Electromagnetic Field Pulses Research Articles

The process of superdeep penetration of high-speed metallic particles in solid body

An explanation of the effects arising at the collision of a stream of metal particles with a size of 10–100 microns, moving at a speed of 1–3 km/s, with a solid target is proposed. It is assumed that at the moment of impact on the target, the particle loses some electrons and for some time, due to the presence of an oxide shell, retains a positive charge. The flow of electrons passing through the target at the moment of impact generates an electromagnetic field pulse. A particle with a charge of about 10–9 C, having penetrated into a solid target, presses on the channel wall with a force of about 500 MPa and moves in it under the action of forces caused by the polarization of the target substance. The combination of high pressure and displacement leads to a significant reduction in the particle-wall friction force. The proposed hypothesis, if confirmed, can help find ways to protect electronic devices of spacecraft from impacts from streams of fast dust particles.

О выделении сигнала высокочастотного ЭМ-поля литосферного происхождения: практический аспект

The work is devoted to the practical aspect of separation of pulse-type signals of lithospheric origin in the recorded electromagnetic field by their shape. Experiments on registration of electromagnetic field signals in a wide frequency range have been carried out. In the frequency range from 5 to 20 kHz, pulses consistent with the generalized shape of the pulse of lithospheric origin were detected. Special hardware and software was developed for registration and further processing of electromagnetic field signals in the kilohertz range. With its help, prototypes of pulses of lithospheric origin were identified. An algorithm was proposed and tested, which makes it possible to automatically select pulses similar to the prototype from the entire set of observed data. Field experiments were carried out to isolate pulses of electromagnetic field of lithospheric origin and to determine their energy and quantitative characteristics. Daily variations of the average energy and activity of electromagnetic field pulses of lithospheric origin are revealed.

Comment to the Article “On the Time Integral of Electromagnetic Field” by R.M. Feshchenko (J. Exp. Theor. Phys. 136, 406 (2023))

The article by R. M. Feshchenko (J. Exp. Theor. Phys. 136, 406 (2023)) is devoted to an important issue concerning general properties of electromagnetic field pulses and contains, in particular, critical remarks on our publications (R. M. Arkhipov et al. Quant. Electronics 50, 801 (2020); R. Arkhipov et al., Laser Field Lett. 19, 043001 (2022), and M. V. Arkhipov et al., JETP Lett. 115, 1 (2022)). We reply to these critical remarks and indicate a number of inaccuracies in the aforementioned article.

Measurement of high-power transient electromagnetic pulse field with integrated photonic electric-field sensor

To satisfy certain special requirements for high-power transient electromagnetic pulse (EMP) field measurements, such as high electric field intensity, broad bandwidth, fast rise time, and compact size, here is described an integrated electro-optic sensor. The frequency response in the range from 100 kHz to 12 GHz and the time-domain input/output characteristics of a sub-nanosecond EMP field with an intensity from 5 to 100 kV/m were experimentally characterized. The sensor was demonstrated to measure the time-domain waveform of the ultrawideband EMP field signals with a rise time of 0.35 ns and bandwidth of 1 GHz. In addition, the minimal detectable electric field strength was 16 mV/m/Hz1/2 in the frequency domain, and an intense sub-nanosecond electromagnetic pulse with a peak amplitude of 100 kV/m was observed in the time domain. The reported sensor is expected to be broadly used for intense EMP measurements.

Combined effects of EMP and RF field on emotional behavior in mice.

Recently, concerns about the combined effects of electromagnetic field (EMF) in daily living and occupational environment are rapidly growing. In this study, we investigated the combined effects of 1-week exposure to electromagnetic pulse (EMP) at 650 kV/m for 1,000 pulses and 4.9 GHz radiofrequency (RF) at 50 W/m2 for 1 h/d in male mice. Open field test, tail suspension test and Y-maze were applied to evaluate anxiety, depression-like behaviors and spatial memory ability, respectively. It was found that compared with Sham group, combined exposure to EMP and RF induced anxiety-like behavior, increased the level of serum S100B and decreased the level of serum 5-HT. The results of quantitative proteomic and KEGG analysis showed that the differentially expressed proteins in hippocampus were enriched in Glutamatergic and GABAergic synapse after combined exposure group, which were verified by western blot. In addition, an obvious histological alteration and autophagy-associated cell death were observed in amygdala instead of hippocampus after combined exposure to EMP and 4.9 GHz RF. Combined exposure to EMP and 4.9 GHz RF could induce emotional behavior alteration, which might be associated with Glutamatergic and GABAergic synapse system of hippocampus and autophagy in amygdala.

