Water maser variability over 20 years in a large sample of star-forming regions: the complete database

TL;DR

This paper presents a comprehensive 20-year database of water maser variability in star-forming regions, providing valuable data for future studies on maser behavior and variability patterns.

Contribution

It offers the first extensive, accessible database of long-term water maser observations across a large, representative sample of star-forming regions.

Findings

Database includes detailed spectra and light curves for 43 sources.

Provides insights into variability patterns over two decades.

Accessible online for further research.

Abstract

Context. Water vapor emission at 22 GHz from masers associated with star-forming regions is highly variable. Aims. We present a database of up to 20 years of monitoring of a sample of 43 masers within star-forming regions. The sample covers a large range of luminosities of the associated IRAS source and is representative of the entire population of H2O masers of this type. The database forms a good starting point for any further study of H2O maser variability. Methods. The observations were obtained with the Medicina 32-m radiotelescope, at a rate of 4-5 observations per year. Results. To provide a database that can be easily accessed through the web, we give for each source: plots of the calibrated spectra, the velocity-time-flux density plot, the light curve of the integrated flux, the lower and upper envelopes of the maser emission, the mean spectrum, and the rate of the maser occurrence as a function of velocity. Figures for just one source are given in the text for representative purposes. Figures for all the sources are given in electronic form in the on-line appendix. A discussion of the main properties of the H2O variability in our sample will be presented in a forthcoming paper.