New O-Cs for the Classical Cepheids RY Cas and V Lac over a Century (1873-2022)

Guy Boistel

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arXiv · 2407.03730

New O-Cs for the Classical Cepheids RY Cas and V Lac over a Century (1873-2022)

Guy Boistel

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Abstract

We give here new O-C diagrams of the two classical Cepheids RY Cas and V Lac, established on a large basis of times of maximum of light, which covers more than a century. These two Cepheids present a variation of their period for which it is possible to calculate an annual rate. This rate equals +1.86 s/yr for RY Cas and -0.81 s/yr for V Lac. Based on these two new O-C diagrams neither of them seems to show any association to a binary system.

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Guy Boistel. 2024-07-04. New O-Cs for the Classical Cepheids RY Cas and V Lac over a Century (1873-2022). https://arxiv.org/abs/2407.03730

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