Fluence determination by scattering method

We present a method for fluence determination alternative to the activation one. In this new method fluence is obtained by measuring the elastic scattering produced by a thin target placed upstream of the sample. Experimental results with a 27 MeV proton beam are reported and compared with Monte-Carlo simulations. The obtained results encourage the use of the scattering method whenever it is possible. This technique overcomes the disadvantages of the activation method: -) it does not oblige the operator to handle hot activated samples, -) once calibrated, it allows online measurements of the fluence, -) it allows the stability of the beam to be monitored continuously, and -) because of the high diffusion rate the fluence measurements can maintain the precision of the calibration measurements also in the low fluence range