scholarly journals INVESTIGATION MAGNETIC FIELD AND ROCK MAGNETISM DIVERSITY OF THE MELNYKOVTCI PLOT OF THE UKRAINIAN SHIELD

2020 ◽  
Author(s):  
M. Reshetnyk ◽  
D. Starokadomsky ◽  
C. Popov ◽  
R. Khomenko
Keyword(s):  
Magnetic Field ◽  
Rock Magnetism ◽  
Residual Magnetization ◽  
Ukrainian Shield ◽  
Southwestern Part ◽  
Scanning Method ◽  
Local Tectonics ◽  
Thermomagnetic Properties ◽  
The Magnetic Field

The magnetic scanning method was used to study the exposed section of the Ukrainian Shield in its southwestern part (Pobuzhie region). The values of induction T of the magnetic field (49750+– 100 nT, not counting on the global field), and the magnetic susceptibility MS indices “in situ” were determined. It was found that the MS values vary in 0 - 50 • 10-3 u.SI, with the presence of single regions of more than 50 • 10-3 u.SI. Not found regular direct correlations and patterns of changes in the indicators MS and T. An attempt has been made to reveal correlations between fluctuations of the magnetic field and MS-differences. The results are interpreted from the standpoint of local tectonics. Samples taken from exposure, were studied for density, hysteresis of thermomagnetic properties, orientation of the residual magnetization.

scholarly journals GEOLOGICAL INFORMATION OF MAGNETIC PROPERTIES OF GRANITOIDS OF THE PRECEMBRIAN BASEMENT OF UKRAINIAN SHIELD (ON THE EXAMPLE OF THE MELNIKOVTSY PLOT)

2021 ◽  
Vol 7 (2(38)) ◽  
pp. 33-41
Author(s):  
M. Reshetnyk ◽  
D. Starokadomsky
Keyword(s):  
Magnetic Field ◽  
Magnetic Properties ◽  
Internal Structure ◽  
Geophysical Methods ◽  
Geological Mapping ◽  
The Body ◽  
Ukrainian Shield ◽  
Scanning Method ◽  
Geological Body ◽  
The Magnetic Field

In Ukraine, there are all possibilities for the development of geophysical methods for solving the problems of mapping the Precambrian foundation, as there is a well-exposed Ukrainian Shield (US). The article shows the possibilities of the magnetic scanning method for geological mapping, on the example of a section composed of granitoids with xenoliths of crystalline shales. The magnetic field and magnetic susceptibility on exposures are «scanned» in detail. Two positive anomalies of the magnetic field with a similar fine internal structure have been identified. The results of the study showed that granitoids have low magnetic properties that do not allow the formation of positive anomalies of the magnetic field. It is assumed that the source of «toothed» positive anomalies of the magnetic field in the studied section of the US can be two parts of one layered geological body — with a rhythmic internal structure composed of crystalline shales. It is possible that the body was awakened by local tectonic processes and torn into parts that are significantly displaced, and even lie almost parallel in the study area.

scholarly journals Principal Component Gradiometer technique for removal of spacecraft-generated disturbances from magnetic field data

2020 ◽  
Author(s):  
Ovidiu Dragoş Constantinescu ◽  
Hans-Ulrich Auster ◽  
Magda Delva ◽  
Olaf Hillenmaier ◽  
Werner Magnes ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Principal Component ◽  
Field Measurements ◽  
Magnetic Field Data ◽  
Service Oriented ◽  
Sensor Configuration ◽  
Time Required ◽  
First Time ◽  
The Magnetic Field

Abstract. In situ measurement of the magnetic field using space borne instruments requires either a magnetically clean platform and/or a very long boom for accommodating magnetometer sensors at a large distance from the spacecraft body. This significantly drives up the costs and time required to build a spacecraft. Here we present an alternative sensor configuration and an algorithm allowing for ulterior removal of the spacecraft generated disturbances from the magnetic field measurements, thus lessening the need for a magnetic cleanliness program and allowing for shorter boom length. The proposed algorithm is applied to the Service Oriented Spacecraft Magnetometer (SOSMAG) onboard the Korean geostationary satellite GeoKompsat-2A (GK2A) which uses for the first time a multi-sensor configuration for onboard data cleaning. The successful elimination of disturbances originating from several sources validates the proposed cleaning technique.

