Supernovae and Interacting Binaries
The study of supernovae, novae and interacting binaries has always been a primary research topic at the OAPD, since its foundation and especially under the leadership of the late Leonida Rosino. Several scientists at OAPD continue these studies, using many ground-based telescopes and space observatories and sampling the whole electromagnetic spectrum. Type Ia Supernovae events are extensively studied through the interpretation of light curves and spectra to derive information on the explosion mechanism, and to interpret their diversity.
This project needs extensive monitoring of the events from the UV to the IR, and from the photospheric to the nebular phase. The question of the SNIa progenitors is addressed from two complementary points of view: the spectral properties of the event (e.g. the detection of circumstellar material), and the characterization of the distribution of the delay times of the SNIa from their rates in different contexts. We investigate Core Collapse Supernovae thoroughly, photometrically and spectroscopically. The data are modelled to derive the physical parameters of individual events, with the ultimate aim of understanding the progenitors, their evolution and their final explosions. Type Ic Supernovae are also studied, specifically for their relation to Gamma Ray Burst events. The determination of the rate of SNe of all kinds is a distinctive topic at OAPd, with the careful definition of galaxy samples and the study of selection effects. Research in this field continues, with special attention to the rates at intermediate redshfit and their interpretation in terms of the cosmic evolution of the star formation rate. The ample variety of interacting binaries is investigated through systematic, long term monitoring programs at the Asiago telescopes, as well as exploiting observations from other facilities. We study White Dwarfs in binary systems undergoing fast mass transfer as potential SNIa progenitors, especially recurrent novae. We aim at deriving the abundances in the ejecta, to reveal whether the accreted mass is completely ejected in the outburst or not. A complementary research is done on the population of these binaries in external galaxies. We study the different types and relate them to their parent stellar population. Finally we study individual classical and recurrent Novae, to determine the energetics, the velocity field of the ejecta, and to map the whole outburst evolution. Symbiotic Binaries are systematically observed to derive, among other properties, the binary orbits and physical parameters of the components.