The nearby face-on spiral galaxy NGC 5584, at a distance of 23 megaparsecs (75
million light years) is a member of the Virgo III group of galaxies
which are positioned to the east of the Virgo Supercluster. It has
two known associated supernova (SN): SN1996aq and SN2007af.
Zakir et al. report the ASKAP
Evolutionary Map of the Universe (EMU) survey detection of radio continuum
emission from SN1996aq, a Type Ic supernova within NGC 5584.
Analysis at multiple radio frequencies reveals
radio emission coincident with SN1996aq. A flatter radio
spectral index is found compared to the 2009 observations, indicating rapid
evolution of SN1996aq. Conversely, no radio emission is observed from
NGC 5584's other known supernova, SN2007af. Furthermore,
two other significant radio continuum regions were identified with properties
consistent with ionized HII regions.
The image above shows at left, the ASKAP-EMU radio-continuum image at 943 MHz
at the resolution of 15 arcseconds × 15 arcseconds (with this beamsize
shown in the bottom-right corner). At right is a James Webb Space Telescope
NIRCam image with radio contours overlaid.
Regions of interest are labeled and the squares
represent the location of SN1996aq and SN2007af.
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