Device for the electron bunch length measurement of 1-5 mm RMS

Two variants of bunch length monitor (BLM) for the measurement of 1-5 mm RMS bunch length (/spl sigma//sub z/) are offered. The first one was designed for the measurement of a single bunch RMS. It consists of two cavities, each of them operates at two modes, E/sub 010/ and E/sub 110/. The second variant of BLM was designed for the measurement of a RMS of the bunches with repetition period less then 16 ns (series of identical bunches). There are two cavities in the BLM too. Loop coupling is used for the cavities and cavity-filters.