共查询到19条相似文献,搜索用时 203 毫秒
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电子通过wiggler产生的辐射,除了短波辐射在轴线附近也有较强的长波辐射,在与轴线夹 角1/γ处达到最大.推导出wiggler长波辐射公式,理论分析了这种辐射的特点,并且将 理论分析的结果与数值计算的结果进行了比较.对在红外波长范围内电子束通过弯转磁铁和wiggler时产生的辐射强度和光通量作了计算,结果表明wiggler下的辐射强度和光通量均强 于弯转磁铁.比较了弯转磁铁的边沿辐射、波荡器的渡越辐射和wiggler长波辐射,表明wigg ler在红外波长范围辐射的性能最优.
关键词:
wiggler
波荡器
弯转磁铁
长波辐射 相似文献
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双—双绕螺旋线极化摇摆器磁场 总被引:1,自引:1,他引:0
本文提出了一种用双-双绕螺旋线圈实现线极化摇摆器磁场的新途径,给出了磁场的理论分析结果。对双-双绕螺旋线圈的磁场进行的实验测量所得结果与理论分析结果基本相符合 相似文献
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利用适用于线极化Bell-Bloom测磁系统的布洛赫方程和含有自旋弛豫的速率方程,以铯原子为研究对象,分析了抽运光对磁场灵敏度的影响,并在实验上分别采用与铯原子D1线和D2线共振的线偏光作为抽运光和探测光,用充有缓冲气体的气室进行了实验.实验结果与理论分析一致,均表明只有在一定的光强范围内,增大抽运光光强可以提高磁场灵敏度.且利用这一方法分析了原子的自旋弛豫对磁场灵敏度的影响.这项研究对于深入认识线极化的Bell-Bloom测磁系统,以及如何通过优化系统实现磁场灵敏度的提高具有重要的意义. 相似文献
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给出了双双绕螺旋线线极化Wiggler轴线上磁场的积分表达式,以此公式数字模拟此装置端口区的磁场分布,并进行了实验测定,结果表明,端口区磁场峰值突变和对称性均比圆极化好。另一方面,用洛仑兹运动方程,考虑了电子束空间电荷效应,证明此装置对电子束传输有自聚焦能力,给出了电子运动方程,电子束流与Wiggler峰值磁场的关系,数字模拟电子束运动轨迹也表明,此装置能自聚焦传输电子束,有希望应用于线极化自由电子激光实验中。 相似文献
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本文用单粒子理论方法,详细讨论了螺旋磁场近磁共振下的电子相空间运动方程和辐射场方程,得到了近磁共振下电子辐射的频率红移,谱线展宽和增益增强.我们的理论还适用于变周期和梯度螺旋磁场的情况. 相似文献
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对线极化摇摆场中,在有引导磁场或四极磁场时的电子轨迹特性、束流包络特性进行了解析分析和数值分析,推得了线极化摇摆场中的梯度漂移解析表达式,借助于Bogoliubov的非线性渐近法和奇异摄动法得到的解析分析结果与数值分析结果很好地吻合。 相似文献
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本文根据泊松方程用数值计算给出了电磁铁摇摆器的二维磁场分布,定量地讨论了磁极形状、磁隙大小、周期长短和电流大小等因素对峰值磁场强度的影响,重点讨论了如何根据二维磁场分布选择磁极形状才能提高峰值磁场强度和抑制磁饱和的问题。将计算的二维磁场分布和摇摆器磁场的理想波形相比较,可以帮助我们确定进入摇摆器的束流半径应该控制的范围。在对电磁铁摇摆器磁场二维数值计算的基础上,还探讨了适用ATA电子束的PALADIN摇摆器用于ETA电子束带来的结构设计和材料选择等问题。 相似文献
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A magnetic wiggler is studied in which each period of the magnetic field is produced by four magnet sections. A wiggler of this type can be used in the ring of an electron synchrotron.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 4, pp. 14–18, April, 1978. 相似文献
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Experimental and numerical studies of sheet electron beampropagation through a planar wiggler magnet
Ze-Xiang Zhang Granatstein V.L. Destler W.W. Bidwell S.W. Rodgers J. Chang S. Antonsen T.M. Jr. Levush B. Radack D.J. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1993,21(6):760-767
Detailed experimental studies on sheet relativistic electron beam propagation through a long planar wiggler are reported and compared with numerical simulations. The planar wiggler has 56 periods with a period of 9.6 mm. Typically, the wiggler field peak amplitude is 5 kG. The experimental efforts are focused on controlling the deviation of the beam toward the side edge of the planar wiggler along the wide transverse direction. It is found that a suitably tapered magnetic field configuration at the wiggler entrance can considerably reduce the rate of deviation. The effects of the following techniques on beam transport efficiency are discussed: side focusing, beam transverse velocity tuning at the wiggler entrance, and beam spread limiting. High beam transport efficiency (almost 100%) of a 15-A beam is obtained in some cases 相似文献
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The effects of self fields on gain for a free‐electron lasers (FELs) with electromagnetic‐wave wiggler and an axial guide magnetic field is presented. The relativistic equation of motion for a single electron for all relevant fields, including wiggler, self‐fields and axial guide magnetic field has been solved. Two classes of possible single‐particle trajectories in this configuration are found. Result of the numerical calculation shown that the relativistic part of group I (group II) orbits decreases (increases) monotonically with the axial field. The gain equations for the FEL configuration by adding the effect of self‐fields have been derived. The numerical calculation has been employed to analysis