Electron-positron pairs can be generated with lasers in various configurations, using either Breit-Wheeler or Bethe-Heitler pair production.
In some cases, the very same laser can provide direct laser acceleration (DLA) of leptons in the radiation reaction dominated regime. The DLA scheme has already provided electron beams of ~nC charge in experiments. Here we show what can be accomplished with near-future laser facilities with a special consideration of L4 beamline at ELI beamlines.
Increasing the laser power is bound to augment the DLA electron charge content even further. The field structure formed due to electron beam loading
allows for accelerating positrons without defocusing them. What is more, the interaction in the radiation dominated regime will provide a high flux of
emitted photons, in hard x-ray and gamma-ray range. These photons can then be used as a seed for electron-positron pair creation, as well as a radiation source for applications.
This work was supported by FCT grants CEECIND/01906/2018, PTDC/FISPLA/3800/2021. We acknowledge PRACE for granting access to MareNostrum in BSC, Spain.
Plasma acceleration has been lately considered to become an auspicious technology for building a future multi-TeV electron-positron collider, leading to higher compactness of the device. Self-generated fields from laser-plasma interaction are, however, in contrast to electrons, usually not well-suited for positron focusing and on-axis guiding. In addition, an external positron source is required. Here, we study the method of direct laser acceleration of positrons. The positron generation is assured by an orthogonal collision of a multi-PW laser pulse and a GeV electron beam by the nonlinear Breit-Wheeler process. The acceleration subsequently takes place in a preformed plasma channel with a finite (tens-of-microns-long) radius. In this work, we examine how the choice of channel radius influences the process of acceleration. We show that this scheme is robust regarding the radius size. A significant number of the positrons is kept near the propagation axis, even if the channel radius was increased by almost 100 µm. The mechanism was examined by quasi-3D particle-in-cell simulation carried out with the OSIRIS framework.
We study beam loading of electrons accelerated via the process of direct laser acceleration under the conditions of preformed plasma channels irradiated by ultra-intense laser pulses using analytical methods and particle-incell simulations in quasi-cylindrical geometry. We find the rates at which the electrons populate the beam for multi-petawatt peak power laser drivers. We show that the majority of accelerated electrons originate at the interface between the channel interior and channel wall and outline the underlying physical mechanism.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.