Model for Synchrotron Emission from Shell Supernova Remnants in Nonuniform Interstellar Medium and Nonuniform Magnetic Field

Possibility to model the high energy synchrotron emission (in X- and gamma-rays) from supernova remnants is an important task for modern astronomy and astrophysics, because it may be responsible for the nonthermal X-rays and TeV gamma-rays observed recently from a number of SNRs. This emission allows as to look in the processes of particle acceleration on SNR shocks and generation of cosmic rays. In this paper, a model for the synchrotron emission from shell SNR in nonuniform interstellar medium and nonuniform magnetic field is presented. This model is a generalization of the model of Reynolds and Chevalier developed for a spherical SNR in the uniform medium and uniform magnetic field. The model will be used for studies on the thermal and nonthermal X-ray images and spectra from nonspherical SNRs in different interstellar magnetic field configurations.