Automatic phase calibration for RF cavities using beam-loading signals
Precise calibration of the cavity phase signals is necessary for the operation of any particle accelerator. For many systems this requires human in the loop adjustments based on measurements of the beam parameters downstream. Some recent work has developed a scheme for the calibration of the cavity phase using beam measurements and beam-loading however this scheme is still a multi-step process that requires heavy automation or human in the loop. In this paper we analyze a new scheme that uses only RF signals reacting to beam-loading to calculate the phase of the beam relative to the cavity. This technique could be used in slow control loops to provide real-time adjustment of the cavity phase calibration without human intervention thereby increasing the stability and reliability of the accelerator.
Beam-based phase monitoring and gradient calibration of Jefferson Laboratory RF systems
Beam-based monitoring was instituted at Jefferson Lab in December of 1994 to correct the RF system phase setpoints against drifts of the master oscillator system, while running transparently to normal beam setup and delivery operations. As then implemented, the master oscillator distribution was subject to large thermal drifts, but no means existed of tracking the distribution of drifts, nor of identifying phase errors for individual cavities following maintenance activities. The background process implemented is capable of cresting each of the 312 cavities in the linacs to within approximately /spl plusmn/2 degrees. In addition, during dedicated system measurement operations, the RF cavity gradients have been calibrated with beam to within a tolerance of approximately /spl plusmn/5%. These beam-based results are in many cases more than 20% different from commissioning results using RF measurement techniques.
Handbook of Concrete Engineering
Handbook of concrete engineering , Handbook of concrete engineering , مرکز فناوری اطلاعات و اطلاع رسانی کشاورزی