Neutrino-electron magnetohydrodynamics in an expanding Universe

Physical Review D: Particles, Fields, Gravitation and Cosmology American Physical Society 104:12 (2021) 123013


LM Perrone, Gianluca Gregori, B Reville, LO Silva, R Bingham


We derive a new model for neutrino-plasma interactions in an expanding universe that incorporates the collective effects of the neutrinos on the plasma constituents. We start from the kinetic description of a multi-species plasma in the flat Friedmann-Robertson-Walker metric, where the particles are coupled to neutrinos through the charged- and neutral-current forms of the weak interaction. We then derive the fluid equations and specialize our model to (a) the lepton epoch, where we consider a pair electron-positron plasma interacting with electron (anti-)neutrinos, and (b) after the electron-positron annihilation, where we model an electron-proton plasma and take the limit of slow ions and inertia-less electrons to obtain a set of neutrino-electron magnetohydrodynamics (NEMHD) equations. In both models, the dynamics of the plasma is affected by the neutrino motion through a ponderomotive force and, as a result, new terms appear in the induction equation that can act as a source for magnetic field generation in the early universe. A brief discussion on the possible applications of our model is proposed.

Relativistic Landau quantization in non-uniform magnetic field and its applications to white dwarfs and quantum information

SciPost Physics SciPost 11:2021 (2021) 093


We investigate the two-dimensional motion of relativistic cold electrons in the presence of ‘strictly’ spatially varying magnetic fields satisfying, however, no magnetic monopole condition. We find that the degeneracy of Landau levels, which arises in the case of the constant magnetic field, lifts out when the field is variable and the energy levels of spin-up and spin-down electrons align in an interesting way depending on the nature of change of field. Also the varying magnetic field splits Landau levels of electrons with zero angular momentum from positive angular momentum, unlike the constant field which only can split the levels between positive and negative angular momenta. Exploring Landau quantization in non-uniform magnetic fields is a unique venture on its own and has interdisciplinary implications in the fields ranging from condensed matter to astrophysics to quantum information. As examples, we show magnetized white dwarfs, with varying magnetic fields, involved simultaneously with Lorentz force and Landau quantization affecting the underlying degenerate electron gas, exhibiting a significant violation of the Chandrasekhar mass-limit; and an increase in quantum speed of electrons in the presence of a spatially growing magnetic field.

A laser-plasma platform for photon-photon physics: the two photon Breit-Wheeler process

NEW JOURNAL OF PHYSICS IOP Publishing 23:11 (2021) ARTN 115006


B Kettle, D Hollatz, A Alejo, C Baird, S Bohlen, M Campbell, C Colgan, D Dannheim, C Gregory, H Harsh, P Hatfield, J Hinojosa, Y Katzir, J Morton, Cd Murphy, A Nurnberg, J Osterhoff, G Perez-Callejo, Pp Rajeev, C Roedel, Mjv Streeter, Agr Thomas, C Underwood, R Watt, Spd Mangles

A feasibility study of using X-ray Thomson Scattering to diagnose the in-flight plasma conditions of DT cryogenic implosions

ArXiv 2110.14361 (2021)


H Poole, D Cao, R Epstein, I Golovkin, T Walton, SX Hu, M Kasim, SM Vinko, JR Rygg, VN Goncharov, G Gregori, SP Regan

GeV-scale accelerators driven by plasma-modulated pulses from kilohertz lasers

Physical Review Letters American Physical Society 127 (2021) 184801


O Jakobsson, SM Hooker, R Walczak


We describe a new approach for driving GeV-scale plasma accelerators with long laser pulses. We show that the temporal phase of a long, high-energy driving laser pulse can be modulated periodically by copropagating it with a low-amplitude plasma wave driven by a short, low-energy seed pulse. Compression of the modulated driver by a dispersive optic generates a train of short pulses suitable for resonantly driving a plasma accelerator. Modulation of the driver occurs via well-controlled linear processes, as confirmed by good agreement between particle-in-cell (PIC) simulations and an analytic model. PIC simulations demonstrate that a 1.7 J, 1 ps driver, and a 140 mJ, 40 fs seed pulse can accelerate electrons to energies of 0.65 GeV in a plasma channel with an axial density of 2.5 × 1017cm−3. This work opens a route to high repetition-rate, GeV-scale plasma accelerators driven by thin-disk lasers, which can provide joule-scale, picosecond-duration laser pulses at multikilohertz repetition rates and high wall-plug efficiencies.