Performance of a Quintuple-GEM Based RICH Detector Prototype

TL;DR

This paper reports on a successful test of a compact quintuple-GEM based RICH detector using CF4 gas, capable of high photoelectron yield for particle identification at high momenta relevant to the Electron Ion Collider.

Contribution

It introduces a novel quintuple-GEM RICH detector with focusing capabilities and low index gas, demonstrating its viability for high-momentum particle identification in collider experiments.

Findings

Achieved over 10 photoelectrons per ring with a 1-meter radiator

Demonstrated effective particle identification up to 50 GeV/c

Validated the detector's performance for forward region applications

Abstract

Cerenkov technology is often the optimal choice for particle identification in high energy particle collision applications. Typically, the most challenging regime is at high pseudorapidity (forward) where particle identification must perform well at high high laboratory momenta. For the upcoming Electron Ion Collider (EIC), the physics goals require hadron ($\pi$, K, p) identification up to $\sim$~50 GeV/c. In this region Cerenkov Ring-Imaging is the most viable solution.\newline The speed of light in a radiator medium is inversely proportional to the refractive index. Hence, for PID reaching out to high momenta a small index of refraction is required. Unfortunately, the lowest indices of refraction also result in the lowest light yield ($\frac{dN_\gamma}{dx} \propto \sin^2{\left(\theta_C \right)}$) driving up the radiator length and thereby the overall detector cost. In this paper we report on a successful test of a compact RICH detector (1 meter radiator) capable of delivering in excess of 10 photoelectrons per ring with a low index radiator gas ($CF_4$). The detector concept is a natural extension of the PHENIX HBD detector achieved by adding focusing capability at low wavelength and adequate gain for high efficiency detection of single-electron induced avalanches. Our results indicate that this technology is indeed a viable choice in the forward direction of the EIC. The setup and results are described within.