Sep 15 – 21, 2019
Hotel Hermitage, La Biodola Bay, Isola d'Elba, Italy
Europe/Rome timezone

External Injection experiment: first accelerated beam

Sep 18, 2019, 10:10 AM
SML (Hotel Hermitage)


Hotel Hermitage

talk Invited Plenary Talk Plenary Session 5


Jianfei Hua (Tsinghua University)


In recent studies on LWFA staging and external injection-acceleration in PWFA only a very small fraction (from below 0.1% to few percent) of the injected charge (the coupling efficiency) was accelerated. For future colliders where beam energy will need to be boosted using multiple stages, the coupling efficiency per stage must approach 100%. Here we report the first demonstration of external injection from a high-brightness RF photogun based conventional linear accelerator (LINAC) into a LWFA and subsequent acceleration without any significant loss of charge or degradation of quality. Stable 31-MeV, 20-fC electron beams from the LINAC were velocity bunched to the length of ~13fs (r.m.s.) in the high-gradient photocathode RF gun and then external injected into the linear wakefield excited by the 8TW, 40 fs laser. The experimental results show that nearly all the electrons can be mono-energetically accelerated with average gradient ~300 MV/m. This is achieved by properly shaping and matching the beam into the dedicatedly designed plasma structure. High capture efficiency of external injection has also been systematically validated by 3D PIC simulations. This is an important step towards realizing a high throughput, multi-stage high energy hybrid conventional-plasma accelerator.

Primary author

Jianfei Hua (Tsinghua University)


Mr Yipeng Wu (Tsinghua University) Mr Zheng Zhou (Tsinghua University) Mr Shuang Liu (Tsinghua University) Mr Bo Peng (Tsinghua University) Mr Yu Fang (Tsinghua University) Mr Jie Zhang (Tsinghua University) Dr Zan Nie (University of California Los Angeles) Prof. Chih-Hao Pai (Tsinghua University) Prof. Yingchao Du (Tsinghua University) Prof. Wei Lu (Tsinghua University of Beijing, China) Prof. Warren Bicknell Mori (University of California Los Angeles) Prof. Chan Joshi (University of California Los Angeles)

Presentation materials