The optimization of a transmission type bremsstrahlung conversion target was carried out with Monte Carlo code FLUKA for intense pulsed electron beams with electron energy of several hundred keV for maximum photon fluence. The photon emission intensity from electrons with energy ranging from 300 keV to 1 MeV on tungsten, tantalum and molybdenum targets was calculated with varied target thicknesses. The research revealed that higher target material element number and electron energy leads to increased photon fluence. For a certain target material, the target thickness with maximum photon emission fluence exhibits a linear relationship with the electron energy. With certain electron energy and target material, the thickness of the target plays a dominant role in increasing the transmission photon intensity, with small target thickness the photon flux is largely restricted by low energy loss of electrons for photon generation while thick targets may impose extra absorption for the generated photons. The spatial distribution of bremsstrahlung photon density was analyzed and the optimal target thicknesses for maximum bremsstrahlung photon fluence were derived versus electron energy on three target materials for a quick determination of optimal target design.

使用 Monte Carlo 代码 FLUKA 对具有数百 keV 电子能量的强脉冲电子束进行透射型轫致辐射转换靶的优化，以获得最大光子注量。用不同的靶厚度计算了钨、钽和钼靶上能量范围为 300 keV 至 1 MeV 的电子的光子发射强度。研究表明，较高的目标材料元素数和电子能量会导致光子注量增加。对于某种靶材，具有最大光子发射注量的靶材厚度与电子能量呈线性关系。在一定的电子能量和靶材的情况下，靶材的厚度对增加透射光子强度起主要作用，对于小目标厚度，光子通量很大程度上受到用于产生光子的电子能量损失低的限制，而厚目标可能会对产生的光子施加额外的吸收。分析了轫致辐射光子密度的空间分布，并推导出了三种靶材上最大轫致辐射光子通量的最佳靶材厚度与电子能量的关系，以便快速确定最佳靶材设计。