Changes in the Period of the Population II Cepheid CC Lyr.

The reduction of all the available photometry for the Cepheid CC Lyr has allowed its diagram spanning a time interval of 124 years to be constructed. The data obtained provide evidence for the existence of large random fluctuations in the period (). A formal fitting of the residuals has made it possible to estimate the rate of secular increase in the period, s yr . The pulsation stability test proposed by Lombard and Koen (1993) has confirmed that the increase in the period is real. [ABSTRACT FROM AUTHOR]