Modelling high-resolution spatially-resolved Supernova Remnant spectra with the Sardinia Radio Telescope

TL;DR

This paper models high-resolution, spatially-resolved spectra of Supernova Remnants using Sardinia Radio Telescope data across multiple frequencies to better understand cosmic ray acceleration and differentiate leptonic and hadronic emission contributions.

Contribution

It introduces a method for detailed, region-specific modeling of SNR spectra using multi-frequency radio observations to improve constraints on cosmic ray emission mechanisms.

Findings

Spatially-resolved radio spectra enable better modeling of SNR regions.

Radio spectral parameters are crucial for constraining gamma-ray emission components.

The approach improves understanding of cosmic ray acceleration in SNRs.

Abstract

Supernova Remnants (SNRs) exhibit spectra featured by synchrotron radio emission arising from the relativistic electrons, and high-energy emission from both leptonic (Bremsstrahlung and Inverse Compton) and hadronic processes (${\pi}^0$ mesons decay) which are a direct signature of cosmic rays acceleration. Thanks to radio single-dish imaging observations obtained in three frequency bands (1.6, 7, 22 GHz) with the Sardinia Radio Telescope (www.srt.inaf.it), we can model different SNR regions separately. Indeed, in order to disentangle interesting and peculiar hadron contributions in the high-energy spectra (gamma-ray band) and better constrain SNRs as cosmic rays emitters, it is crucial to fully constrain lepton contributions first through radio-observed parameters. In particular, the Bremsstrahlung and Inverse Compton bumps observed in gamma-rays are bounded to synchrotron spectral slope and cut-off in the radio domain. Since these parameters vary for different SNR regions and electron populations, spatially-resolved radio spectra are then required for accurate multi-wavelength modelling.