Transport of energetic particles from reconnecting current sheets in flaring corona to the heliosphere

2021 ◽  
Author(s):  
Philippa Browning ◽  
Mykola Gordovskyy ◽  
Satashi Inoue ◽  
Eduard Kontar ◽  
Kanya Kusano ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Energetic Particles ◽  
Transport Processes ◽  
Data Driven ◽  
Current Sheets ◽  
Electrons And Ions ◽  
Data Driven Approach ◽  
Particle Simulations ◽  
The Magnetic Field

<p>In this study, we inverstigate the acceleration of electrons and ions at current sheets in the flaring solar corona, and their transport into the heliosphere. We consider both generic solar flare models and specific flaring events with a data-driven approach. The aim is to answer two questions: (a) what fraction of particles accelerated in different flares can escape into the heliosphere?; and (b) what are the characteristics of the particle populations propagating towards the chromosphere and into the heliosphere?</p><p>We use a combination of data-driven 3D magnetohydrodynamics simulations with drift-kinetic particle simulations to model the evolution of the magnetic field and both thermal and non-thermal plasma and to forward-model observable characteristics. Particles are accelerated in current sheets associated with flaring reconnection. When applied to a specific flare, the model successfully predicts observed features such as the location and relative intensity of hard X-ray sources and helioseismic source locations. This confirms the viability of the approach.</p><p>Using these MHD-particle models, we will show how the magnetic field evolution and particle transport processes affect the characteristics of both energetic electrons and ions in the the inner corona and the heliosphere. The implications for interpretation of in situ measurements of energetic particles by Solar Orbiter and Parker Solar Probe will be discussed.</p><p> </p><p> </p>

scholarly journals Magnetospheric Processes Possibly Related to the Origin of Cosmic Rays

1981 ◽  
Vol 94 ◽  
pp. 373-391
Author(s):  
Gerhard Haerendel
Keyword(s):  
Magnetic Field ◽  
Large Scale ◽  
Small Scale ◽  
Shear Stresses ◽  
Acceleration Process ◽  
Dayside Magnetopause ◽  
Field Lines ◽  
The Magnetic Field ◽  
Auroral Particles

Two processes are discussed which violate the frozen-in condition in a highly conducting plasma, reconnection and the auroral acceleration process. The first applies to situations in which . It plays an important role in the interaction of the solar wind with the Earth's magnetic field and controls energy input into as well as energetic particle release from the magnetosphere. Detailed in situ studies of the process on the dayside magnetopause reveal its transient and small-scale nature. The auroral acceleration process occurs in the low magnetosphere (β « 1) and accompanies sudden releases of magnetic shear stresses which exist in large-scale magnetospheric-ionospheric current circuits. The process is interpreted as a kind of breaking. The movements of the magnetospheric plasma which lead to a relief of the magnetic tensions occur in thin sheets and are decoupled along the magnetic field lines by parallel electric potential drops. It is this voltage that accelerates the primary auroral particles. The visible arcs are then traces of the magnetic breaking process at several 1000 km altitude.

Cleaning magnetometer data using multi sensor configuration

2020 ◽  
Author(s):  
Dragos Constantinescu ◽  
Hans-Ulrich Auster ◽  
Magda Delva ◽  
Olaf Hillenmaier ◽  
Werner Magnes ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Field Measurements ◽  
Sensor Arrangement ◽  
Magnetometer Data ◽  
Service Oriented ◽  
Sensor Configuration ◽  
First Time ◽  
The Magnetic Field ◽  
Magnetic Cleanliness

<p>Measuring the in situ magnetic field using space borne instruments requires either a magnetically clean platform and/or a very long boom for accommodating magnetometers sensors at a large distance from the spacecraft body. This significantly drives up the costs and time for building the spacecraft. Here we present an alternative sensor configuration and an algorithm allowing for ulterior removing of the spacecraft generated disturbances from the magnetic field measurements, thus lessening the need for a magnetic cleanliness program.</p><p>The Service Oriented Spacecraft Magnetometer (SOSMAG) onboard the Korean Geostationary Satellite GEO-KOMPSAT-2A (GK-2A) uses for the first time a multi-sensor configuration for onboard data cleaning. To remove the AC disturbances, a combination of the measurements from sensors placed at different positions from the disturbance sources is processed onboard. Sensor biases due to daily temperature variations are also removed using the specific SOSMAG sensor arrangement. </p><p> </p>

