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arXiv · 2203.10859

Detection of periodic flares in 6.7 GHz methanol masers G45.804-0.356 and G49.043-1.079

Mateusz Olech·Michał Durjasz·Marian Szymczak·Anna Bartkiewicz
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Abstract

Context: Periodicity in 6.7 GHz methanol maser sources is a rare phenomenon that was discovered during long-term monitoring programmes. Understanding the underlying processes that lead to periodic variability might provide insights into the physical processes in high-mass star-forming regions. Aims: We aim to identify and describe new periodic methanol masers. Methods: The observations were obtained with the Torun 32m antenna. Time series analysis was conducted using well-proven statistical methods. Additionally, NEOWISE data were used to search for a correlation between infrared and maser fluxes. Results: We found two new periodic sources, G45.804-0.356 and G49.043-1.079, with periods of 416.9 and 469.3 days, respectively. For G49.043-1.079, infrared variability is simultaneous with methanol flares. Conclusions: A most likely cause of the periodicity in G49.043-1.079 is modulated accretion. For G45.804-0.356, the periodicity cannot be explained with the available data, and further research is needed.

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Mateusz Olech, Michał Durjasz, Marian Szymczak, Anna Bartkiewicz. 2022-03-21. Detection of periodic flares in 6.7 GHz methanol masers G45.804-0.356 and G49.043-1.079. https://doi.org/10.1051/0004-6361%2F202243108

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