SOAR Adaptive Optics Observations of the Globular Cluster NGC6496

TL;DR

This paper presents high-quality adaptive optics photometry of the globular cluster NGC 6496, deriving its fundamental parameters such as distance, age, metallicity, and classification, confirming previous findings with improved data quality.

Contribution

First high-quality adaptive optics BVRI photometry of NGC 6496 providing precise cluster parameters and supporting its disk classification.

Findings

Distance modulus $ ext{(m-M)}_V = 15.71 \, mag$

Age of $10.5 \, Gyr$ from red clump analysis

Metallicity $ ext{[Fe/H]} = -0.65$ dex

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 is $\mMv = 15.71 \pm 0.02$\,mag and $\EVI = 0.28 \pm 0.02$\,mag. An age of $10.5 \pm 0.5$\,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 $\feh = -0.65$\,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.