Quasimonoenergetic laser plasma positron accelerator using particle-shower plasma-wave interactions

Abstract

An all-optical centimeter-scale laser-plasma positron accelerator is modeled to produce quasimonoenergetic beams with tunable ultrarelativistic energies. A new principle elucidated here describes the trapping of divergent positrons that are part of a laser-driven electromagnetic particle-shower with a large energy spread and their acceleration into a quasimonoenergetic positron beam in a laser-driven plasma wave. Proof of this principle using analysis and particle-in-cell simulations demonstrates that, under limits defined here, existing lasers can accelerate hundreds of MeV pC quasi-monoenergetic positron bunches. By providing an affordable alternative to kilometer-scale radio-frequency accelerators, this compact positron accelerator opens up new avenues of research. DOI: 10.1103/PhysRevAccelBeams.21.081301 Monoenergetic positron accelerators intrinsic to positronelectron (e þ − e − ) colliders at energy frontiers [1,2] have been fundamental to many important discoveries [3][4][5][6] that underpin the standard model. Apart from highenergy physics (HEP), monoenergetic e þ -beams of mostly sub-MeV energies are also used in many areas of material science [7,8] Positron accelerators have evidently been scarce due to complexities involved in the production and isolation of elusive particles like positrons [2,16] in addition to the costs associated with the large size of radio-frequency (rf) accelerators [17]. The size of conventional rf accelerators is dictated by the distance over which charged particles gain energy under the action of breakdown limited [18] tens of MVm −1 rf fields sustained using metallic structures that reconfigure transverse electromagnetic waves into modes with axial fields. This limit also complicates efficient positron production [2,13], which has required a multi-GeV e − -beam from a kilometer-scale rf accelerator [17] to interact with a target. Furthermore, the positrons thus produced have to be captured in a flux concentrator, turned around and transported back [19] for reinjection into the same rf accelerator.Advancements in rf technologies have demonstrated 100 MVm −1 -scale fields [20] but explorations beyond the standard model at TeV-scale e þ − e − center-of-mass energies still remain unviable. Moreover, the progress of non-HEP applications of e þ -beams has been largely stagnant.Recent efforts on compact and affordable positron accelerator design based on advanced acceleration techniques [21,22] have unfortunately been unsatisfactory. Production of e þ − e − showers using high-energy electrons from FIG. 1. Schematic of all-optical centimeter-scale schemes of quasimonoenergetic laser-plasma positron accelerator using the interaction of e þ − e − showers with plasma-waves.

Schemes of Laser Muon Acceleration: Ultra-short, Micron-scale Beams

“…Apart from this, a two-stage laser e accelerator 4 and a laser positron (e + ) accelerator 5 are also under active investigation 6 . These advances in acceleration techniques coupled with the rapid ongoing development of CPA lasers open up the possibility of an a↵ordable high-energy physics (HEP) e + -e collider 7 at the energy-frontier.…”

Laser-Wakefield Electron Beams as Drivers of High-Quality Positron Beams and Inverse-Compton-Scattered Photon Beams

“…These values are already compatible with a further injection in secondary acceleration stages and to perform proof-of-principle studies of novel acceleration schemes. By injecting the positron beam into secondary plasma stages, quasimonoenergetic positron beams can be produced and accelerated using all-optical configurations [107].…”

Schemes of laser muon acceleration: Ultra-short, micron-scale beams

“…Apart from this, a two-stage laser e accelerator 4 and a laser positron (e + ) accelerator 5 are also under active investigation 6 . These advances in acceleration techniques coupled with the rapid ongoing development of CPA lasers open up the possibility of an a↵ordable high-energy physics (HEP) e + -e collider 7 at the energy-frontier.…”

“…However, laser acceleration of exotic particles remains largely unexplored. Laser acceleration of positrons in gaseous plasmas has been introduced using an innovative model of controlled interaction of positron-electron pair plasmas or particle showers with laser driven plasmas 5 . There have been recent e↵orts towards experimental prototyping of laser positron accelerator 6 .…”

“…In this work we introduce mechanisms of laser acceleration of muon (µ ± ) 10 , an exotic fundamental particle which as a second generation lepton. The mechanism introduced here follows the same methodology as the laser positron accelerator 5 and is well within the reach of the experimental capabilities of existing laser-plasma and RF acceleration test facilities. We propose and analyze the short-term experimental viability of various muon production schemes and demonstrate the processing and acceleration of the generated muons using laser-driven plasmas.…”