You are cordially invited to the SCL seminar of the Center for the Study of Complex Systems, which will be held on Monday, 15 September 2025 at 14:00 in the "Zvonko Marić" lecture hall of the Institute of Physics Belgrade. The talk entitled

Towards Laboratory Electron-Positron Plasma via Electromagnetic Showers

will be given by Thomas Grismayer (GoLP/IPFN Instituto Superior Tecnico, Universidade de Lisboa). The abstract of the talk:

When a relativistic electron interacts with a strong field, the combination of photon emission and pair creation leads to an Electromagnetic Shower (EMS). New Petawatt laser facilities offer an opportunity to accelerate multi-GeV electrons using plasma technology, to generate strong laser electromagnetic fields, and are therefore ideal for probing EMS and pursuing the long-standing objective of generating a pair plasma in the laboratory [1]. Despite efforts in understanding the shower properties, a complete theory of showers in all regimes is yet to be found.

We use a generation-splitting method and derive expressions for the shower multiplicity and particle spectra at short and long times. We apply our approach to showers in the Coulomb field of neutral targets and strong external fields. The analytical results are compared with PIC codes, Geant4, and a Monte Carlo code. Our results are predictive for realistic future experiments: the collisions of electrons with a high-intensity laser [2]. Additionally, we consider the interaction of an electron beam with matter to provide a simple criterion for pair plasma production as a function of the incident beam properties [3].

Acknowledgments: FCT (Portugal) Grant No. CEECIND/04050/2021 and ANR (g4QED project, Grant No.. ANR-23-CE30-0011)


[1] G. Sarri et al., Nature Communications 10.1038/NCOMMS7747 (2015); C. D. Arrowsmith et al., Nature Communications 15, 10.1038/s41467-024-49346-2 (2024), H. Chen and F. Fiuza, Physics of Plasmas 30, 020601 (2023).
[2] M. Pouyez et al., Physical Review Letters 134.13, 135001 (2025)
[3] M. Pouyez et al., arXiv:2505.18843 (2025)