Supernova VLBI

TL;DR

This paper reviews two decades of VLBI observations of supernovae, discusses future imaging prospects with space VLBI (VSOP-2), and highlights the potential for detailed, early-stage supernova studies with improved resolution.

Contribution

It presents a comprehensive review of supernova VLBI observations and explores the capabilities of upcoming space VLBI technology for early and detailed supernova imaging.

Findings

Approximately 50 supernovae detected at radio wavelengths.

Four supernovae imaged in detail with VLBI.

Four supernovae detectable with VSOP-2 for early-stage studies.

Abstract

We review VLBI observations of supernovae over the last quarter century and discuss the prospect of imaging future supernovae with space VLBI in the context of VSOP-2. From thousands of discovered supernovae, most of them at cosmological distances, ~50 have been detected at radio wavelengths, most of them in relatively nearby galaxies. All of the radio supernovae are Type II or Ib/c, which originate from the explosion of massive progenitor stars. Of these, 12 were observed with VLBI and four of them, SN 1979C, SN 1986J, SN 1993J, and SN 1987A, could be imaged in detail, the former three with VLBI. In addition, supernovae or young supernova remnants were discovered at radio wavelengths in highly dust-obscured galaxies, such as M82, Arp 299, and Arp 220, and some of them could also be imaged in detail. Four of the supernovae so far observed were sufficiently bright to be detectable with VSOP-2. With VSOP-2 the expansion of supernovae can be monitored and investiated with unsurpassed angular resolution, starting as early as the time of the supernova's transition from its opaque to transparent stage. Such studies can reveal, in a movie, the aftermath of a supernova explosion shortly after shock breakout.