1. RPC detection rate capability ≈ 1/ρ Float-Glass (10 12-13 Ω-cm) RPC rate capability < Bakelite(10 10-11 Ω-cm) one. New kind of doped glass was developed by Tsinghua University. It allows to reach much higher rate capabilities.  High-Rate GRPC Glass Specifications: Present max. dimension: 32cm×30cm Bulk resistivity: ≈10 10 .cm Standard thickness: 0.5mm--2mm Thickness uniformity:  0.02mm Dielectric constant: ≈9 Surface roughness: <10nm DC measurement: very stable Scanned image of glass

2. 2 The glass was applied with 1000V for about 32days, integrated charge: 1 C/cm 2  Resistivity decreases with temperature  Resistivity is very stable in DC measurement Current (μA) Bulk resistivity (Ω.cm) Bulk resistivity (10 10 Ω.cm)  High-Rate GRPC Current (μA) A small LR-GRPC was exposed with the CMS, ATLAS RPC to the GIF source for more than one year AA humidity

3.  Single gap PCB support (polycarbonate) PCB (1.2mm)+ASICs(1.7 mm) Mylar layer (50μ) Readout ASIC (Hardroc2, 1.6mm) PCB interconnect Readout pads (1cm x 1cm) Mylar (175μ) Glass fiber frame (≈1.2mm) Cathode glass (1.1mm) + resistive coating Anode glass (0.7mm) + resistive coating Ceramic ball spacer Total thickness: 6.0mm Gas gap(1.5mm) 30X30 cm 2

4. 4 Assembling procedure 6mm(active area) + 5mm(steel) = 11 mm thickness 4.7 mm 4.3mm ASICs : HARDROC2 64 channels Trigger less mode Memory depth : 127 events 3 thresholds Range: 10 fC-15 pC Gain correction  uniformity Electronics readout system R&D Printed Circuit Boards (PCB) with 8-layer structure and buried vias are used DAQ board (DIF) was developed to transmit fast commands and data to/from ASICs.

5. Bean test setup DESY electron beam Beam counter Scint-PM 2 Scint-PM 1 float GRPC+ 4 S-C GRPC GRPC running conditions : Gas flow : 2 l/h Gas mixture: 93% R134A, 5% CO 2, 2% SF 6 Measurements : Efficiency of one chamber is estimated using tracks built from clusters of at least 3 other RPCs. Only one cluster per RPC is allowed for this study Multiplicity : Number of pads associated Tto the track in the given chamber xxxx?

6. Semi-Conductive GRPC performance Threshold@130fC Rate : few Hz/cm 2

7. Semi-Conductive GRPC performance at high rate

8. Time resolution measurement: Single-gap RPC can achieve time resolution better than 1 ns. Much better time resolution can be obtained using multi-gap RPC Semi-conductive multi-gap GRPC can achieve both high rate capability and high time precision measurement.