J/PASP/106/404 NGC 6535 BV CCD photometry (Sarajedini, 1994)
CCD photometry of the galactic globular cluster NGC6535 in the B and V passbands
SARAJEDINI A.
<Publ. Astron. Soc. Pac. 106, 404 (1994)>
=1994PASP..106..404S 1994PASP..106..404S (SIMBAD/NED Reference)
ADC_Keywords: Clusters, globular; Photometry, CCD
Abstract:
The first CCD color-magnitude diagram (CMD) in B and V is presented for
the Galactic globular cluster NGC 6535. From this CMD, which extends
below the main-sequence turnoff, we draw the following conclusions:
(1) The horizontal branch (HB) is predominantly blue in nature with
no RR Lyrae variables known to be cluster members. Nonetheless, based
on a comparison with clusters which have blue HBs and RR Lyraes
(M15 and M79), we infer a mean HB magnitude of <V(RR)≥15.73±0.11
for NGC 6535. (2) Again, via a direct comparison with the blue HBs of
M15 and M79, we derive a cluster reddening of E(B-V)=0.44±0.02.
(3) When combined with the apparent color of the red-giant branch at
the level of the HB, (B-V)g=1.18±0.02, the derived reddening yields
a metal abundance of [Fe/H]=-1.85±0.10, similar to that of NGC 6397.
(4) Application of the Delta(V(TO-HB)) and Delta((B-V)(SGB-TO)) cluster
dating techniques reveals no perceptible age difference between NGC 6535
and NGC 6397. (5) A significant population of nine blue-straggler
candidates is detected in NGC 6535. However, this is too few to
facilitate a meaningful analysis of their radial distribution.
Addresses:
Sarajedini A.
Kitt Peak National Observatory, National Optical Astronomy Observatories,
P.O. Box 26732, Tucson, Arizona 85726-6732
Objects:
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RA (2000) DE Designation(s)
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18 03 50.6 -00 17 49 NGC 6535 = C 1801-003
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 38 932 Photometry of NGC 6535
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Byte-per-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- ID Star number
7- 13 F7.2 pix X X CCD coordinate
16- 22 F7.2 pix Y Y CCD coordinate
25- 29 F5.2 mag Vmag Visual magnitude
32- 35 F4.2 mag B-V B-V color
38- 38 I1 --- o_Vmag Number of observations
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Origin: AAS CD-ROM series, Volume 2, 1994
(End) Lee Brotzman [ADS] 21-May-1994, Patricia Bauer [CDS] 03-Nov-1994