scholarly journals Study of field-aligned current (FAC), interplanetary electric field component (E y ), interplanetary magnetic field component (B z ), and northward (x ) and eastward (y ) components of geomagnetic field during supersubstorm

2017 ◽  
Vol 4 (5) ◽  
pp. 257-274 ◽  
Author(s):  
Binod Adhikari ◽  
Subodh Dahal ◽  
Narayan P. Chapagain
Keyword(s):  
Magnetic Field ◽  
Electric Field ◽  
Interplanetary Magnetic Field ◽  
Geomagnetic Field ◽  
Field Component ◽  
Electric Field Component ◽  
Magnetic Field Component ◽  
Field Aligned Current

scholarly journals A new borehole electromagnetic receiver developed for CSEM methods

2020 ◽  
Author(s):  
Sixuan Song ◽  
Ming Deng ◽  
Kai Chen ◽  
Muer A ◽  
Sheng Jin
Keyword(s):  
Magnetic Field ◽  
Electric Field ◽  
Field Component ◽  
Field Experiments ◽  
Vertical Component ◽  
Electric Field Component ◽  
Detection Accuracy ◽  
Electromagnetic Methods ◽  
Detection Depth ◽  
Field Noise

Abstract. Conventional surface electromagnetic methods have limitations of shallow detection depth and low resolution. In an attempt to increase the detection depth and resolution, borehole-surface electromagnetic methods for electromagnetic three-dimensional observations of ground, tunnels, and boreholes has been developed. Current borehole receivers only measure a single parameter of the magnetic field component, which does not meet the special requirements of controlled source electromagnetic (CSEM) methods. This study proposes a borehole electromagnetic receiver which realizes synchronous acquisition of the vertical electric field component in the borehole and the three-axis orthogonal magnetic field components. This receiver uses Ti electrodes and fluxgates as sensors to acquire electric and magnetic field components. Multi-component comprehensive observation methods that add the electric field component can effectively support the CSEM method, improve detection accuracy, and show broad potentials for detecting deep ore bodies. We conducted laboratory and field experiments to verify the performance of our new borehole electromagnetic receiver. The receiver achieved magnetic field noise less than 6 pT/√Hz at 1 kHz, and the electric field noise floor was approximately 10 nV/√Hz at 1 kHz. The −3 dB electric field bandwidth can reach DC ~ 10 kHz. Results of our experiments support the claim that high-quality CSEM signals can be obtained using this new borehole electromagnetic receiver, and that the electric field component exhibits sufficient advantages for measuring the vertical component of the electric field.

scholarly journals A new borehole electromagnetic receiver developed for controlled-source electromagnetic methods

2021 ◽  
Vol 10 (1) ◽  
pp. 55-64
Author(s):  
Sixuan Song ◽  
Ming Deng ◽  
Kai Chen ◽  
Muer A ◽  
Sheng Jin
Keyword(s):  
Magnetic Field ◽  
Electric Field ◽  
Field Component ◽  
Field Experiments ◽  
Electric Field Component ◽  
Detection Accuracy ◽  
Controlled Source ◽  
Electromagnetic Methods ◽  
Detection Depth ◽  
Field Noise

Abstract. Conventional surface electromagnetic methods have limitations of a shallow detection depth and low resolution. To increase the detection depth and resolution, borehole–surface electromagnetic methods for electromagnetic three-dimensional observations of the ground, tunnels, and boreholes have been developed. Current borehole receivers only measure a single parameter of the magnetic field component, which does not meet the special requirements of controlled-source electromagnetic (CSEM) methods. This study proposes a borehole electromagnetic receiver that realizes synchronous acquisition of the vertical electric field component in the borehole and the three-axis orthogonal magnetic field components. This receiver uses Ti electrodes and fluxgate magnetometers (fluxgates) as sensors to acquire electric and magnetic field components. Multi-component comprehensive observation methods that add the electric field component can effectively support the CSEM method, improve detection accuracy, and exhibit a strong potential for detecting deep ore bodies. We conducted laboratory and field experiments to verify the performance of our new borehole electromagnetic receiver. The receiver achieved a magnetic field noise of less than 6 pTHz-1/2 at 1 kHz, and the electric field noise floor was approximately 20 nVm-1Hz-1/2 at 1 kHz. The −3 dB electric field bandwidth can reach DC −10 kHz. The results of our experiments prove that high-quality CSEM signals can be obtained using this new borehole electromagnetic receiver and that the electric field component exhibits sufficient advantages for measuring the vertical component of the electric field.

