Summary of GEM DHCAL Developments Andy White CALICE
- Slides: 6
Summary of GEM DHCAL Developments Andy White CALICE, Shinshu U. March 2012
GEM DHCAL Developments - Series of chambers built and tested using 3 M and CERN foils (10 cm x 10 cm, 30 cm x 30 cm, …) - Cosmic ray and source tests – to establish construction techniques and operating characteristics: - gas composition - HV for ionization, transfer, and signal induction regions - stability - signal characteristics - MIP signal size - noise characteristics (usingle channel chip set and various KPi. X versions)
GEM DHCAL Developments Readout: - Need high-density chips for large areas - Analog – worked with SLAC on KPi. X development and testing – allowed determination of: - Ionization spectrum - Variation of spectrum with HV - Noise spectrum - Further KPi. X tests dependent on production of large area anode boards with installed KPi. X chips. - Digital – used DCAL from Argonne as used for RPC’s - will allow use in RPC + GEM stack
GEM DHCAL Developments Beam tests: - series of chambers exposed to muon, proton and pion beams at Fermilab - preliminary results on: - hits vs efficiency - nhits for single particles and showers - uniformity across chambers - analyses ongoing. - further beam tests (at SLAC for synchronous KPi. X) planned for 1 m x 33 cm chambers
GEM DHCAL Developments Next steps: (depending on continued LC detector R&D support in U. S. ) - Assemble and test first 1 m x 33 cm double-GEM chamber (clean room set up at UTA for large chamber assembly) - Develop mechanics for 1 m 2 chambers - Characterize 1 m 2 plane(s) with cosmics and beams - Use 1 m 2 planes in stack - Develop GEM-DHCAL module design, fabrication, services, barrel/end-cap chambers, … - Cost estimate for GEM-DHCAL We will continue to develop the GEM DHCAL option as funds allow.
GEM DHCAL Summary Established performance - MIP signal size, noise measurement, hits vs. efficiency, gain vs. HV Validated simulation - Early studies of hits vs. energy for single particles - Full simulation of double-GEM layer yet to be done Operational experience - Many 30 cm x 30 cm double-GEM layers tested - Chambers operated with KPi. X and DCAL readouts (extensive KPi. X testing) - Stability over weeks of operation for cosmics, two week periods in beam - Exposure to muon, pion and proton beams and pion showers Scalable technology solutions - Large area GEM chambers exist - 1 m x 33 m foils made by CERN -> chambers under construction Open R&D issues - Operation of large area (1 m x 33 cm) chambers - Integration and operation of 1 m 2 layers in calorimeter stack - Design of technical prototype layer
