1. Medium and High Energy Photons for Nuclear Particle Physics Schin Daté Accelerator Division, SPring-8/JASRI Advanced Photons and Science Evolution 2010 June 14-18, 2010, Osaka Japan

2. Previous talks which includes laser backscattering  beamlines T. Shima: New Subaru Y. Ohashi: LEPS/LEPS2 W. Tornow: HI  S W.C. Chang: LEPS M. Niiyama: LEPS/LEPS2

3. My talk: I. High Energy  Production in SPring-8 II. Intense 10 MeV  Production in Light Sources Additional options to future backscattering  beamlines

4. Production of high energy gamma rays

5. HELP production by X-ray re-injection

6. multilayer mirror

7. Choice of Undulator Portion of the fundamental= kG

8. Yield of X-ray photons  d ˙ N ph d  /I e ( )

9. Re-focussing Thin undulator approximation e-e- 275x2  m 6x2  m ~100  rad Can s be mm 2 ? In principle, yes. spherical mirror

10. Bunch mode dominance... 100  rad 60 cm h ~ 275  m e-e- v ~ 6  m

11. Yield of High Energy Gamma Notation:, Undulator (K=5~6,  =1.1 m,  4 periods) : reinjection efficiency for Electron beam emittance + re-focussing Beam current: 100 mA/e =.,. 50%

12. Summry of part I Provided  an undulator with  high reflectable (R > 0.5)spherical mirror for 100 eV photons  with timing adjustment system (mirror position z = 24 +- 2 m, dz = 6mm) We may obtain in principle. The number may increase by an order of magnitude for the future refinement of the storage ring.

13. Intense 10 MeV  Production in Light Sources II

14. Well known facts about Compton back scattering Controlled Polarization(3) ~ flat (1) Energy, Angle(2), = 0.5 b I = 100 mA l = 10 m for Yield(4)

15. Progress in laser technology Heat load limit ~ 20 MW / mm  100 kW output is cleared in this way bundled fiber line of, say, cm  is possible to make Fiber Laser Single mode CW output power (W) year  15  m core Yb fiber laser (IPG): 1030 ~ 1050 nmCW single mode 2 kW multimode 20 kW Polarization?

16. Eg_max for CO2

17. 2. Production of Intense 10 MeV  Rays (1)Enegy aperture Spring-8CLSDFELLMAX-IVNSLS-II 8 2.90.24-1.2 3 3 2436 285 64 96 1320 16 0.876 42 keV 0.712 0.816 4/3 2.74 17.1 1.7 4.04 154 45 19 @ 500 MeV 30 @ 1.2 GeV 91

18. (2) Longitudinal beam quality = I = 100 mA Spring-8CLSDFELLMAX-IVNSLS-II 4.80.57 0.36 0.96 2.6 4.21.94.3 4 9.7 No serious effect on the longitudinal beam quality

19. Summary of Part II There is no crucial problem to producee very intense (~ 10^11 /s) 10 MeV gamma rays in 3 GeV light sources including CLS, MAX IV and NSLS-II.. There are technologies available to realize the intense gamma production. Now is the adequate time to consider such a possibility seriously.

20. Conclusion I. We may think seriously about quasi-monochromatic g beamline with Eg_max ~ Ee and Ng ~ 10^6 /s as an option to future beamlines in high energy synchrotron light sources. II. There is no crucial problem to producee very intense (~ 10^11 /s) 10 MeV gamma rays in new 3 GeV light sources.

21. -------- Backup --------

22. reinjection schemes

23. Why Do We Want 10^11 /s Photons?  = 10 g / cm^3 Because many interesting elementary interactions occur with  ~ pb l = 1 cm  = 1 pb for

24. Old proposal

25. Optical param bl33

26. optical parameters

27.  beam divergence BCS ~ 64  rad  beam divergence in LSS BL is dominated by Compton scattering. xx =3.4 10 -9 radm yy xx,=0.2 % () <= 33LEPLSS [  rad] 5823 [  rad] 1.81.2 [mm] 0.340.30 [  m] 12 Contributions are wighted for Gaussian laser beam. Values are valid for the laser waist radius > 0.5 mm.

28. Angular Distribution

29. Polarization

30. Energy