UIT Detection of Hot Stars in the Globular Cluster NGC362

Abstract

We used the Ultraviolet Imaging Telescope during the March 1995 Astro-2 mission to obtain a deep far-UV image of the globular cluster NGC 362, which was formerly thought to have an almost entirely red horizontal branch (HB). 84 hot (T_eff > 8500 K) stars were detected within a radius of 8'.25 of the cluster center. Of these, 43 have FUV magnitudes consistent with HB stars in NGC 362, and at least 34 are cluster members. The number of cluster members is made uncertain by background contamination from blue stars in the Small Magellanic Cloud (SMC). There are six candidate supra-HB stars which have probably evolved from the HB. We discuss the implications of these results for the production of hot blue stars in stellar populations.

10 pages AASLaTeX including one postscript figure and one compressed bitmap, .jpg format. To appear in Ap. J. Letters. Postscript version also available at http://www.astro.virginia.edu/~bd4r/

References in corpus (1)

• Peculiar Multimodality on the Horizontal Branch of the Globular Cluster NGC 2808

Cited by in corpus (8)

• Far-Ultraviolet Radiation from Elliptical Galaxies
• Multimodal Distributions along the Horizontal Branch
• Hot Stars in Globular Cluster - A Spectroscopist's View
• HST Observations of New Horizontal Branch Structures in the Globular Cluster omega Centauri
• Age as the Second Parameter in NGC 288/NGC 362? II. The Horizontal Branch Revisited
• The Swift UVOT Stars Survey: I. Methods and Test Clusters
• Globular Clusters UVIT Legacy Survey (GlobULeS) I. FUV-optical Color-Magnitude Diagrams for Eight Globular Clusters
• Stellar populations of the globular cluster NGC 5053 investigated using AstroSat-Ultra Violet Imaging Telescope