Penetration of a Heating Electromagnetic Pulse into Plasma in Magnetic Field

Penetration of a heating pulse of quasistationary electromagnetic field into plasma in constant magnetic field directed along its surface was studied. Weakening of electron heat transfer across the magnetic field leads to more efficient heating of electrons near the plasma surface. As a result, the penetration of the field into the plasma decreases, which is accompanied by suppression of the “inverse” skin effect. Inhomogeneous heating of electrons across the magnetic field leads to generation of an electric field strength component orthogonal to both the magnetic field and the direction of temperature gradient. Appearance of the additional field strength component leads to a change in polarization of the reflected pulse. In a sufficiently strong magnetic field, due to suppression of the electron heat flux and less significant effect of the magnetic field on the ion heat flux, a state with large difference of electron and ion temperatures occurs.

Cortical Bone Vibrations Induced by Electromagnetic Field Pulse

The purpose of our study was to test the hypothesis that the electromagnetic pulse (EMP) is capable of inducing mechanical vibrations in bone <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ex vivo</i> . A thin segment of human femur diaphysis (from a tissue repository) suspended on a tensioned line (range <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$T =$ </tex-math></inline-formula> 2.2–123 N) was exposed to EMP (mean <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$B =0.64$ </tex-math></inline-formula> T, <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">dB</i> / <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">dt</i> = 5877 T/s, and the mean <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$B$ </tex-math></inline-formula> -field gradient of 127 T/m) from a solenoid with axis orthogonal to tensioning line, forming a harmonic oscillator whose mechanical vibrations were measured using laser Doppler vibrometry (LDV, noise floor 1 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{m}$ </tex-math></inline-formula> /s). Calculated mean Maxwell stress and Lorentz forces acting on a weakly conducting, diamagnetic bone slice point away from the solenoid for maximum sensitivity of LDV measurement. The electromechanical origin of the LDV signal was confirmed by the order-of-magnitude agreement between calculated (range from 12 to 50 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{m}$ </tex-math></inline-formula> /s) and measured initial bone velocity amplitudes (e.g., <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$35.5~\mu \text{m}$ </tex-math></inline-formula> /s ± <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$7.5~\mu \text{m}$ </tex-math></inline-formula> /s at <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$T =22.2$ </tex-math></inline-formula> N and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$17.7~\mu \text{m}$ </tex-math></inline-formula> /s ± <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$2.5~\mu \text{m}$ </tex-math></inline-formula> /s at <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$T =58.2$ </tex-math></inline-formula> N) and the increasing frequency (25–180 Hz) of decaying oscillations with the square root of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$T$ </tex-math></inline-formula> over the range of line tensions ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$r^{2} =0.978$ </tex-math></inline-formula> , <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$p &lt; 10^{-4}$ </tex-math></inline-formula> , and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$n =17$ </tex-math></inline-formula> ). Theory and experiment show that magnetic field impulses are capable of exerting measurable mechanical forces on bone <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ex vivo</i> . The results raise an interesting question if the electromechanical effect could be sufficiently large to contribute to bone remodeling, reportedly sensitive to vibration amplitudes as small as 1 nm, and considering long duration of orthopedic therapy using repetitive EMP (months).

Theoretical Analysis and Experimental Verification of Polytetrafluoroethylene Surface Flashover from Electrostatic Electromagnetic Pulse Field

Theoretical Analysis and Experimental Verification of Polytetrafluoroethylene Surface Flashover from Electrostatic Electromagnetic Pulse Field

Numerical modelling of passive electroseismic surveying

SUMMARY This work reports numerical modelling of electroseismic conversions when the electric field source originates in the atmosphere. Layered structures of conductivity anomalies yield rotated electric fields at reservoir depths as large as source fields at the surface. Active-source electroseismic field tests imaged reservoirs 1800 m deep. However, the required high-power, dipole sources mediate against these methods finding practical application in hydrocarbon exploration. We extend previous research by considering the potential for using environmental electric fields to create useful electroseismic conversions. World-wide lightning strikes induce time-dependent electric fields in the atmosphere. In the frequency band appropriate for seismic surveying, 1–100 Hz, electromagnetic field pulses occur at a rate of 10–100 pulses per second. These pulses create horizontal electric fields in the earth’s surface that induce electric currents in the subsoil. Those currents preferentially channel through high-conductivity layers. Charge accumulates at the termini of conducting layers. That charge accumulation induces galvanic currents. Vertical galvanic currents propagate to depth where they generate propagating seismic waves at gradients in electrical properties, such as conductivity gradients at reservoirs. We use 2-D numerical simulations on three different, layered-earth models to estimate the seismic amplitudes generated by passive fields. The modelling shows that the transverse magnetic fields can induce potentially useful vertical electric fields at depth. The generated seismic amplitudes at the top of the reservoir are sensitive to the oil content of the reservoir, the frequency of the primary electric field, the geometry of the conducting layers and various material properties. Finally, a hypothetical laterally complex reservoir configuration was tested which confirms the mentioned results and additionally shows the ability of the proposed method to delineate water–oil contacts.

