Enhanced electron–positron pair production by ultra intense laser irradiating a compound target

High-energy-density electron–positron pairs play an increasingly important role in many potential applications. Here, we propose a scheme for enhanced positron production by an ultra intense laser irradiating a gas-Al compound target via the multi-photon Breit–Wheeler (BW) process. The laser pulse first ionizes the gas and interacts with a near-critical-density plasma, forming an electron bubble behind the laser pulse. A great deal of electrons are trapped and accelerated in the bubble, while the laser front hole-bores the Al target and deforms its front surface. A part of the laser wave is thus reflected by the inner curved target surface and collides with the accelerated electron bunch. Finally, a large number of γ photons are emitted in the forward direction via the Compton back-scattering process and the BW process is initiated. Dense electron–positron pairs are produced with a maximum density of m−3. Simulation results show that the positron generation is greatly enhanced in the compound target, where the positron yield is two orders of magnitude greater than that in only the solid slab case. The influences of the laser intensity, gas density and length on the positron beam quality are also discussed, which demonstrates the feasibility of the scheme in practice.

[1]  T. Toyama,et al.  Microstructural evolution of RPV steels under proton and ion irradiation studied by positron annihilation spectroscopy , 2015 .

[2]  S. Wilks,et al.  EMITTANCE OF POSITRON BEAMS PRODUCED IN INTENSE LASER PLASMA INTERACTION , 2013 .

[3]  A. Pukhov,et al.  Betatron-like resonance in ultra-intense laser mass-limited foil interaction , 2013 .

[4]  A. Pukhov,et al.  Bright tunable femtosecond x-ray emission from laser irradiated micro-droplets , 2014 .

[5]  M. Borghesi,et al.  Simulation of relativistically colliding laser-generated electron flows , 2012, 1211.4195.

[6]  Julian Schwinger,et al.  On gauge invariance and vacuum polarization , 1951 .

[7]  A. Mills Efficient generation of low‐energy positrons , 1979 .

[8]  Lai Wei,et al.  Monte Carlo simulation study of positron generation in ultra-intense laser-solid interactions , 2012 .

[9]  K. Bennett,et al.  Modelling gamma-ray photon emission and pair production in high-intensity laser-matter interactions , 2013, J. Comput. Phys..

[10]  E. Liang Gamma-ray and pair creation using ultra-intense lasers and astrophysical applications , 2013 .

[11]  Z. Sheng,et al.  Bright betatronlike x rays from radiation pressure acceleration of a mass-limited foil target. , 2013, Physical review letters.

[12]  D. Habs,et al.  Relativistic laser-matter interaction and relativistic laboratory astrophysics , 2008, 0812.1421.

[13]  S. Baton,et al.  Density and temperature characterization of long-scale length, near-critical density controlled plasma produced from ultra-low density plastic foam , 2016, Scientific Reports.

[14]  Kirk T. McDonald,et al.  Positron Production in Multiphoton Light-by-Light Scattering , 1997 .

[15]  Zhi-Chao Zhu,et al.  Dense electron-positron plasmas and gamma-ray bursts generation by counter-propagating quantum electrodynamics-strong laser interaction with solid targets , 2015 .

[16]  C. Keitel,et al.  Ultrahigh Brilliance Multi-MeV γ-Ray Beams from Nonlinear Relativistic Thomson Scattering. , 2014, Physical review letters.

[17]  M. Tzoufras,et al.  Generating multi-GeV electron bunches using single stage laser wakefield acceleration in a 3D nonlinear regime , 2007 .

[18]  M. D. Tinkle,et al.  Creation and uses of positron plasmas , 1994 .

[19]  Hui Chen,et al.  Relativistic positron creation using ultraintense short pulse lasers. , 2008, Physical review letters.

[20]  R. G. Evans,et al.  Contemporary particle-in-cell approach to laser-plasma modelling , 2015 .

[21]  C. P. Ridgers,et al.  Dense electron-positron plasmas and bursts of gamma-rays from laser-generated quantum electrodynamic plasmas , 2013, 1304.2187.

[22]  Paul G. Coleman,et al.  Porosity and crystallization of water ice films studied by positron and positronium annihilation , 2011 .

[23]  K. Lynn,et al.  Enhanced slow positron reemission with new thin foil moderator geometry , 1990 .

[24]  W. Q. Wang,et al.  High-energy-density electron jet generation from an opening gold cone filled with near-critical-density plasma , 2015 .

[25]  Jun Zhao,et al.  High-flux low-divergence positron beam generation from ultra-intense laser irradiated a tapered hollow target , 2015 .

[26]  C. Keitel,et al.  Antimatter: Abundant positron production , 2009 .

[27]  B. Ye,et al.  A novel source of MeV positron bunches driven by energetic protons for PAS application , 2014 .

[28]  J. Meyer-ter-Vehn,et al.  POSITRON AND GAMMA-PHOTON PRODUCTION AND NUCLEAR REACTIONS IN CASCADE PROCESSES INITIATED BY A SUB-TERAWATT FEMTOSECOND LASER , 1997 .

[29]  T. Arber,et al.  Dense electron-positron plasmas and ultraintense γ rays from laser-irradiated solids. , 2012, Physical review letters.

[30]  B. Shen,et al.  Near QED regime of laser interaction with overdense plasmas , 2014 .

[31]  B. Xie,et al.  QED cascade induced by a high-energy γ photon in a strong laser field , 2013, 1312.2317.

[32]  Alexander Pukhov,et al.  Laser Hole Boring into Overdense Plasma and Relativistic Electron Currents for Fast Ignition of ICF Targets , 1997 .

[33]  K. Z. Hatsagortsyan,et al.  Extremely high-intensity laser interactions with fundamental quantum systems , 2011, 1111.3886.

[34]  Eric Esarey,et al.  Control of focusing fields for positron acceleration in nonlinear plasma wakes using multiple laser modes , 2014 .