Speaker
Description
Flavor physics and jet measurements at the Circular Electron Positron Collider (CEPC) impose stringent requirements on particle identification (PID). The drift chamber is a key candidate for the tracker, and primary ionization cluster counting (dN/dx) offers superior PID by resolving individual ionization clusters. Simulations indicate that an optimized dN/dx drift chamber can achieve K/π separation exceeding 3σ for momentum up to 20 GeV/c.
To investigate this technique, a multi-channel drift chamber prototype was developed, using 20 μm gold-plated tungsten sense wires and 70 μm aluminum field wires. The wire parameters and cell dimensions maintain complete compatibility with the CEPC drift chamber design parameters. Concurrently, a 1.3 Gsps high-speed readout electronics system with high bandwidth and low noise characteristics has been developed, together with a DAQ system. The readout chain ensures faithful capture of fast ionization signals and supports multi-channel parallel acquisition.
The hardware system provides an experimental foundation for studying the primary ionization counting method. Initial commissioning and cosmic-ray tests confirmed the electronics performance and reliable operation of the prototype, while subsequent beam tests using muon, pion, and kaon beams further validated the performance of the developed hardware system. The beam test aim to evaluate the dN/dx-based PID capability and provide references for optimizing the technical design and parameters of the CEPC drift chamber. In addition, the beam test results will be used to guide further optimization of the hardware design.
