Title: SN 1993J: The early radio emission and evidence for a changing presupernova mass-loss rate
Abstract: view Abstract Citations (135) References (25) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS SN 1993J: The Early Radio Emission and Evidence for a Changing Presupernova Mass-Loss Rate van Dyk, Schuyler D. ; Weiler, Kurt W. ; Sramek, Richard A. ; Rupen, Michael P. ; Panagia, Nino Abstract We present daily-to-weekly monitoring of the first 8 months of radio emission from supernova (SN) 1993J using the Very Large Array at five wavelengths, providing the most detailed radio light curves ever established for an SN. While the radio emission evolves regularly in both time and frequency, the usual form of the SN shock/circumstellar medium interaction model does not adequately describe the observations. In particular, for a spherically symmetric geometry, the circumstellar density profile is flatter (ρ_CSM_ is proportional to r^-1.5^) than that (ρ_CSM_ is proportional to r^-2^) generally assumed for a constant mass-loss rate, constant-velocity stellar wind. This is interpreted as a decrease in the pre-SN mass-loss rate (or increase in wind velocity) immediately prior to explosion. Additionally, the rate of increase in the early radio emission at each frequency cannot simply he described as due to decreasing external absorption by a uniform medium, but requires the presence of higher density "clumps" or "filaments" embedded in the stellar wind. Publication: The Astrophysical Journal Pub Date: September 1994 DOI: 10.1086/187525 Bibcode: 1994ApJ...432L.115V Keywords: Flux Density; Radio Emission; Shock Wave Interaction; Solar Wind Velocity; Stellar Winds; Supernovae; Light Curve; Radio Spectra; Stellar Envelopes; Very Large Array (Vla); Astronomy full text sources ADS | data products SIMBAD (2) NED (2)
Publication Year: 1994
Publication Date: 1994-09-01
Language: en
Type: article
Indexed In: ['crossref']
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Cited By Count: 146
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