1. EDMS No. 888499 Photoinjector General + Photocathodes presented by Konrad Elsener (CERN-AB)

2. EDMS No. 888499 Acknowledgements (PHIN) We acknowledge the support of the European Community- Research Infrastructure Activity under the FP6 “Structuring the European Research Area” programme (CARE, contract number RII3-CT-2003-506395).

3. EDMS No. 888499 Outline Overview Photocathodes: Status + Outlook (photocathode for CLEX) PHIN in CTF2 Summary

4. EDMS No. 888499 Overview LASER RF GUN RF equip. Photocathode “Photoinjector” bunched electron beam Cs2Te UV …cf. next two talks… G. McMonagle (yesterday)

5. EDMS No. 888499 Photocathodes cf. presentation by R. Losito, 17 Jan. 2007 HIGHLIGHT end of 2006: Photocathode No. 166 produced (after > 3 years interruption) Cs-Te cathode, co-evaporation, Quantum Efficiency > 6% very detailed description of No. 166: CTF3-Note-089 many thanks to Eric Chevallay

6. EDMS No. 888499 Photocathodes – No. 167 HIGHLIGHT 2007: Photocathode No. 167 produced 29 November (Cs-Te cathode, co-evaporation) Quantum Efficiency Lifetime measured during 1000 hours

7. EDMS No. 888499 data taken in DC-gun, 80 kV (-> 8 MV/m) 29 Nov. 2007 Xmas break 9 Jan. 2008 CTF3 specs (drive beam) Photocathodes - No. 167

8. EDMS No. 888499 manipulator DC- gun preparation chamber transport carrier ~ 1.4 m Photocathodes – No. 167

9. EDMS No. 888499 basic unit: Cu “plug” on the “arm” inside the transport carrier: up to 4 plugs Photocathodes - No. 167

10. EDMS No. 888499 Photocathodes Process Control and Reproducibility (A. Barbiero and E. Chevallay) - cleanliness / UHV vacuum

11. EDMS No. 888499 H2H2 CO N 2 N CH 4 O H 2 O... a long period of improvements, pumping, leak testing, baking-out, leak testing, repair, pumping, baking out,... vacuum before cathode preparation: < 3x10 -11 mbar residual gas analysis in preparation chamber (29 Nov. 2007) Photocathodes - vacuum

12. EDMS No. 888499 Photocathodes – film thickness Process Control and Reproducibility (A. Barbiero and E. Chevallay) - cleanliness / UHV vacuum - film thickness monitoring (Te, not Cs) -> new stylus profilometer, calibrated

13. EDMS No. 888499 Photocathodes - film thickness Te films on quartz substrate new Stylus Profilometer

14. EDMS No. 888499 Photocathodes – film thickness cross-check of Stylus Profiler using a calibrated sample* (Rank Taylor Hobson) with 3 grooves, 24 nm each solid lines:  =24 nm dashed line:  =26 nm Result: Profilometer intrinsic error < 2 nm * sample on loan from CERN-TS/MME (W. Vollenberg) 0.5 mm

15. EDMS No. 888499 Photocathodes – transfer arm Process Control and Reproducibility (A. Barbiero and E. Chevallay) - cleanliness / UHV vacuum - film thickness monitoring -> stylus profilometer, calibrated - possibility of cathode chemical analysis (X-ray Photoel. Spectr.) -> new, smaller transfer arm (for 1 plug) (collaboration with team of M. Taborelli / TS-MME)

16. EDMS No. 888499 Photocathodes – transfer arm (attached to preparation chamber) (courtesy A. Barbiero)

17. EDMS No. 888499 Photocathodes – plug surfaces Process Control and Reproducibility (A. Barbiero and E. Chevallay) - cleanliness / UHV vacuum - film thickness monitoring -> stylus profilometer, calibrated - possibility of cathode chemical analysis (XPS) -> new transfer arm - reproducible “plug” surface -> test programme on surface preparation + analysis (work in progress - No. 166 and No. 167 are very different)

18. EDMS No. 888499 photocathode for CLEX Preparation chamber for CLEX (ex-CTF2 Probe-Beam) Cs + Te sources (no co-evaporation); 1 quartz thickness monitor (DN 100 flange) manipulator arm (position for “plug”) pumping port

19. EDMS No. 888499 “CTF2” (south) photoemission laboratory “CTF2”

20. EDMS No. 888499 “CTF2” - status

21. EDMS No. 888499 Acknowledgments Nathalie Lebas: expert help with the laser Arnaud Brielmann: expert help with controls and interlocks (for equipment safety)

22. EDMS No. 888499 Summary + Outlook Photoemission Laboratory: ready for production of cathodes Cs-Te cathode No. 167: ready for PHIN work in progress to improve reproducibility near future: CLEX cathode continue contributions to PHIN in “CTF2”

23. EDMS No. 888499 spare slides

24. EDMS No. 888499 spare slides 8 Nov. 2007

25. EDMS No. 888499

26. PHIN overview