Particle identification for a future EIC detector

In its latest Long Range Plan for Nuclear Science Research in the U.S., the Nuclear Science Advisory Committee to the Department of Energy recommended that in regards to new nuclear-physics facilities, the construction of an Electron Ion Collider (EIC) be of the highest priority after the completion of the Facility for Rare Isotope Beams. In order to carry out key aspects of the scientific program of the EIC, the EIC central detector must be capable of hadron particle identification (PID) over a broad momentum range of up to 50 GeV/c. The goal of the EIC-PID consortium is to develop an integrated program for PID at EIC, which employs several different technologies for imaging Cherenkov detectors. Here we discuss the conceptual designs and the expected PID performance of two of these detectors, as well as the newest results of gain evaluation studies of photon sensors that are good candidates to read out these detectors. Development of a gas-aerogel dual-radiator Ring Imaging Cherenkov (dRICH) detector with outward focusing mirrors is being pursued for the hadron endcap. Simulations demonstrate that the dRICH can provide a continuous >= 3 sigma pi/K/p separation from 2.5 GeV/c to 50 GeV/c. A modular aerogel Ring Imaging Cherenkov (mRICH) detector with a Fresnel lens as a focusing element is being pursued for the electron endcap. The design provides for hadron identification over a momentum range of 3 GeV/c-10 GeV/c. The working principle of the mRICH design has been proven in a beam test with a first prototype. The location of the sensor readout planes of the Cherenkov detectors in the magnetic field of the central-detector solenoid, which is expected to be within 1.5 T-3 T, makes is necessary to evaluate the limit of the acceptable performance of commercially available photosensors, such as microchannel-plate photomultipliers (MCP PMTs). Here we present the results of gain evaluation of multi-anode MCP PMTs with a pore size of 10 mu m. Overall, our preliminary results suggest that the 10-mu m pore-size sensors can be operated in a magnetic field with magnitude up to B-max of 2 T. The value of Bmax depends on the relative orientation between the sensor and the field.