EXPERIMENTAL-STUDY OF A TOROIDAL MAGNETIZED PLASMA IN THE PRESENCE OFA WEAK VERTICAL MAGNETIC-FIELD

Detailed measurements of density and floating potential in the poloida l cross section of a toroidal plasma with an extended source at the mi nor axis are presented in the first half of the paper. The second part deals with the effect of k(parallel to) on curvature-induced low freq uency (< omega(i), the ion gyro frequency) fluctuations, where k(paral lel to) is the wavenumber parallel to the ambient magnetic field. The variation in k(parallel to) is introduced with the help of a weak vert ical magnetic field, which helps in varying the length of the toroidal magnetic field lines. We report a reduction in the fluctuation level in the presence of a weak vertical field.