Joe Frisch: Synchrotron radiation sources and free ... - Conferences

More documents

Recommendations

Info

CSR Emittance Growth • FELs have higher gain and better efficiency with higher peak currents. • Coherent Synchrotron Radiation causes emittance degradation in bends for high peak currents Synchrotron radiation grows dramatically at wavelengths longer than the bunch length P. Emma Coherent Power Incoherent power e – Radiation from the trail of the bunch catches the head of the bunch producing an instability Bunch compressors limited to peak currents of a few KA for reasonable parameters. Improvements would be very valuable for future FEL projects. 22
FELs: Gain and Coherent Emission • Synchrotron light sources produce incoherent radiation – Electron positions are not correlated at X-ray wavelengths – X-ray phase produced by each electron is random – Fluctuations in the electric field go as N 1/2 so power goes as N – X-ray power linear in number of electrons • In an FEL the electrons are bunched at X-ray wavelengths • These bunches can then radiate in phase, field goes as N, power as N 2 until beam is fully bunched, then power saturates • Gain depends on peak current • If electron beam phase space (emittance and energy spread) is too large, the bunching required for gain will be washed out. – X-ray FELs place very stringent requirements on the electron beam. • A FEL CAN be described in a quantum-mechanical formulation to look like a laser, but this is not necessary or convenient for any proposed FELs. Much more intuitive to consider as a fully classical system. 23
Page 1 and 2: Synchrotron Radiation Sources and F
Page 3 and 4: X-ray Beam Parameters • Energy /
Page 5 and 6: Grazing incidence mirror Focusing X
Page 7 and 8: Undulator Radiation Most high brigh
Page 9 and 10: Accelerators Synchrotron LINAC Acce
Page 11 and 12: Light Source: Petra III at DESY •
Page 13 and 14: LINACS • Single pass devices •
Page 15 and 16: Electron Guns RF guns used at SLAC
Page 17 and 18: 100fs Room Temperature 200ns 10ms P
Page 19 and 20: Energy Time Initial beam Gun 6 MeV
Page 21: Bunch Compression - Wakefields •
Page 25 and 26: Undulator as emission mechanism 25
Page 27 and 28: Self Amplified Spontaneous Emission
Page 29 and 30: � � � u p 2� � � 2 �
Page 31 and 32: Gain, Saturation and Taper LCLS Gai
Page 33 and 34: Seeding • FEL light is amplified
Page 35 and 36: Laser Seeding (ECHO) Laser fundamen
Page 37 and 38: Synchrotron Multi-User Capability S
Page 39 and 40: Future Light X-ray Sources • Most
Page 41 and 42: Low energy injector gun Recirculati
Page 43 and 44: Attosecond FELs • Operation at lo
Page 45 and 46: Laser-Plasma Accelerators - LBNL Po
Page 47 and 48: What isn’t covered here: • Almo
Page 49: Discussion • Imagine you want to

Joe Frisch: Synchrotron radiation sources and free ... - Conferences

Create successful ePaper yourself

Delete template?

Save as template?