[The photon-stationary-field therapy with the 42 MeV betatron using wedge filters]

The dose distribution in photon beams from a 42 MeV betatron using wedge filters of lead with different angles of slope is described. The wedge coefficient to be considered at a field size of 10 X 10 cm is given. The scope for isodoses modified by wedge filters is discussed with regard to stationary-field photon therapy.