Centre of Excellence
- MSMGRPC based on commercial float glass (rglass ~ 1012Wcm) keeps the performances up to ~1 kHz/cm2 ; this type of RPC could be a
     solution for a major part of the CBM - TOF subdetector.
- CBM - TOF subdetector at small polar angles - high counting rate environment (up to 20 kHz/cm2).
- Solutions:
          - Electrodes with lower resistivity
          - Smaller and many gaps
- Our prototypes were built using Pestov glass with
r ~1010 Wcm.
RPC Counting Rate Performance
The RPC prototypes based on PESTOV glass with a resistivity of ~1010Wcm were tested in-beam in March 2008 @ the ELBE facility at Forschungszentrum Dresden-Rossendorf
HCRRPC prototypes
Differential Strip - Readout Pestov Glass RPC
- excellent time resolution
- high granularity (multihit performance to be checked in real conditions)
- preliminary 85% efficiency, not yet at the plateau value (the influence of NINO gain, threshold and electric field distribution to be studied!)
- counting rate performance under investigation
- identical architecture using low resistivity glass electrodes - MUST!
First results from in-Beam Tests @ SIS, GSI- Darmstadt
Differential Strip - High granularity HCRRPC
Presented results from in-beam tests @CERN & the results of the in-beam tests @ COSY
First version - RPC5:
- strip structure high voltage electrodes for both polarities
Second version - RPC3:
- strip structure high voltage electrodes for both polarities in contact with a resistive layer
Third version - RPC4:
      - strip structure high voltage electrodes for both polarities Chinese glass
High granularity, symmetric, differential strip readout RPC
- a detection efficiency better than 97%
- a cluster size of 3 - 3.1 strips @ 2.1 kV/gap
- a time resolution better than 55 ps
- a position resolution along the strip of ~ 4.5 mm
- the obtained efficiency and cluster size are a bit lower for the RPC5 (2x 7 gaps, strip HV electrodes) prototype
- the time resolution is systematically better for the gas mixtures based on iso-butane