Subhash Bose

I am a researcher in astrophysics, and I also enjoy doing web development and general-purpose programming (nope, not just numerical coding :). In this website, you will find information on my research, and also various online tools and software I made, which are mainly related to astronomy.

At present, I am a postdoctoral researcher at The Ohio State University (OSU), USA, and currently, I hold CCAPP postdoctoral fellowship. Earlier, until…

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Research Highlights

An overly-luminous Type II supernova from a massive progenitor

Bose, S. et al., 2021, MNRAS, 503, 3472

ASASSN-18am/2018gk is a newly discovered member of the rare group of luminous, hydrogen-rich supernovae with a peak absolute magnitude of \(M_V \approx -20\) mag that is in between normal core-collapse SNe and superluminous SNe, which was also considered as a missing gap by some earlier studies. Only about five such supernovae have been identified so far, which also includes our previously discovered ASASSN-15nx (Bose, S. et al., 2018b, ApJ, 862, 107). The high intrinsic luminosity (without circumstellar interaction) of these supernovae makes it difficult or impossible to explain by widely accepted neutrino driven explosion mechanism. In this work, we examine various powering mechanisms, including radiative diffusion and magentar spindown models. Both of these models required a high synthesised \(\rm ^{56}Ni\) mass \(M_{\rm Ni} \sim0.3-0.4\,\rm M_\odot\)

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What's New

All purpose Astro Calculator

October 30, 2022

Online command-line calculator with various astronomy/astrophysics functions constants and unit.

Error Propagation Calculator

Online tool to analytically (and numerically) calculate error propagation relation from a given function.

Paper on ASASSN-18am

New paper on supernova ASASSN-18am/2018gk. Read highlights here or full article in ArXiv.

Object Visibility Plotter

Online tool to generate interactive visiblity plot of an object of given RA, Dec., date and site location.

SimSpec docs. added

Added documentation for SimSpec spectroscopic pipeline.

GSpread DBMS

Python module for using Google Spreadsheet as as a database.