A note on the periodic methanol masers in G9.62+0.20E

TL;DR

This paper evaluates recent models explaining periodic methanol masers in G9.62+0.20E and concludes that neither model successfully reproduces the observed light curves.

Contribution

The paper critically assesses two recent proposals for explaining periodic methanol masers and demonstrates their inability to match observed data.

Findings

Neither of the proposed mechanisms reproduces the observed light curves.

Current models are insufficient to explain the periodic methanol masers in G9.62+0.20E.

The need for alternative explanations or models is highlighted.

Abstract

A number of mechanisms to understand the periodic class II methanol masers associated with some high-mass star forming regions have been proposed in the past. Two recent proposals, ie. by Parfenov &Sobolev (2014) and Sanna et al. (2015) have been presented in order to explain the periodic masers in sources with light curves similar to the methanol masers in G9.62+0.20E. We evaluate to what extent the proposals and models presented by these authors can explain the light curve of the methanol masers in G9.62+0.20E. It is argued that neither of the proposed mechanisms can reproduce the light curves of the methanol masers in G9.62+0.20E.