Optimal positron-beam excited plasma wakefields in Hollow and Ion-Wake channels
| Autor: | Sahai, Aakash A., Katsouleas, T. C. |
|---|---|
| Rok vydání: | 2015 |
| Předmět: | |
| Druh dokumentu: | Working Paper |
| Popis: | A positron-beam interacting with the plasma electrons drives radial suck-in, in contrast to an electron-beam driven blow-out in the over-dense regime, $n_b>n_0$. In a homogeneous plasma, the electrons are radially sucked-in from all the different radii. The electrons collapsing from different radii do not simultaneously compress on-axis driving weak fields. A hollow-channel allows electrons from its channel-radius to collapse simultaneously exciting coherent fields. We analyze the optimal channel radius. Additionally, the low ion density in the hollow allows a larger region with focusing phase which we show is linearly focusing. We have shown the formation of an ion-wake channel behind a blow-out electron bubble-wake. Here we explore positron acceleration in the over-dense regime comparing an optimal hollow-plasma channel to the ion-wake channel. The condition for optimal hollow-channel radius is also compared. We also address the effects of a non-ideal ion-wake channel on positron-beam excited fields. Comment: Proceedings of IPAC2015, Richmond, VA, USA 3: Alternative Particle Sources and Acceleration Techniques A22 - Plasma Wake eld Acceleration http://accelconf.web.cern.ch/AccelConf/IPAC2015/papers/wepje001.pdf, 2015 (ISBN 978-3-95450-168-7) pp 2674-2677 |
| Databáze: | arXiv |
| Externí odkaz: |
|