The first experimental observation of the He mass exchange between cable space and central channel in CICC obtained by SHF method during Quell

The Super High Frequency (SHF) reflecting interferometer was used first during QUELL1 to analyze properties of helium in the cooling channel of CICC during heat disturbance action. The method is based on the dependence of the phase shift of a microwave, propagating thorough the central channel of CICC on the helium permeability that is proportionally to helium density. Using a pulsed heater, dynamic processes were detected including the quick expulsion of helium from the cable space to central channel just after heat pulse. he scheme and method of measurement are given. The results of numerical simulation are presented. (author)