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Periodic variations in the colours of the classical T Tauri star RW Aur A

P. P. Petrov·J. Pelt·I. Tuominen
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Abstract

The classical T Tauri star RW Aur A is an irregular variable with a large amplitude in all photometric bands. In an extended series of photometric data we found small-amplitude periodic variations in the blue colours of the star, with a period of 2.64 days. The period was relatively stable over several years. The amplitude of the periodic signal is 0.21 mag in U-V, 0.07 mag in B-V, and about 0.02 mag in V-R and V-I. No periodicity was found in the V magnitude. The relevance of this photometric period to the recently discovered periodicity in spectral features of the star is discussed, and the hypothesis of a hot spot is critically considered.

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P. P. Petrov, J. Pelt, I. Tuominen. 2001-06-25. Periodic variations in the colours of the classical T Tauri star RW Aur A. https://doi.org/10.1051/0004-6361%3A20010883

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