Article
Astronomy & Astrophysics
Wenzhao Wang, Chong Lv, Xiaopeng Zhang, Changbo Fu, Bing Guo, Hongbo Cai, Liming Chen, Lei Cheng, Chuangye He, Jianjun He, Liang Li, Xiaofeng Xi, Dawei Yuan, Guoqiang Zhang, Wei Sun, Zhe Zhang, Jie Zhang, Yugang Ma
Summary: Nuclear fusion reactions are crucial for the production of energy and elements in the Universe. This study proposes an innovative self-calibration method to measure fusion reactions in plasma environments, addressing the uncertainties caused by plasma instabilities. It is applied for the first time to investigate the deuteron-lithium nuclear fusion reaction, providing insights into the Big Bang lithium abundance puzzle and demonstrating the insignificance of the coulomb screening effect. This method can also be applied to explore other fusion reactions and detect plasma dynamics.
Article
Astronomy & Astrophysics
P. Palmeri, J. Deprince, M. A. Bautista, S. Fritzsche, J. A. Garcia, T. R. Kallman, C. Mendoza, P. Quinet
Summary: This study calculates the modifications of ionization potentials and K-thresholds for abundant elements in plasma environments, and proposes improved universal fitting formulae for predicting these modifications. The results suggest that while the use of universal formulae is recommended for plasma modeling codes, their moderate to low accuracies may affect opacity predictions under extreme plasma conditions.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Physics, Fluids & Plasmas
G. M. Webb, S. C. Anco, S. Meleshko, G. P. Zank
Summary: The ideal Chew-Goldberger-Low (CGL) plasma equations are investigated using a Lagrangian variational principle, and conservation laws are derived via Noether's theorem. The Galilean group leads to the conservation of energy, momentum, centre of mass and angular momentum. The conservation of cross-helicity depends on the relationship between the entropy gradient and the magnetic induction. The point Lie symmetries of the CGL system consist of the Galilean transformations and scalings.
JOURNAL OF PLASMA PHYSICS
(2022)
Article
Physics, Multidisciplinary
Zhao Wang, Rui Cheng, Guodong Wang, Xuejian Jin, Yong Tang, Yanhong Chen, Zexian Zhou, Lulin Shi, Yuyu Wang, Yu Lei, Xiaoxia Wu, Jie Yang
Summary: A novel experimental method is proposed for observing plasma dynamics subjected to magnetic fields using a newly developed cylindrical theta-pinch device. The method involves simultaneously measuring the temporal profiles of multiple parameters to understand the plasma dynamics, such as shock transport and magnetohydrodynamic instability. The experimental data shows three phases of plasma evolution and offers insights into the radial implosion, axial flow, and anomalously heating phases, contributing to the understanding of plasma dynamics in the presence of magnetic fields.
MATTER AND RADIATION AT EXTREMES
(2023)
Review
Multidisciplinary Sciences
Ting Li, Eric Priest, Ruilong Guo
Summary: Magnetic reconnection is a fundamental process in various plasmas, with distinct characteristics in two dimensions compared to three dimensions. The focus here is on three-dimensional reconnection in the plasma environment of the Solar System, particularly solar flares. A new paradigm for solar flares, where three-dimensional reconnection plays a central role, is proposed.
PROCEEDINGS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES
(2021)
Review
Physics, Multidisciplinary
Jun-Jie Wei, Xue-Feng Wu
Summary: Explosive astrophysical transients at cosmological distances can provide precise tests of the basic assumptions of relativity theory, such as Lorentz invariance and the zero-mass hypothesis of photons. The study discusses signatures of Lorentz invariance violations and the consequences of a non-zero photon rest mass. By utilizing astrophysical sources and methods like dispersion, tests on the weak equivalence principle and photon mass limits can be conducted effectively.
