The carbon thin film as a target for laser‐driven heavy ion acceleration has been developed using the carbonization of polyimide induced by the irradiation of a XeCl excimer laser. The relationship between the depth of the crater produced by the laser irradiation and the laser fluence were measured in order to clear the carbonization mechanisms of polyimide. The melting threshold of polyimide was estimated to 0.058 J/cm². It is found that the carbonization is induced by the irradiation with the laser fluence around or under the threshold.

中文翻译：

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使用XeCl准分子激光器开发用于激光驱动重离子加速的碳薄膜

利用XeCl准分子激光辐照引起的聚酰亚胺碳化，开发出了以激光驱动重离子加速为目标的碳薄膜。为了消除聚酰亚胺的碳化机理，测量了由激光照射产生的弹坑深度与激光能量密度之间的关系。聚酰亚胺的熔融阈值估计为0.058J / cm ²。发现碳化是通过在阈值附近或阈值以下的激光注量辐照引起的。