Abstract
Recent Hipparcos results have lent support to the idea that RR Lyrae variables in the halo field and in globular clusters differ in luminosity by ≈ 0.2 mag. In this Letter, we study the pulsation properties of RR Lyrae variables in clusters with distances determined via main-sequence fitting to Hipparcos parallaxes for field subdwarfs and compare them with the properties of field variables also analyzed with Hipparcos. We show that the period-temperature distributions for field and cluster variables are essentially indistinguishable, thus suggesting that there is no significant difference in luminosity between them.
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