FOR2783 2022

The role of laser focusing in nonlinear Breit-Wheeler pair production from collisions of bremsstrahlung γ quanta and a tightly focused laser pulse

12.09.2022, 16:45

45m

Lecture hall (LMU Munich - Garching)

Oral Electron-positron pair creation Electron-positron pair creation

Sprecher

Alina Golub (Heinrich-Heine-Universität Düsseldorf)

Beschreibung

Current experimental efforts toward the detection of the nonperturbative nonlinear strong-field regime of Breit-Wheeler pair creation plan to combine incoherent sources of GeV $\gamma$ quanta and tightly focussed optical laser pulses. This endeavour calls for a theoretical understanding of how the pair yields depend on the applied laser field profile [1]. In the present discussion, we provide estimates for the number of pairs produced in a setup where the high-energy radiation is generated via bremsstrahlung. Particular attention is paid to the role of the transversal and longitudinal focussing of the laser field, along with the incorporation of a (super-)Gaussian pulse envelope. The results are compared with predictions from plane-wave models and determine the parameters of focused laser pulses which maximize the pair yield at fixed pulse energy.

[1] A. Golub, S. Villalba-Chavez and C. Mueller,
Nonlinear Breit-Wheeler pair production in collisions of bremsstrahlung $\gamma$ quanta and a tightly focused laser pulse,
Phys. Rev. D 105, 116016 (2022)