RR Lyrae variables in M5 as a test of pulsational theory

We present B and V CCD photometry for variables in the cluster central regi on, adding new data for 32 variables and giving suitable light curves, mean magnitudes and corrected colours for 17 RR Lyrae variables. Adding the dat a given in this paper to similar data that have already appeared in the lit erature, we discuss a sample of 42 variables, as given by 22 RRab and 20 RR c, in the light of recent predictions from pulsational theories. We find th at the observational evidence concerning M5 pulsators appears in marginal d isagreement with predictions concerning the colour of the first overtone bl ue edge (FOBE), whereas a clear disagreement appears between the zero-age h orizontal branch (ZAHB) luminosities predicted through evolutionary and pul sational theories.