esign and test for the CEPC muon subdetector based on extruded scintillator and SiPM

combination of scintillator, wavelength shifting (WLS) fiber, and silicon photomultiplier (SiPM) shows an excellent performance in the `KL and  detector (KLM)' of the Belle II experiment. In this study, we present the R&D efforts for a similar detection technology utilizing a new scintillator and SiPM. This technology can be applied to a muon detector for the proposed CEPC experiment. The R&D encompasses the investigation of the performance of a new 150 cm-long scintillator, the NDL SiPM with a sensitive surface of 3 mm  3 mm, or the Hamamatsu MPPC with a sensitive surface of 1.3 mm  1.3 mm. Additionally, it includes the construction of a detector strip and the methods employed to achieve excellent light collection. Cosmic ray tests reveal efficient photon collections by NDL SiPM or MPPC, with efficiencies well above 90% using a threshold of 8 p.e.. The time resolutions for hits at the far end of a scintillator strip are better than 1.7 ns. The observed performance indicates a promising option for an outstanding muon detector for CEPC.