Time‐resolving extreme ultraviolet spectrograph for fusion diagnostics

A time‐resolving spectrograph for the simultaneous measurement of emissions at extreme ultraviolet wavelengths (300–2200 A) is described. The spectrograph is a 400‐mm normal incidence f/30 system with seven gratings. Together two of the gratings cover the entire wavelength range at low resolution. The other five gratings have higher dispersion and cover adjacent intervals of the spectrum. The spectral resolution varies between 0.7–4 A. The detector consists of a windowless microchannel plate/phosphor screen image intensifier, coupled by fiber optics to a 1024‐element self‐scanning integrated photodiode array. The output from the array is digitized and stored by a small desktop computer which has sufficient memory to record up to 80 spectra during a single plasma discharge.

[1]  R. Richards.  Broadband stable detector for ultraviolet (300-1700 A) plasma spectroscopy. , 1978, The Review of scientific instruments.

[2]  H. Moos,et al.  Penning discharge as a photoelectric EUV spectroscopy source. , 1977, Applied optics.

[3]  R. Richards,et al.  Spatial imaging detector system for pulsed plasma extreme ultraviolet diagnostics , 1980 .

[4]  R W Simpson,et al.  Noise in large-aperture self-scanned diode arrays. , 1979, The Review of scientific instruments.

[5]  W. Hecq,et al.  Low energy neutral beam production by laser vaporization of metals , 1980 .

[6]  D. Tomboulian,et al.  Spectral and Angular Distribution of Ultraviolet Radiation from the 300-Mev Cornell Synchrotron , 1956 .

[7]  J. Terry,et al.  Construction, calibration, and application of a compact spectrophotometer for EUV (300-2500-A) plasma diagnostics. , 1979, Applied optics.

[8]  Y. Talmi,et al.  Self-scanned photodiode array: a multichannel spectrometric detector. , 1980, Applied optics.

[9]  Equipe Tfr,et al.  Tokamak plasma diagnostics , 1978 .

[10]  M. Mcdowell,et al.  Atomic and molecular processes in controlled thermonuclear fusion , 1981 .

[11]  E. Marmar,et al.  Impurity transport in a quiescent tokamak plasma , 1975 .

[12]  A. Broadfoot,et al.  Photoelectron counting with an image intensifier tube and a self-scanned photodiode array. , 1976, Applied optics.

[13]  P. Stott,et al.  Plasma-surface interactions in tokamaks , 1979 .

[14]  E. B. Saloman,et al.  Unfolding first and second order diffracted radiation when using synchrotron radiation sources: a technique. , 1975, Applied optics.

[15]  R. Bell,et al.  The molybdenum spectrum emitted by a tokamak plasma in the 300–500 Å range , 1981 .