The conditions of gamma -ray emission by electrons interacting with the wall in medium energy electron storage rings

The condition of gamma -ray emission is reported on medium energy electron storage rings. The electrons interact with the wall during injection and after being scattered by residual gas molecules or by a mutual Coulomb interaction while circulating in the ring. It is shown that the location where the heavy interaction occurs can be determined from the injection condition and the design condition of the electron orbit. The angle at which the electrons impinge on the wall is usually about 1 degrees or less to the surface. the gamma -ray emitted one to the side of the building walls in this case can be effectively shielded by the material located along the beam ducts. An important is that, for shallow impinging electrons, convergent gamma -ray emission occurs in the backscattering direction of the electrons. By installing additional shielding materials for this convergent emission, the thickness of building shielding walls can be effectively alleviated.<>