Study of the Interstellar Medium and Star Formation of a complete sample of 760 isolated galaxies

Abstract

A key problem in astronomy involves the role of the environment in the formation and evolution of galaxies. In order to answer this question it is necessary to characterize a reference sample with minimum influence from the environment, so that its evolution is completeley determined by nature. The aim of this project is to provide such reference, quantifying the ISM properties of a well defined and statistically significant sample of 760 isolated galaxies. Based on optical, Halpha and infrared luminosities, radiocontinuum emission, molecular and atomic gas content, compiled from the bibliography or observed by ourselves, together with POSS-II digitized images, we will perform a statistical study of the Interstellar Medium (ISM) properties as a function of isolation, and its relation to star formation, morphology and luminosities, as well as nuclear activity frequency. This sample will be different from previous studies by three essential characteristics: a) strict definition of isolation, b) statistical significance, and c) complete multiwavelength information concerning the ISM. It will serve to evaluate the properties of interacting galaxies, which will be of special interest to analyse the large amount of data that will be generated during the next decade for high z galaxies, with the new instruments to come. Once the analysis will be finished, the data will become public by means of a database with free internet acces via a simple and efficient WEB interface.