Executive Summary : | The explosive death of a star as a supernova is one of the most dramatic events in the Universe. They play important role in many areas of astrophysics. In recent years modern telescopes, with wide field of view and high cadence, are discovering a large number of these sources. Detailed studies of which improved our understanding and to some extent stellar evolution, however, there are many unsolved issues about their progenitor ans explosion mechanism. Supernovae result from either of the two mechanisms, thermonuclear explosion of white dwarf (WD) close to Chandrasekhar mass limit (Type Ia SNe) or due to core collapse of massive stars (CCSNe). SNe Ia are used as an important tool for measuring cosmological distance which led to the discovery of accelerating Universe and dark energy. There are observational evidence that SNe Ia are explosion of WD in a binary system, however, so far there is no firm detection of the progenitor. Within SNe Ia class, diversity is noticed, making identification of outliers necessary to constrain the cosmological parameters better. In order to explain the observed properties, various explosion mechanisms have been proposed. The CCSNe form a heterogeneous class with a large range of observed photometric and spectroscopic properties which led to their further sub-classification. The IIP and IIL SNe retain thick hydrogen envelope at the time of explosion, while in type IIb, Ib, Ic and broad line-Ic, also known as stripped envelope CCSNe (SE CCSNe), the outer hydrogen/helium envelope is stripped off to various degrees. The early photometry and spectroscopy provides powerful constraints on the nature of the progenitor, explosion parameters and mass-loss history of the progenitor. The SE CCSNe, supposed to be arising from very massive stars are rare. Availability of densely sampled time series photometry and spectral sequence of stripped envelope supernovae, will help in understanding how and when the outer envelope of the progenitor stars are removed before explosion. This will also help in answering a crucial question that whether the various sub-classes are distinct or they form a continuous sequence. Very late time observations of these objects have potential to probe inner regions of the explosion. Asymmetry in emission line profiles during late phase has been linked to aspherical explosions and large-scale clumping in SN ejecta. In a handful of CCSNe, progenitor is detected in the pre-explosion image. The light curve and spectral evolution of SNe provides important explosion parameters and diagnostics, which are directly related to their progenitor and explosion mechanism. Through this project we propose to infer properties of the progenitor and explosion mechanism of these SNe with the help of their observed properties. A detailed study of SNe in the nearby Universe will be helpful in understanding these events at higher red-shift. |