TY - JOUR
T1 - Modeling of a diagnostic neutral beam for ITER
AU - Schilling, G.
AU - Synakowski, E. J.
PY - 1992
Y1 - 1992
N2 - A neutral hydrogen beam has been modeled to serve as an energetic particle source for the measurement of ion temperature profiles via charge-exchange recombination spectroscopy. Calculation of the neutral beam attenuation uses the multistep ionization cross sections of Boley, Janev, and Post. Whereas beam penetration toward the center of the discharge increases with increasing beam energy, the relevant charge-exchange cross section for the familiar C 5+ n=8-7 transition decreases above 50 keV, leading to an optimum beam energy that yields the maximum charge exchange brightness for each set of plasma conditions. This energy is in the range of 100-150 keV. As a consequence of the high plasma density, temperature, and machine size, the detected signal is dominated by visible bremsstrahlung integrated along the detector sightline, placing a premium on beam intensity, beam current density, and beam chopping with synchronous detection.
AB - A neutral hydrogen beam has been modeled to serve as an energetic particle source for the measurement of ion temperature profiles via charge-exchange recombination spectroscopy. Calculation of the neutral beam attenuation uses the multistep ionization cross sections of Boley, Janev, and Post. Whereas beam penetration toward the center of the discharge increases with increasing beam energy, the relevant charge-exchange cross section for the familiar C 5+ n=8-7 transition decreases above 50 keV, leading to an optimum beam energy that yields the maximum charge exchange brightness for each set of plasma conditions. This energy is in the range of 100-150 keV. As a consequence of the high plasma density, temperature, and machine size, the detected signal is dominated by visible bremsstrahlung integrated along the detector sightline, placing a premium on beam intensity, beam current density, and beam chopping with synchronous detection.
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U2 - 10.1063/1.1143555
DO - 10.1063/1.1143555
M3 - Article
AN - SCOPUS:0012675217
SN - 0034-6748
VL - 63
SP - 4937
EP - 4939
JO - Review of Scientific Instruments
JF - Review of Scientific Instruments
IS - 10
ER -