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arXiv · 2608.12686

Titanium Oxide Absorption as a Proxy to Detect Long term Variation and Activity Cycle in Proxima Centauri

Fatemeh Azizi·Mohammad Taghi Mirtorabi·Rahimeh Foroughi
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Abstract

Stellar activity cycles on magnetically active stars can be estimated by molecular absorption bands. We have previously introduced a molecular index which compares absorptional line strength of the TiO567nm with its nearby continuum has previously been introduced. In this work we use this indicator to evaluation long-term activity variations for Proxima Centauri star, using spectroscopic data from HARPS. The results indicate periodicity with an activity period of 2873(+47.4-53.9) days, which is similar to the previous measurements from other indicators.

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Fatemeh Azizi, Mohammad Taghi Mirtorabi, Rahimeh Foroughi. 2026-08-13. Titanium Oxide Absorption as a Proxy to Detect Long term Variation and Activity Cycle in Proxima Centauri. https://arxiv.org/abs/2608.12686

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