Astrophysics and Space Science

, Volume 133, Issue 1, pp 71–79 | Cite as

A new period and period changes in VZ Hydrae

  • R. K. Srivastava


A new period (P=2 . d 9042997) of the eclipsing binary system VZ Hydrae has been given, which is based on all the available times of minima. The period based on the photoelectric epochs has also been presented. The O−C diagram and detailed period study of VZ Hya have been presented for the first time, and the period changes have been estimated in different portions of the O−C diagram. Significant period changes do not appear to have occurred in VZ Hya, however, the O−C diagram suggests that the period of the system shows a slow tendency to increase. Period changes of 10−5 d (?) to 10−7 d have occurred around the years 1933, 1971, and 1975. All four period changes are noted in the time-interval 1918 to 1978. Upward treands appear stronger than the declining trends. Secondary minima show larger fluctuations than the primary minima. The fluctuations of the O−C values around the zero-line of VZ Hya demands notice for searching out the cause of period variations such as the presence of a third body.


Binary System Period Variation Significant Period Large Fluctuation Period Change 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© D. Reidel Publishing Company 1987

Authors and Affiliations

  • R. K. Srivastava
    • 1
  1. 1.Uttar Pradesh State ObservatoryNaini TalIndia

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