Hostname: page-component-7bb8b95d7b-wpx69 Total loading time: 0 Render date: 2024-10-04T13:53:07.520Z Has data issue: false hasContentIssue false

White Dwarf Candidates in the Globular Cluster NGC 6752

Published online by Cambridge University Press:  14 August 2015

Harvey B. Richer*
Affiliation:
Department of Geophysics and Astronomy, University of British Columbia, Vancouver, Canada

Extract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Recently (Richer 1978, hereafter Paper I), the results of a search for faint blue objects in and around the globular cluster NGC 6752 were reported. The aim of the program was to isolate a sample of white dwarf candidates in this cluster which could then be studied in further detail. The statistics of this survey are as follows: (1) 68 objects found with B ≤ 22.7 and (U-B) ≤ −0.4 within 20 arcmin of the cluster center; (2) of the 68, 36 also had a measurable V magnitude; (3) of these 36, only 11 lay in the area of the color-color diagram occupied by white dwarfs, while the remaining 25 were generally well above the black body line and are probably QSOs or peculiar blue stellar objects; (4) of these 11, 7 are within 14 arcmin of the cluster center and hence have a probability of greater than 50% of being cluster members (King et al. 1968); (5) CTIO 4-m SIT vidicon spectra were obtained of 5 of these 7 candidates, 4 of which appear to be white dwarfs and 1 of which is a QSO with Z = 2. Table 1 lists the derived properties of the 4 white dwarfs assuming that they belong to NGC 6752. The star names are from Paper 1.

Type
August 30 Globular Clusters
Copyright
Copyright © Reidel 1980 

References

Greenstein, J.L., and Sargent, A.I.: 1974, Astrophys. J. Suppl. 28, 157.CrossRefGoogle Scholar
King, I.R., Hedemann, E., and Hodge, S.M.: 1968, Astron. J. 73, 456.Google Scholar
Richer, H.B.: 1978, Astrophys. J. (Letters) 224, L9.Google Scholar
Richer, H.B.: 1979, in Van Horn, H.M. and Weidemann, V. (eds.). Proc. of IAU Colloquim 53: White Dwarfs and Variable Degenerate Stars (in press).Google Scholar