the gain induced by the effects of the self‐fields. It is shown that, for group I orbits the gain decreases in the presence of self‐fields and the gain decrement increases with increasing axial guide magnetic field, while for group II orbits the self‐fields enhances the gain. The gain decrement and enhancement are due to diamagnetic and paramagnetic effects of the self‐magnetic field, respectively. The comparison of the gain for electromagnetic‐wave wiggler with the gain in helical wiggler has been done (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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We present a new plasma-based method of guiding an electromagnetic pulse. The scheme consists of an inhomogeneous magnetic field and a uniform density plasma, in contrast to existing schemes that rely on transverse plasma density gradients but need not be magnetized. The refractive index of a magnetized plasma depends on the strength and direction of the magnetic field as well as the plasma density. A guiding channel is formed by using field inhomogeneity to generate the desired transverse profile of the index of refraction. The concept is analyzed with an envelope equation and, for the specific example of a wiggler magnetic field, with a two-dimension particle-in-cell simulation. A simplified model of this scheme as producing a magnetic wall in analogy to metallic waveguides is presented, for which corresponding approximate relations for the guided mode axial wavelength and radius are derived as functions of the plasma and magnetic field parameter. These are seen to be in good agreement with particle-in-cell simulation results. Since the desired inhomogeneity of the refractive index can be made easily when the electromagnetic wave frequency is close to the cyclotron frequency, this guiding scheme is most readily applied in the microwave regime. 相似文献
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Periodic magnetic structures (wigglers) have been successfully used for a long time for controlling beam parameters in charged-particle storage rings for various purposes (including the reduction of emittance). In this work, we optimize the optical functions of the storage ring gap into which a wiggler is installed for a more effective reduction of the emittance. Optimal solutions are obtained for the first time for FODOtype and theoretical minimum emittance (TME) structures. An original method is proposed for suppressing the contribution of the wiggler fields to the radiation excitation of the phase volume of the beam by modulating the field period along the wiggler axis. 相似文献
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毫米波自由电子激光的数值模拟和实验的比较 总被引:2,自引:0,他引:2
从波导管毫米波自由电子激光器的设计要求出发,根据Livermore实验室FRED程序的物理思想,编制了空间三维的数值模拟程序(WAGFEL)。为了检验程序的可靠程度,结合ELF装置的实际参数,进行了数值模拟并和实验结果进行了比较。结果表明,把Wiggler磁场B_w增大300 Gs后,WAGFEL程序的模拟结果和Livermore实验室的实验结果基本符合。模拟使用的全部参数,除B_w增大300Gs外,都是ELF的实际参数。模拟时峰值磁场B_w=4050Gs,实验测量峰值磁场B_w=3720Gs,相差在8%左右。WAGFEL程序可以用来从事毫米波自由电子激光器的设计以及基本物理问题的研究。 相似文献
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Mohandas K.K. Ravi Kumar A.V. Jain K.K. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》2000,28(3):621-625
An off-axis 50-period planar, short-wavelength (~10 mm) electromagnet wiggler is developed and characterized for millimeter-wave generation using a sheet electron beam in a free-electron laser experiment. Three-dimensional (3-D) magnetic field measurements of the electromagnet wiggler have been carried out. The measured wiggler magnetic field is 0.16 G/A ±3% while the mean value of wiggler wavelength is 0.998±3% cm. Due to off-axis arrangement of poles, there is a magnetic mirror field in the X direction, to confine the sheet beam 相似文献
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提出了一种新的高功率宽带放大器,它由速调管和自由电子脉塞组成,用永久周期磁铁聚焦。研究了这种器件的电子束聚焦、群聚和辐射。在速调管提供一阶调制系数为30%,波导管的半径1.51cm,摇摆器的磁场振幅0.16T,周期7.92cm,电子束的电压490kV,电流50A和半径0.368cm的条件下,预估这种器件的辐射波频率为11.4GHz,输出辐射功率为18MW,输出辐射带宽为44%。 相似文献