Principle of operation and testing the machine for processing plant raw materials in the fermentation and pre-sowing treatment of seeds with a pulsed electric field

The article describes a device that converts mains voltage into the electromagnetic pulse fields of various frequencies. The device differs from the existing ones by a number of improvements, simple technical design, safety for service personnel and the environment, and low energy consumption. The methods for using the device for pre-sowing seed treatment with the aim of increasing sowing and yielding qualities, as well as suppressing pathogenic mycoflora, processing plant raw materials, in particular teas, medicinal herbs during fermentation are presented. In the fermented material, improved taste and organoleptic properties, weak aftertaste of plant raw materials and no unpleasant odor were observed.

Time domain analysis of impulse electromagnetic field at the interface of two media

Background. Ultrashort pulses of electromagnetic field are widely used in construction, archeology and demining, etc., by constructing effective georadars of the underlying surface, but theoretical study of physical processes of irradiation of medium is had a limit range of simplified model problems, usually in frequency domain. Therefore, the solutions of the problems of penetration of a pulsed wave with arbitrary time dependence into material medium are of special importance for understanding the possibilities and limitations of georadar’s study. Objectives. To obtain the analytical solution in time domain of the problems of reflection and propagation of a impulse electromagnetic wave through the interface of two media, which is the first model approximation to the description of physical processes that occur during operation of pulsed ultrawideband radar. Materials and methods. The problem of irradiation by nonstationary electric field of a lossless medium with a given permittivity is solved analytically by application of evolutionary approach. It consists in solving of Cauchy’s problem for the second-order partial differential equation Klein–Gordon type with respect to evolutionary coefficients. The components of the electromagnetic field in free space are found by integration by spectral parameters and summation by angular modes with appropriate combinations of basis functions. Results. Cauchy’s problems for differential equations that describe the behavior of reflected and refracted waves are solved. The electrical transverse components of the reflected and refracted waves as a function of time on the longitudinal axis were found for the case of irradiation with the step-like time dependence. Graphs of dependence of electric components on time and coordinates are plotted and analyzed. Conclusion. The phenomenon of an electromagnetic missiles in the medium that was irradiated by a pulsed electromagnetic wave of ultrashort duration was demonstrated for the first time. The obtained results can be generalized for the case of an arbitrary impulse by the Duhamel’s integral method. In addition, the electric field for observation point that do not lie on the longitudinal axis can be considered. An even more interesting continuation of the researches in terms of energy analysis is the study of the behavior of longitudinal electric and transverse magnetic components.

A Highly Sensitive and Miniature Optical Fiber Sensor for Electromagnetic Pulse Fields.

The detection of an electromagnetic pulse (EMP) field is of great significance in determining the field environment of tested equipment in small spaces. Finger-shaped miniature optical fiber sensors for electromagnetic pulse field measurement were designed. The antenna of a weak field sensor was integrated with a shielding shell, and the wire welded at the direct electro-optic converting circuit connected to an optical fiber through special structure and circuit design was taken as the antenna of a strong field sensor. Measurements in the time domain and frequency domain had been carried out for the two sensors. Experiment results demonstrate that the weak field sensor and the strong field sensor have flat responses from 100 kHz to 1 GHz with a variation of 2.3 dB and 2.9 dB, respectively, and the EMP waveform detected by the sensors agrees well with the applied standard square wave. Moreover, the strong field sensor exhibits linear responses from 645 V/m to 83 kV/m. The resolution of the weak field sensor is as low as 13 V/m. The result indicated that the designed sensors had good performance.

Research on calibration method of uniformity of radiation interference field of intense electromagnetic pulse

With the rapid development of electronic and electrical products, the working frequency of ite products is higher and higher, the influence frequency range of interference between electronic products is also expanding, the test frequency range of radiation anti-interference is improving, at the same time, more and more attention is paid to the requirements of radiation anti-interference test site. At present, the uniformity of radiation field is mainly realized by single point multiple test, which will inevitably lead to the measurement error due to the time-varying characteristics of the radiation signal itself; In addition, the test time is greatly increased and the test efficiency is low. In order to solve these problems, this paper designs a device which can realize multi-point test at one time and can automatically adjust the test area. The simulation shows that the device can meet the requirement of 9point uniformity test of radiation field in 500mm × 500mm ~ 1500mm × 1500mm area. On this basis, experiments are carried out in 1000mm × 1000mm test area for 1.35GHz and 2.88GHz. The experiments show that the test device can meet the requirement of 9point uniformity test and greatly improve the test efficiency and automation.

