- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Pixel-to-pixel variation on a calibrated PILATUS3-based multi-energy soft x-ray detector
摘要： A multi-energy soft x-ray pin-hole camera based on the PILATUS3 100 K x-ray detector has recently been installed on the Madison Symmetric Torus. This photon-counting detector consists of a two-dimensional array of ～100 000 pixels for which the photon lower-threshold cutoff energy Ec can be independently set for each pixel. This capability allows the measurement of plasma x-ray emissivity in multiple energy ranges with a unique combination of spatial and spectral resolution and the inference of a variety of important plasma properties (e.g., T e, nZ, Z eff). The energy dependence of each pixel is calibrated for the 1.6–6 keV range by scanning individual trimbit settings, while the detector is exposed to ?uorescence emission from Ag, In, Mo, Ti, V, and Zr targets. The resulting data for each line are then ?t to a characteristic "S-curve" which determines the mapping between the 64 possible trimbit settings for each pixel. The statistical variation of this calibration from pixel-to-pixel was explored, and it was found that the discreteness of trimbit settings results in an effective threshold resolution of ?E < 100 eV. A separate calibration was performed for the 4–14 keV range, with a resolution of ?E < 200 eV.
关键词： energy calibration,x-ray detector,photon-counting,multi-energy soft x-ray,plasma x-ray emissivity,PILATUS3
更新于2025-09-23 15:21:21
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A computational tool for simulation and design of tangential multi-energy soft x-ray pin-hole cameras for tokamak plasmas
摘要： A new tool has been developed to calculate the spectral, spatial, and temporal responses of multi-energy soft x-ray (ME-SXR) pinhole cameras for arbitrary plasma densities (ne,D), temperature (Te), and impurity densities (nZ). ME-SXR imaging provides a unique opportunity for obtaining important plasma properties (e.g., Te, nZ, and Z eff) by measuring both continuum and line emission in multiple energy ranges. This technique employs a pixelated x-ray detector in which the lower energy threshold for photon detection can be adjusted independently. Simulations assuming a tangential geometry and DIII-D-like plasmas (e.g., ne,0 ≈ 8 × 1019 m?3 and T e,0 ≈ 2.8 keV) for various impurity (e.g., C, O, Ar, Ni, and Mo) density pro?les have been performed. The computed brightnesses range from few 102 counts pixel?1 ms?1 depending on the cut-off energy thresholds, while the maximum allowable count rate is 104 counts pixel?1 ms?1. The typical spatial resolution in the mid-plane is ≈0.5 cm with a photon-energy resolution of 500 eV at a 500 Hz frame rate.
关键词： tokamak plasmas,multi-energy soft x-ray,plasma diagnostics,pinhole cameras,x-ray spectra
更新于2025-09-10 09:29:36