The PICOSEC Micromegas detector can time the arrival of Minimum Ionizing Particles with a sub-25 ps precision. A very good timing resolution in detecting single photons is also demonstrated in laser beams. The PICOSEC timing resolution is determined mainly by the drift field. The arrival time of the signal and the timing resolution vary with the size of the pulse amplitude.

Detailed simulations based on GARFIELD++ reproduce the experimental PICOSEC timing characteristics. This agreement is exploited to identify the microscopic physical variables, which determine the observed timing properties. In these studies, several counter-intuitive observations are made for the behavior of such microscopic variables. In order to gain insight on the main physical mechanisms causing the observed behavior, a phenomenological model is constructed and presented. The model is based on a simple mechanism of “time-gain per interaction” and it employs a statistical description of the avalanche evolution. It describes quantitatively the dynamical and statistical properties of the microscopic quantities, which determine the PICOSEC timing characteristics, in excellent agreement with the simulations. In parallel, it offers phenomenological explanations for the behavior of these microscopic variables. The formulae expressing this model can be used as a tool for fast and reliable predictions, provided that the input parameter values (e.g. drift velocities) are known for the considered operating conditions.

PICOSEC Micromegas检测器可以以低于25 ps的精度对最小电离粒子的到达时间进行计时。在激光束中也证明了在检测单个光子方面非常好的时序分辨率。PICOSEC定时分辨率主要由漂移场决定。信号的到达时间和定时分辨率随脉冲幅度的大小而变化。

基于GARFIELD ++的详细仿真再现了实验性的PICOSEC时序特性。利用该协议来识别微观的物理变量，这些变量确定了观察到的时序特性。在这些研究中，对此类微观变量的行为做出了一些与直觉相反的观察。为了深入了解导致观察到的行为的主要物理机制，构建并提出了一种现象学模型。该模型基于“每次交互的时间收益”的简单机制，并且采用了雪崩演化的统计描述。它定量地描述了微观数量的动态和统计特性，这些特性决定了PICOSEC的时序特性，并且与仿真非常吻合。在平行下，它为这些微观变量的行为提供了现象学的解释。如果已知输入参数值（例如，漂移速度）对于所考虑的运行条件，则表示该模型的公式可以用作快速可靠预测的工具。