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J/A+A/331/70        JKVI photometry of NGC 6553 stars   (Guarnieri+ 1998)

Infrared Array Photometry of Bulge Globular Clusters. I. Combined ground based JK and HST VI Photometry of NGC 6553 Guarnieri M.D., Ortolani S., Montegriffo P., Renzini B., Barbuy B., Bica E., Moneti A. <Astron. Astrophys. 331, 70 (1998)> =1998A&A...331...70G (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, globular ; Stars, blue ; Photometry, infrared Keywords: globular clusters: NGC 6553 - Galaxy: center - blue stragglers - HR diagram Abstract: JK infrared photometry for the bulge globular cluster NGC 6553, combined with high resolution visual VI observations are presented and discussed in connection with the bulge metal rich population. The infrared data were taken with IRAC2 at ESO 2.2m telescope while the optical counterparts are from Hubble Space Telescope (HST). We find a mean magnitude for the horizontal branch of VHB=16.92, and KHB=12.42±0.01. Assuming a reddening of E(B-V)=0.7, the mean distance modulus is (m-M)0=13.6 giving an heliocentric distance of 5.2Kpc. This distance is slightly higher than that previously published by Ortolani et al. (1990A&A...236..362O, hereafter OBB90). The brightest giants have been detected at K∼6.5 and (V-K)=13.10 transforming to MK=-7.34 and (V-K)0=11.20, which are exceptionally high values for a globular cluster. The metallicity has been found to be consistent with previous values and an average of [Fe/H]=-0.22±0.05 has been adopted. The helium abundance estimated via the R' method yields Yp∼0.28±0.03. Objects: ---------------------------------------------------------- RA (2000) DE Designation(s) ---------------------------------------------------------- 18 09 15.6 -25 54 28 NGC 6553 ---------------------------------------------------------- File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file appen.dat 41 1426 VIJK photometry of 1426 stars
Byte-by-byte Description of file: appen.dat
Bytes Format Units Label Explanations
1- 5 I5 --- No [1/48688]+ Sequential number (1) 7- 11 F5.2 mag Vmag HST V magnitude 13- 17 F5.2 mag Imag HST I magnitude 19- 23 F5.2 mag Jmag IRAC2 J magnitude 25- 29 F5.2 mag Kmag IRAC2 K magnitude 31- 35 F5.1 pix Xpos HST X position (2) 37- 41 F5.1 pix Ypos HST Y position
Note (1): No 1 to 2197 belong to the WFPC2 PC chip 20001 to 26240 to the WFPC2 chip#2 30001 to 39545 to the WFPC2 chip#3 40001 to 48688 to the WFPC2 chip#4 Note (2): X position transformed to the IRAC2 reference frame
History: Prepared via OCR at CDS from the manuscript.
(End) Patricia Bauer [CDS] 09-Sep-1997
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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