부산대학교 도서관

A new type of resistive plate chamber with thin-film electrodes based on diamond-like carbon is under development for background identification in the MEG II experiment. Installed in a low-momentum and high-intensity muon beam, the detector is required to have extremely low mass and a high rate capability. A single-layer prototype detector with 2 cm $\times$ 2 cm size was constructed and evaluated to have a high rate capability of 1 MHz/cm$^2$ low-momentum muons. For a higher rate capability and scalability of the detector size, the electrodes to supply high voltage were segmented at a 1 cm pitch by implementing a conductive pattern on diamond-like carbon. Using the new electrodes, a four-layer prototype detector was constructed and evaluated to have a 46% detection efficiency with only a single layer active at a rate of $\cal O$(10 kHz). The result with the new electrodes is promising to achieve the required detection efficiency of 90% at a rate of 4 MHz/cm$^2$ with all the layers active.
Comment: 5 pages, 8 figures. Contribution to XVI Workshop on Resistive Plate Chambers and Related Detectors (RPC2022), September 26-30 2022. Submitted to Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment