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RR LYRAE VARIABLE STARS: PULSATIONAL CONSTRAINTS RELEVANT TO THE OOSTERHOFF CONTROVERSY

G. Bono·F. Caputo·V. Castellani·M. Marconi
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Abstract

A solution to the old Oosterhoff controversy is proposed on the basis of a new theoretical pulsational scenario concerning RR Lyrae cluster variables (Bono and coworkers). We show that the observed constancy of the lowest pulsation period in both Oosterhoff type I (OoI) and Oosterhoff type II (OoII) prototypes (M3, M15) can be easily reproduced only by assuming the canonical evolutionary horizontal-branch luminosity levels of these Galactic globular clusters and therefore by rejecting the Sandage period shift effect (SPSE).

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G. Bono, F. Caputo, V. Castellani, M. Marconi. 1995-06-01. RR LYRAE VARIABLE STARS: PULSATIONAL CONSTRAINTS RELEVANT TO THE OOSTERHOFF CONTROVERSY. https://doi.org/10.1086/309610

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