【摘要】 给出了利用叠片法测量“闪光二号”加速器高功率离子束能谱的基本原理及初步实验结果.采用Ziegler的拟合公式编制程序计算了不同能量质子和碳离子穿过不同厚度Mylar膜后的能量损失情况.在偏压法拉第筒阵列各个法拉第筒的准直孔前分别覆盖0—6μm厚的Mylar膜,根据不同膜厚对应的信号衰减情况(叠片法),得到了高功率离子束的离子能谱,离子的最高能量>440keV,平均能量约为270keV,能量为200—300keV之间的离子数目最多,碳离子数和90keV以下的质子所占总离子数的组分不多于32%.所测量离子能谱和离子数目随时间的分布关系与二极管的电压和电流符合也较好.还将叠片法的测量结果与利用磁谱仪和采用飞行时间法等的测量结果进行了比较,三种方法所得的测量结果基本一致.更多还原

【Abstract】 The preliminary experimental results obtained for the energy spectra of high-power ion beam(HPIB) with a pile of thin films on FLASH Ⅱ accelerator are reported. Code was developed to calculate the theoretical energy-loss of proton and C ion beams transmited through the Mylar films with different thickness. The apertures of Faraday Cups are covered with Mylar films of different thickness, and then the signal attenuations can be recorded with oscilloscope. The energy spectra of HPIB and the diode voltage are obtained according to the signal allenuations. The diode voltage measured with a pile of thin films agrees with the voltage measured with a differential ring. And the ion number versus time curve was given. In addition, the ion energy of HPIB is also measured with Thomson spectrometer and time of flight method and the results agree with those measured with a pile of thin films.更多还原