Development and demonstration of the Korea ALICE Telescope using electron beams at KEK PF-AR

Abstract

The development of ultra-low-mass, high-precision vertex detectors is a key requirement for future collider experiments and motivates extensive research and development of novel silicon tracking technologies. In this work, we present the development and beam-test demonstration of the Korea ALICE Telescope (KATS), a silicon-tracking telescope designed to support R&D on next-generation cylindrical vertex detectors, such as the proposed ALICE ITS3 upgrade. The telescope consists of six ALPIDE Monolithic Active Pixel Sensors (MAPS) used as reference tracking planes, a bent ALPIDE sensor serving as the device under test, and a scintillating-fiber-based trigger system, all housed in a light-tight modular enclosure. This setup enables precise track reconstruction and detailed performance studies of both planar and curved silicon sensors. Beam tests were carried out using high-energy electron beams at the KEK Photon Factory Advanced Ring (PF-AR). The telescope system operated stably under realistic beam conditions, and its tracking performance was successfully validated. The bent ALPIDE sensor was operated at a bending radius of approximately 18 mm, consistent with ITS3's design goals, without any observable degradation in detection performance. The measured results confirm that the KATS provides a versatile and reliable platform for studies of curved MAPS technologies, alignment precision, and tracking performance. These results provide important experimental validation of key technologies for future low-mass cylindrical silicon vertex detectors and establish KATS as a valuable facility for ongoing and future detector R&D.