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SummaryIn order to better understand the regional tectonics of western part of Africa (WA) and adjacent islands, joint inversion (Jinv) of body wave and surface wave measurements is conducted to construct new sets of crustal models. Teleseismic P-wave receiver function, receiver function horizontal-to-vertical ratio and Rayleigh wave ellipticity are jointly inverted based on a fast simulated-annealing scheme. All three types of observables are derived from single-station recordings and are primarily sensitive to structures beneath the station. The integration of these datasets through Jinv allows for complementary constraints, thereby improving the resolution of crustal velocity structures and the characterization of velocity variations with depth. We present improved and some new crustal structure parameters including bulk crustal VP/VS ratio, crustal thickness (H) estimates, and shear-wave velocity (VS) models beneath 25 broad-band seismic stations across inland, coastal, and island terrains. Using an improved approach involving the correction of misorientation error effect from seismic waveform data, the data quality is well-enhanced leading to improved resolutions of structures across the different terrains. Results from H-k and crustal models showed a general northward thinning from Congo Craton (> ∼48 km) towards the Lower Benue Trough (∼15 km), and from coastal terrain along Gulf of Guinea (< ∼44 km) towards Mauritanian Belt (> ∼16 km). Compared to other terrains, the islands show very thin depth to the Moho, but higher than the global estimates. In the Mauritanian-Senegal Basin, sharp differential in crustal thickness and Jinv results at neigbouring G.SOK and G.MBO are observed, where slower Vs revealed a LVZ anomaly at G.SOK in contrast with faster Vs at G.MBO—which could be due to local subsidence from sediment loading, or uplift from tectonic activities. In the upper-middle crust, the Jinv imaged structures with faster VS characteristic of felsic to intermediate bulk crustal composition beneath inland terrain (West Africa Craton, Congo Craton, Hoggar), attributed to highly depleted and stable nature of the cratonic lithosphere, contributing to faster VS compared to other terrains. Low velocity structures underlying the island stations are attributed to partial melts and high temperature materials, indicative of volcanic and Basaltic composition. Similarly, the low velocity structures deciphered beneath coastal stations G.SOK and AF.EDA could be related to the structures in their adjacent areas of Tenerife and the Cameroon Volcanic Line, respectively. The nbroad range of VP/VS (∼1.58–1.85) ratio along the coastal terrains demonstrates its complexity; from the low VP/VS which may be attributed to indurated or low porosity sedimentary materials, and high VP/VS —typical of cracks, fluids inundated sedimentary or volcanic materials. Island terrain are associated with higher bulk VP/VS indicative of volcanics and Mafic-Basaltic materials, with the low velocity zones (LVZs) suggestive of the presence of magmatic materials. These broad crustal configuration highlights the complexity and provides new insight for developing more accurate regional model for western Africa and its adjacent islands, and global reference models in future studies.

Author(s): Ramesh Sasmal and Supratik Banerjee

Following a general heuristic approach, algebraic constraints are established between the parallel and perpendicular power-law exponents of nonaxisymmetric, highly aligned magnetohydrodynamic turbulence, both with and without a strong imbalance between the Elsässer variables. Such relations are univ…

[Phys. Rev. E 112, 035208] Published Tue Sep 16, 2025

Author(s): Meiqi Sun, Ze Chen, Lipan Qin, Zhongyi Chen, Yan Tian, Jin Yan, Yan Wang, Xunjie Ma, Xueqing Yan, and Yunliang Wang

An ultraintense, isolated circularly polarized (CP) attosecond x-ray pulse is often required for many application of pump-probe techniques. A quantum electrodynamics (QED) effect dominated coherent synchrotron emission (CSE) regime is proposed for the generation of an ultraintense isolated, nearly C…

[Phys. Rev. E 112, 035207] Published Mon Sep 15, 2025

Author(s): Arindam Mistri, Debkumar Chakraborty, and Samiran Ghosh

The steadily moving charged object (obstacle) induced modulated electrostatic ion cyclotron (EIC) wave dynamics is modeled through a forced nonlinear Schrödinger equation in collisionless and homogeneous plasmas. The disturbance created by the moving obstacle acts as the source of free energy and is…

[Phys. Rev. E 112, 035206] Published Thu Sep 11, 2025

Author(s): Johannes Gebhard, Peter Hilz, Felix Balling, Joey Kalis, Martin Speicher, Leonard Doyle, Alexander Sävert, Georg Schäfer, Pooyan Khademi, Bin Liu, Matt Zepf, and Jörg Schreiber

Isolated micro-targets are a promising avenue to high-performance laser-driven proton and ion accelerators due to their ability to confine the coupled laser energy to a small volume and small number of particles. Experimental results on proton emission from levitated plastic micro-spheres with an in…

[Phys. Rev. E 112, 035204] Published Tue Sep 09, 2025

Author(s): Wang-Wen Xu, Zhang-Hu Hu, Hao-Yuan Li, Jie-Jie Lan, and You-Nian Wang

We report in this work the current filamentation instability of laser-produced proton beams in a regime where the plasma collision frequency is much smaller than the plasma oscillation frequency but larger than the growth rate of the instability. In this regime, the plasma electron temperature incre…

[Phys. Rev. E 112, 035205] Published Tue Sep 09, 2025

Author(s): Tobias Dornheim, Thomas M. Chuna, Hannah M. Bellenbaum, Zhandos A. Moldabekov, Panagiotis Tolias, and Jan Vorberger

Spherically averaged periodic pair potentials offer the enticing promise to provide accurate results at a drastically reduced computational cost compared to the traditional Ewald sum. In this work, we employ the pair potential by Yakub and Ronchi [J. Chem. Phys. 119, 11556 (2003)] in ab initio path …