scholarly journals Flux Conservation, Magnetohydrodynamic and Force-free Approximations for Relativistically Streaming Plasmas

1978 ◽  
Vol 31 (6) ◽  
pp. 523
Author(s):  
RR Burman
Keyword(s):  
Magnetic Field ◽  
Electric Field ◽  
Field Component ◽  
Equation Of Motion ◽  
Electric Field Component ◽  
Inertial Effects ◽  
The Magnetic Field ◽  
Component Parallel ◽  
Flux Conservation

The purpose of this paper is to clarify the flux conservation, magnetohydrodynamic and force-free approximations, for plasmas whose component species may be relativistically streaming, by paying particular attention to the conditions for their validity and to their interrelationships. All three approximations involve consideration of inertial effects, either in the generalized Ohm law or in the equation of motion of the plasma as a whole. All three imply that the electric field component parallel to the magnetic field is small. The significance of the approximations for pulsar magnetospheric theory is commented on.

scholarly journals NMR-based metabolomics with enhanced sensitivity

RSC Advances ◽  
2021 ◽  
Vol 11 (15) ◽  
pp. 8694-8700
Author(s):  
Kousik Chandra ◽  
Samah Al-Harthi ◽  
Sujeesh Sukumaran ◽  
Fatimah Almulhim ◽  
Abdul-Hamid Emwas ◽  
...  
Keyword(s):  
Electric Field ◽  
Field Component ◽  
Electric Field Component ◽  
Spin Noise ◽  
Enhanced Sensitivity ◽  
Shaped Tube

We combined Spin Noise Tuning Optimum (SNTO) and electric field component-optimized shaped tube to boost sensitivity for NMR-based metabolomics.

ON OPTIMUM PUPIL FIELDS WITH MAXIMUM ELECTRIC FIELD COMPONENT IN FOCUS

2010 ◽  
Vol 19 (01) ◽  
pp. 189-201
Author(s):  
H. P. URBACH ◽  
S. F. PEREIRA ◽  
D. J. BROER
Keyword(s):  
Electric Field ◽  
Field Component ◽  
Optical Axis ◽  
Focal Point ◽  
Longitudinal Component ◽  
Electric Field Component ◽  
Incident Power ◽  
Entrance Pupil ◽  
Maximum Electric Field ◽  
High Na Lens

The field in the entrance pupil of a high NA lens can be optimized such that, for given incident power, the electric field component in a given direction in the focal point is maximum. If the field component is chosen parallel to the optical axis, the longitudinal component is maximized and it is found that the optimum longitudinal component is narrower than the Airy spot. We discuss how this can be used to obtain higher resolution in photolithography when a resist is used that is sensitive to only the longitudinal component. We describe a proposition for realizing such resist.

scholarly journals Mapping of steady-state electric fields and convective drifts in geomagnetic fields – Part 1: Elementary models

2016 ◽  
Vol 34 (1) ◽  
pp. 55-65 ◽  
Author(s):  
A. D. M. Walker ◽  
G. J. Sofko
Keyword(s):  
Magnetic Field ◽  
Steady State ◽  
Electric Field ◽  
Electric Fields ◽  
Magnetic Field Line ◽  
Geomagnetic Field ◽  
Geomagnetic Field Models ◽  
Spatial Derivatives ◽  
Field Lines ◽  
The Magnetic Field

Abstract. When studying magnetospheric convection, it is often necessary to map the steady-state electric field, measured at some point on a magnetic field line, to a magnetically conjugate point in the other hemisphere, or the equatorial plane, or at the position of a satellite. Such mapping is relatively easy in a dipole field although the appropriate formulae are not easily accessible. They are derived and reviewed here with some examples. It is not possible to derive such formulae in more realistic geomagnetic field models. A new method is described in this paper for accurate mapping of electric fields along field lines, which can be used for any field model in which the magnetic field and its spatial derivatives can be computed. From the spatial derivatives of the magnetic field three first order differential equations are derived for the components of the normalized element of separation of two closely spaced field lines. These can be integrated along with the magnetic field tracing equations and Faraday's law used to obtain the electric field as a function of distance measured along the magnetic field line. The method is tested in a simple model consisting of a dipole field plus a magnetotail model. The method is shown to be accurate, convenient, and suitable for use with more realistic geomagnetic field models.

Sign in / Sign up

Export Citation Format

Share Document