Superstrong Magnetic Field Research Articles

Model of astrophysical jets in magnetic fields of laser relativistic plasmas

A brief review of the results of experimental modeling of cosmic jets in superstrong magnetic fields of laser relativistic plasma is given. It is noted that the development of cyclotron instability with the generation of cyclotron radiation plays a key role in a number of processes in a plasma with a magnetic field — self-localization of plasma in the form of solitons, conversion of rotational motion of plasma into translational motion, cyclotron acceleration of charged particles, separation (stratification) of a plasma jet into separate plasma formations.

Anomalous conductivity due to relativistic Landau quantization.

We use a recently developed a kinetic model derived from the Dirac equationto study electromagnetic wave propagation in superstrong magnetic fields, such as in magnetars, where relativistic Landau quantization is prominent. The leading contribution to the conductivity tensor in such a plasma is calculated. It is found that the electron Hall current has an anomalous contribution, in the quantum relativistic regime, where the effective particle energy has a significant contribution from the diamagnetic and Zeeman energy. As a result, a new quantum resonance frequency appears, and the dispersion relation for the left- and right-hand polarized modes are strongly modified for long and moderate wavelengths. The implications for magnetar physics are discussed.

About splitting of energy gap in superfluid neutron matter with spin-triplet anisotropic p-wave pairing at nuclear and supranuclear densities in superstrong magnetic fields

About splitting of energy gap in superfluid neutron matter with spin-triplet anisotropic <i>p-</i>wave pairing at nuclear and supranuclear densities in superstrong magnetic fields

Review of recent analytical advances in the spectroscopy of hydrogenic lines in plasmas

Abstract Broadening of hydrogenic spectral lines is an important tool in spectroscopic diagnostics of various laboratory and astrophysical plasmas. We review recent analytical advances in three areas. First, we review the analytical solution for the splitting of hydrogenic lines under the combination of a circularly polarized electromagnetic wave with a strong magnetic field. Practical applications of this solution relate to the spectroscopic diagnostic of the electron cyclotron waves and to the relativistic laser–plasma interactions. Second, we review analytical results concerning the Stark–Zeeman broadening of the Lyman-alpha (Ly-alpha) line in plasmas. These results allow for the Stark width of the Ly-alpha π-component to be used for the experimental determination of the ion density or of the root-mean-square field of a low-frequency electrostatic plasma turbulence in the situation where the Zeeman effect dominates over the Stark effects. Third, we review recent analytical advances in the area of the intra-Stark spectroscopy: three different new methods, based on the emergent phenomenon of the Langmuir-wave-caused structures (“L-dips”) in the line profiles, for measuring super-strong magnetic fields of the GigaGauss range developing during relativistic laser–plasma interactions. We also review the rich physics behind the L-dips phenomenon – because there was a confusion in the literature in this regard.

Surface Polishing of an Inconel 625 Bar by a Super-Fast MAF Process for a Solenoid Valve Stem Used in a Hydrogen Tank

This study explores a super-fast magnetic abrasive finishing (MAF) process for polishing the surface of an Inconel 625 bar workpiece for a hydrogen solenoid valve stem. The Inconel 625 bar was chosen to replace the existing STS 316 bar material, previously used for a hydrogen solenoid valve stem. The cylindrical surface of Inconel 625 bars was polished by a super-fast MAF process with high rotational speeds of 1000, 5000, 15,000, and 25,000 RPM and a super-strong magnetic field of 550 mT. The polishing characteristics of this process were evaluated according to the type of abrasives, rotational speeds of the workpiece and processing time. As a result, a super-smooth Inconel 625 bar was successfully achieved, with a surface roughness (Ra) reduced from 0.31 μm to 0.02 μm under the optimal conditions (15,000 RPM, CNT particles (0.04 μm), PCD diamond abrasive (1 μm), Fe (#200), 0.5 g of light oil, and 16 min of processing time). Also, the Ansys analysis results showed suitable strain, equivalent stress, and safety factor of the Inconel 625 bar. This confirmed that, after a super-fast MAF process, an Inconel 625 bar is feasible for application in Hydrogen (H2) tanks instead of a conventional STS 316 bar.

