New methods of X-ray spectroscopy of laser-produced plasmas with one-dimensional spatial resolution

Two novel high-dispersion, high-resolution spectroscopic methods are described. The properties of the vertical dispersion variants of the double-crystal spectrometer and the Johann spectrometer with a cylindrically bent crystal are discussed and compared with those of standard spectroscopic schemes. Preliminary experimental data demonstrate the good luminosity and extreme spectral and 1-D spatial resolution of these methods, which should prove useful in high-precision X-ray spectroscopic measurements of laser-produced plasmas.

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Characterization and on-line adjustment of the sagittal-bent Laue crystal profile

Journal of Synchrotron Radiation ◽

10.1107/s1600577518008056 ◽

2018 ◽

Vol 25 (5) ◽

pp. 1346-1353

Author(s):

Weiwei Dong ◽

Quan Cai ◽

Fugui Yang ◽

Xu Liu ◽

Jiaowang Yang ◽

...

Keyword(s):

Ray Tracing ◽

Crystal Surface ◽

Great Influence ◽

High Energy ◽

Double Crystal ◽

X Ray ◽

Bent Crystal ◽

On Line ◽

Condition Adjustment ◽

Anticlastic Curvature

The sagittal-bent Laue monochromator can provide an ideal way to focus high-energy X-ray beams. However, the anticlastic curvature induced by sagittal bending has a great influence on the crystal performance. Thus, characterizing the bent-crystal shape is very important for predicting the performance of the bent-crystal monochromator. In this paper the crystal profile is measured by off-line optical metrology and on-line X-ray experiments. The off-line results showed that the bent-crystal surface could be well fitted to a saddle surface apart from a redundant cubic term which was related to the different couples applied on the crystal. On-line characterization of the meridional and the sagittal radius of the bent crystal includes double-crystal topography and ray-tracing measurement. In addition, the double-crystal topography experiment could be used as a quick diagnostic method for the bending condition adjustment. The sagittal radius of the bent crystal was characterized through a ray-tracing experiment by using a particularly designed tungsten mask. Moreover, rocking curves under different bending conditions were measured as well. The results were highly consistent with analytical results derived from the elastic theory. Furthermore, radii along different vertical positions under various bending conditions were measured and showed a quadratic relationship between the vertical positions and the meridional radii.

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Elliptically Bent Crystal Spectrometer for Z-Pinch Plasma X-Ray

Chinese Journal of Lasers ◽

10.3788/cjl20093601.0115 ◽

2009 ◽

Vol 36 (1) ◽

pp. 115-118

Author(s):

王洪建 Wang Hongjian ◽

肖沙里 Xiao Shali ◽

施军 Shi Jun ◽

黄显宾 Huang Xianbin ◽

杨礼兵 Yang Libing ◽

...

Keyword(s):

Crystal Spectrometer ◽

X Ray ◽

Pinch Plasma ◽

Bent Crystal ◽

Z Pinch

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Diagnostic potential of advanced X-ray spectroscopy for investigation of hot dense plasmas

Laser and Particle Beams ◽

10.1017/s026303460422105x ◽

2004 ◽

Vol 22 (1) ◽

pp. 25-28 ◽

Cited By ~ 10

Author(s):

O. RENNER ◽

I. USCHMANN ◽

E. FÖRSTER

Keyword(s):

Dense Plasma ◽

X Ray ◽

Dense Plasmas ◽

Plasma Diagnosis ◽

Bent Crystal ◽

Complex Information ◽

Diagnostic Potential ◽

Vertical Dispersion ◽

Fundamental Research

Modern experimental methods and instruments for X-ray spectral investigation of hot dense plasma provide complex information on environmental conditions in extreme states of matter. The basic spectroscopic conceptions for K-shell plasma diagnosis are outlined, the main characteristics of toroidally bent crystal spectrometers and vertical-dispersion instruments are briefly reviewed. Selected applications (monitoring and optimization of the emission from the femtosecond-laser-produced plasmas, characterization of colliding laser-exploded foils, spectral line merging, and continuum lowering in constrained-flow plasmas) demonstrate the usefulness of advanced spectroscopic methods for plasma diagnostics and fundamental research.

