Integration and characterization of Readout Electronics System for dN/dx Measurement with Drift Chamber Prototype

Abstract

To explore the feasibility of high-precision particle identification using the cluster counting technique for the drift chamber, a dedicated readout electronics system with low noise, high bandwidth, and high sampling rate is required. This paper presents the design and performance evaluation of a scalable readout prototype developed for this application. The system architecture integrates a custom front-end with a $1.3\ \text{GSps}$ waveform sampling backend, implemented within a modular 120-channel framework. Laboratory characterization of the 40-channel prototype demonstrates a $-3$ dB analog bandwidth of $460\ \text{MHz}$ and an Equivalent Noise Input current of $0.81\ μ\text{A}_\text{rms}$. These specifications are essential for preserving the fast temporal features of ionization signals. Furthermore, the system achieves an intrinsic timing jitter of $0.87\ \text{ns}$, which satisfies the timing precision requirements for drift distance measurement. Joint experiments with a drift chamber prototype using cosmic rays verified the system's capability to resolve discrete ionization peaks within piled-up waveforms. These results confirm that the readout electronics provide the signal fidelity and temporal resolution necessary for future cluster counting algorithm development.

Figures (15)

• Figure 1: Block diagram of the readout electronics for the drift chamber demonstrator.
• Figure 2: (a) Photograph of the drift chamber prototype. (b) Wire layout of the drift chamber, displaying the precise arrangement of 120 anode sense wires and 416 cathode field wires.
• Figure 3: 10-channel preamplifier board implemented with $50\ \Omega$ input termination and two-stage voltage amplification.
• Figure 4: Photograph of the 10-channel readout unit comprising the ADC mezzanine and FPGA carrier.
• Figure 5: Block diagram of the signal distribution and trigger logic.