MONTE-CARLO CODES APPLICATIONS TO THE LOW LET RAYS IN RADIATION-THERAPY

In radiation therapy, there is low LET rays : photons of Co-60, photon s and electrons to 4 at 25 MV created in a linac, photons of Cs-137, o f Ir-192 and of I-125. To know the most exactly possible the dose to t he tissu by this rays, software and measurements are used. With the de velopment of the power and the capacity of computers, the application of Monte Carlo codes expand to the radiation therapy which have permit ted to better determine effects of rays and spectra, to explicit param eters used in dosimetric calculation, to verify algorithms, to study m easurements systems and phantoms, to calculate the dose in inaccessibl e points and to consider the utilization of new radionuclides.