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arXiv · 0710.0790

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

M. Felli·J. Brand·R. Cesaroni·C. Codella·G. Comoretto·S. Di Franco·F. Massi·L. Moscadelli·R. Nesti·L. Olmi·F. Palagi·D. Panella·R. Valdettaro
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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.

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M. Felli, J. Brand, R. Cesaroni, C. Codella, G. Comoretto, S. Di Franco, F. Massi, L. Moscadelli, R. Nesti, L. Olmi, F. Palagi, D. Panella, R. Valdettaro. 2007-10-03. Water maser variability over 20 years in a large sample of star-forming regions: the complete database. https://doi.org/10.1051/0004-6361:20077804

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