Physical design of an Atmospheric Neutron Irradiation Spectrometer at China Spallation Neutron Source

•The excellent initial conditions: The neutron irradiation facility is based on a 1.6 GeV proton accelerator and the neutrons are extracted in the forward direction at an orientation of 41° to the proton beam. These ensure the atmospheric neutron spectrum with the full energy spectrum from meV to GeV, which is the highest neutron energy that matches the JEDEC spectrum so far.•The unique facility design: The most challenging design of ANIS is the beam adjustments of the high energy neutrons. It is necessary not only to collimate the beam spot, but also to expand the beam spot, to modulate the neutron flux, to adjust the energy spectrum, and also to maintain the uniformity of the beam spot, while keeping the atmospheric neutron spectrum as far as possible.•Currently, the possibility of extensive neutron radiation test for electronics is seriously hindered by the scarce availability of neutron facilities, particularly that with atmospheric-like neutron spectrum which need large and expensive accelerators. ANIS is a new powerful complement facility, which will promote neutron irradiation test and related scientific research vigorously throughout the worldwide.