| Abstract: | A spherical compact matched load, for high vacuum operation suited for short pulses (2 MW, 0.1 s) precise measurement has
been designed to test high power gyrotrons Bruschi, Gandini, Muzzini, Spinicchia, Cirant, Gittini, Granucci, Mellera, Nardone,
Simonetto, and Sozzi (Fusion Eng. Des. 56–57:649–654, 2001); Bruschi, Cirant, Gandini, Granucci, Mellera, Muzzini, Nardone,
Simonetto, Sozzi, and Spinicchia (Nucl. Fusion 43:1513–1519, 2003); Bruschi, Cirant, Gandini, Gittini, Granucci, Mellera,
Muzzini, Nardone, Simonetto, Sozzi, Spinicchia, Angella, and Signorelli (Development of CW and short-pulse calorimetric loads
for high power millimeter-wave Beams, 23rd Symposium on Fusion Technology, September 20–24, 2004, Venice, Italy). In order
to enhance the power handling capability of the load and to reduce the operation problems that may arise from an excessive
reflection from the load, a ray tracing code has been written to model the power distribution on the inner surface and the
pattern of the reflected radiation. The outcome of this code has been used to select a more convenient profile for the spreading
mirror of the load and to optimize a pre-load specially conceived to minimize the power reflected fraction. |
