Calibration and characterization of single photon counting cameras for short-pulse laser experiments

Abstract

The photon counting efficiency of various CCD based cameras was studied as a function of xray energy and exposure. A pair of Spectral Instruments Model 800 CCD cameras fitted with 16 µm thick back-illuminated CCDs were calibrated at low x-ray energy using two well established histogram methods, a standard pixel for pixel histogram and the single pixel event histogram method. In addition, two new thick substrate CCDs were evaluated for use at high energy. One was a commercially available Princeton Instruments LCX1300 deep depletion CCD camera while the other was a custom designed 650 µm thick partially depleted CCD fitted to a SI 800 camera body. It is shown that at high x-ray energy, only a pixel-summing algorithm was able to derive spectral data due to the spreading of x-ray events over many pixels in the thicker substrate CCDs. This paper will describe the different algorithms used to extract spectra and the absolute detection efficiencies using these algorithms. These detectors will be very useful to detect high-energy x-ray photons from high-intensity short pulse laser interactions.

Electron Generation and Transport in Intense Relativistic Laser-Plasma Interactions Relevant to Fast Ignition ICF

“…The energy within pixels that are counted as hits can then be multiplied by the work function of the chip material and the gain of the camera to give an energy spectrum. The chip efficiency, ef f , which is a function of the photon energy (in our case, we are interested in the Kα photons) and the chip coverage, has been determined through extensive CCD calibrations [72]. The other variables in the equation will be a function of the individual experiment or shot setup.…”

“…Below 100 keV, most photons will deposit their energy in one pixel. In this mode, then, the value of each pixel will be proportional to the energy deposited by the photon [71,72]. By taking a histogram of the pixel readout values, an approximation can be made of the x-ray spectrum.…”

Hard x-ray transmission curved crystal spectrometers (10–100 keV) for laser fusion experiments at the ShenGuang-III laser facility

“…The α-quartz crystals that we used were symmetrically cut into thin slices with the (11)(12)(13)(14)(15)(16)(17)(18)(19)(20) surface plane and the (10-11) edge plane. Since thinly sliced quartz is elastic at room temperature, it can be bent without additional heating.…”

“…Solid-state detectors of single-photon counting CCDs (3-30 keV) [11] , dispersive x-ray detectors of transmission curved crystal spectrometers (10-120 keV) [12] , and nondispersive x-ray detectors with filters, such as Ross pairs spectrometers (18-90 keV) [13,14] , filter stack spectrometers (12-700 keV) [15,16] and filter-fluorescer spectrometers (20-220 keV) [17,18] are the conventional approaches for hard x-ray spectra diagnostics. The dispersive x-ray detectors of transmission curved crystal spectrometers are superior, especially in the 10-120 keV range which is more applicable to laser fusion experiments, due to their high spectral resolution, broad energy coverage, and robustness in harsh environments.…”

A dual channel X-ray spectrometer for fast ignition research

“…This camera was previously calibrated at 5.9 keV and 22 keV using Fe-55 and Cd-109 sources [20]. The SI800 CCD was located at a distance of 5.20 m at an angle of 23 degrees with respect to the normal to the front surface of the target.…”