Investigating high-mass star formation through maser surveys

TL;DR

This paper reviews the role of interstellar maser surveys in understanding high-mass star formation, emphasizing the importance of systematic searches to determine maser evolutionary sequences and their relation to star formation stages.

Contribution

It highlights the need for large-scale maser surveys to better understand their evolutionary phases and spatial relationships with other star formation tracers.

Findings

Methanol masers may trace an earlier star formation phase.

Systematic surveys are essential for establishing maser evolutionary sequences.

Limited detailed studies of maser regions highlight the need for broader surveys.

Abstract

Interstellar masers are unique probes of the environments in which they arise. In studies of high-mass star formation their primary function has been as signposts of these regions and they have been used as probes of the kinematics and physical conditions in only a few sources. With a few notable exceptions, we know relatively little about the evolutionary phase the different maser species trace, nor their location with respect to other star formation tracers. While detailed studies of a small number of maser regions can reveal much about them, other information can only be obtained through large, systematic searches. In particular, such surveys are vital in efforts to determine an evolutionary sequence for the common maser species, and there is growing evidence that methanol masers may trace an earlier phase than the other common maser species of OH and water.