Production of Vessel and Mirrors for the pfRICH Detector at the Electron-Ion-Collider

Stony Brook University (CFNS)CPAD Production of Vessel and Mirrors for the pfRICH Detector at the Electron-Ion-Collider C-J. Naïm Coordinating Panel on Advanced Detectors (CPAD) October, 9, 2025 Stony Brook University (CFNS)CPAD 1 •A compact central detector with several subsystems" •Hermetic coverage: –3.5 < η < 3.5 (tracking, calorimetry, particle identification) p/A e pfRICH subsystem in backward region The ePIC detector at the EIC Stony Brook University (CFNS)CPAD 2 Physics Motivations at the EIC e− h •Semi-Inclusive Deep Inelastic Scattering •Production of hadrons in final-state" •Provide information on: " the fragmentation process (hadronization) the hadronic structure → → p/A Particle Identification detectors are crucial Stony Brook University (CFNS)CPAD 3 p K π The pfRICH Concept e− p/A θc∼θ2 sat − m2 p2 θc Particle Identification •Charged particle → emits Cherenkov photons at angle •Photons project onto photodetectors → form a ring Ring radius •Measuring ring size → deduce → particle mass θc → ∝tan θc θc Detection Principle The pfRICH will provide > 3σ π/K separations for momentum up to 7 GeV/c for –3.5 < η < -1.5 Stony Brook University (CFNS)CPAD 4 The pfRICH Design Summary Aerogel •Three radial bands •Opaque dividers •2.5 cm thick, 42 tiles total Vessel • Lightweight structure • Reinforced carbon fiber and 3D printed materials • Filled with nitrogen HRPPD photosensors • 120 mm size • Tiled with a 3.0 mm gap • 68 sensors total Mirrors •Cylindrical and conical geometries •Large acceptance •High reflectivity Stony Brook University (CFNS)CPAD 5 pfRICH An International Task Force Stony Brook University (CFNS)CPAD 6 Vessel Components and Fabrication Vessel consists of • Cylindrical body (Stony Brook) Carbon-fiber sandwich structure → lightweight, gasand light-tight • Reinforcing end-rings (Purdue) Machined carbon-fiber end-rings → stability & sensor/aerogel mounting • Sensor plane (Purdue) • Aerogel wall (Purdue) Objective: build a cylindrical vessel Vessel End-rings Sensor Stony Brook University (CFNS)CPAD 7 Mandrel Assembly for the Vessel Stony Brook University (CFNS)CPAD 8 Mandrel Machining for the Vessel Foam Machining System •Cutting uses a lathe-like setup with a rotating bit, driven by 3 motors" Milling - Linear - Rotary motors " 1. End mill mounted on a motorized micrometer stage → precise depth control 2. Lead screw motor moves the stage horizontally" 3. Mandrel motor rotates the foam Stony Brook University (CFNS)CPAD 16 pfRICH Mirror Reflectivity Cutoff by acrylic filter below 300 nm Coating mixture (sample) •28: Cr = 4.033 kA ; Al = 17.058 kA •47: Cr = 5.006 kA ; Al = 20.009 kA •48: Cr = 1.997 kA ; Al = 8.048 kA Curved mirror development still ongoing → Capability to reach 90% reflectivity Objective: Mirrors with high reflectivity ( 90% over 300–600 nm) ∼ Stony Brook University (CFNS)CPAD 17 Conclusion • Hadron ID is crucial for many EIC physics goals → provided in electron-going direction by pfRICH • Carbon-fiber vessel minimizes material budget → first engineering prototype completed • Mirror development with high reflectivity underway at SBU p e− p/A K π