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This letter presents detailed multiband observations utilizing both ground and space based observatories. We covered far-ultraviolet (UV) to near-infrared (NIR) wavelengths, including near-ultraviolet and optical regimes as well, obtaining both photometry and spectroscopy data in detail.

We made use of many world class international facilities extensively to obtain data. We tried to understand the early phase evolution (up to 20 days after 💥) in detail utilizing this rich data set. We estimated various parameters including explosion energy, circumstellar mass and its distribution, and presented a detailed qualitative analysis of UV spectra.

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(CoralAI Summary): The paper presents a study on the Type IIP supernova SN 2018gj, focusing on its photometric and spectroscopic properties. The supernova exhibited a shorter plateau phase of about 70 days compared to the typical 100-day plateau for Type IIP SNe. The study includes UV, optical, and near-IR photometric observations and low-resolution optical spectroscopy from the photospheric to the nebular phase. The analysis involves the estimation of various parameters, including the plateau length, V-band peak absolute magnitude, distance estimation, and the amount of radioactive Nickel (56-Ni) produced in the explosion. It explores the spectral evolution, with a notable observation of persistent blueshift in emission lines until the late nebular phase, a feature uncommon in Type IIP SNe. The study utilized semianalytical modeling to estimate the ejecta mass, progenitor radius, total energy, and synthesized 56-Ni mass. The study discusses the implications of consistent blueshifted emission lines and the absence of CSM interaction evidence in the spectra. The lack of dust signatures in the ejecta, along with the possibility of intrinsic high velocity of the progenitor star, are also considered. Overall, the research provides a detailed investigation of SN 2018gj, offering insights into its unique properties, supernova evolution, and potential progenitor characteristics through a combination of observational data, modelling, and analysis.

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(CoralAI Summary): The article presents detailed observations and analyses of the core-collapse supernova SN 2021wvw, characterized as a rare short-plateau Type IIP supernova. It reports multiband photometric evolution for up to 250 days and spectroscopic coverage for 100 days post-explosion. SN 2021wvw exhibits an intermediate luminosity with a notably short plateau phase of approximately 75 days, followed by a sharp transition to the tail phase. The peak absolute magnitude is noted at -16.1 mag in the r-band, with a nickel mass estimated at 0.020 ± 0.006 M☉. Hydrodynamical modeling suggests a low-metallicity, high-mass red supergiant progenitor. This event highlights the diversity among transitional supernovae, bridging the gap between typical Type IIP supernovae and stripped-envelope events.