Statistical properties of the IR emission in pairs of galaxies of mixed morphology

This is a statistical work devoted to explore the link between induced star formation and galaxy-galaxy interactions in a sample of mixed morphology (E+S) pairs from the Karachentsev Catalogue. The catalogue of isolated galaxies CIG from Karachentseva and the (S+S) pairs from the Karachentsev Catalogue are used as comparison samples. The study of the Mid and Far Infrared properties is based on (1) a new analysis and reduction of the IRAS observations for all the (E+S) and CIG galaxies by using the SCANPI/HIRES processes at IPAC to obtain major sensitivity, better quality fluxes and spatial resolution in the IRAS bands, (2) a work hipothesis; the (E+S) pairs are the only sample of binary galaxies where the effects of FIR confusion are likely to be small. This allows us to associate the FIR emission to the spiral component in cases where the resolution is low, and (3) the interpretation of the MId and Far Infrared emission properties by means of non-parametric statistical methods from the Survival Analysis. The ralationship between star formation and and galaxy interactions is established for the first time. A high fraction of physical (E+S) pairs is infered from this study, facing directly some current theories of galaxy formation.