Singel pass FELs for ERL

X-RAY FELS BASED ON ERL FACILITIES

A. Meseck,C. Mayes

F. LöhlG. Hoffstätter

Common knowledge: ERL can drive FEL-Oscillators

If we can compress the bunch about a factor of 10 and assume no-recovery:

Cornell ERL can drive:

- a SASE-FEL in hard x-ray regime by utilizing a modified current enhancement technique.

- a high power radiation of soft x-ray FEL: Using the fresh bunch technique, a radiator following a regular EEHG FEL can deliver soft X-rays.

- a high power radiation of hard x-ray FEL: Using an oscillator as the radiator in an Echo enabled FEL , a following radiator can deliver hard x-rays.

Cornell ERL can drive a SASE-FEL in hard x-ray regime by utilizing a modified current enhancement technique.

1 103 5 10

4 0 5 104 1 10

30

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200

1 103 5 10

4 0 5 104 1 10

30

100

200

300

400

current enhancement

Helical Undulator + Phase shifter

Nonlinear Harmonic Generation

fundamental

3rd harmonic

FELProperties ( saturation length: 48m)Photon Energy [keV]: 2.75667Pulse Energy [mJ]: 0.00563476# Photons: 1.27753e+10Effective Peak Power [GW]: 0.0301728RMS Pulse Length [fs]: 74.5023RMS Radius [micron]: 54.8423RMS Divergence Angle [micro-rad]: 6.99564RMS Bandwidth [%]: 0.11741Peak Spectral Flux [#ph/pulse/0.1% bw]: 1.08809e+10Peak Brightness [#ph/s/mm^2/mrad^2/0.1% bw]: 1.60004e+28Avg Brightness per pulse [#h/s/mm^2/mrad^2/0.1% bw]: 2.98806e+15

Using the fresh bunch technique, a radiator following a regular EEHG FEL can deliver high power radiation of soft x-rays.

FELProperties (Saturation length: 38m)Photon Energy [keV]: 0.372187Pulse Energy [mJ]: 0.0102175# Photons: 1.71579e+11Effective Peak Power [GW]: 0.220669RMS Pulse Length [fs]: 18.472RMS Radius [micron]: 74.8133RMS Divergence Angle [micro-rad]: 11.1797RMS Bandwidth [%]: 0.0201966Peak Spectral Flux [#ph/pulse/0.1% bw]: 8.49541e+11Peak Brightness [#ph/s/mm^2/mrad^2/0.1% bw]: 1.06017e+30Avg Brightness per pulse [#ph/s/mm^2/mrad^2/0.1% bw]: 4.90884e+16

Using an oscillator as the radiator in an Echo enabled FEL , a following radiator can deliver radiation pulses of hard x-rays.

The stored power in the resonator. It has to be filled with as much radiation as necessary to ensure that the undisturbed electrons modulated in the oscillator will emit enough power to replace the losses in the actual pass.

P [

W]

FELProperties (Saturation length: 10m)Photon Energy [keV]: 3.19387Pulse Energy [mJ]: 0.000352517# Photons: 6.89831e+08Effective Peak Power [GW]: 0.00127671RMS Pulse Length [fs]: 110.153RMS Radius [micron]: 50.5324RMS Divergence Angle [micro-rad]: 4.17639RMS Bandwidth [%]: 0.0195302Peak Spectral Flux [#ph/pulse/0.1% bw]: 3.53212e+09Peak Brightness [#ph/s/mm^2/mrad^2/0.1% bw]: 1.16096e+28Avg Brightness per pulse [#ph/s/mm^2/mrad^2/0.1% bw]: 3.20557e+15