双向四电子束泵浦KrF主放大器能量沉积

Electron Energy Deposition for KrF Laser with Bidirectional Four e beams Pump

用三维电子输运Ｍｏｎｔｅ－Ｃａｒｌｏ（ＭＣ）方法研究了双向四电子束泵浦ＫｒＦ准分子激光器ＭＯＰＡ系统中主放大器（Ｈ１Ｍ）的能量沉积空间分布。计入了Ｈｉｂａｃｈｉ结构和主膜的影响。对０．５ＭｅＶ的电子，泵浦方向能量沉积基本均匀，而在轴向，因为两窗口间的１４ｃｍ“死区”使得能量沉积呈“马鞍形”，峰谷比为２～３。给出了能量沉积的总量及能量沉积效率与电子束能的关系曲线，为Ｍａｒｘ发生器的二极管电压进行优化设计提供了依据。

The spatial profile of the energy deposition for the main amplifier (H1M) of a KrF laser MOPA system is presented by meams of 3D Monte Carlo method. The effects of Hibachi structure and main foils are considered. For 0.5 MeV electron, the energy deposition distributions of pumping direction are almost uniform. In the lasing direction (axial), because of a 14 cm unpumped area between two e beam windows the spatial profile of energy deposition takes the shape of a saddle. The peak valley ratio is 2～3. In addition, the relations of the total deposition energy and the energy deposition efficiency with the e beam energy are given. The total deposition energy and the energy deposition efficiency reach the maximum when the e beam energy is equal to 0.5 MeV and 0.31 MeV, respectively.