Experimental study of conventional and multipass Thomson scattering diagnostic systems

A low-cost, simple and effective multipass structure was built and tested for the first time in a theta-pinch device, the compact torus TC-1. A detailed analysis of the gain in the scattered signal produced by the multipass system is presented. The use of a multipass geometry for Thomson scattering experiments in theta-pinch devices or in more dense plasmas as well as in plasmas with higher Zeff is recommended for increasing the relationship between scattered and bremsstrahlung signals. (author)