1 / 20

Secondary Emission Ionization Calorimetry Detectors

Secondary Emission Ionization Calorimetry Detectors. David R Winn for Fairfield/Iowa/Mississippi. Secondary Emission Ionization Calorimeters. Secondary Emission: Rad-Hard, Fast Metal-Oxide/Cs Dynodes survive > 500 GigaRad Signal from SE surface(s) in Hadron Showers:

jali
Download Presentation

Secondary Emission Ionization Calorimetry Detectors

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Secondary Emission Ionization Calorimetry Detectors David R Winn for Fairfield/Iowa/Mississippi

  2. Secondary Emission Ionization Calorimeters • Secondary Emission: Rad-Hard, Fast • Metal-Oxide/Cs Dynodes survive > 500 GigaRad • Signal from SE surface(s) in Hadron Showers: • SE yield  Scales with particle momentum ~dE/dx • e-: 3 <  <100, per 0.1 <e-<100 KeV (material depnt) • ~1.05 -1.1 or 0.05-0.1 SE e- per MIP • NB: This is a lower limit on hadron shower SE signals • 4-6 MIP equiv per GeV sampling calorimeters • ~50 SE e- per 100 GeV pi shower w/ MIPs alone • Achtung! SE e- Must be Amplified!

  3. Signal Generation from e, pi Showers Al2O3,TiO2 ~0.05 e- per MIP. Yet used as beam monitors: Rad Hard! Hadron Showers: Sub-mip Charged particles

  4. High SE Yield Materials Peak Yields~5-10+; Alumina Easy MgO Electrons on MgO Diamond SE Yield Stable in air! Diamond Gain 300 V vs B Doping Level

  5. SE Signal: MIP Equivs in Hadron Calorimeter ~5cm Fe Sampling HCal: ~4-6 mip equiv/GeV The Lower Limit on Signal: 100 GeV Fe Hadron Cal: Minimum of 25-50 SE e- …But need amplifier!

  6. Digital Calorimetry: ~12 hits/GeV ->0.5-1 SEe/GeV (CALICE) B.Bilki et al., 2009 JINST 4 P04006

  7. GEANT4: Cu, 1cm plates, 10 GeV e incident Electrons counted as cross 1cm “gap” ->800 SEe/GeV (100 events) Showering e energy

  8. GEANT4 e’s in Cu 1 cm absorber Plates Count shower e crossing gaps Number shower e vs e energy 10 GeV e Implies ~900 e/GeV Crossing gaps. Implies > 45 SEe/GeV ! 100 GeV e

  9. ~740 Charged Particles/GeV More low E than electron -> ~35-80 SEe/GeV

  10. SE MIP Detector w/ 5 x 107 Gain SE e- Already In Vacuum Use Dynodes To Amplify

  11. SE e Detector Option A: Etched Metal Sheet Dynodes Hamamatsu Slat Dynodes up to 6” now. Can be Scaled. • - Chemo-electro machined Metal “Mesh” Dynode Sheets • ~1mm thick dynode layer - scale to 500-200 µm • HV Vacuum: <10KV/mm -> 500V/0.2 mm ok. • Sheets can be up to square meters • Pressure + HV insulators: monotonous insulators • walls, posts, fibers (glass ceramics oxides) • Quasi Channelized: e- confined ->MCP operation • Metal cathode directly D1 • B -> ~2T, as mesh dynode PMT

  12. 5” wide PMT Etched Dynodes

  13. SE e Detector Option B: Metal Screen Dynodes: 15D: g~105, Bz~2 T fine mesh distance between dynodes: 0.9 mm step of the dynode mesh: 13 mm mesh wires diameter: 0.5 mm

  14. SE e Detector Option C: MEMS Mesh Dynodes µMachined Mesh Dynodes Low Cost ~ 30 minute process Channel Width ~200 mm Offset layer layer helical channels Insulator: Si3N4 or SiO2 Confined e- = High B Can be taken to air repeatedly ~ microTorr operation ok

  15. Alternative High-B SE e- Gain Mechanisms: MCP-Like Devices A - El-Mul/A.Breskin Sintered SE MicroSpheres ~20- 100 µm Porous Plate: ~0.5-1 mm thick Gain ~ 106 at 3000 V @ 1G B - Anodic Alumina ~ MCP-like? ~100 nm pores Aspect ratio ~ 50-100:1

  16. Anticipated Performance: SE 12 l Cu Hadron Calorimeter Minimum Signal: muon MIP ~0.1 SE e- per module w/ g > 100,000 (delta rays~SE peak) ~ 40 Samples -> MIP Signal ~ 4 SE electrons/MIP ~ 2 “SE electron”/GeV @ 105/SEe Hadron Shower Signal: Larger SE e per GeV - particles of lower momentum: ->SE ~1.5-6 compared with 1.1-1.05 for MIP. <E> ~ 60 MeV/2cm cube; Calice: ~23 “particles”/Hadron GeV GEANT4 MC: ~740 charged hits/GeV ~35-75 SEe -> 4-75 SEe/GeV hadron calorimeter showers Electron Shower Signal: GEANT4 MC: ~900 SEe/GeV ~45-90 SEe N.B.: e/pi ~ 0.8 - possible compensation

  17. Secondary Emission Calorimeter Sensor Basics: • - Top Metal Cathode, thin film SE inner Surface – Square/Hex/ –can be thick! • - Ceramic (Green Form) Edge Wall; HV feedthrus, supports; ~1cm high • Dynode Stack – mesh, MCP, slats, etc ~5-10 mm • - Bottom Metal Anode – thick/identical to Cathode/Vacuum pump tip; • -

  18. SLHC R&D technology –Secondary Emission Sensor Modules for Calorimeters Schematic SEM Calorimeter Sensor Module - Plate Cathode/Anode Option

  19. SE Calorimeter Manufacture Issues • - Similar to m2 Low Pressure Gas Plasma Display Technology • Proof of Principle/Manufacture - SE Calo sensor far simpler • Hermetic + Voltages similar to dynodes • Vacuum Supported by Ceramic walls or posts • -> thin metal windows Ceramic Body 2.5” MCP-PMT

  20. SE Calorimeter R&D technology Secondary Emission Sensors for Calorimeters • Basic Idea: Dynode/SE Stack is a High Gain Radiation Sensor • High Gain & OK Efficient (MgO yield ~0.1 e/mip per sample) • Energy Resolution: stochastic term ~10-50 SEe/GeV • Compact (micromachined metal ~0.3-1mm thick/stage) • Rad-Hard (PMT dynodes>100 GRads) • Uber-Fast • Potentially low cost/Non-Critical Assy • Simple Al oxide SEM monitors proven at accelerators • Rugged/Could be structural element • Easily integrated into large calorimeters/Arbitrary Shapes • ~Minimal Dead Areas • Minimal services needed. SE Detector Modules Are Applicable to: - Energy-Flow Calorimeters (e+e-, µC, SLHC,….) - Forward HiRad HiRate Calorimeters - Compensation

More Related