Dosimetry of Intense Particle Beams Using the Thermomechanical Behaviour of an Irradiated Aluminium Alloy

An hydrodynamic code coupled with a "PUFF-type" equation of state has been set up to investigate the thermomechanical behaviour of an aluminium alloy irradiated by a 1 MeV electron beam. The absorbed flux can reach 3500 J/cm2 with an exponential damping along 1 mm dep;th. A weaker flux .is produced with 1 MeV protons whose the stopping range is 10 pm for a 8000 J/g dose. Thermal stresses generated into a material irradiated by an intense 0 1 MeV particle beam, can be easily studied in the range '0 300 kb. Measurements are achieved either by piezoelectric and piezoresistive gauges (e. g. quartz, manganin, carbon) or by laser Doppler interferometry. Theoretical interpretation of thermomechanical phenomena requires the use of a monodimensional hydrodynamic code connected with an equation of state. We essentially make use of Newton law in lagrangian coordinates and "PUFF-type" equation: is a temporal variation, AX the areal mass of a sample slice, AIJ the temporal variation of particle velocity U, AP the spatial variation of pressure P, E the mass energy, D the specific mass, f(U) the compression and release func@ion of the cold material (see figure I), G ( E ) the Griineisen parameter (see figure 2). In the two following sections, examples of computations are given for an aluminium alloy target irradiated by the electron or the proton beam drifted from the generator "SIDONIX". Article published online by EDP Sciences and available at http://dx.doi.org/10.1051/jphyscol:1988729