Hi’Beam-S: A Monolithic Silicon Pixel Sensor-Based Prototype Particle Tracking System for HIAF

Particle tracking systems, which function either as particle detectors or beam monitors, are the critical elements for the high-intensity heavy-ion accelerator facility (HIAF) complex. The novel Topmetal-M pixel sensor, which combines the features of both monolithic active pixel sensor (MAPS) and the Topmetal sensor, can be used either for a pixel detector or a nondestructive beam monitor. The Topmetal got its name as some part of the pixel’s top metal layer is exposed to sense the drifting charge. In this article, a prototype particle tracking system, named Hi’Beam-S, has been designed to characterize the Topmetal-M sensor. The laser test shows a spatial resolution of
$\sim 9 ~\mu \text{m}$
for the laser spot measurement. The heavy-ion beam test demonstrates that, for a 5-mm track with a ~20° incident angle, a spatial resolution of
$\sim 1.59 ~\mu \text{m}$
could be achieved.