X-ray Polarization from Magnetar Sources

The launch of the IXPE telescope in late 2021 finally made polarization measurements in the 2–8keV band a reality, more than 40 years after the pioneering observations of the OSO-8 satellite. In the first two years of operations, IXPE targeted more than 60 sources, including four magnetars, neutron stars with magnetic fields in the petaGauss range. In this paper we summarize the IXPE main findings and discuss their implications for the physics of ultra-magnetized neutron stars. Polarimetric observations confirmed theoretical predictions, according to which X-ray radiation from magnetar sources is highly polarized, up to ≈80%, the highest value detected so far. This provides an independent confirmation that magnetars are indeed endowed with a super-strong magnetic field and that the twisted magnetosphere scenario is the most likely explanation for their soft X-ray emission. Polarization measurements allowed us to probe the physical conditions of the star’s outermost layers, showing that the cooler surface regions are in a condensed state, with no atmosphere on top. Although no smoking-gun of vacuum QED effects was found, the phase-dependent behavior of the polarization angle strongly hints that vacuum birefringence is indeed at work in magnetar magnetospheres.

Cosmic Baby and the r-process Nucleosynthesis

Astrophysical origin of the rapid neutron capture process (i.e., r-process) remains a mystery. Among the known r-process sites radio-actively powered kilonova, produced by binary neutron star mergers, attracted the astronomers a promising source in the light of gravitational wave radiation. The first detected binary neutron star merger event GW170817 confirmed the existence of binary neutron star (BNS) in nature while its associated properties such as transient electro-magnetic emission in the form of x-rays, long and short gamma ray bursts (l, s GRBs), First Radio Bursts (FRBs) offer the astronomer to rethink about the origin of the r-process abundances in the light of Magnetars, created in both supernova explosion and also in neutron star merger, as a r-process contributor. Recently detected Cosmic Baby i.e. Swift J1818.0 – 1607 is a young magnetar of 240 years aged with super-strong magnetic fields ~ 8.9424 x 1017 G and ellipticity ~ 9 x 10-3. Due to its youngness among the 31 detected magnetars till today, it may provide x-ray lines emitted by the r-process abundances which makes it as an important promising source in the eyes of LOFT, NuSTAR detectors. This author proposes that this cosmic baby can be considered as a suitable astrophysical source decoding of its observed results may unravel the realistic situations of the magnetar at the time of merger, supernova explosion, etc. for generation of super heavy elements like Eu, Ti.

Zeeman Splitting of Torsional Oscillation Frequencies of Magnetars

Magnetars form a special class of neutron stars possessing superstrong magnetic fields and demonstrating power flares triggered by these fields. Observations of such flares reveal the presence of quasi-periodic oscillations (QPOs) at certain frequencies; they are thought to be excited in the flares. QPOs carry potentially important information on magnetar structure, magnetic field, and mechanisms of magnetar activity. We calculate frequencies of torsional (magneto-elastic) oscillations of the magnetar crust treating the magnetic field effects in the first order of perturbation theory. The theory predicts the splitting of non-magnetic oscillation frequencies into Zeeman components. Zeeman splitting of the torsional oscillation spectrum of magnetars was suggested, clearly described and estimated by Shaisultanov and Eichler (2009), but their work has not been given considerable attention. To extend it, we suggest the technique of calculating oscillation frequencies, including Zeeman splitting at not too strong magnetic fields for arbitrary magnetic field configuration. Zeeman splitting enriches the oscillation spectrum and simplifies the theoretical interpretation of observations. We calculate several low-frequency oscillations of magnetars with a pure dipole magnetic field in the crust. The results qualitatively agree with the low-frequency QPOs detected in the hyperflare of SGR 1806–20 and in the giant flare of SGR 1900+14.

Unique spectral manifestations around the D3 line observed in the region close to the seismic source of a large solar flare

ABSTRACT The main goal of our research is to search for super-strong magnetic fields in active processes on the Sun. Our method is based on Stokes V spectro-polarimetry in a wide spectral range from −14 Å to +29 Å relative to the D3 He i line. The object of the study is the area of a seismic source in the large solar flare on 2003 October 28 of the X17.2/4B class. The novelty of our study: we found characteristic spectral manifestations – secondary Stokes V peaks – far from D3 line, at distances of several angstroms. These secondary peaks have the following features: (a) their amplitudes reach 4 per cent – almost an order of magnitude more than previously detected in other flares, (b) in the general picture, the sign of the circular polarization changes when passing through the D3 centre, and (c) narrower spectral peculiarities were found at distances of +4.0, +6.3, and +8.5 Å, where the polarization sign also changes sharply. This unusual feature likely results from significant factors in the area of the seismic source, including substantial descending plasma velocities which exceed 400 km s−1 and, perhaps, super-strong magnetic fields.

