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Possibility of bright, polarized high energy photon sources at the Advanced Photon Source. Yuelin Li Advanced Photon Source, Argonne National Laboratory. Outline. Introduction: Existing g -ray facilities APS overview Why APS g -ray? Compton scattering basics
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Possibility of bright, polarized high energy photon sources at the Advanced Photon Source Yuelin Li Advanced Photon Source, Argonne National Laboratory Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
Outline • Introduction: Existing g-ray facilities • APS overview • Why APS g-ray? • Compton scattering basics • Possible performance of the APS g-ray facility • Booster • Storage ring • Laser systems • Summary Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
Outline • Introduction: Existing g-ray facilities • APS overview • Why APS g-ray? • Compton scattering basics • Possible performance of APS g-ray facility • Booster • Storage ring • Laser systems • Summary Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
Existing g-ray facilities GRAAL 3106/s @ 1.5 GeV Why LEGS 5106/s @ 0.5 GeV ROKK 3106/s @ 1.6 GeV 2106/s @ 1.5 GeV LEPS 5106/s @ 2.4 GeV HIGS 108/s @ 0.2 GeV Only sun shine. Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
APS overview 1 Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
APS overview 2 Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
APS overview 3 Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
Booster Stores .4-4 GeV beam 20 m APS booster storage ring Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
APS SR Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
Outline • Introduction: Existing g-ray facilities • APS overview • Why APS g-ray? • Compton scattering basics • Possible performance of APS g-ray facility • Booster • Storage ring • Laser systems • Summary Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
APS parameters Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
APS: Top-up operation 2-3 nC/2 min 108 e-/s Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
Outline • Introduction: Existing g-ray facilities • APS overview • Why APS g-ray? • Compton scattering basics • Possible performance of APS g-ray facility • Booster • Storage ring • Laser systems • Summary Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
Es,h/l gmc2, gmv q EL,h/l gmc2, gmv Compton scattering basics a=1/(1+x) Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
w0 w0=2s0 Photon flux calculation Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
Photon flux and bunch lifetime Photons per scattering Flux Lifetime Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
Booster: Intrabeam scattering Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
Outline • Introduction: Existing g-ray facilities • APS overview • Why APS g-ray? • Compton scattering basics • Possible performance of APS g-ray facility • Booster • Storage ring • Laser systems • Summary Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
Booster limit, 1 GeV SR limit, 2.8 GeV Performance: energy, polarization Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
Flux and life time: Booster Coherent Reg A9000, 2.5 W, 250 kHz @ 800 nm 5 nC charge Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
Reality and Future: booster Currently working charge: 2-3 nC Highest ever achieved: 4-5 nC Off-the-shelf laser: 2.5 W Immediately available: 1108 @ 0.1 GeV 2106 @ 1 GeV Repetition rate: 200 photons in 0.1 ns at 815 kHz To get to higher fluxes * Need to up grade rf tuner to compensate large beam loading at higher charge * Replace the magnets for better beam quality * More powerful laser/intracavity scattering, 10 times or more Foreseeable: 1109 @ 0.1 GeV 2107 @ 1 GeV Repetition rate: 2000 photons in 0.1 ns at 815 kHz Machine Limit: 1011 Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
Flux and lifetime: SR Injection limit Spectra Physics Tsunami, 3.5 W, 80 MHz @ 800 nm Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
Reality and Future: SR Currently injection charge: 2-3 nC/2 min 1-1.5×108 e-/s loss Highest ever achieved: 4-5 nC 1-1.5×108 e-/s for depletion Off the shelf laser: 3.5 W Immediately available: 1-2×108 @ 1, 1.7 GeV 108 @ 2.8 GeV Repetition rate: 30 photons in 0.1 ns at 6.528 MHz To get to higher fluxes * Booster upgrade for higher charge per shot * Implement new lattice for quiet injection for more frequent injection up to 2 Hz * More powerful laser/intracavity scattering: 10 times more Foreseeable:1-2×109 @ 1, 1.7 GeV 109 @ 2.8 GeV Repetition rate: 300 photons in 0.1 ns at 6.528 MHz Machine limit: 1011/s Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
Transverse injection: orbit disturbance Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
Longitudinal injection 5 ms 10 ms Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
Performance summary Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
Outline • Introduction: Existing g-ray facilities • APS overview • Why APS g-ray? • Compton scattering basics • Possible performance of APS g-ray facility • Booster • Storage ring • Laser systems • Summary Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
Commercial and custom lasers Example of custom laser with higher power: 4 W, 75 MHz at 527, 8 W @ 1053 nm, operating, J Lab 30 W, 75 MHz at 532, 60 W @ 1064 nm, under development, J Lab Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
Low rep output Eout=nEs=Es/loss Seed: high rep, low energy pulses f, Es Cavity with length matching the rep rate of the seed, L=1/f Laser: external buffer cavity Purpose: Laser repetition rate adjustment Intracavity scattering? Jones and Ye, Opt Lett 27, 1848 (2002) Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
Outline • Introduction: Existing g-ray facilities • APS overview • Why APS g-ray? • Compton scattering basics • Possible performance of APS g-ray facility • Booster • Storage ring • Laser systems • Summary Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
New g-ray flux distribution map 108/s @ 2.8 GeV GRAAL 3106/s @ 1.5 GeV LEGS 5106/s @ 0.5 GeV ROKK 3106/s @ 1.6 GeV 2106/s @ 1.5 GeV LEPS 5106/s @ 2.4 GeV HIGS 108/s @ 0.2 GeV More sunshine! Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
Challenges $ Funding Laser: 0.5 M Beam line: 0.5 M Misc: 1 M Detector ? Tagger ? Management commitment Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
Announcement Discussion What: Technical feasibility Physics possibilities When: 8:00 PM on Monday (today) Where: Ballroom in the Waikiki Terrace Hotel Who: Anyone interested Also: Dessert and coffee. Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu
Acknowledgement Advanced Photon Source S. V. Milton, L. Emery, N. Sereno, V. Sajaev, Y. Chae, J. Lewellen, Kathy Harkay, and Z Hunag George Washington University B. Berman and J. Feldman J Lab G. Neil Duke University V. Litvinenko Supported the U. S. Department of Energy, Office of Basic Energy Sciences, under Contract No. W-31-109-ENG-38. Workshop on New Aspects of Quark Nuclear Physics with Polarized Photons, Feb. 17-20, Honolulu