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使用天然Ⅱa型金刚石光电导探测器(PCD),测量激光等离子体发射的软X光辐射。由于探测器在200eV~2200eV之间具有平响应特性,可以不加滤片直接测量X光功率和能量。金刚石PCD与软X光能谱仪和平响应X光二级管的测量结果基本一致。 相似文献
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利用“星Ⅱ”0.35μm激光辐照铝靶,得到了对于不同激光功率密度亚千X光转换效率,并提出了一个简化理论模型,来解释0.35μm激光辐照铝靶X光转换效率。在这个模型中,由于热传损失激光能量,因此对于低功率密度激光,X光转换效率较低,同时对于高密度激光,由于等离子体喷射损失激光能量,因此转换效率也较低。 相似文献
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本文报导激光等离子体辐射X射线的测量方法和结果。在“星光”装置上,用1.6μm激光辐照Na/F和铜靶。用平晶谱仪测量等离子体辐射X射线绝对强度,并研究了辐射X射线强度与入射激光功率密度的关系,测量了靶前后辐射强度之比,为光电离机制的X光激光研究提供了较重要的数据。 相似文献
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讨论了利用激光等离子体产生水窗波段X光辐射的可能途径。靶材,即原子序数的选取是决定产生这一波段辐射的基本因素,利用激光等离子体的平衡态和非平衡态特性都可在水窗波段产生亮度X光辐射,提出利用黑体辐射来实现水窗波段X光显微成像研究的方案。 相似文献
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在LF-11和LF-12高功率激光装置上进行的实验中,设计了一些特定的激光束-金腔靶-探测器条件,创造了激光直接加热、准辐射加热和激光、X光混合加热三种物理条件,采用软X光透射光栅能谱时空分辨技术,测量了腔靶、缝靶和双孔靶等高分辨X光能谱,研究了激光等离子体X光辐射非平衡特性。 相似文献
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激光X光转换研究中解三温方程的两种差分格式 总被引:4,自引:1,他引:3
在激光X光转换规律的研究中必须认真讨论辐射的计算,本文提出了解电子,离子,光子三温相脱离的能量方程的两种差分格式,即隐式格式的整全迭代求解和分裂格式解法,文中介绍了能量交换项与其它项分开计算的分步方法,并考察了对温度变化的影响,数值计算表明结果是正确有效的。 相似文献
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双束黑洞靶辐射特性实验研究 总被引:1,自引:0,他引:1
本文着重介绍在“神光”装置上两路对打黑洞靶辐射特性实验研究。利用两台配置时标装置的亚千电子伏能谱仪(Dante)进行时间关联测量,分别监测双束靶吸收转换区和内爆压缩区泄漏X光谱脉冲波形、辐射能谱、辐射温度、辐射时间谱及其辐射温度随时间变化关系。同时进行了大量不同型号黑洞靶实验,给出吸收转换区辐射温度随注入激光能量面密度变化的关系曲线及其定标关系式。实验中,首次把掠入射平面反射镜用于亚千X光能谱测量,并取得预想的结果。 相似文献
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利用星光Ⅱ激光装置钕玻璃三倍频激光辐照金箔靶,实验研究了金箔靶背侧发射的X光能谱,时间过程和秀过激光能量。结果表明:金箔背侧发的X光可以作为一种较干净的强X光射源。 相似文献
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This paper presents the results of the influence of soft X-ray radiation on craters induced in SSNTDs by energetic α particles and protons of energy in the MeV range. We checked two detectors of the PM-355 and CR-39 types in order to verify and compare their resistance to the harsh conditions of high-temperature plasma experiments. To determine this effect some detector samples were first irradiated with α particles emitted from natural α particle sources and protons delivered by a particle accelerator. After that these samples were exposed to soft X ray radiation emitted from an X ray tube and also from the PF-1000 Plasma Focus facility. Doses during X ray irradiations varied from 0 up to tens of kGy. The irradiated samples were then etched in steps and track diameters were determined versus the absorbed dose and etching time and compared with those measured in samples not exposed to X ray radiation. 相似文献
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G. B. Hiremath A. S. Bennal M. M. Hosamani N. M. Badiger A. Trivedi M. K. Tiwari 《X射线光谱测定》2021,50(1):37-44
The L1, L2 and L3 subshells of Hf, Ta and Re atoms have been excited selectively by using microprobe XRF beam line, Indus‐2, RRCAT, India. The consequent characteristic L X‐ray photons, emitted from the targets due to creations of vacancies in L subshells, are measured using silicon drift detector (X‐123) spectrometer. As the energy of synchrotron radiation increases, the contribution of characteristic L X‐ray intensity increases. The advantage of the increase in the intensity of the characteristic L X‐ray photons with an increase in the energy of synchrotron radiation has been used to determine the L subshell fluorescence yield ratios of Hf, Ta and Re atoms by adopting the selective excitation method. The measured ratios of L subshell fluorescence yield have been compared with theoretical and other experimental values. 相似文献
