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Title: Soar adaptive optics observations of the globular cluster NGC 6496

Abstract

We present high-quality BVRI photometric data in the field of globular cluster NGC 6496 obtained with the SOAR Telescope Adaptive Module (SAM). Our observations were collected as part of the ongoing SAM commissioning. The distance modulus and cluster color excess as found from the red clump are (m – M) {sub V} = 15.71 ± 0.02 mag and E(V – I) = 0.28 ± 0.02 mag. An age of 10.5 ± 0.5 Gyr is determined from the difference in magnitude between the red clump and the subgiant branch. These parameters are in excellent agreement with the values derived from isochrone fitting. From the color-magnitude diagram we find a metallicity of [Fe/H] = –0.65 dex and hence support a disk classification for NGC 6496. The complete BVRI data set for NGC 6469 is made available in the electronic edition of the Journal.

Authors:
 [1]; ;  [2]
  1. Southern Observatory for Astrophysical Research, Casilla 603, La Serena (Chile)
  2. Cerro Tololo Inter-American Observatory, Casilla 603, La Serena (Chile)
Publication Date:
OSTI Identifier:
22340081
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astronomical Journal (New York, N.Y. Online); Journal Volume: 145; Journal Issue: 6; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CLASSIFICATION; COLOR; COMMISSIONING; DATA; DIAGRAMS; DISTANCE; GALAXY CLUSTERS; METALLICITY; OPTICS; PHOTOMETRY; TELESCOPES

Citation Formats

Fraga, Luciano, Kunder, Andrea, and Tokovinin, Andrei, E-mail: lfraga@ctio.noao.edu, E-mail: lfraga@lna.br. Soar adaptive optics observations of the globular cluster NGC 6496. United States: N. p., 2013. Web. doi:10.1088/0004-6256/145/6/165.
Fraga, Luciano, Kunder, Andrea, & Tokovinin, Andrei, E-mail: lfraga@ctio.noao.edu, E-mail: lfraga@lna.br. Soar adaptive optics observations of the globular cluster NGC 6496. United States. doi:10.1088/0004-6256/145/6/165.
Fraga, Luciano, Kunder, Andrea, and Tokovinin, Andrei, E-mail: lfraga@ctio.noao.edu, E-mail: lfraga@lna.br. 2013. "Soar adaptive optics observations of the globular cluster NGC 6496". United States. doi:10.1088/0004-6256/145/6/165.
@article{osti_22340081,
title = {Soar adaptive optics observations of the globular cluster NGC 6496},
author = {Fraga, Luciano and Kunder, Andrea and Tokovinin, Andrei, E-mail: lfraga@ctio.noao.edu, E-mail: lfraga@lna.br},
abstractNote = {We present high-quality BVRI photometric data in the field of globular cluster NGC 6496 obtained with the SOAR Telescope Adaptive Module (SAM). Our observations were collected as part of the ongoing SAM commissioning. The distance modulus and cluster color excess as found from the red clump are (m – M) {sub V} = 15.71 ± 0.02 mag and E(V – I) = 0.28 ± 0.02 mag. An age of 10.5 ± 0.5 Gyr is determined from the difference in magnitude between the red clump and the subgiant branch. These parameters are in excellent agreement with the values derived from isochrone fitting. From the color-magnitude diagram we find a metallicity of [Fe/H] = –0.65 dex and hence support a disk classification for NGC 6496. The complete BVRI data set for NGC 6469 is made available in the electronic edition of the Journal.},
doi = {10.1088/0004-6256/145/6/165},
journal = {Astronomical Journal (New York, N.Y. Online)},
number = 6,
volume = 145,
place = {United States},
year = 2013,
month = 6
}
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