Effects of temperature variation on PLS Linac SLED-type pulse compressor system

PLS Linac, eleven SLED-type pulse compressors has been operated since 1994. SLED is one of rf pulse compressors, which consists of two high Q-value resonant cavities, 3 dB hybrid coupler and the auxiliary devices such as tuning mechanism and cooling structure. The maximum energy multiplication, klystron pulse width, rf pulse compressor input pulse width, output pulse width and cavity filling time of the SLED-type pulse compressor are 1.676, 4.0 μs, 3.17 μs, 0.83 μs and 1.99 μs respectively. The resonant frequency in the cavities should be tuned by tuning needle with maintaining a temperature compensated structural dimensions. The temperature sensitivity was about 50 KHz/°C. To hold the cavity tuning angle within ±5°, the cavity temperature has to be stable to ±0.15°C. In this paper, we describe the effect of temperature stabilization of cavities on the rf output waveform, phase and energy gain.