2. Scoping study for a future accelerator neutrino complex Blackett Laboratory - Imperial College - London Discussion meeting 6-7 May 2005 Photo-detectors R&D for Megaton-scale Detectors L. Mosca CEA-Saclay

3. Envisaged Megaton-scale detectors : Water Cherenkov LiAr TPC Liquid scintillators …………

6. Tunnel actuel Futur Tunnel de Service Laboratoire actuel Futur Laboratoire

8. Photo-detectors R&D for Megaton-scale Detectors (Water Cherenkov, LiAr TPC, Liquid scintillator, …) A) Vacuum photo-tubes : - “standard” (with dynodes) PMTs - “hybrid” (with PIN or APD diodes) HPD - “wall-papers” (Ferenc) B) Gaseous photo-tubes, “wall-papers” shaped : - with CsI photo-cathode (ultra-violet region) - with bi-alcali photo-cathode (visible region)

9. Joël PouthasIPN Orsay Photocathode PMTHPMTHPDHAPD Medium SER and TTS (depend of size) HV 2 or 3 kV Photocathode PIN Photocathode APD Photocathode Scint PMT Very good SER TTS ? (depend of FEE) HV (negative) 15 to 30 kV Very good SER and TTS (depend of FEE) HV (negative) 10 kV or more Good SER and TTS (depend of scint) HV 20 to 30 kV Electronics Bulb shape photodetectors

10. Joël PouthasIPN Orsay Companies ETL PHOTONIS + Labs (Characterization) Quasar (Russia) R&D VLVvT R&D PHOTONIS (+ IPNO) R&D Hamamatsu and Tokyo Univ. R&D HPD CERN R&D PHOTONIS DEP PMTHPMTHPDHAPD Photocathode Scint PMT Photocathode PIN Photocathode APD Bulb shape photodetectors

11. 13 inch HAPD prototype ( HV = 12 kV ) Hamamatsu+Tokyo Univ.

12. “WALL PAPERS” (FLAT PANELS) with VACUUM Detectors (Ferenc)

14. “WALL PAPERS” (FLAT PANELS) with GASEOUS Detectors (MICROMEGAS)

15. Conversion/drift (1kV/cm) Amplification (40 kV/cm) micromesh insulator strips (3mm) (100  m) Drift electrode

16. MICROMEGAS PHOTODETECTOR Photon feed back suppressed Negligible Ionization Excellent single electron response

20. Other people/laboratories also potentially interested in this development : Fanourakis gfan@mail.demokritos.grgfan@mail.demokritos.gr Busto busto@cppm.in2p3.frbusto@cppm.in2p3.fr Alexander S.Murphy amurphy@ph.ed.ac.ukamurphy@ph.ed.ac.uk Smith.N n.j.t.smith@rl.ac.ukn.j.t.smith@rl.ac.uk Spooner n.spooner@sheffield.ac. ukn.spooner@sheffield.ac. uk Vavra

21. Conclusion/Outlook To go from a I3-Neutrino scheme to a Design Study proposal, we need to be more ambitious and try to fulfil all the “objectives”, including the detection in the visible range and the optimisation of the prototypes in view of a very massive production.