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电子能谱的测量是电子加速器性能检测的重要环节。本文设计了一种新的测量方法--多层吸收法来对电子能谱进行测量,它是基于在辐照电子加速器上应用最多的射程法,加入Monte-Carlo模拟和迭代算法而重建出入射电子能谱的一种方法。该方法具有操作简便、测量准确、无需复杂设备等优点。本文用该方法对6 MeV加速器的电子能谱进行了测量,得到了较好的结果,且与磁谱仪的测量结果在误差范围内符合得很好,验证了其可行性。 相似文献
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一台2.2MeV电子辐照加速器的防护门设计 总被引:1,自引:0,他引:1
本文简要介绍了一台电子能量为2.2MeV,束流强度为25mA的电子辐照加速器的辐射防护设计。其主要内容是防护门设计中考虑的原则和计算方法。最后给出的计算结果是:辐照室防护门为12cm铁;加速器室防护门算了几个结果,供加速器人员根据束流损失情况进行选择。 相似文献
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研究了辐照电子直线加速器辐射剂量测定的技术方法,在测量方法上采取实测与蒙特卡洛模拟计算相结合的方法提高辐射剂量测定的准确度和可操作性;用化学剂量计建立电子束吸收能量测量的方法;用平板电离室建立电子束表面剂量、电子束吸收剂量率测量的方法;用半导体探测器阵列建立电子束辐照均匀性测量的方法。 相似文献
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CL2100C医用电子直线加速器机房的防护设计 总被引:1,自引:0,他引:1
介绍了CL2100C医用电子直线加速器的治疗室在辐射防护方面的需求和防护设计;对影响防护的各种因素,如射线能量,剂量率,工作负荷,使用因子和占用因子等进行了讨论;在加速器的正常和极限工作条件下对辐射水平进行了测量。 相似文献
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根据射程法原理,在上海二级标准剂量学实验室对辐射加工用加速器电子束能量的测量方法进行了实验研究,并在3个辐射工厂对3台3MeV、20mA高频高压型加速器的电子束进行了能量测定.结果表明,在1-3MeV能量范围内,能量测定准确度优于±10%. 相似文献
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衰减法测量静电加速器电子束能量 总被引:2,自引:2,他引:0
研制了薄壁平行板透射电离室,研究了透射电离室的特性。用透射电离室测量静电加速器电子束在铝中的透射分布,得到不同高压下电子束在铝中的外推射程,进而确定电子束能量。 相似文献
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电子辐照加速器主要用于对物品的消毒灭菌、材料改性、食品保鲜等,不同能量、不同功率的电子柬流对辐照效果有较大影响。扫描盒出口处,扫描成电子帘的束流大小和扫描宽度,对辐照物品有直接的关系,因此,电子帘的测量在加速器应用中十分重要。 相似文献
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B.S. Dassanayake S. DasA. Ayyad R.J. BereczkyK. T?kési J.A. Tanis 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2011,269(11):1243-1247
Charge (time) evolution and the angular dependence of incident electrons in the range 300-1030 eV through a single macroscopic glass capillary was studied. Charge measurements were done at a sample tilt angle of ψ = 2? for observation angles θ = 0? and 0.5? (both ψ and θ were measured with respect to the incident beam direction) at incident energies of 520.7 and 824.5 eV using a parallel-plate spectrometer. After equilibrium of transmission, electrons had lower average centroid (mean) energies than the respective primary beam values. Centroid energies of transmitted electrons at the centroid of the angular distribution (where the observation angle θ is nearly equal to tilt angle of the sample ψ) were found to decrease exponentially with increasing sample tilt angles for all the measured electron energies. This energy loss is attributed to inelastic scattering of electrons with the inner wall of the sample close to the capillary entrance. Furthermore, the centroid energies of the transmitted electron angular distributions at 520.7 eV were found to lose energy for angular positions away from the capillary axis (angular centroid position) for all tilt angles, indicating a higher degree of inelastic scattering at the edges of the angular distributions. 相似文献
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S.J. Wickramarachchi B.S. DassanayakeD. Keerthisinghe A. AyyadJ.A. Tanis 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2011,269(11):1248-1252
Transmission of 500, 800, and 1000 eV electrons through a tapered Borosilicate glass capillary was studied for the first time. Interestingly, almost no transmission was seen for the lowest energy (500 eV), while electrons were transmitted for the higher two energies. The time (charge) dependence of the electron transmission intensity at 1000 eV was examined for tilt angles up to 1.0° with sudden bursts of elastic transmission at the lower sample tilt angles occurring. No stable equilibrium was seen even at long charge times for the measured tilt angles. The results reveal unique features of electron transmission through tapered glass capillaries compared to what has been observed for highly charged ions and electrons so far. 相似文献
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Fleetwood A. Fleetwood R. Kerris K. Merkel G. Smith M. 《IEEE transactions on nuclear science》1988,35(6):1294-1299
