Pulse quality

摘要

Modulator pulse quality can be defined as achieving the best flatness for most of the top of the pulse. Top flatness within 0.1% over 3 μs has been recorded using the unique solid-state pulsed power modulator technology developed by ScandiNova Systems AB. Additionally, the flat top of the pulse does not have ripple, which is common for the traditional PFN-type of pulsed systems. For electron accelerators improved pulse quality means better defined energy and phase of the electrons. This improves the efficiency of the accelerator, reducing the number of lost electrons. If a bending or scanning magnet system is used a higher transmission of electrons will be noticed. Because of the clean top of the pulse (no ripple) the timing jitter is not as critical as before. Pulse top ripple creates a phase shift in the RF between peaks and valleys. If there is timing jitter this will move the position of these peaks and valleys relative to the RF phase, making the phase shift different from pulse to pulse and creating instabilities in the electron beam. Ripple-free and flat modulator pulses means lower beam emittance. This is very important in the scientific and research field, i.e. Free Electron Lasers (FEL) using several high power pulsed klystrons. In the medical field the pulse quality is also essential. For treatment of cancer using modern Radiotherapy technology an improved precision in delivering the right dose at the right location can be achieved. In the Industrial field efficiency and reliability is essential. For instance in the industrial X-ray or Cargo scanning field, an improved pulse quality increases the efficiency of useful radiation and thereby reduces the need of cooling and radiation shielding. This in return increases the reliability of the system.