FEL2022

Session

Seeded FELs

TUB

23 Aug 2022, 11:00

Auditorium Generali (Trieste Convention Centre)

Conveners

Seeded FELs

• Ryoichi Hajima (National Institutes for Quantum Science and Technology)

66. Coherent and Ultrashort Soft X-Ray Pulses from Echo-Enabled Harmonic Cascade FEL (TUBI1)

Chao Feng (Shanghai Advanced Research Institute)

23/08/2022, 11:00

Seeded FEL

Invited Orals

Shanghai Soft X-ray FEL facility (SXFEL) is the first X-ray FEL facility in China. Various external seeding techniques have been adopted for improving the performance of SXFEL. Here we report on the first demonstration of echo-enabled harmonic cascade (EEHC) for generating coherent and ultrashort soft X-ray pulses. Benefiting from the superiority of low sensitivity to the electron beam...

39. Enhanced Self-Seeding with Ultrashort Electron Beams (TUBI2)

Zhen Zhang (SLAC National Accelerator Laboratory), Erik Hemsing (SLAC National Accelerator Laboratory), Mr Aliaksei Halavanau (SLAC National Accelerator Laboratory)

23/08/2022, 11:30

Seeded FEL

Invited Orals

We describe a new method to produce intensity stable, highly coherent, narrow-band x-ray pulses in self-seeded free electron (FEL) lasers. The approach uses an ultrashort electron beam to generate a single spike FEL pulse with a wide coherent bandwidth. The self-seeding monochromator then notches out a narrow spectral region of this pulse to be amplified by a long portion of electron beam to...

179. Comparison of Transverse Coherence Properties in Seeded and Unseeded FEL (TUBO3)

Mihai Pop (Lund University), Nicola Mahne

23/08/2022, 11:55

Seeded FEL

Contributed Oral

The transverse coherence of the source is an important property for FEL experiments. Theory and simulations indicated different features for seeded and unseeded FELs but so far no direct comparison has been pursued experimentally on the same facility.
At FERMI one has the unique possibility to test both configurations (SASE and seeding) within the same operating conditions.
In this...

32. First Observation of Laser-Beam Interaction in a Dipole Magnet (TUBO4)

Jiawei Yan (European X-Ray Free-Electron Laser)

23/08/2022, 12:20

Seeded FEL

Contributed Oral

Recently, a self-modulation scheme was proposed and experimentally demonstrated for enhancing energy modulation in seeded FELs [1], thereby significantly reducing the requirement of an external laser system. Driven by this scheme, an electron beam with a laser-induced energy modulation as small as 1.8 times the slice energy spread is used for lasing at the 7th harmonic of a 266-nm seed laser...