BEHAVIOUR OF ELECTRON CYCLOTRON EMISSION DURING HEATING AT OMEGA > OMEGA-LH IN THE FRASCATI TOKAMAK (FT)
During the Lower Hybrid Heating experiment on FT extensive measurements have been performed at 1 < omega/omega-LH < 3 in order to study the coupling of the launched waves to plasma electrons. Very efficient tail creation and consequent bulk heating have been obtained below a critical density. Confinement and stability properties of the tails have been investigated employing three main diagnostics: electron cyclotron emission (ECE), soft x-rays, and UHF wave detection. ECE was measured by means of a Michelson interferometer giving a radiation spectrum from 50 to 900 GHz every 15 msec., and of a Fabry-Perot filter tuned at the IV harmonic. The Michelson is also sensitive to radiation at the electron plasma frequency omega-pe. Soft x-rays were detected by a surface barrier diode array, sensitive to energies between 5 and 20 keV. The UHF antenna monitored a 700 to 1200 MHz frequency band, including the ion plasma frequency omega-pi. Very long confinement times (> 100 msec) have been found for electrons with high parallel momentum, in agreement with previous results on electron heating. A strong repetitive tail instability has been found at low values of omega-pe/omega-ce.
Bibliographic Reference: 11TH EUROPEAN CONFERENCE ON CONTROLLED FUSION AND PLASMA PHYSICS, AACHEN (GERMANY), SEPT. 5-9, 1983 IN ENEA REPORT 83.23/CC, PP. 17-20, 1983 WRITE TO ENEA + CENTRO RICERCHE ENERGIA FRASCATI, SERVIZIO STUDI E DOCUMENTAZIONE, C.P. 65 00044 FRASCATI, ROMA (I
Record Number: 1989122050700 / Last updated on: 1987-01-01
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