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RR Lyrae stars in the outer region of the globular cluster M3: a shortage of long periods at r ~ 3.5 to 6 arcmin ?

D. J. Butler
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Abstract

An analysis of the radial distribution of ab-type RR Lyrae star periods in the outer region of the globular cluster M3 at r >= 0.83 arcmin has been performed. That analysis points towards a real shortage of stars with long periods in the radial distance range 3.5 to 6 arcmin (or about 7 to 12 core radii). A brief discussion is presented. The origin of the phenomenon remains an open question.

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D. J. Butler. 2004-04-07. RR Lyrae stars in the outer region of the globular cluster M3: a shortage of long periods at r ~ 3.5 to 6 arcmin ?. https://doi.org/10.1051/0004-6361%3A20040137

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