High intensity ultrashort laser pulses interacting with thin solid targets are able to produce energetic protons and ions by means of extremely large accelerating fields, generated by escaping electrons. The characterization of such electrons is thus a key factor for the understanding of the accelerating potential temporal evolution. Here, we present temporally resolved measurements of the ultrafast escaping electron component. The charge, electric field, and temporal duration of the emitted ultrafast electron beams are determined using temporal diagnostics with a 100 fs temporal resolution. Experimental evidence of scaling laws for the ultrafast electron beam parameters with respect to the incident laser pulse energy is retrieved and compared with theoretical models, showing an excellent agreement.High intensity ultrashort laser pulses interacting with thin solid targets are able to produce energetic protons and ions by means of extremely large accelerating fields, generated by escaping electrons. The characterization of such electrons is thus a key factor for the understanding of the accelerating potential temporal evolution. Here, we present temporally resolved measurements of the ultrafast escaping electron component. The charge, electric field, and temporal duration of the emitted ultrafast electron beams are determined using temporal diagnostics with a 100 fs temporal resolution. Experimental evidence of scaling laws for the ultrafast electron beam parameters with respect to the incident laser pulse energy is retrieved and compared with theoretical models, showing an excellent agreement.

中文翻译：

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直接观察高强度激光-物质相互作用产生的超快电子

与薄固体目标相互作用的高强度超短激光脉冲能够通过逃逸电子产生的极大加速场产生高能质子和离子。因此，这种电子的表征是理解加速电位时间演化的关键因素。在这里，我们提出了超快逃逸电子分量的时间分辨测量。发射的超快电子束的电荷、电场和时间持续时间使用具有 100 fs 时间分辨率的时间诊断来确定。检索了超快电子束参数相对于入射激光脉冲能量的标度定律的实验证据，并与理论模型进行了比较，显示出极好的一致性。与薄固体目标相互作用的高强度超短激光脉冲能够通过逃逸电子产生的极大加速场产生高能质子和离子。因此，这种电子的表征是理解加速电位时间演化的关键因素。在这里，我们提出了超快逃逸电子分量的时间分辨测量。发射的超快电子束的电荷、电场和时间持续时间是使用具有 100 fs 时间分辨率的时间诊断确定的。检索了超快电子束参数相对于入射激光脉冲能量的标度定律的实验证据，并与理论模型进行了比较，显示出极好的一致性。