Neutron Spectra from Beam-Heated Fusion Plasmas

• The spectra of fusion neutrons emerging from a deuterium-beam heated deuterium or tritium plasma yield information of both the bulk plasma and of the beam slowing down. A computer code has been developed to model plasma-plasma (p-p), beam-plasma (b-p) and beam-beam (b-b) interaction for the case of a single or several co-directed beams. It is found that for a high-temperature plasma (T ⪢ 1 keV) b-b interaction is negligible due to the low associated neutron emission. p-p neutron spectra reflect the bulk ion plasma temperature and density as well as toroidal rotational velocity. b-p spectra shifts and broadenings are sensitive to beam injection geometry and deposition, beam energy, ion and electron temperature, toroidal rotation and the density of neutrals. The mixing of full energy beam neutrals with half- and third-energy components has only a slight impact on the neutron spectrum when the beam power is held constant. For a JET-like Tokamak (D → D, beam power 5 MW, beam energy 160 keV) it is further found that for T ⪡ 8 keV the b-p neutron flux dominates, whereas for T ⪢ 8 keV the p-p flux dominates.

Subject headings

NATURVETENSKAP  -- Fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences (hsv//eng)

Keyword

Fysik

Physics

Publication and Content Type

ref (subject category)

art (subject category)