Speaker
Dr
Martin Griswold
(Tri Alpha Energy)
Description
The C-2U experiment at Tri Alpha Energy can sustain advanced beam-driven field- reversed configuration (FRC) plasmas for 5+ ms. An end loss analyzer system was developed to study thermal transport on the open field lines that surround the FRC core and connect it to the divertors through magnetic end plugs. The system is mounted directly to the divertor electrode and consists of gridded retarding-potential analyzers that measure ion current and ion energy as well as pyroelectric crystal bolometers that measure the total power flux. This combination enables calculation of the energy lost per escaping electron/ion pair. Special care was taken in the physical and electronic construction of the analyzer elements so that they could be mounted to the divertor electrode. A laser-drilled stainless steel attenuation plate at the entrance to the gridded retarding-potential analyzer reduces neutral gas load and plasma density by a factor of 60 to prevent collisions and space charge limitations inside the device. In addition, all of the electronics for the measurement are isolated from ground so that they can float to the bias potential of the electrode (up to 1kV below ground). Measurements from the analyzer system will be presented.
Primary author
Dr
Martin Griswold
(Tri Alpha Energy)
Co-authors
Dr
M. C. Thompson
(Tri Alpha Energy)
Dr
Sergey Korepanov
(Tri Alpha Energy)
