Analysis of the W 44 Supernova Remnant and its surroundings with Fermi-LAT and MAGIC

The well-known supernova remnant (SNR) W 44 is observed in high-energy gamma rays and widely studied to investigate cosmic ray (CR) acceleration. Several analyses of the W 44 surroundings showed the presence of gamma-ray emission offset from the radio SNR shell. This emission is thought to originate from escaped high-energy CRs. We present a detailed analysis of the W 44 region as seen by Fermi-LAT, focusing on the spatial and spectral characteristics of bothW44 SNR and its surroundings. The spatial analysis was limited to energies above 1 GeV in order to exploit the improved angular resolution of the instrument, deriving a detailed description of the region morphology. Observations of the north-western region of W 44, also known as SRC-1 from previous works, were conducted with the MAGIC telescopes in the very high-energy gamma-ray band. We analysed MAGIC data exploiting the spatial information derived with the Fermi-LAT analysis at GeV energies. Here we show the results of both analyses and the combined Fermi-LAT and MAGIC spectra, thus obtaining constraining information on the diffusion of the escaped CRs.