About magnetic properties of superfluid neutron matter with spin-triplet anisotropic p-wave pairing in superstrong magnetic fields and at supranuclear densities

Magnetic properties of a dense superfluid neutron matter (relevant to the physics in cores of magnetars, namely the strongly magnetized neutron stars) at supranuclear densities n &amp;gt; n0 (where n0 = 0.17 fm–3 is the saturation nuclear density) with generalized Skyrme effective forces (with three density-dependent terms) and with spin-triplet anisotropic p-wave pairing (similar to 3He-A in magnetic fields, i.e. with spin S = 1 and orbital moment L = 1 of anisotropic Cooper pairs of neutrons) in the presence of a superstrong magnetic field (exceeding the 1017 G) are studied within the framework of the non-relativistic generalized Fermi-liquid theory at zero temperature. The upper limit for the density range of a neutron matter is restricted by the magnitude 3n0 in order to avoid the account of relativistic corrections growing with density. The approximate general formula (valid for any parameterization of the Skyrme forces) is derived here analytically for the magnetic susceptibility (which contains additional correction depending nonlinearly on superstrong magnetic field H and on the density n) of a superfluid neutron matter in the limit of zero temperature. The obtained general formula for magnetic susceptibility is specified for the generalized BSk21 parameterization of the Skyrme forces and figures for corresponding values are plotted on the interval 1.5n0 ≤ n ≤ 3n0 and for superstrong magnetic fields 2⋅1017 G ≤ H ≤ 2⋅1018 G. It is established that the high-density ferromagnetic instability is removed in neutron matter with the generalized Skyrme forces (in particular, with the generalized BSk21 parameterization) not only in normal, but also in superfluid neutron matter with spin-triplet anisotropic p-wave pairing at supranuclear densities and in superstrong magnetic fields.

The impact of quantized magnetic pressure on the stimulated Brillouin scattering of electromagnetic waves

Within the frame work of Landau quantization theory of Fermi gas, we formulate here the exotic physics of magnetic stimulated Brillouin scattering instability (MSBS) arising due to the nonlinear interaction of high frequency electromagnetic waves (EMWs) with degenerate, strongly magnetized electron-ion plasma. Quantum magneto hydrodynamic model (QMHD) is followed to develop the basic differential equations of quantized magnetosonic waves (QMWs) in the presence of super strong magnetic (SSH) field, whereas Maxwell equations are used to derive the governing differential equation of pump EMWs. The nonlinear interaction of EMWs and QMWs is addressed by employing the phasor matching technique. The obtained dispersion relation of MSBS shows that for a fixed density of fermions, the SSH field alone suppresses the MSBS instability as a function of quantized magneto ion velocity (C He ) and the Alfven speed (V A ) via three-wave decay and modulational instabilities. However, for particular condition the MSBS instability is found to increase as a function of SSH field. Next, the analytical results are verified numerically and graphically for soft x-rays in the environment of neutron star. The present MSBS analysis may be critical in neutron stars, radio pulsars and magnetars having super strong magnetic field i.e. even larger than the quantum threshold value i.e, H ∼ 4.4 × 1013 G, or in any application where the enhancement or suppression of SBS may be important.

Spectral manifestations of strong and super-strong magnetic fields in an active prominence on July 24, 1999

Spectral manifestations of strong and super-strong magnetic fields in an active prominence on July 24, 1999

Plasma modes in QED super-strong magnetic fields of magnetars and laser plasmas

Ultra-magnetized plasmas, where the magnetic field strength exceeds the Schwinger field of about BQ≈4×1013 G, become of great scientific interest, thanks to the current advances in laser-plasma experiments and astrophysical observations of magnetar emission. These advances demand better understanding of how quantum electrodynamics (QED) effects influence collective plasma phenomena. In particular, Maxwell's equations become nonlinear in the strong-QED regime. Here we present the “QED plasma framework,” which will allow one to systematically explore collective phenomena in a QED-plasma with arbitrary strong magnetic field. Further, we illustrate the framework by exploring low-frequency modes in the ultra-magnetized, cold, electron-positron plasmas. We demonstrate that the classical picture of five branches holds in the QED regime; no new eigenmodes appear. The dispersion curves of all the modes are modified. The QED effects include the overall modification to the plasma frequency, which becomes field-dependent. They also modify resonances and cutoffs of the modes, which become both field- and angle-dependent. The strongest effects are (i) the field-induced transparency of plasma for the O-mode via the dramatic reduction of the low-frequency cutoff well below the plasma frequency, (ii) the Alfvén mode suppression in the large-k regime via the reduction of the Alfvén mode resonance, and (iii) the O-mode slowdown via strong angle-dependent increase in the index of refraction. These results should be important for understanding of a magnetospheric pair plasma of a magnetar and for laboratory laser-plasma experiments in the QED regime.

