A unified Maxwell–Bloch framework for multiperiodic 6.7 GHz methanol flaring in G9.62 + 0.20E

ABSTRACT We analyse a decade of 6.7 GHz methanol monitoring data in G9.62 + 0.20E, confirming the known periodicities of $p_{1} = 241.3 \pm 2.3$ d and $p_{2} = 52.5 \pm 0.3$ d, and identifying three new cycles at $p_{3} = 127.0 \pm 1.6$ d, $p_{4} = 163.9 \pm 2.9$ d, and $p_{5} = 204.1 \pm 1.5$ d. The 241.3-d and 204.1-d periods occur in multiple velocity channels, while the others are confined to single components. Despite their diverse morphologies and time-scales, all flares can be reproduced within a unified Maxwell–Bloch framework operating in the fast-transient superradiance regime, driven by narrow periodic pump excitations. Model fits yield consistent environmental parameters across periodicities (temperatures, collisional time-scales), pointing to broadly uniform physical conditions in the masing region. The discovery of new periodicities and their unified Maxwell–Bloch modelling provide a consistent picture of multiperiodic flaring in G9.62 + 0.20E and support superradiance as a general framework for flaring in maser-hosting regions.