86 GHz SiO maser survey of late-type stars in the Inner Galaxy. I. Observational data

TL;DR

This survey of 441 late-type stars in the Inner Galaxy using 86 GHz SiO maser observations identified 271 sources, significantly expanding the available data for galactic kinematic studies.

Contribution

First large-scale SiO maser survey in the Inner Galaxy providing extensive velocity data for late-type stars.

Findings

Detected SiO masers in 271 out of 441 stars.

Doubled the existing line-of-sight velocity data in the surveyed area.

Confirmed the stars' location within the Inner Galaxy.

Abstract

We present 86 GHz (v = 1, J = 2 -1) SiO maser line observations with the IRAM 30-m telescope of a sample of 441 late-type stars in the Inner Galaxy (-4 degr < l < +30 degr). These stars were selected on basis of their infrared magnitudes and colours from the ISOGAL and MSX catalogues. SiO maser emission was detected in 271 sources, and their line-of-sight velocities indicate that the stars are located in the Inner Galaxy. These new detections double the number of line-of-sight velocities available from previous SiO and OH maser observations in the area covered by our survey and are, together with other samples of e.g. OH/IR stars, useful for kinematic studies of the central parts of the Galaxy.