Minimal material, maximum coverage: Silicon Tracking System for high-occupancy conditions

Silicon strip sensors have long been a reliable technology for particle detection. Here, we push the limits of silicon tracking detectors by targeting an unprecedentedly low material budget of 2%–7% X0 in an 8-layer 4 m2 detector designed for high-occupancy environments (≤ 10 MHz/cm2). To achieve this, we employ Double-Sided Double Metal (DSDM) silicon microstrip sensors, coupled with readout electronics capable of precise timing and energy measurements. These 320μm thick sensors, featuring 2 × 1024 channels with a 58μm pitch, are connected via ultra-lightweight aluminum-polyimide microcables for signal transmission and integrated with a custom SMX readout ASIC, operating in free-streaming mode. This system enables the simultaneous measurement of time (Δt≃5ns) and charge deposition (0.1–100 fC), significantly enhancing the detector’s capacity for high-precision track reconstruction in high-occupancy and harsh radiation field environments. The primary application of this technology is the Silicon Tracking System (STS) for the CBM experiment, with additional potential in projects like the J-PARC E16 experiment and future uses in medical physics, such as advanced imaging telescopes. In this contribution, we present the current status of CBM STS construction, with almost one-third of the modules produced and tested. We also discuss immediate applications and explore promising prospects in both scientific and medical fields.