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arXiv · 2411.09739

Caught in the Act: Observations of the Double-mode RR Lyrae V338 Boo During the Disappearance of a Pulsation Mode

Kenneth Carrell·Ronald Wilhelm·Andrew Tom·Horace Smith·Adam Popowicz·Gary Hug·Stephen M. Brincat·Fabio Salvaggio·Keith Nakonechny·Darrell Lee·Teofilo Arranz Heras·Tony Vale·Davide Mortari·Andre Steenkamp·Ralph Rogge·Jacek Checinski
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Abstract

New results on the behavior of the double-mode RR Lyrae V338 Boo are presented. The Transiting Exoplanet Survey Satellite (TESS) observed this star again in 2022, and an observing campaign of the American Association of Variable Star Observers (AAVSO) was completed after the TESS observations as a follow-up. We find that the first overtone pulsation mode in this star completely disappears during the TESS observing window. This mode reappears at the end of the TESS observations, and the AAVSO observing campaign shows that in the months that followed, the first overtone mode was not only present, but was the dominant mode of pulsation. This star, and potentially others like it, could hold the key to finally solving the mystery of the Blazhko effect in RR Lyrae.

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Kenneth Carrell, Ronald Wilhelm, Andrew Tom, Horace Smith, Adam Popowicz, Gary Hug, Stephen M. Brincat, Fabio Salvaggio, Keith Nakonechny, Darrell Lee, Teofilo Arranz Heras, Tony Vale, Davide Mortari, Andre Steenkamp, Ralph Rogge, Jacek Checinski. 2024-11-14. Caught in the Act: Observations of the Double-mode RR Lyrae V338 Boo During the Disappearance of a Pulsation Mode. https://doi.org/10.3847/1538-4357%2Fad7094

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