FRONTIERS OF PHYSICS
(2021)
Article
Physics, Multidisciplinary
E. P. Hartouni, A. S. Moore, A. J. Crilly, B. D. Appelbe, P. A. Amendt, K. L. Baker, D. T. Casey, D. S. Clark, T. Doppner, M. J. Eckart, J. E. Field, M. Gatu-Johnson, G. P. Grim, R. Hatarik, J. Jeet, S. M. Kerr, J. Kilkenny, A. L. Kritcher, K. D. Meaney, J. L. Milovich, D. H. Munro, R. C. Nora, A. E. Pak, J. E. Ralph, H. F. Robey, J. S. Ross, D. J. Schlossberg, S. M. Sepke, B. K. Spears, C. Young, A. B. Zylstra
Summary: Inertial confinement fusion experiments at the National Ignition Facility aim to achieve sustained thermonuclear burn for energy generation. This study investigates the departure from hydrodynamic behavior when fusion reactions become the primary source of plasma heating. The relationship between ion temperature and mean ion kinetic energy is analyzed using neutron spectrum moments.
Editorial Material
Multidisciplinary Sciences
Alessio Belenchia, Matteo Carlesso, Sandro Donadi, Giulio Gasbarri, Hendrik Ulbricht, Angelo Bassi, Mauro Paternostro
Summary: By shooting glass beads across the inside of a satellite, it is possible to investigate the limits of quantum wave behavior.
Article
Physics, Fluids & Plasmas
R. A. Lopez, S. M. Shaaban, M. Lazar
Summary: Space plasmas exhibit non-thermal velocity distributions, anisotropies, and high-energy tails, which can be well represented by drifting bi-Kappa distribution functions for a kinetic description of the dynamics in collision-poor plasmas. The new solver DIS-K allows for numerically solving complex dispersion relations and has been validated by comparisons with other codes. These tools enable more realistic characterizations of wave fluctuations and instabilities in space plasmas.
JOURNAL OF PLASMA PHYSICS
(2021)
Article
Chemistry, Analytical
Liyi Gu, Chintan Shah, Ruitian Zhang
Summary: The uncertainties in theoretical atomic data are crucial for accurate plasma diagnostics, especially in astrophysical studies. This study presents a new calculation of the uncertainties in current theoretical ion-impact charge exchange atomic data and X-ray spectra, based on comparisons with existing laboratory data. The results show that the average systematic uncertainties are 35-88% for total cross sections and 57-75% for characteristic line ratios. Model deviation increases as collision energy decreases. The errors in total cross sections further contribute to significant uncertainty in the calculation of ionization balance in low-temperature collisional plasmas. Substantial improvements in the atomic database and dedicated laboratory measurements are needed to obtain current models for the next X-ray spectroscopic mission.
Article
Physics, Multidisciplinary
Matthew Goodbred, Yi-Hsin Liu
Summary: We have developed a first-principles model for the relativistic magnetic reconnection rate in strongly magnetized pair plasmas. Our analysis shows that in the magnetically dominated relativistic regime, the x-line thermal pressure is significantly lower than the upstream magnetic pressure, which leads to the collapse of the magnetic field lines and enables fast reconnection. This result is crucial for understanding various extreme astrophysical environments.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Multidisciplinary
Alexander Pukhov, Anton Golovanov, Igor Kostyukov
Summary: Electrostatic plasma wakefields radiate efficiently at harmonics of the plasma frequency when the plasma has a positive density gradient along the propagation direction of a driver. The wake can potentially serve as an efficient, narrow-band, and tunable source of terahertz radiation, emitting well-defined harmonics of the plasma frequency in the terahertz band.
PHYSICAL REVIEW LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Mate Szucs, Tamas Szepesi, Christoph Biedermann, Gabor Cseh, Marcin Jakubowski, Gabor Kocsis, Ralf Koenig, Marco Krause, Valeria Perseo, Aleix Puig Sitjes
Summary: The study investigates the use of machine learning models and algorithms to detect power detachment in fusion devices, specifically in the W7-X. By using pixel intensity profiles as input, the best performing model achieved high accuracy in both training and testing datasets, and demonstrated predictive capability in various scenarios.
APPLIED SCIENCES-BASEL
(2022)
Article
Physics, Fluids & Plasmas
Haidar Al-Naseri, Gert Brodin
Summary: In this study, the linear dispersion relation for Langmuir waves in plasmas of very high density was investigated using the Dirac-Heisenberg-Wigner formalism. It was found that the vacuum contribution leads to ultraviolet divergences, which were removed through charge renormalization. The remaining vacuum contribution was found to be small and consistent with previously derived expressions for time-dependent vacuum polarization. Additionally, a new damping mechanism, similar to Landau damping, was discovered, where the plasmon energy gives rise to the creation of electron-positron pairs. The dependence of the damping rate (pair-creation rate) on the wavenumber, temperature, and density was analyzed. Finally, the analytical results of the linearized theory were compared with numerical solutions.
