Development of spatially resolved high resolution x-ray spectroscopy for fusion and light-source research
2014
One dimensional spatially resolved high resolution x-ray spectroscopy with spherically bent crystals and 2D pixelated
detectors is an established technique on magnetic confinement fusion (MCF) experiments world wide for Doppler
measurements of spatial profiles of plasma ion temperature and flow velocity. This technique is being further developed
for diagnosis of High Energy Density Physics (HEDP) plasmas at laser-plasma facilities and synchrotron/x-ray free
electron laser (XFEL) facilities. Useful spatial resolution (micron scale) of such small-scale plasma sources requires
magnification, because of the finite pixel size of x-ray CCD detectors (13.5 μm). A von-Hamos like spectrometer using
spherical crystals is capable of magnification, as well as uniform sagittal focusing across the full x-ray spectrum, and is
being tested in laboratory experiments using a tungsten-target microfocus (5-10 μm) x-ray tube and 13-μm pixel x-ray
CCD. A spatial resolution better than 10 μm has been demonstrated. Good spectral resolution is indicated by small
differences (0.02 – 0.1 eV) of measured line widths with best available published natural line widths. Progress and status
of HEDP measurements and the physics basis for these diagnostics are presented. A new type of x-ray crystal
spectrometer with a convex spherically bent crystal is also reported. The status of testing of a 2D imaging microscope
using matched pairs of spherical crystals with x rays will also be presented. The use of computational x-ray optics codes
in development of these instrumental concepts is addressed.
Keywords:
- Correction
- Source
- Cite
- Save
- Machine Reading By IdeaReader
21
References
1
Citations
NaN
KQI