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Reanalysis of Ichinohe's Observations of RU Cam

Taichi Kato·Seiichi Sakuma
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Abstract

The W Vir-type variable star, RU Cam, once claimed to have stopped pulsation, has been known to show irregularly variable amplitude. It has also shown from the analysis of the VSOLJ archive that visual observers of the VSOLJ have recorded the cessation of pulsation and its possible resumption, together with the phase of large-amplitude variation around 1910. We present the result of reanalysis of Ichinohe's original data until 1911, by using the Hipparcos V-magnitudes of the comparison stars. The range of light variation was 8.26-9.33, giving an amplitude of 1.07 mag. Our new analysis, however, rather disproves the existence of the secondary maximum which Ichinohe (1909) described, giving a more consistent, typical W Vir-type, light curve with those of other observers at that epoch.

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Taichi Kato, Seiichi Sakuma. 2001-12-12. Reanalysis of Ichinohe's Observations of RU Cam. https://arxiv.org/abs/astro-ph/0112271

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