Presentation on theme: "Strecher, compressor and time structure manipulation"— Presentation transcript:
1Strecher, compressor and time structure manipulation Xiangyu Zhou20. Feb. 2015
2Energy spread reduction using temporal manipulation Energy spread of 0.1% is required for SuperKEKB synchrotron injection.GaussianSquare5nC10nC15nC20nC5nC electronPrimary beam for positron productiontWhen the charge distribution is uniform in a cylinder, the energy spread of the bunch is lower than the result of Gaussian charge distribution.For the laser source, the pulse width should be reshaped to rectangle structure.
3Time structure of laser system Yb OscilattorStretcherYb PCFAmplifierYb:YAG thin-diskAmplifierSHG100 fs30 ps
4Grating Pair Stretcher and Compressor Short WavelengthLong WavelengthγθGratingPhase FrontRoof MirrorCompressorNegative GDDRoof MirrorLensZ-ffPhase FrontStretcherPositive GDD
15Slope injection at cathode Original pulse shaping8mm60°(Method-1)Grating6.92mm4mm6mm(20ps)9mm(30ps)(Method-2)Slit
16Problem Without CPA With CPA Fiber amplifier limitation (mJns) Spectral range adjustment is difficultWith CPAStructure of stretcher and compressor is hugeTransmission efficiencyDamage threshold of gratings