NDLI: A search for evolutionary period variations of Cepheids using the Harvard plates: V396 Cyg

Content Provider	Springer Nature Link
Author	Berdnikov, L. N. Pastukhova, E. N.
Copyright Year	2012
Abstract	We obtained 503 photographic brightness estimates for the long-period classical Cepheid V396 Cyg (P = 33.3 days) from the plates of the Harvard Observatory and the Sternberg Astronomical Institute (SAI). Combined with published photoelectric observations, these data were used to plot an O-C diagram covering a time interval of 108 years. The O-C diagram is parabolic in shape, enabling the first determination of quadratic light elements and calculation of the evolutionary rate of decrease of the period, dP/dt = 14.1(±0.8) s per year (log(Ṗ/P) = −6.35), in agreement with theoretical computations for the second crossing of the instability strip. The available data, reduced using the method introduced by Eddington and Plakidis, demonstrate the presence of small random period fluctuations that do not distort the evolutionary changes of the O-C residuals.
Starting Page	843
Ending Page	849
Page Count	7
File Format	PDF
ISSN	10637729
Journal	Astronomy Reports
Volume Number	56
Issue Number	11
e-ISSN	15626881
Language	English
Publisher	SP MAIK Nauka/Interperiodica
Publisher Date	2012-11-07
Publisher Place	Dordrecht
Access Restriction	One Nation One Subscription (ONOS)
Subject Keyword	Astronomy, Observations and Techniques
Content Type	Text
Resource Type	Article
Subject	Astronomy and Astrophysics Space and Planetary Science

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A search for evolutionary period variations of Cepheids using the Harvard plates: V396 Cyg