Progress on Laser-Driven MeV Electron-Positron Pair Experiments*

Relativistic electron-positron (pair) plasmas have unique properties due to their mass symmetry and may play an important role in energetic astrophysics. High-energy ps laser-target interactions have produced a large number (10¹⁰ – 10¹²) of positrons in a small volume (< 3 mm³) [1]. We have recently made significant progress in three areas of manipulating and optimizing these relativistic pairs: a) designed a magnetic mirror using pulsed-power-driven 13 T solenoids and validated the effectiveness of  the magnetic mirror by trapping MeV pairs for ns-timescales [2]; b) created a collimated charge-neutral pair beam [3] using a magnetic lens; c) realized pair yield enhancement by a factor of 2 using a micro-structured target [4]. These results and future plans will be presented. 

References

[1] H. Chen, et al., PRL (2015); H. Chen, et al., Phys. Plasmas (2015).

[2] J. von der Linden, et al, Phys. Plasmas, in review (2021)

[3] J. Peebles, et al., Phys. Plasmas, 28, 074501 (2021)

[4] S. Jiang, et al., Applied Phys. Lett. 118, 094101 (2021)