1. Photon-Absorption Enhancement Factor Work supported by National Nuclear Security Administration (NNSA), Office of Nonproliferation Research and Engineering, DOE, and two Advanced Detector Awards, Office of Science, DOE Daniel Ferenc, Andrew Chang Eckart Lorenz Physics Department, University of California Davis, Max Planck Insitute, Munich

2. existing 3 existing mass-production technologies ENCLOSURE: FLAT-PANEL TV ELECTRON DETECTION: SEMICONDUCTOR Scintillator + Geiger-MODE AVALANCHE DIODE ‘Light Amplifier’ PHOTON  ELECTRON CONVERSION: CLASSICAL PHOTOCATHODE

3. existing 3 existing mass-production technologies ENCLOSURE: FLAT-PANEL TV ELECTRON DETECTION: SEMICONDUCTOR Scintillator + Geiger-MODE AVALANCHE DIODE ‘Light Amplifier’ PHOTON  ELECTRON CONVERSION: CLASSICAL PHOTOCATHODE ALREADY VERY GOOD MAJOR MODIFICATIONS (will show tomorrow)

4. existing 3 existing mass-production technologies ENCLOSURE: FLAT-PANEL TV ELECTRON DETECTION: SEMICONDUCTOR Scintillator + Geiger-MODE AVALANCHE DIODE ‘Light Amplifier’ PHOTON  ELECTRON CONVERSION: CLASSICAL PHOTOCATHODE ALREADY VERY GOOD MAJOR MODIFICATIONS (will show tomorrow) LOOKIN FORWARD FOR IMPROVEMENTS

5. DIAGNOSTIC TOOL – NOT USED (YET)

7. 7-pixel 5-inch ReFerence Flat-Panel Prototype UHV Transfer System : Photocathode deposition Indium/Au/Cr deposition Vacuum sealing

8. Lasers for Active Mirror Control

9. SUPER-EFFICIENT CAMERA

11. PMT Maximizing Double-Hits in a PMT Not yet optimized for the milky PMT coating  Significant additional improvements to come

14. Vacuum Photocathode Glass Window Photo-Electron Photon Photon Absorption (Electron ‘Creation’) e.g. in S-20 40% ph. (400 nm) are absorbed in a 30 nm thick photocathode Probability for an electron to reach the vacuum surface Random Walk - mainly electron-imperfection scattering (less e-e and e-phonon) e.g. scattering length in S-20 ~25 nm Therefore: QE ~ 10-20%

15. Vacuum Photocathode Photon Photon Absorption (Electron Creation) Probability for an Electron to Reach the Vacuum Surface (Random Walk) Photo-Electron (e.g. Substrate, Reflector,…) & LOWER PRODUCTION COST !

16. Vacuum Photocathode UV Photon UV Photon Absorption (Electron Creation) Mostly @ Surface Probability for an Electron to Reach the Vacuum Surface (Random Walk) Photo-Electron Thin Photocathode on a Reflector, Interference, Multi- layer Systems Westinghouse, RCA, ITT ~1963-1975

17. Quantum Efficiency Wavelength Reflection Mode vs. Transmission Mode Extension into “blue & UV” ~30-43 % QE bialkali ~190-450 nm (Hamamatsu side-on PMT R7517 )

20. TRANSMISSION PC REFLECTION PC Source: Silvano Donati, Phosotosensors

23. REFLECTION-MODE PHOTOCATHODES GOOD - air WORSE – dense media for larger incidence angles H2O AIR Water Cheenkov – neutrinos etc. Liquid scintillator Plastic, crystal scintillator Gamma-ray astronmy – Atmospheric Cherenkov Telescopes

24. & Mass production High performance Mr. Mrs.