Study of a TGF Associated With an Elve Using Extremely Low Frequency Electromagnetic Waves

AbstractA terrestrial gamma‐ray flash (TGF) associated with an Elve was recently reported by the Atmosphere‐Space Interactions Monitor (ASIM) (Neubert et al., 2020, https://doi.org/10.1126/science.aax3872). An extremely low frequency electromagnetic field pulse coinciding with this event was detected by two stations of our World Extremely Low Frequency (ELF) Radiolocation Array (WERA) project from a distance of more than 10,000 km. The recorded signal allowed us to radiolocate the source, determine its polarity, and calculate the charge moment of the associated atmospheric discharge. Our analysis shows that this TGF was associated with a powerful discharge that had a positive polarity and the charge moment p ≈ 125 C·km.

Joint Effect of the Dipole–Dipole Interaction and Constant Dipole Moment on the Shape of the Field Pulse without an Envelope

An integrable model is proposed for a two-level medium with a constant dipole moment, which describes the evolution of electromagnetic field pulses without an envelope with account for the dipole–dipole interaction. In the nearest neighbor approximation, this interaction is taken into account in the form of quadratic dispersion. It is found that such a generalization of the reduced Maxwell–Bloch equations preserves the complete integrability. It is shown using the obtained exact soliton solutions as examples that the joint effect of quadratic dispersion and the constant dipole moment has a number of unique features and provides new opportunities for controlling the shape of field pulses. In particular, it is found that the shape and amplitude of a field pulse depend on the signs of the dipole–dipole interaction as well as on the sign of the constant dipole moment.

Monte Carlo Simulation Based Uncertainty Analysis of Coupling Currents in HEMP Field Tests

In high-altitude electromagnetic pulse (HEMP) field tests, coupling currents under a given illuminated electromagnetic field are important to the design of electronic systems and electromagnetic (EM) shielding. Compared to calculating the arithmetic average (AA) of the amplitude of coupling currents, reference field normalization (RFN) method is a data processing method of HEMP field tests studied in this article. In this method, a reference field is introduced and measured during each repeated illumination of the HEMP field test to minimize the impact of deviations of the illuminated EM field produced by a HEMP simulator. To evaluate the RFN method, uncertainty analysis is carried out. Then the uncertainty and relative error are calculated and compared between the RFN method and the AA method by the coupling currents data both from Monte Carlo method and real test. The results show that the RFN method has a better performance compared to the AA method both from the aspect of uncertainty and relative error.

Few-cycle solitons in a dispersive medium with a permanent dipole moment.

An integrable model of a two-level medium with a permanent dipole moment (PDM) is proposed. The model describes the evolution of electromagnetic field pulses beyond the slow envelope approximation. The dipole-dipole interaction is taken into account in the approximation of the nearest neighbors in the form of a quadratic dispersion. It is found that such a generalization of the reduced Maxwell-Bloch equations is completely integrable. Breather solutions are derived. These solutions are used to study the combined influence of the quadratic dispersion and PDM. It is found that the model possess a number of unique features, which give possibilities for controlling the shape of field pulses. In particular, it is found that the shape and amplitude of the field pulse depends on both the signs of the dipole-dipole interaction and the sign and value of the permanent dipole moment.

Test method of pulse response characteristics for conductive switching materials induced by electromagnetic pulse field

Test method of pulse response characteristics for conductive switching materials induced by electromagnetic pulse field

Scattering of Attosecond Electromagnetic Field Pulses by Atomic and Molecular Anions Including the Magnetic Field Component

Scattering of an attosecond electromagnetic field pulse by atomic and molecular anions is considered in the sudden perturbation approximation. In the interaction with anions, the effect of the magnetic field of the incident pulse is considered. The inclusion of the magnetic component of the ultrashort pulse leads to new results in the scattering spectra for atomic and molecular anions. Analytic dependences of the partial spectrum on frequency are obtained. It is shown that during scattering, the second harmonic is generated, which makes it possible to determine the type of anions and the spatial orientation of molecular anions.

Experimental analysis of electromagnetic pulse effects on engine fuel electronic control system

In this paper, the fuel electronic control system of the engine as an engine control process is designed and constructed to provide the fuel adjustment function of the aero-engine. Then, the electromagnetic pulse (EMP) experiment is established by exposing it to electromagnetic field pulses of the bounded-wave simulator. Now, the damage threshold is also determined. At the same time, the induced differential voltage and common current signals are measured through the printed circuit board (PCB) port, which is necessary to cause a specific microprocessor to fail. The wavelet transform is employed to establish a time-frequency method to process the induced voltage signal. The susceptible frequency areas and coupling energy distribution are applied to the speed acquisition system. Their characteristics are employed to propose a new electromagnetic interference decrease method in both time and frequency domain. This method could be considered as a useful tool for studying the electromagnetic pulse coupling interference.