# Multigap Resistive Plate Chambers for Time of Flight Applications
## 3 Applications in Large Experiments
### A Brief Summary  
The main properties of the MRPC detectors used in large experiments are summarized in Table 3. The efficiency of all these MRPCs is very close to 100%, which is quite good. MRPCs with a gap thickness of around 0.25 mm can reach a time resolution of 60 ps, while much thinner gaps and a higher working field can lead to a time resolution better than 20 ps. The rate capability of MRPCs made of the float glass sheet is typically below 1 kHz/cm\({}^{2}\). MRPCs based on the low resistive glass (\(\rho\sim 10^{10}\)\(\Omega\) cm), which can reach a rate of up to 70 kHz/cm\({}^{2}\), are considered by CBM and future experiments. The main solution for the present readout electronics is a combination of amplifier and TDC, shown in Table 4. Their overall time jitters are usually around 20 ps. The ToT  
Figure 16: The cross-section view of the sealed MRPC. Reproduced with permission from [PERSON] et al., Journal of Instrumentation; published by IOP Publishing for Sissa Medialab, 2020 [100]. Figure 15: The time resolution results of the thin-gap MRPC Reproduced with permission from [PERSON] et al., Journal of Instrumentation; published by IOP Publishing for Sissa Medialab, 2020 [97]. **(a)** Time distribution at \(E=156\) kV/cm for the ComLSTM neural network. The blue line shows the distribution of the time difference and the red line is obtained from the gaussian fitting. **(b)** Time resolution with the change of the working field. The black markers and curves show the results given by the threshold method, while the red markers and curves given by the ComLSTM. method is regularly used to acquire the arriving time of a signal, and the time-amplitude effect should be corrected. For future experiments such as SoLID and EIC, to achieve ultra-high time resolution, an MRPC detector with many thin gaps and the signal sampling technology are proposed. Thanks to the full signal sampling techniques, neural networks can be used to reconstruct the detector time. When you start digging into the operation of MRPC detectors, there are many important issues that should be well noticed and investigated. The working point varies for MRPCs with different structures and working conditions. For example, the wide-gap (\(\sim\)0.25 mm) MRPC in avalanche mode usually operates at the electric field of around 110 kV/cm, while the very thin-gap (\(\sim\)0.1 mm) MRPC can work well at 150 kV/cm to achieve a good resolution; the working point will shift significantly for different gas mixtures [101; 102; 103; 104; 105]; MRPCs built with different resistive materials may have different working voltage and efficiency plateau: we can see from ref. [102] that the 6-gap MRPC with low-resistivity glass reaches the plateau at the electric field of around 110 kV/cm and the normal 6-gap MRPC reaches its plateau at a higher electric field of 120 kV/cm. In addition, temperature and pressure have a significant influence on the operation and performance of MRPC detectors. On one hand, the temperature will affect the resistivity of the electrode and hence influence the resistor--capacitance circuit and the current of the detector [106]. The resistivity generally decreases by order of magnitude for a temperature increase of about 20 \({}^{\circ}\)C both for Bakelite and float glass, as shown in Figure 17a, and it has a direct effect on the chamber's rate capability [107; 108]. On the other hand, the gas parameters (such as drift velocity and Townsend coefficient) are determined by the gas mixtures and their working electric field \(E\), temperature \(T\) and pressure \(P\). If the environmental conditions change, the working voltage of the MRPC detector needs to be adjusted to keep MRPC