Photometric study of the x-ray globular cluster NGC 6624

Journal Article · Fri Sep 01 04:00:00 EDT 1978 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/156386· OSTI ID:6879254

Liller, M H; Carney, B W

We present a revised color-magnitude diagram of NGC 6624, a globular cluster coincident with the bursting X-ray source 3U 1820--30. The horizontal branch lies at V=16.05 mag; with the adopted reddening of 0.25 mag, we determine a revised distance of 8.3 +- 1.2kpc. The (m/H) derived from the slope of the giant branch is -0.7, which makes NGC 6624 one of the more metal-rich clusters in the Galaxy. The one RR Lyrae variable star in the area may be a field star; a red variable near the cluster is probably a member.

• Research Organization: Harvard-Smithsonian Center for Astrophysics
• OSTI ID: 6879254
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 224:2; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640102 -- Astrophysics & Cosmology-- Stars & Quasi-Stellar
Radio & X-Ray Sources
640103* -- Astrophysics & Cosmology-- Quasi-Stellar
Radio
& X-Ray Sources-- (-1987)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
DISTANCE
GALAXIES
MILKY WAY
PHOTOMETRY
RADIATION SOURCES
STAR CLUSTERS
X-RAY EQUIPMENT
X-RAY SOURCES