Beam test results of the prototype of the multi wire drift chamber for the CSR external-target experiment

TL;DR

This paper reports on the testing of a prototype multi wire drift chamber designed for the CSR external-target experiment, demonstrating high efficiency and acceptable tracking precision in heavy ion collision conditions.

Contribution

The paper presents the design, assembly, and test results of a half-size MWDC prototype with multi-directional sense wires for the CSR experiment, showing it meets performance requirements.

Findings

Layer efficiency exceeds 95%.

Tracking residual is approximately 301 micrometers.

Performance meets experimental requirements.

Abstract

The half-size prototype of the multi wire drift chamber (MWDC) for the cooling storage ring (CSR) external-target experiment (CEE) was assembled and tested in 350 MeV/u Kr+Fe reactions on the heavy ion research facility in Lanzhou (HIRFL). The prototype consists of 6 sense layers, where the sense wires are stretched in three directions X, U and V, meeting $0^\circ$, $30^\circ$ and $-30^\circ$ with respect to the vertical axis, respectively. The sensitive area of the prototype is $76 {\rm cm} \times 76 {\rm cm}$. The amplified and shaped signals from the anode wires are digitized in a serial capacity array. Being operated with 1500 V high voltage on the anode wires, the efficiency for each layer is beyond 95\%. The tracking residual is about $301 \pm 2 \rm \mu m$. The performance meets the requirements of CEE.