A New Model to Describe the Magnetic Structure of CMEs

2020 ◽  
Author(s):  
Nada Al-Haddad ◽  
Noé Lugaz
Keyword(s):  
Magnetic Field ◽  
Flux Rope ◽  
Challenging Problem ◽  
New Paradigm ◽  
Field Orientation ◽  
Magnetic Field Orientation ◽  
The Past ◽  
Current Paradigm ◽  
The Magnetic Field

<p>The structure of coronal mass ejections (CMEs) has been the center of numerous studies over the past few decades. Defining the magnetic field orientation locally and globally has proven to be a challenging problem, due to the limited nature of observations that we have, as well as our reliance on the current paradigm of highly-twisted flux ropes. Studies suggest that not all CMEs measured <em>in situ </em>fit within the simple twisted and well-organized flux rope topology. Additionally, many of the events that can be well fitted by existing static flux rope models, do not have as simple a structure as that assumed by the models. This is clear from remote observations and multi-spacecraft measurements. With the wealth of data that we have today, as well as the affluence of research and analysis performed over the last 40 years, it is dues time to present an alternative paradigm, that better represents those data. In this work, we discuss this new paradigm and the literature leading to it. </p>

Formation of Fe-Co-Si Structure in Fe and Co Implanted Si Substrate

MRS Advances ◽  
2017 ◽  
Vol 2 (42) ◽  
pp. 2309-2314
Author(s):  
Wickramaarachchige J. Lakshantha ◽  
Satyabrata Singh ◽  
Floyd D. McDaniel ◽  
Bibhudutta Rout
Keyword(s):  
Magnetic Field ◽  
Phase Structure ◽  
Peak Concentration ◽  
Ternary Phase ◽  
Ion Beam ◽  
Substrate Surface ◽  
Beam Direction ◽  
Si Substrate ◽  
The Magnetic Field

ABSTRACTTernary Fe-Co-Si B20 phase structure was formed by implanting Fe and Co ions consecutively into Si(100) substrate at 50 keV energy, each with a fluence of 1.0 × 1017 atoms/cm2 and post-thermal vacuum annealing at 500 oC for 60 minutes. An in-situ magnetic field was used to enhance the formation of the ternary phase in the Si substrate during the implantation process. The magnetic field of 0.05 T was applied perpendicular to the incoming ion beam direction and parallel to the substrate surface to form elongated clusters in the transverse direction of the sample. Prior to the implantation of ions, the implant ions depth profiles were simulated using a dynamic ion-solid interaction code (TRIDYN). The TRIDYN simulation predicted a saturation in the peak concentration of the Fe and Co ions at a fluence of 1.0 × 1017 atoms/cm2. XPS measurement at the peak concentration depth (40 nm) showed the presence of Fe (23 %) and Co (32 %) in the Si matrix. XRD characterization confirmed the presence of stable Fe-Co-Si B20 phase structure in the annealed samples implanted with the in-situ magnetic field.

SOME OBSERVATIONS ON ROCK MAGNETISM

Geophysics ◽  
1958 ◽  
Vol 23 (2) ◽  
pp. 285-298 ◽  
Author(s):  
Lynn G. Howell ◽  
Joseph D. Martinez ◽  
E. H. Statham
Keyword(s):  
Magnetic Field ◽  
Magnetic Material ◽  
Magnetic Susceptibility ◽  
Transition Temperature ◽  
Iron Ore ◽  
Rock Magnetism ◽  
Bedding Plane ◽  
Metamorphic Rocks ◽  
The Magnetic Field ◽  
Red Bed