PHYSICS OF PLASMAS
(2022)
Article
Engineering, Aerospace
Vladimir A. Sreckovic, Milan S. Dimitrijevic, Ljubinko M. Ignjatovic
Summary: This study investigates the photo-dissociation processes in symmetric and strongly non-symmetric systems involving hydrogen and potassium. The study aims to calculate data for small molecules and molecular state characterizations, as well as obtain corresponding partial and average cross-sections. The research provides spectral absorption rate coefficients for symmetric and strongly non-symmetric cases, which can be used for potential modeling in astrophysical plasma research and laboratory plasma investigation.
ADVANCES IN SPACE RESEARCH
(2023)
Article
Physics, Multidisciplinary
Yi-Hsin Liu, M. Hesse, F. Guo, W. Daughton, H. Li, P. A. Cassak, M. A. Shay
PHYSICAL REVIEW LETTERS
(2017)
Article
Astronomy & Astrophysics
Yi-Hsin Liu, M. Hesse, T. C. Li, M. Kuznetsova, A. Le
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2018)
Article
Physics, Multidisciplinary
Yi-Hsin Liu, W. Daughton, H. Karimabadi, H. Li, V. Roytershteyn
PHYSICAL REVIEW LETTERS
(2013)
Article
Physics, Fluids & Plasmas
Yi-Hsin Liu, J. F. Drake, M. Swisdak
PHYSICS OF PLASMAS
(2012)
Article
Astronomy & Astrophysics
Yi-Hsin Liu, Joachim Birn, William Daughton, Michael Hesse, Karl Schindler
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2014)
Article
Astronomy & Astrophysics
Yi-Hsin Liu, T. C. Li, M. Hesse, W. J. Sun, J. Liu, J. Burch, A. Slavin, K. Huang
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2019)
Article
Astronomy & Astrophysics
Xiaocan Li, Yi-Hsin Liu
Summary: Modeling the collisionless magnetic reconnection rate poses a significant challenge in basic plasma physics research. This study reveals a decreasing trend in reconnection rate and outflow speed as beta increases, and derives a simple analytical framework to consider the self-generated pressure anisotropy and pressure gradient in the force balance around the diffusion region. The predicted scaling of the normalized reconnection rate is found to be similar to O(0.1/root beta(i0)) in the high-beta limit.
ASTROPHYSICAL JOURNAL
(2021)
Article
Physics, Fluids & Plasmas
Shan-Chang Lin, Yi-Hsin Liu, Xiaocan Li
Summary: This study demonstrates that Petschek-type magnetic reconnection can be induced using a resistivity gradient in the reconnection outflow direction, with implications for reconnection-based thrusters and solar spicules. Numerical experiments show that the maximum plausible reconnection rate can be explored using localized resistivity at the x-line, leading to a significant decrease in current density without exceeding a normalized reconnection rate of about 0.2.
PHYSICS OF PLASMAS
(2021)
Article
Physics, Multidisciplinary
Yi-Hsin Liu, Paul Cassak, Xiaocan Li, Michael Hesse, Shan-Chang Lin, Kevin Genestreti
Summary: This article presents a self-consistent theory of the reconnection rate derived from first principles, and confirmed with numerical simulations. The theory explains why Sweet-Parker reconnection is slower, with the key consideration being the pressure at the reconnection site. These results have important implications for reconnection studies in solar flares, geomagnetic substorms, and other plasma-related fields.
COMMUNICATIONS PHYSICS
(2022)
Article
Physics, Multidisciplinary
Matthew Goodbred, Yi-Hsin Liu
Summary: We have developed a first-principles model for the relativistic magnetic reconnection rate in strongly magnetized pair plasmas. Our analysis shows that in the magnetically dominated relativistic regime, the x-line thermal pressure is significantly lower than the upstream magnetic pressure, which leads to the collapse of the magnetic field lines and enables fast reconnection. This result is crucial for understanding various extreme astrophysical environments.
PHYSICAL REVIEW LETTERS
(2022)