A thermoluminescent dosimeter electron range measurement technique has been used to measure the energy distribution of relativistic electrons in a diffuse e-beam. The doses produced by the e-beam at 12 aluminum absorber thicknesses have been measured. The experimental technique is described. Angular distributions of the electrons have also been obtained. The technique has been used to investigate a relativistic electron beam that has emerged from the steel exit port of a drift tube filled with He gas at a pressure below 1 torr. The sensitivity of the measuring technique to the beam energy and angular distribution has been investigated. The experimental results are compared to Monte Carlo calculations. The results are sensitive to maximum e-beam energy and can be used to explore e-beam physics 相似文献
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电子束在MOS结构中的能量沉积与辐照效应 总被引:2,自引:0,他引:2
根据电子输运“双群理论”计算出电子在Si-SiO2材料中的能量沉积。用与硅等2效的外推电离室测定了1.0MeV和1.5MeV的电子束在MOS电容芯片中的吸收剂量。用X光电子谱、俄歇谱、深能级瞬态谱和C-V方法测量分析了MOS电容Si-SiO2材料化学结构,界面态密度和C-V曲线在辐射前后的变化,根据理论和实验结果,从辐射剂量学的角度分析讨论了电子能量沉积,电离缺陷和辐射效应间的关系,并提出一个关于 相似文献
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Y.G. Li Z.M. Zhang 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2009,267(2):215-220
The electron Rutherford backscattering spectra and high-energy reflection electron energy loss spectra have been calculated by a Monte Carlo method for bulk solids and overlayer/substrate systems. The simulation model is mainly based on the use of Mott cross section for elastic scattering and the use of Penn’s dielectric functional approach to the electron inelastic scattering inside the solid. Moreover, it has further considered the recoil energy loss of energetic electrons and the thermal vibration of atoms with an isotropic distribution of the velocity direction. The calculated energy loss spectra for Al/Pt and Al/Mo agree with the experimental spectra quite well. The signals owing to different kinds of atoms can be separated by taking the scatter for the maximum-scattering angle event along an electron trajectory as the Rutherford backscattering atom, enabling a theoretical estimation of the peak intensity ratio. Furthermore, the simulation has also indicated that the multiple scattering is the dominant process to the quasi-elastic and energy loss of the electrons and is responsible mainly to the difference on the peak intensity between the linear model and experiment. 相似文献
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An indirect method is proposed for measuring the relative energy spectrum of the pulsed electron beam of a plasma focus device. The Bremsstrahlung x-ray, generated by the collision of electrons against the anode surface, was measured behind lead filters with various thicknesses using a radiographic film system. A matrix equation was considered in order to explain the relation between the x-ray dose and the spectral amplitudes of the electron beam. The electron spectrum of the device was measured at 0.6 mbar argon and 22 k V charging voltage, in four discrete energy intervals extending up to 500 ke V. The results of the experiments show that most of the electrons are emitted in the 125–375 ke V energy range and the spectral amplitude becomes negligible beyond 375 ke V.? 相似文献
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研究基于简单解析表达式的电子背散射系数与入射电子能量、介质厚度和能损的关系及其对电子束辐射加工的影响,考虑到入射电子在多层介质之间反复的穿透和背散射,编制了ED410程序,计算了不同补底材料和不同入射电子能量下能量沉积的深度分布和剂量因子,利用补底要 背散射抬高接近补底界面处的剂量,较大地改善了辐射加工的均匀性。 相似文献
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研制了一台电子能量损失谱仪用的中高能电子枪。其产生的电子与原子、分子发生碰撞,通过谱仪收集、分析散射电子的动量和能量,可以获得靶的电子结构和碰撞动力学信息。该电子枪结构简单,由热阴极、栅极、阳极、聚焦极和偏转板组成;电子能量可调范围大(1-3 keV),操作简单。为了获得最优的束流条件,利用SIMION电子光学软件模拟了电子发射源大小和初始发散角对靶点处的束斑大小和束流发散角的影响。在电子能量为1.5 keV条件下,实验检验给出在离电子枪出口27 mm处可获得束径约为0.95 mm、束流发散角约0.93°和束流强度6.27mA的电子束,满足电子能量损失谱仪的使用要求。 相似文献
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