Stress waves due to deposited heat in mercury and lead spallation targets

Stress waves resulting from deposited heat in mercury and lead spallation t argets were studied. A computation was carried out with the following condi tions: the incident proton energy and current are 1.5 GeV and 3.3 mn, respectively : the total proton energy is 5 MW in short pulses at a frequency of 50 Hz, targets are mercury and lead, proton beam profile has a Gaussian distribution. The following results are obtained: It is found that the cylindrical part of the container expands due to stres s waves with periods of 180 mu s for mercury and 130 mu s for lead. The per iods are roughly evaluated by D/V, where D is the diameter of target contai ner, 0.2 m,and V the speed of sound in fluid materials. Membrane components of stress control large amplitude stress waves, whilst beading stress components induce high frequency stress waves in both target s. A fitting function describing deposited energy as a function of position in the target was proposed. The ratio of deposited energy to the projectile e nergy is under 50% for 1.5 GeV protons for both targets.