Studying The Non-thermal Radiation Of The Shell-type Supernova Remnants And The Supernova Remnants-Molecular Cloud Systems

Supernova remnants?SNRs?can emit non-thermal radiation from radio to gamma-rays,and the particle energy distribution and the origin of the gamma-rays belong to the current research issues in astrophysics.We systematically studied high-energy particle distributions and non-thermal radiation properties of SNRs.Based on the one-zone mod-el for the multiband nonthermal radiation,the spectra generated by synchrotron radiation,inverse Compton scattering and p-p interaction are calculated with a certain particle dis-tribution.The parameters of the model are constrained by the Markov Chain Monte Carlo?MCMC?method.The particle distribution and radiation characteristics in the remnants are obtained by comparing with the observed fluxes.For the shell-type SNRs RX J1713.7-3946,HESS J1731-347,RX J0852.0-4622 and RCW 86,we assume that the particle distribution is a simple power-law with a high-energy cutoff.In the leptonic scenario,the non-thermal radiation from the radio to the X-ray bands originates from the synchrotron radiation of electrons,whereas the gamma-rays are produced via inverse Compton scattering process of these electrons.The spectral indexes of the electrons are between 1.7 and 2.4,and the Cutoff energies are in the range 11-45 TeV.Moreover,the magnetic field strengths are in the range of 6-24 ?G with the total energies of?3-11?×10⁴⁷ erg for the electrons.Alternatively,in the hadronic scenario,gamma-rays are produced via p-p interaction between the high-energy protons and the surrounding ones.The spectral indexes of the protons for the remnants are between 1.4 and 1.8,the Cutoff energies are in the range of 15-58 TeV,and the total energy of the protons W_p are about?6-7?×10⁴⁹ erg.For the SNRs interacting with molecular clouds IC 443,W 44,W 51C,W 49B,Kes 41 and Puppis A,the proton distributions are assumed to be a smoothed broken power-law or a broken power-law.The results show that spectral indexes for the protons are between 1.8 and 2.0 with the break energies ranging from 20 to 30 GeV.Finally,we studied the correlation between the free parameters and the age of remnants.For the shell-type SNRs,the magnetic field B,W_e,W_p are positively correlated with the age,while the Cutoff energy is inversely correlated with the age.For the SNR-MC systems,which indicates that there is no direct correlation between the parameters and the age.