| Abstract: Core-collapse supernovae (CCSNe) exhibit a wide diversity in their photometric and spectroscopic behaviour, reflecting differences in progenitor structure, circumstellar interaction, and metallicity. Understanding the physical drivers of this diversity is essential for constraining massive-star evolution and explosion mechanisms. In this work, I present the results of a detailed study of two transitional Type II SNe—SN 2020aze and SN 2020jfo—that do not fit within the conventional IIP–IIL classification scheme. SN 2020jfo displays a short plateau (~67 days) yet retains the observational characteristics of a typical Type IIP event, whereas SN 2020aze shows an extended (~140 days) but more rapidly declining plateau, early flash ionisation features, and a shallow P-Cygni absorption indicative of a Type IIL SN. To explore the underlying progenitor differences, I estimated metallicities for a sample of short- and long-plateau SNe using Fe-line equivalent widths as a diagnostic of progenitor chemical composition. Additionally, I introduce a fully automated Python-based photometric pipeline developed for the International Liquid Mirror Telescope (ILMT), which performs point-source extraction, aperture photometry, zero-point calibration with Pan-STARRS/SDSS catalogs, and generates calibrated light curves for supernovae and other transients. This integrated study advances our understanding of the continuum between Type IIP and IIL SNe while enabling efficient transient characterization with the ILMT. |
