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J/ApJ/625/156       FUV-NUV observations of NGC 2808            (Dieball+, 2005)

Far-ultraviolet observations of the globular cluster NGC 2808 revisited: blue stragglers, white dwarfs, and cataclysmic variables. Dieball A., Knigge C., Zurek D.R., Shara M.M., Long K.S. <Astrophys. J., 625, 156-166 (2005)> =2005ApJ...625..156D
ADC_Keywords: Clusters, globular ; Stars, blue ; Stars, white dwarf ; Stars, variable ; Photometry, HST ; Ultraviolet Keywords: blue stragglers - globular clusters: individual (NGC 2808) - novae, cataclysmic variables - white dwarfs Abstract: We present a reanalysis of far-ultraviolet (FUV) observations of the globular cluster NGC 2808 obtained with the Hubble Space Telescope. These data were first analyzed by Brown and coworkers (2001, Cat. J/ApJ/562/368), with an emphasis on the bright, blue horizontal-branch (HB) stars in this cluster. Here, our focus is on the population of fainter FUV sources, which include white dwarfs (WDs), blue stragglers (BSs), and cataclysmic variables (CVs). Description: NGC 2808 was observed with the Space Telescope Imaging Spectrograph (STIS) on board the HST in 2000 January-February. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 109 521 Catalog of all FUV-NUV sources
See also: J/ApJ/562/368 : UV photometry in NGC 2808 (Brown+, 2001) J/A+A/391/945 : HST photometry of 74 galactic globular clusters (Piotto+ 2002) J/A+AS/84/59 : Photometry of NGC 2808 (Ferraro+, 1990) J/A+A/417/597 : Radial velocities in 4 globular clusters (Recio-Blanco+, 2004) Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 3 I3 --- Seq Running identification number 5 I1 h RAh Hour of Right Ascension (J2000.0) (1) 7- 8 I2 min RAm Minute of Right Ascension (J2000.0) (1) 10- 14 F5.3 s RAs Second of Right Ascension (J2000.0) (1) 16 A1 --- DE- Sign of the Declination (J2000.0) (1) 17- 18 I2 deg DEd Degree of Declination (J2000.0) (1) 20- 21 I2 arcmin DEm Arcminute of Declination (J2000.0) (1) 23- 28 F6.3 arcsec DEs Arcsecond of Declination (J2000.0) (1) 30- 35 F6.3 mag FUVmag F25QTZ (1590Å) far-UV band magnitude 37- 41 F5.3 mag e_FUVmag Error on FUVmag 43- 48 F6.3 mag NUVmag ? F25CN270 (2700Å) near-UV band magnitude 50- 54 F5.3 mag e_NUVmag ? Error on NUVmag 56- 61 F6.3 mag DFUV ? Difference between Brown et al. (2001, Cat. J/ApJ/562/368) and this paper's FUV photometry 63- 68 F6.3 mag DNUV ? Difference between Brown et al. (2001, Cat. J/ApJ/562/368) and this paper's NUV photometry 70- 74 F5.2 arcsec Rad Distance to the cluster center (2) 76- 78 I3 --- Brown ? Identification number from Brown et al. (2001, Cat. J/ApJ/562/368) 80- 84 I5 --- Piotto ? Identification number from Piotto et al. (2002, Cat. J/A+A/391/945), Cl* NGC 2808 Piotto NNNNN in Simbad 86- 91 F6.3 mag Vmag ? The V band magnitude 93- 98 F6.3 mag Bmag ? The B band magnitude 100-109 A10 --- Com Additional comments (3)
Note (1): Our α δ coordinates are based on the (J2000.0) coordinate system given by the FITS-headers, but have been shifted to achieve the best match to the Brown et al. (2001, Cat. J/ApJ/562/368) coordinates. This required offsets of -0.13" in α and -0.6" in δ, after which the rms differences between our coordinates and Brown et al.'s are only 0.006" in α and 0.048" in δ. However, as noted in Brown et al. although the relative astrometry is very accurate, the error in the absolute astrometry is much larger (∼1-2"). Note (2): Using star number counts, we determined the cluster center at α=9:12:2.96 and δ=-64:51:47.78 (J2000.0). Note (3): Additional comments, defined as follows: a = The tolerance radius for matching these sources in FUV and NUV was increased from 1.5 to 2 pixels. n = These pairs were added by hand, see text for details. e = These stars show a somewhat elongated shape on the FUV mosaic and are located mainly in its outer regions. v = Good variable candidate, see text for details. pv = Possible variable candidate, but too few measurements for a reliable statement. nv = Unsure variable candidate, measurements on the single images agree within the errors. pv-f = Unsure variable candidate: faint companion to a bright star. Measurements on the single images are extremely difficult and thus not very reliable.
History: From electronic version of the journal
(End) Greg Schwarz [AAS], Marianne Brouty [CDS] 23-Nov-2005
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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