Download presentation
Presentation is loading. Please wait.
Published byClement Blankenship Modified over 8 years ago
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
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.