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A mathematical model for the two‐layer composite Si‐Ge energy dispersive X‐ray detector is proposed, based on analyses of radiation and electron transport in the detector, and a mathematical model of an energy dispersive X‐ray fluorescent spectrometer with the detector is considered. The Monte Carlo method is applied to calculate probabilities of photon detection in different parts of the detector's response function. The composite detector with the time anti‐coincidence scheme is proposed; its first layer is Si detector, and the second layer is Ge detector. It is shown that this composite detector has some advantages, such as reduced Ge photo escape peaks intensities and efficiency of detection of high energy photons similar to efficiency of Ge detector. Applying the X‐ray detector for the energy dispersive X‐ray fluorescent spectrometer provides for a lower background level. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Fluorescence imaging of reactive oxygen species by confocal laser scanning microscopy for track analysis of synchrotron X‐ray photoelectric nanoradiator dose: X‐ray pump–optical probe 下载免费PDF全文
Bursts of emissions of low‐energy electrons, including interatomic Coulomb decay electrons and Auger electrons (0–1000 eV), as well as X‐ray fluorescence produced by irradiation of large‐Z element nanoparticles by either X‐ray photons or high‐energy ion beams, is referred to as the nanoradiator effect. In therapeutic applications, this effect can damage pathological tissues that selectively take up the nanoparticles. Herein, a new nanoradiator dosimetry method is presented that uses probes for reactive oxygen species (ROS) incorporated into three‐dimensional gels, on which macrophages containing iron oxide nanoparticles (IONs) are attached. This method, together with site‐specific irradiation of the intracellular nanoparticles from a microbeam of polychromatic synchrotron X‐rays (5–14 keV), measures the range and distribution of OH radicals produced by X‐ray emission or superoxide anions () produced by low‐energy electrons. The measurements are based on confocal laser scanning of the fluorescence of the hydroxyl radical probe 2‐[6‐(4′‐amino)phenoxy‐3H‐xanthen‐3‐on‐9‐yl] benzoic acid (APF) or the superoxide probe hydroethidine‐dihydroethidium (DHE) that was oxidized by each ROS, enabling tracking of the radiation dose emitted by the nanoradiator. In the range 70 µm below the irradiated cell, radicals derived mostly from either incident X‐ray or X‐ray fluorescence of ION nanoradiators are distributed along the line of depth direction in ROS gel. In contrast, derived from secondary electron or low‐energy electron emission by ION nanoradiators are scattered over the ROS gel. ROS fluorescence due to the ION nanoradiators was observed continuously to a depth of 1.5 mm for both oxidized APF and oxidized DHE with relatively large intensity compared with the fluorescence caused by the ROS produced solely by incident primary X‐rays, which was limited to a depth of 600 µm, suggesting dose enhancement as well as more penetration by nanoradiators. In conclusion, the combined use of a synchrotron X‐ray microbeam‐irradiated three‐dimensional ROS gel and confocal laser scanning fluorescence microscopy provides a simple dosimetry method for track analysis of X‐ray photoelectric nanoradiator radiation, suggesting extensive cellular damage with dose‐enhancement beyond a single cell containing IONs. 相似文献