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高电离态原子光谱测量 总被引:2,自引:0,他引:2
简要介绍了兰州重离子加速器上的高电离态原子光谱实验测量和取得的部分实验结果.The excitation spectra and level lifetimes of highly charged atoms for heavier elements of Ne, S and Ar have been measured by using the beam foil method on the heavy ion accelerator in Lanzhou. Emission spectra in the wavelength region of 25-400 was studied. On the whole, the agreement between our experimental results and other experiments is fairly good. 相似文献
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结合天体等离子体中铝发射谱和某些能级寿命的测量,对束箔光谱技术可为天体物理学研究提供重要信息和重要性进行了简述 相似文献
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在原子能院串列加速器上,利用束箔方法,测量了能量为30MeVFe离子产生的高剥离态谱线跃迁结构的寿命值。在30MeV时,Fe通过箔膜的电荷态分布在7+到17+,我们选择Fe XVI 2p6 (1S) 4p -2p6 (1S) 5d(2P°3/2 -2D3/2)的谱线,谱线波长124.696 Å,能级寿命为79±4ps。并对实验误差进行了分析。 相似文献
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为实现重离子肿瘤治疗临床实验中对照射束流状态的实时监测,研制了束流强度及剂量监测系统,包括积分电离室、后续电流频率转换电路及LabVIEW数据获取处理三部分。利用闪烁体探测器和标准剂量计测试了系统的线性响应和得到剂量的准确性,结果表明:系统在束流临床照射流强范围内的线性响应好于90%,其实时反馈的临床照射剂量偏差小于5%。同时束流强度及剂量监测系统与安全控制系统相结合,保证束流照射状态满足临床照射的安全要求。 相似文献
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A new Digital Pulse Processing(DPP) module has been developed, based on a domino ring sampler version 4 chip(DRS4), with good time resolution for La Br3 detectors, and different digital timing analysis methods for processing the raw detector signals are reported. The module, composed of an eight channel DRS4 chip, was used as the readout electronics and acquisition system to process the output signals from XP20D0 photomultiplier tubes(PMTs). Two PMTs were coupled with La Br3 scintillators and placed on opposite sides of a radioactive positron22 Na source for 511 ke V γ-ray tests. By analyzing the raw data acquired by the module, the best coincidence timing resolution is about 194.7 ps(FWHM), obtained by the digital constant fraction discrimination(d CFD) method,which is better than other digital methods and analysis methods based on conventional analog systems which have been tested. The results indicate that it is a promising approach to better localize the positron annihilation in positron emission tomography(PET) with time of flight(TOF), as well as for scintillation timing measurement,such as in TOF-?E and TOF-E systems for particle identification, with picosecond accuracy timing measurement.Furthermore, this module is more simple and convenient than other systems. 相似文献
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设计了一款小型化、低噪声、大动态范围的前端处理电路,包括电荷灵敏前放、成形放大电路、单道脉冲幅度分析电路。前放的等效输入噪声≤1.5 keV,动态范围可达0~11 V,积分非线性 ≤0.11%。该电路为模块化电路,当前放与主放模块构成系统时,其分辨可以达到0.12%。当前放、主放模块与中国科学院近代物理研究所制作的离子注入型硅探测器构成系统时,采用239Pu 源进行测试,测得在5.157 MeV时的能量分辨约为0.82%;当主放、单道脉冲幅度分析模块与中国科学院近代物理研究所制作的碘化铯晶体探测器构成系统时,采用60Co 源进行测试,对于能量为1.332 MeV 的 射线,测得其能量分辨约为7.9%。该电路可用于半导体探测器、光电倍增管及电子倍增器等探测器信号的处理。目前,小型前端电路已经应用于中国科学院近代物理研究所自行研制的便携式盐湖卤水铀、钍、钾快速测量仪的原型样机,达到了预期效果。A small dimension front-end circuit with low noise and wide output dynamic range is introduced in this paper. The front-end circuit is made up of a charge sensitive preamplifier, a shaping circuit and a single channel pulse height analyzer. The equivalent input noise is under 1.5 keV. The output integral nonlinearity is less than 0.11% within the dynamic range of 011 V. And the circuit can be suitable for different conditions by different modules. The resolution was about 0.12% with the charge sensitive preamplifier and the main amplifier. The energy resolution of 0.82% was achieved for 5.157 MeV -rays from a 239Pu source with the charge sensitive preamplifier, the main amplifier and anion-injection silicon detector designed by the Institute of Modern Physics(IMP). An energy resolution of 7.9% was achieved for 1.332 MeV rays from a stationary 60Co source with the main amplifier, the single channel pulse height analyzer and a CsI scintillator detector designed by the IMP. The front-end circuit has the features of wide output dynamic range, simple structure, high level of integration,small dimensions, low noise, fast rise time of the output pulse and excellent stability. The front-end circuit can be applied to signal processing of semiconductor detectors, photomultiplier tubes and electrons multiplier. And the front-end circuit had been applied to a prototype of the portable rapid measuring instrument designed by IMP for measuring Uranium, Thorium and Potassium in the salt lake brine with goodtest result. 相似文献