Determine the location and origin of the 12.2 GHz quasi-periodic masers

Determine whether the quasi-periodic 12.2 GHz methanol maser emission in the MM2/3-dominated velocity range was triggered by the 2015 NGC 6334I-MM1 accretion event and whether the periodic masers are located in NGC 6334I-MM1, MM2, or MM3.

Background

The paper identifies quasi-periodic activity with a period of approximately 380–390 days in the 12.2 GHz methanol maser emission dominated by the MM2/3 velocity range. The activity began roughly 800 days after the 2015 accretion event in NGC 6334I-MM1, suggesting a possible causal connection, but the single-dish monitoring data do not establish the spatial location of the emitting masers.

The authors state that the relevant masers could be in MM1, MM2, or MM3 and explain that multiple epochs of interferometric observations at several maser transitions are needed both to confirm the periodic features and to identify their host source.