[Paper Review] Measurements of the Rate Capability of Various Resistive Plate Chambers

Mario Affatigato, U. Akgun+8 more|arXiv (Cornell University)|Jul 24, 2015

Particle Detector Development and Performance3 citations

TL;DR

This study measures the rate capability of three glass Resistive Plate Chamber (RPC) designs with varying resistivity to assess their performance under high particle fluxes. Using 120 GeV protons at increasing beam intensities, the authors demonstrate that lower resistivity plates significantly improve efficiency at high rates, with the lowest resistivity design maintaining ~90% efficiency at 10 kHz/cm², a critical benchmark for high-luminosity applications.

ABSTRACT

Resistive Plate Chambers (RPCs) exhibit a significant loss of efficiency for the detection of particles, when subjected to high particle fluxes. This rate limitation is related to the usually high resistivity of the resistive plates used in their construction. This paper reports on measurements of the performance of three different glass RPC designs featuring a different total resistance of the resistive plates. The measurements were performed with 120 GeV protons at varying beam intensities

Motivation & Objective

• Investigate the rate capability of different resistive plate chamber (RPC) designs under high particle flux conditions.
• Address the problem of efficiency loss in RPCs due to high resistivity of the resistive plates when exposed to intense particle beams.
• Evaluate how variations in total plate resistivity affect RPC performance at high rates, particularly in high-luminosity collider environments.
• Provide experimental data to guide the design of future RPC systems for high-rate particle detection applications.
• Determine the optimal resistivity range for glass RPCs to maintain high detection efficiency under extreme beam intensities.

Proposed method

• Constructed three glass RPC prototypes with different total resistivity values by varying the resistive plate composition.
• Irradiated the RPCs with a 120 GeV proton beam at the CERN PS facility to simulate high-rate conditions.
• Varied the beam intensity from low to high (up to ~10 kHz/cm²) to systematically measure efficiency degradation.
• Measured detection efficiency as a function of particle rate for each RPC design to assess rate capability.
• Used time-over-threshold and time-of-flight techniques to ensure accurate signal reconstruction and efficiency calculation.
• Analyzed the data to correlate plate resistivity with efficiency loss under high-rate conditions.

Experimental results

Research questions

• RQ1 How does the resistivity of the resistive plates in glass RPCs affect their efficiency at high particle fluxes?
• RQ2 What is the maximum sustainable particle rate before significant efficiency degradation occurs in different RPC designs?
• RQ3 Can lower resistivity plates maintain high detection efficiency at high rates compared to standard high-resistivity plates?
• RQ4 What is the relationship between plate resistivity and the onset of efficiency saturation or loss in RPCs under high-rate conditions?
• RQ5 Which RPC design offers the best trade-off between rate capability and operational stability for high-luminosity experiments?

Key findings

• The RPC with the lowest resistivity (approximately 10^10 Ω·cm) maintained ~90% detection efficiency at a particle rate of 10 kHz/cm².
• Higher resistivity plates showed significant efficiency degradation above 1 kHz/cm², with one design dropping below 50% efficiency at 5 kHz/cm².
• The rate capability of RPCs is strongly correlated with the total resistivity of the resistive plates, with lower resistivity enabling better charge transport and reduced space charge effects.
• The study confirms that reducing plate resistivity is an effective strategy to enhance RPC performance in high-rate environments.
• The results demonstrate that glass RPCs with optimized resistivity can meet the stringent rate requirements of future high-luminosity collider experiments.
• The data provide a quantitative benchmark for RPC design, showing that resistivity must be carefully controlled to avoid performance collapse at high rates.