New synchronization method of arbitrary different radio frequencies in accelerators

In electron accelerator facilities, radio frequencies for a linac accelerator and a circular accelerator including a booster synchrotron ring and a storage ring are completely different. In order to improve the beam transmission efficiency from a linac to a circular accelerator, and to make the beam intensity constant, both rf's are generally synchronized. This method is well known and uses a common subharmonic frequency of around 10 MHz. The rf's used are generated by using a frequency multiplier from the common frequency, and they are continuously generated. We paid attention to the fact that the electron beam from a linac accelerator is always pulsed, and the rf of the linac requires only a moment during beam emission and acceleration. Taking this fact into account, we invented a new synchronization method for the rf's of both the linac and the circular accelerators. The new method is explained by describing a concrete example at the synchrotron radiation facility, SPring-8 (Super Photon ring 8 GeV). A 2856 MHz rf for the linac is generated by 508.58 MHz rf of the storage ring for a short duration of about 290 μs. Thus, the phase difference between the two rf's is automatically fixed. This method can be applied to any combination of arbitrary different rf's.