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Development of X-ray streak camera electronics at AWRE

Laser and Particle Beams ◽

10.1017/s0263034600001695 ◽

1986 ◽

Vol 4 (1) ◽

pp. 145-156 ◽

Cited By ~ 4

Author(s):

M. C. Jackson ◽

R. D. Long ◽

D. Lee ◽

N. J. Freeman

Keyword(s):

Streak Camera ◽

Sweep Rate ◽

Bragg Diffraction ◽

X Rays ◽

Crystal Spectrometer ◽

One Dimensional ◽

X Ray ◽

Ramp Generator ◽

Laser Facility ◽

User Facility

The paper reviews a number of X-ray streak cameras developed at AWRE. These cameras are used to provide temporal and one-dimensional spatial or spectral information on X-rays emitted from laser produced plasmas. Two of these cameras have been designed to be combined with other diagnostic instrumentation; one with a Wolter X-ray microscope (×22 magnification) and the other with a Bragg diffraction crystal spectrometer. This latter instrument provides a few eV spectral resolution and ∼15 ps temporal resolution; a typical experimental application at the AWRE HELEN laser facility will be described. The paper describes the circuitry of the bipolar avalanche transistor ramp generator used to drive the streak plates of the cameras. Improvements to this include: (a) increasing the fastest streak rate to ∼10 ps mm−1 by a distributed capacitance network across each of the bipolar stacks of transistors, and (b) reducing the trigger jitter to approximately ±10 ps by the use of a new mix of transistors in the stack and a Raytheon RS 3500 avalanche transistor. Additional improvements have now been added. These include a ‘half-scan’ user facility to aid initial camera timing and direct switching to select the sweep rate of the camera.

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Ray-tracing simulations of a bent crystal X-ray optics for imaging using laser–plasma X-ray sources

Laser and Particle Beams ◽

10.1017/s0263034604223072 ◽

2004 ◽

Vol 22 (3) ◽

pp. 253-259 ◽

Cited By ~ 8

Author(s):

L. LABATE ◽

M. GALIMBERTI ◽

A. GIULIETTI ◽

D. GIULIETTI ◽

L.A. GIZZI ◽

...

Keyword(s):

Ray Tracing ◽

Spatial Resolution ◽

Laser Plasma ◽

Imaging System ◽

Complex Pattern ◽

Careful Study ◽

Ray Optics ◽

X Ray ◽

Bent Crystal ◽

Laser Produced Plasma

Ray-tracing simulations of an optical X-ray system based on a spherically bent crystal operating in Bragg configuration for monochromatic projection imaging of thin samples are presented, obtained using a code developed for that purpose. The code is particularly suited for characterizing experimental arrangements routinely used with laser-produced plasma X-ray sources. In particular, the spatial resolution of the imaging system was investigated and a careful study of the complex pattern of the X-ray backlighting beam was performed.

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Some New Methods of Precision X-Ray Spectrometry

Advances in X-ray Analysis ◽

10.1154/s0376030800004080 ◽

1972 ◽

Vol 16 ◽

pp. 251-259 ◽

Cited By ~ 1

Author(s):

K. Das Gupta ◽

Herbert Welch ◽

P.F. Gott ◽

John F. Priest ◽

Sunny Cheng ◽

...

Keyword(s):

Focal Point ◽

Spectral Lines ◽

Background Intensity ◽

List Type ◽

Crystal Spectrometer ◽

X Ray ◽

Bent Crystal ◽

The Third ◽

Light Gathering Power ◽

In Series

AbstractThree novel methods of x-ray spectrometry have been developed in recent years at Texas Tech University. These are:1. Three crystal spectrometer2. Two curved crystal spectrometer3. Spherically bent crystal spectrometer.In this paper the new design features, and experimental results will be discussed to indicate the usefulness of the new instruments. The three crystal spectrometer is a modified two crystal instrument. A third crystal is used to analyze the output of the two crystal spectrometer. The first two crystals are operated as a standard two crystal spectrometer. The third crystal is swept through the spectrum transmitted by the first two crystals for each setting of the first two crystals. The peak intensity of the third crystal sweep corresponds to the energy setting of the two crystal spectrometer, and is the intensity used to plot the spectral lines. The two curved crystal spectrometer utilizes two transmission spectrographs with radii having a 2:1 ratio in series, the crystal with the smaller radius being set so that its focal point falls on the Rowland circle of the larger radius crystal, This instrument has a very low background intensity and is suitable for precision scattering and diffraetion work. The spherically bent crystal spectrometer makes use of high light gathering power and high orders of reflection to allow high resolution studies of weak spectral lines. It also has the advantage of ease of alignment and operation.

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