Investigations of Alfvén Modes at the Globus-M2 Tokamak Using a V-Band Multifrequency Doppler Reflectometer
V. V. Bulanin, И. М. Балаченков, В. И. Варфоломеев, В. К. Гусев, Г. С. Курскиев, В. Б. Минаев, М. И. Патров, А. В. Петров, Yu. V. Petrov, А. М. Пономаренко, A. Yu. Telnova, П. Б. Щеголев, A. Yu. Yashin
Abstract
We present new information on the development of Alfvén modes on the Globus-M2 spherical tokamak. Data have been obtained using a V-band Doppler reflectometer with probing radiation frequencies from 50 to 75 GHz. Аs a multifrequency source of probing radiation, a microwave harmonic synthesizer has been used. As a result of using the new reflectometer, the toroidal Alfvén mode localization in a magnetic field of 0.5 T has been obtained. The spectral components of the Alfvén mode with Doppler frequency shifts caused by toroidal plasma rotation have been registered. In the central regions of the discharge, so-called “Alfvén cascades” have been investigated.