Special Relativity sets tight constraints on the form of the possible relations between the four-momentum of a particle and the wave four-vector. In fact, we de
Ultrasonic testing is a very important non-destructive method for testing components for safety of nuclear power plants and other security and delicate parts in
PKU-FEL based on superconducting (SC) accelerator facility is under construction at PekingUniversity. It will run in IR (5 - 10 μm) and THz (100 - 3000 μm) re