NGC 6535 BV CCD photometry

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 =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. ata@noao.edu Kitt Peak National Observatory, National Optical Astronomy Observatories, P.O. Box 26732, Tucson, Arizona 85726-6732

Identifier
Source https://dc.g-vo.org/rr/q/lp/custom/CDS.VizieR/J/PASP/106/404
Related Identifier https://cdsarc.cds.unistra.fr/viz-bin/cat/J/PASP/106/404
Related Identifier http://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/PASP/106/404
Metadata Access http://dc.g-vo.org/rr/q/pmh/pubreg.xml?verb=GetRecord&metadataPrefix=oai_b2find&identifier=ivo://CDS.VizieR/J/PASP/106/404
Provenance
Creator SARAJEDINI A.
Publisher CDS
Publication Year 1997
Rights https://cds.unistra.fr/vizier-org/licences_vizier.html
OpenAccess true
Contact CDS support team <cds-question(at)unistra.fr>
Representation
Resource Type Dataset; AstroObjects
Discipline Astrophysics and Astronomy; Natural Sciences; Observational Astronomy; Physics; Stellar Astronomy