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arXiv · 1306.1864

An independent constraint on the secular rate of variation of the gravitational constant from pulsating white dwarfs

Alejandro H. Córsico·Leandro G. Althaus·Enrique García-Berro·Alejandra D. Romero
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Abstract

A secular variation of the gravitational constant modifies the structure and evolutionary time scales of white dwarfs. Using an state-of-the-art stellar evolutionary code and an up-to-date pulsational code we compute the effects of a secularly varying $G$ on the pulsational properties of variable white dwarfs. Comparing the the theoretical results obtained taking into account the effects of a running $G$ with the observed periods and measured rates of change of the periods of two well studied pulsating white dwarfs, G117--B15A and R548, we place constraints on the rate of variation of Newton's constant. We derive an upper bound $\dot G/G\sim -1.8\times 10^{-10}$ yr$^{-1}$ using the variable white dwarf G117--B15A, and $\dot G/G\sim -1.3\times 10^{-10}$ yr$^{-1}$ using R548. Although these upper limits are currently less restrictive than those obtained using other techniques, they can be improved in a future measuring the rate of change of the period of massive white dwarfs.

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Alejandro H. Córsico, Leandro G. Althaus, Enrique García-Berro, Alejandra D. Romero. 2013-06-08. An independent constraint on the secular rate of variation of the gravitational constant from pulsating white dwarfs. https://doi.org/10.1088/1475-7516%2F2013%2F06%2F032

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