Application of a Si-diode detector for fusion product measurements in ASDEX Upgrade
The efficient confinement of the energetic charged fusion products and the complete transfer of their kinetic energy to the plasma is of great importance for the realization of a fusion reactor which will depend on alpha-particle heating. In todays fusion experiments with deuterium plasmas, this aspect can be investigated using the 1 MeV tritons from the d(d,p)t reaction. The slowing down behaviour of these tritons can be studied by measuring the 14 MeV neutrons from the t(d,alpha)n reaction (triton burnup). At ASDEX Upgrade a time-resolved diagnostic based on a silicon barrier detector has been installed to measure the time evolution of the 14 MeV neutron rate. Using the Si(n,p)Al and Si(n,alpha)Mg reactions the high energy neutrons, with an energy above the 6 MeV threshold, are converted to charged particles directly inside the semiconductor diode. The complete functionality of the detector system is demonstrated by the successful measurement of the complex spectrum of the charged reaction products in silicon triggered by fusion neutrons during plasma discharges. As an integral component of this diagnostic a time dependent burnup code based on classical slowing-down theory has been developed for the use at ASDEX Upgrade to analyse the complex time evolution of the 14 MeV neutron rate.
Bibliographic Reference: Article: Review of Scientific Instruments, Vol. 68 (1997) No. 12, pp. 4434-4438
Record Number: 199810327 / Last updated on: 1998-03-09
Original language: en
Available languages: en