The environment of the strongest galactic methanol maser

Abstract

The high-mass star-forming site G009.62+00.20E hosts the 6.7 GHz methanol maser source with the greatest flux density in the Galaxy which has been flaring periodically over the last ten years. We performed high-resolution astrometric measurements of the CH3OH, H2O, and OH maser emission and 7 mm continuum in the region. The radio continuum emission was resolved in two sources separated by 1300 AU. The CH3OH maser cloudlets are distributed along two north-south ridges of emission to the east and west of the strongest radio continuum component. This component likely pinpoints a massive young stellar object which heats up its dusty envelope, providing a constant IR pumping for the Class II CH3OH maser transitions. We suggest that the periodic maser activity may be accounted for by an independent, pulsating, IR radiation field provided by a bloated protostar in the vicinity of the brightest masers. We also report about the discovery of an elliptical distribution of CH3OH maser emission in the region of periodic variability.

12 pages, 3 figures, 2 tables, typos added, accepted by The Astrophysical Journal Letters

References in corpus (2)

• DiFX: A software correlator for very long baseline interferometry using multi-processor computing environments
• On the Class II Methanol Maser Periodic Variability due to the Rotating Spiral Shocks in the Gaps of Disks Around Young Binary Stars

Cited by in corpus (9)

• A global view on star formation: The GLOSTAR Galactic Plane Survey. I. Overview and first results for the Galactic longitude range 28° < l < 36°
• A 6.7 GHz Methanol Maser Survey II. Low Galactic Latitudes
• A Global View on Star Formation: The GLOSTAR Galactic Plane Survey V. 6.7 GHz Methanol Maser Catalogue
• A 6.7 GHz Methanol Maser Survey at High Galactic Latitudes
• Periodic variability of the mainline hydroxyl masers in G9.62+0.20E
• Orientation effect on the ligh curve shape of periodic methanol maser sources
• Maser Flares Driven by Variations in Pumping and Background Radiation
• Periodic 6.7 GHz $\mathrm{C}{\mathrm{H}}_3\mathrm{OH}$ maser emission in G353.273+0.641: First candidate for a pulsating high-mass protostar
• A Unified Maxwell-Bloch Framework for Multi-periodic 6.7 GHz Methanol Flaring in G9.62+0.20E