ELFT HÍRADÓ

[<vera.horvath AT eli-alps.hu>]

Meghívó az ELI-ALPS szemináriumára

Előadó: Varró Sándor (ELI-ALPS, Wigner FK)
Cím:  Klein-Gordon radio and laser acceleration of particles (part 2)

Időpont: 2019. május 17. 9 óra
Helyszín: ELI-ALPS konferenciaterme (Szeged, Wolfgang Sandner utca 3.)

Absztrakt:
In the first part we have shown that the four potential of electromagnetic
fields in a plasma medium can be considered as a massive vector field, where
the mass is proportional with the plasma frequency. The plane waves of this
»Lánczos-Proca fields« have three orthogonal polarizatons, whose amplitudes
satisfy the Klein-Gordon equation. The expression „Klein-Gordon radio” in the
title of our talks has been borrowed from the paper by Crandall and Wheeler
[1], devoted to the study on a dynamical bound of photon mass. These authors
presented the peculiarities of wave propagation in free space, such as the
appearance of wake-fields and the special Doppler effect of radio signals from
a rapidly receding massy-photon transmitter. We have indicated that similar
phenomena are also relevant in the so-called laser wake-field accelerators and
in the generation of high harmonics (and attosecond pulses) in a plasma
environment. In this second part of the presentation, on the basis of recently
found new exact solutions of the relativistic wave equations of charged
particles [2], we also show that very high contrast density modulations are
generated, serving as »quantum bubbles« to accelerate electrons [3]. We also
consider exact analytic solutions of the relativistic equation of motion of a
point electron interacting with a high-intensity laser field in vacuum and in
a plasma medium [4], and compare the particle dynamics and the radiation
properties [5] in these two cases.

References.
[1] Crandall R E, Wheeler N A, Klein-Gordon radio and the problem of photon
mass. Nuovo Cim. 80B, 231 (1984).
[2] Varró S, New exact solutions of the Klein-Gordon and Dirac equations of a
charged particle propagating in a strong laser field in an underdense plasma.
Nucl. Instr. and Methods in Phys. Research A  740, 280-283 (2014).
[3] Varró S, Quantum description of relativistic charged particles interacting
with a strong laser field in a plasma, represented by Lanczos-Proca vector
bosons. Talk presented at EUCALL Joint Foresight Topical Workshop: Theory and
Simulation of Photon-Matter Interactions [ELI-ALPS, 1-6 July 2018, Szeged,
Hungary].
[4]Pocsai M A, Varró S and Barna I F, Electron acceleration in underdense
plasmas described with a classical effective theory. Laser and Particle Beams
33, 307-313 (2015). E-print: arXiv: 1406.6310 [nucl-th].
[5] Hack Sz, Varró S and Czirják A, Carrier-envelope phase controlled isolated
attosecond pulses in the nm wavelength range, based on coherent nonlinear
Thomson backscattering. New J. Phys. 20, 073043 (2018)

A szeminárium angol nyelvű. Minden érdeklődőt szívesen látunk.