Search for superstrong magnetic fields in active processes on the Sun using spectro-polarimetry within 15 Å around the D3 line

ABSTRACT We critically review our previous results on this topic based on the following main points: (i) substantially larger wavelength range around the D3 line was investigated – up to ±15 Å instead of ±2.5 Å in comparison with the previous version of our study, and (ii) greater volume of observational data was analysed, including one X limb flare, additionally. Overall, our study concerns the 2004 July 12 active prominence and the 2014 June 10 limb flare of X1.5 class. For named limb flare, we found reliable and oppositely polarized secondary peaks of the V parameter located at distances of −4.5 and +2.7 Å from the line center. If these features are interpreted as manifestations of the magnetic splitting of the line together with its Doppler shift, then the corresponding magnetic field is ≈2.2 × 105 G, and the radial velocity −46 km s−1. Similar spectral manifestations were also found in the active prominence. For comparison with the theory, the spectral features of the Paschen–Baсk effect at magnetic fields up to 100 kG were studied too. It turned out that the theoretical width of the splitting components is relatively small, 0.3 Å, while the width of the observed peaks is sometimes much larger. On the basis of model calculations, it is shown that in some cases an alternative explanation of the observational data is possible, which includes much weaker magnetic fields (5.5–7.1 kG), but significant macroscopic velocities of different signs, at the level of 50–60 km s−1.

Magnetized Black Holes: Interplay between Charge and Rotation

Already in the cornerstone works on astrophysical black holes published as early as in the 1970s, Ruffini and collaborators have revealed the potential importance of an intricate interaction between the effects of strong gravitational and electromagnetic fields. Close to the event horizon of the black hole, magnetic and electric lines of force become distorted and dragged even in a purely electro-vacuum system. Moreover, as the plasma effects inevitably arise in any astrophysically realistic environment, particles of different electric charges can separate from each other, become accelerated away from the black hole or accreted onto it, and contribute to the net electric charge of the black hole. From the point of principle, the case of super-strong magnetic fields is of particular interest, as the electromagnetic field can act as a source of gravity and influence spacetime geometry. In a brief celebratory note, we revisit aspects of rotation and charge within the framework of exact (asymptotically non-flat) solutions of mutually coupled Einstein–Maxwell equations that describe magnetized, rotating black holes.

IXPE detection of polarized X-rays from magnetars and photon mode conversion at QED vacuum resonance

The recent observations of the anomalous X-ray pulsars 4U 0142+61 and 1RXS J170849.0-400910 by the Imaging X-ray Polarimetry Explorer (IXPE) opened up a new avenue to study magnetars, neutron stars endowed with superstrong magnetic fields (B ≳ 1014 G). The detected polarized X-rays from 4U 0142+61 exhibit a 90° linear polarization swing from low photon energies (E ≲ 4 keV) to high energies (E ≳ 5.5 keV). We show that this swing can be explained by photon polarization mode conversion at the vacuum resonance in the magnetar atmosphere; the resonance arises from the combined effects of plasma-induced birefringence and Quantum electrodynamics (QED)-induced vacuum birefringence in strong magnetic fields. This explanation suggests that the atmosphere of 4U 0142 is composed of partially ionized heavy elements and that the surface magnetic field is comparable to or less than 1014 G, consistent with the dipole field inferred from the measured spindown. It also implies that the spin axis of 4U 0142+61 is aligned with its velocity direction. The polarized X-rays from 1RXS J170849.0-400910 do not show such 90° swing, consistent with magnetar atmospheric emission with B ≳ 5 × 1014 G.

Neutron Lifetime Anomaly and Mirror Matter Theory

This paper reviews the puzzles in modern neutron lifetime measurements and related unitarity issues in the CKM matrix. It is not a comprehensive and unbiased compilation of all historic data and studies, but rather a focus on compelling evidence leading to new physics. In particular, the largely overlooked nuances of different techniques applied in material and magnetic trap experiments are clarified. Further detailed analysis shows that the “beam” approach of neutron lifetime measurements is likely to give the “true” β-decay lifetime, while discrepancies in “bottle” measurements indicate new physics at play. The most feasible solution to these puzzles is a newly proposed ordinary-mirror neutron (n−n′) oscillation model under the framework of mirror matter theory. This phenomenological model is reviewed and introduced, and its explanations of the neutron lifetime anomaly and possible non-unitarity of the CKM matrix are presented. Most importantly, various new experimental proposals, especially lifetime measurements with small/narrow magnetic traps or under super-strong magnetic fields, are discussed in order to test the surprisingly large anomalous signals that are uniquely predicted by this new n−n′ oscillation model.