[Phys. Rev. E 112, 035203] Published Mon Sep 08, 2025

Author(s): Michael Updike, Nicholas Bohlsen, Hong Qin, and Nathaniel J. Fisch

A primary technical challenge for harnessing fusion energy is to control and extract energy from a nonthermal distribution of charged particles. The fact that phase space evolves by symplectomorphisms fundamentally limits how a distribution may be manipulated. While the constraint of phase-space vol…

[Phys. Rev. E 112, 035202] Published Fri Sep 05, 2025

Author(s): F.-X. Zhou, C.-W. Lian, R. Yan, Y. Ji, J. Li, Q. Jia, and J. Zheng

Absolute growth of stimulated Raman side scattering (SRSS) in inertial confinement fusion appears to be absent in experiments. Based on simulations the authors find that absolute growth of SRSS occurs only in the limit of an infinite laser beam width. This finding may have implications for the design of experiments.

#AdvancingField #OpenDebate

[Phys. Rev. E 112, L033201] Published Fri Sep 05, 2025

Author(s): Zhaoye Wang, Nichen Yu, Ao Xu, Chen Liang, C. Reichhardt, C. J. O. Reichhardt, and Yan Feng

Langevin dynamical simulations are performed to investigate the depinning dynamics of a two-dimensional (2D) solid dusty plasma, which is modulated by one-dimensional (1D) nonlinear deformed periodic substrates, and also driven by the combination of the DC and AC forces. As the DC driving force incr…

[Phys. Rev. E 112, 035201] Published Tue Sep 02, 2025

Author(s): A. A. Shelkovoy and S. A. Uryupin

Without imposing additional restrictions on the magnitude of induced scattering of waves by ions, the numerical solution of the nonlinear integral equation for the ion-acoustic waves distribution function over the angles of the wave vector is obtained. This solution complements the analytical and nu…

[Phys. Rev. E 112, 025210] Published Tue Aug 26, 2025

Author(s): J. A. S. Lima and M. H. Benetti

An extension of Maxwell's original prescription for an ideal gas is adopted to derive a broad class of kappa-type velocity distributions, encompassing both fat and short-tailed forms. Within this general framework, a physically consistent fat-tailed kappa distribution is identified that accurately f…

[Phys. Rev. E 112, 025211] Published Tue Aug 26, 2025

Author(s): R. Schlickeiser and M. Kröger

The observed Maxwellian velocity distribution functions in plasmas and the fact that the rate of elastic electron-electron collisions is many orders of magnitude smaller than the electron plasma frequency have been a long-standing puzzle. Here, we present a mechanism for efficient thermalization in …

[Phys. Rev. E 112, 025209] Published Thu Aug 21, 2025

Author(s): Oliver Mathiak, Lars Reichwein, and Alexander Pukhov

The separation of matter and antimatter in a plasma can be driven by the growth of the Weibel instability. The authors show this effect in a plasma of protons and antiprotons with a relativistic stream of electrons and positrons, by means of particle-in-cell simulations supported by analytical considerations.

#AdvancingField #OpenDebate

[Phys. Rev. E 112, 025208] Published Wed Aug 20, 2025

Author(s): Zachary A. Johnson, Nathaniel R. Shaffer, and Michael S. Murillo

Laboratory plasma production almost always preferentially heats either the ions or electrons, leading to a two-temperature state. In this state, density functional theory molecular dynamic simulation is the state of the art for modeling bulk material properties. We construct a statistical mechanics …

[Phys. Rev. E 112, 025207] Published Mon Aug 18, 2025

Author(s): A. V. Bernatskiy, I. I. Draganov, N. A. Dyatko, I. V. Kochetov, V. V. Lagunov, and V. N. Ochkin

Experimental and numerical studies of the features of the spatial distribution of plasma parameters in a discharge not limited by walls were performed. A discharge supported by a hollow cathode in helium at low pressure was ignited in a chamber with dimensions much larger than the dimensions of the …

[Phys. Rev. E 112, 025204] Published Thu Aug 14, 2025

Author(s): Michael F. Zhang, Seth Davidovits, and Nathaniel J. Fisch

We study the amplification of isotropic, incompressible turbulence through multiple planar, collisional shocks, using analytical linear theory. There are two limiting cases we explore. The first assumes shocks occur rapidly in time such that the turbulence does not evolve between shocks. Whereas the…

[Phys. Rev. E 112, 025205] Published Thu Aug 14, 2025

Author(s): Feiyu Li, Seth Dorfman, and Xiangrong Fu

The parametric decay instability (PDI) of Alfvén waves—where a pump Alfvén wave decays into a backward-propagating child Alfvén wave and a forward ion acoustic wave—is a fundamental nonlinear wave-wave interaction and holds significant implications for space and laboratory plasmas. However, to date …

[Phys. Rev. E 112, 025206] Published Thu Aug 14, 2025

Author(s): Shabbir A. Khan and Atsushi Fukuyama

Linear absorption of electromagnetic wave injected in a hot plasma is usually associated with non-normal incidence; here, it is shown that absorption can take place at normal incidence as well. By developing a kinetic model based on integral form of dielectric tensor in the presence of static electr…

[Phys. Rev. E 112, L023202] Published Thu Aug 07, 2025

Author(s): Iván Calvo, José Luis Velasco, Per Helander, and Félix I. Parra

Until now, quasi-isodynamic magnetic fields have been the only known stellarator configurations that, at low collisionality, give small radial neoclassical transport and zero bootstrap current for arbitrary plasma profiles, the latter facilitating control of the magnetic configuration. The recently …

[Phys. Rev. E 112, L023201] Published Wed Aug 06, 2025