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Title: Measurement and interpretation of DT neutron emission from TFTR. [TFTR (Tokamak Fusion Test Reactor)]

Miscellaneous ·
OSTI ID:7233190

A fast-ion diffusion coefficient of 0.1 [+-] 0.1 m[sup 2]s[sup [minus]1] has been deduced from the triton burnup neutron emission profile measured by a collimated array of helium-4 spectrometers. The experiment was performed with high-power deuterium discharges produced by Princeton University's Tokamak Fusion Test Reactor (TFTR). The fast ions monitored were the 1.0 MeV tritons produced from the d(d,t)p triton burnup reaction. These tritons [open quotes]burn up[close quotes] with deuterons and emit a 14 MeV neutron by the d(t,[alpha])n reaction. The measured radial profiles of DT emission were compared with the predictions of a computer transport code. The ratio of the measured-to-calculated DT yield is typically 70%. The measured DT profile width is typically 5 cm larger than predicted by the transport code. The radial 14 MeV neutron profile was measured by a radial array of helium-4 recoil neutron spectrometers installed in the TFTR Multichannel Neutron Collimator (MCNC). The spectrometers are capable of measuring the primary and secondary neutron fluxes from deuterium discharges. The response to 14 MeV neutrons of the array has been measured by cross calibrating with the MCNS ZnS detector array when the emission from TFTR is predominantly DT neutrons. The response was also checked by comparing a model of the recoil spectrum based on nuclear physics data to the observed spectrum from [sup 252]Cf, [sup 238]Pu-Be, and DT neutron sources. Extensions of this diagnostic to deuterium-tritium plasma and the implications for fusion research are discussed.

Research Organization:
Princeton Univ., NJ (United States)
OSTI ID:
7233190
Resource Relation:
Other Information: Thesis (Ph.D.)
Country of Publication:
United States
Language:
English