Photocathode performance optimization is crucial to the operation of X-ray Free Electron Laser (FEL) facilities such as LCLS-II and the future UK XFEL as the initial photoelectron phase-space distribution directly impacts x-ray generation efficiency in the undulator. Key photocathode parameters such as transverse emittance and quantum efficiency are routinely measured to monitor and improve...
Like standard beam transformers the cryogenic current comparator (CCC) measures the intensity of particle beams via the azimuthal magnetic field. The superior performance of the CCC derives from a superconducting magnetometer (SQUID - Superconducting Quantum Interference Device), which detects fields in the fT range. This enables for current resolution in the nA range but in return needs...
Fast Beam Current Transformers (FBCTs) are essential devices for measuring bunched beam intensities in the Large Hadron Collider (LHC). A cross-calibration of these devices against DC Beam Current Transformers (DC-BCTs) is used in the LHC ring, but this method relies on assumptions that introduce inaccuracies. FBCTs are also used in the LHC transfer lines, where DC-BCTs are unavailable, making...