Design Of A Liquid-Hydrogen Target System

An internal liquid hydrogen target is described for use with intermediate energy light ion beams. As a result, certain safety features are required to prevent a possible hydrogen explosion within the beamline or cyclotron. These safety features include an acoustical delay line which slows the hydrogen gas shock wave and a fast closing valve which shuts before any large volume of escaping gas reaches it. Other safety devices which reduce the chances of cell breakage and quickly shut off various ignition sources are discussed. Also described is a device involving a variable heat load which is coupled directly to the cryocondenser and is used to continually monitor and stabilize the pressure and temperature of the liquid hydrogen.