Force-free magnetic flux ropes: String confinement of super-strong magnetic fields and flare energy release

ABSTRACT A new class of force-free solutions for a horizontal magnetic filament with a circular cross-section is found, in which the magnetic field strength on the axis significantly (up to 2–3 orders of magnitude and more) exceeds the strength of the longitudinal external field that keeps the rope from lateral expansion. A weak transverse field leads to a small deviation from the force-free field structure and results in a density deficit and an increase in temperature on the rope axis. The possibility of a flare release of magnetic energy is shown when critical values ​​of the longitudinal electric current density in the filament are reached at which ‘anomalous resistance’ occurs, caused by the development of the current ion-sound plasma instability. It turns out to be much larger than the usual Coulomb resistance. The following values are determined: the scale of the current dissipation region, the electric field strength in it, which significantly exceeds the Dreicer value, and the possible energy of accelerated charged particles (up to hundreds of MeV). The critical density of the longitudinal current at which the plasma turbulence is excited does not depend on the presence of a super-strong field on the flux-rope axis, so that the current density depends only on the electron concentration, temperature, and anomalous conductivity. However, super-strong magnetic fields can manifest themselves in the fact that, in their presence, the excitation of plasma instabilities can occur at sufficiently high electron concentrations. This effect may explain the large number of accelerated particles sometimes observed in solar flares.

Super-strong magnetic field-dominated ion beam dynamics in focusing plasma devices

High energy density physics is the field of physics dedicated to the study of matter and plasmas in extreme conditions of temperature, densities and pressures. It encompasses multiple disciplines such as material science, planetary science, laboratory and astrophysical plasma science. For the latter, high energy density states can be accompanied by extreme radiation environments and super-strong magnetic fields. The creation of high energy density states in the laboratory consists in concentrating/depositing large amounts of energy in a reduced mass, typically solid material sample or dense plasma, over a time shorter than the typical timescales of heat conduction and hydrodynamic expansion. Laser-generated, high current–density ion beams constitute an important tool for the creation of high energy density states in the laboratory. Focusing plasma devices, such as cone-targets are necessary in order to focus and direct these intense beams towards the heating sample or dense plasma, while protecting the proton generation foil from the harsh environments typical of an integrated high-power laser experiment. A full understanding of the ion beam dynamics in focusing devices is therefore necessary in order to properly design and interpret the numerous experiments in the field. In this work, we report a detailed investigation of large-scale, kilojoule-class laser-generated ion beam dynamics in focusing devices and we demonstrate that high-brilliance ion beams compress magnetic fields to amplitudes exceeding tens of kilo-Tesla, which in turn play a dominant role in the focusing process, resulting either in a worsening or enhancement of focusing capabilities depending on the target geometry.

Signatures of superstrong magnetic fields in a limb solar flare from observations of the Hα line

We present signatures of the super-strong magnetic fields of almost 105 Gauss range in the limb solar flare of 14 July 2005 at the altitudes of 5 – 30 Mm during the post-peak phase of the flare. These features follow from the study of the Stokes V profile in the Hα line at large distances of 1.5 up to 4 Å from its center. A reliable circular polarization (till 1%) was found that changes its sign when crossing the line center. The profile of the polarization differs significantly from the intensity gradient profile dI/dλ, which indicates the strong magnetic field mode. If these features are interpreted as manifestations of the Zeeman effect, the corresponding magnetic field strength reaches ∼ 90 kG. Similar spectral manifestations were not found in another bright emission formation on the solar limb, namely in the active prominence of 24 July 1999. Theoretical analysis of the picture of the Zeeman effect for the case of such giant fields shows that the σ components of the Hα line should be quite narrow (∼0.2 Å) due to the Pashen-Back effect, despite the complex picture of the splitting of this line. Since the observed widths of the peaks of the Stokes V profiles are much wider, this may mean a certain dispersion of the magnetic field strengths in the flare, at which the maximum strengths can be even some greater than those indicated above.