It seems that in general the plane of maximum magnetic susceptibility lies in the bedding plane for sediments and in the plane of foliation for metamorphic rocks; there is, also, a tendency for the remanent vector to lie in the plane of foliation in the latter. In the case of chemical deposits, the question is raised as to whether the hematite crystal growth is controlled by the magnetic field. Since pure hematite crystals are paramagnetic along the ternary axis, the remanent vector lies in the basal plane perpendicular to this axis, which being the plane of ferromagnetism, is also the plane of maximum susceptibility. We have investigated chemically deposited hematite in the Clinton iron ore of Silurian Age. Although the remanent vector lies close to the plane of maximum susceptibility, this plane, unfortunately, is also the bedding plane. Several other hematite‐bearing formations show a direction of magnetization close to the bedding plane. Measurements of magnetization and susceptibility anisotropy of samples cooled below the transition temperature for hematite have been made with no conclusive results other than indications of the presence of hematite in some cases. Samples from the Hazel formation of pre‐Cambrian Age have been investigated. The planes of maximum susceptibility for this slightly metamorphosed red bed dip at various angles, and thus a system of microfractures containing magnetic material is suggested as a possible explanation. Pole locations for the Clinton iron ore and the Hazel are presented.

scholarly journals Application of in situ digital holography to the study of the effect of a magnetic field on the anodic dissolution of iron in thichloroacetic acid

2006 ◽  
Vol 71 (1) ◽  
pp. 67-73 ◽  
Author(s):  
Xuegeng Yang ◽  
Shenhao Chen ◽  
Chao Wang ◽  
LI. Liang
Keyword(s):  
Magnetic Field ◽  
Acid Solution ◽  
Anodic Dissolution ◽  
Potentiodynamic Polarization ◽  
Trichloroacetic Acid ◽  
Digital Holography ◽  
Polarization Method ◽  
Trichloroacetic Acid Solution ◽  
The Magnetic Field

The effect of a magnetic field on the anodic dissolution of iron in 1.0 mol dm-3 trichloroacetic acid solution was studied by the potentiodynamic polarization method and in situ digital holography. It was found that the magnetohydrodynamic force increased the mass transport, which resulted in a faster anodic dissolution of iron. The effect of the magnetic field was analyzed by holograms and is discussed in terms of the magnetohydrodynamic force.

scholarly journals Effect of Loudspeakers on the In Situ Electric Field in a Driver Body Model Exposed to an Electric Vehicle Wireless Power Transfer System

Energies ◽  
2020 ◽  
Vol 13 (14) ◽  
pp. 3635
Author(s):  
Junqing Lan ◽  
Akimasa Hirata
Keyword(s):  
Magnetic Field ◽  
Field Strength ◽  
Electric Field ◽  
Electric Field Strength ◽  
Electric Vehicle ◽  
Wireless Power ◽  
Body Model ◽  
Maximum Electric Field ◽  
The Magnetic Field

This study computationally evaluates the effect of loudspeakers on the in situ electric field in a driver body model exposed to the magnetic field from a wireless power transfer (WPT) system in an electric vehicle (EV), one with a body made of carbon fiber reinforced plastic (CFRP) and the other made with aluminum. A quasi-static two-step approach was applied to compute the in situ electric field. The computational results showed that the magnetic field distribution generated by the WPT is significantly altered around the loudspeakers, and shows obvious discontinuity and local enhancement. The maximum spatial-average magnetic field strength in the driver’s body was increased by 11% in the CFRP vehicle. It was 2.25 times larger than the reference levels (RL) prescribed in the International Commission of Non-Ionizing Radiation Protection (ICNIRP) guidelines in 2010. In addition, we found that the in situ electric field computed by the line- and volume-averaging methods were stable if the top 0.1% voxels are excluded. The maximum value was well below the basic restriction (BR) of the ICNIRP guidelines. Nevertheless, the presence of the loudspeaker led to increments in the electric field strength in parts of the human body, suggesting the potential influence of permissible transmitting power in the WPT system. The maximum electric field strength in the thigh and buttock with the woofer, increased by 27% in the CFRP vehicle. The arm value was up to 3 times higher than that obtained without the tweeter in the aluminum vehicle. Moreover, this study found that the maximum electric field strength depended on the location of the loudspeaker with respect to the WPT system and the separation from the driver model. Therefore, the loudspeaker should be considered when evaluating the maximum in situ electric field strength in the vehicle body design stage.

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