag Vmag ? MOSAIC V magnitude 96-100 F5.2 mag Rmag ? MOSAIC R magnitude 102-106 F5.2 mag Imag ? MOSAIC I magnitude 108-112 F5.2 mag Hamag ? MOSAIC H{alpha} magnitude 114-146 A33 --- Rem Remarks -------------------------------------------------------------------------------- Note (1): Errors of 0.00 indicate a 3{sigma} upper limit for HRI count rate -------------------------------------------------------------------------------- Acknowledgements: Thomas Berghoefer ================================================================================ (End) Patricia Bauer [CDS] 15-Mar-2002