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Observations of supernova remnants (SNRs) are a powerful tool forinvestigating the later stages of stellar evolution, the properties of theambient interstellar medium, and the physics of particle acceleration andshocks. For a fraction of SNRs, multi-wavelength coverage from radio to ultrahigh-energies has been provided, constraining their contributions to theproduction of Galactic cosmic rays. Although radio emission is the most commonidentifier of SNRs and a prime probe for refining models, high-resolutionimages at frequencies above 5 GHz are surprisingly lacking, even for bright andwell-known SNRs such as IC443 and W44. In the frameworks of the AstronomicalValidation and Early Science Program with the 64-m single-dish Sardinia RadioTelescope, we provided, for the first time, single-dish deep imaging at 7 GHzof the IC443 and W44 complexes coupled with spatially-resolved spectra in the1.5-7 GHz frequency range. Our images were obtained through on-the-fly mappingtechniques, providing antenna beam oversampling and resulting in accuratecontinuum flux density measurements. The integrated flux densities associatedwith IC443 are S_1.5GHz = 134 +/- 4 Jy and S_7GHz = 67 +/- 3 Jy. For W44, wemeasured total flux densities of S_1.5GHz = 214 +/- 6 Jy and S_7GHz = 94 +/- 4Jy. Spectral index maps provide evidence of a wide physical parameter scatteramong different SNR regions: a flat spectrum is observed from the brightest SNRregions at the shock, while steeper spectral indices (up to 0.7) are observedin fainter cooling regions, disentangling in this way different populations andspectra of radio/gamma-ray-emitting electrons in these SNRs.

Imaging of SNR IC443 and W44 with the Sardinia Radio Telescope at 1.5 GHz and 7 GHz