1. 1 HMPID Project Assembly & Tests of CsI QE monitors: VUV-scanner and ASSET Milestone: December 2002

2. 2 VUV Scanner System for “in-situ” quality control of large area CsI photocathodes (PCs) immediately after the deposition: scanning measurement of the photocurrent produced illuminating PCs with a collimated light beam from a VUV deuterium source;  concept, design, drawings, production: done  assembly & tests: done ASSET ( “A Small Sample Evaporation and Test facility”) R&D setup: Characterization of small samples of CsI films  absolute QE evaluation with a VUV monochromator of resolution of ~4 nm. The monochromator system was designed to be compatible with the UV-system of the VUV- scanner (i.e. allow both UV-systems to be interchangeable): done  assembly and tests: done

3. 3  Layout of the CERN/HMPID CsI deposition plant & VUV scanner  Monitoring: - RGA - Temperatures - Pressures - CsI deposition rates - Witness samples - VUV scanner (rel. QE)

4. 4 Pad cathode mounted on rails Protective box 4 CsI sources (in series) VUV scanner mounted on rails Reference PM Auto CAD drawings:

5. 5 (relative Quantum Efficiency determination) Production/assembly/tests 

6. 6 Turbo pump Primary vac.pump PicoAmmeterMultiplexer D 2 -lamp Optics Before … Now: Inside evaporator  All scanning motions and photo-current readout-electronics are equipped with a remote control (NIDAQ/LabView)

7. 7 VUV Scanner platform inside: Vacuum feed through (4x) Ref.PM & housing Anode ring & Cathode ring & gnd shield PC ‘trolley Rotating Mirror Vertical alignment of Ref.PM and anode Horizontal alignment of mirror and anode

8. 8 Tests, e.g.: - remote control X,Y motion (scan), - PicoAmp.-readout - incident UV-spot scan with photo-diode - 5 0 5 155 150 145 Optical alignment with laser (e.g. red spot)

9. 9 P < 10 -5 mbar 4 interferential filters on rotary disk: relative QE Ref.PM (CsTe) UV source sample holder for 2 samples (18x18mm 2 ) anode grid picoAm.1 picoAm.2 ASSET: A Small Sample Evaporation and Test facility Previous layout/concept: relative QE determination  implicit test for VUV-scanner application: OK evaporation chamber UV test chamber S1S2 UV light spot of   5mm ASSET upgrade with UV-monochromator: absolute QE measurements 

10. 10 UV-mirror Sample holder input Argon output Argon MgF 2 lens & x-y micro-control lens holder diaphragm anode grid Ref PM UV test chamber Deuterium lamp with quartz exit-window Upgrade concept & design (compatible with VUVscanner optics) monochromator box (leak- & light-tight)

11. 11 System test: Deuterium Lamp spectrum D 2 -peak at =160 nm is being cut off by the quartz exit window of the D 2 -lamp I [pA] [nm] Upgraded setup is ready