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On magnetic field gradients in sunspots
Chinese Astronomy, 1980Abstract This paper is devoted mainly to a method of determining the gradient of magnetic fields. Utilizing the numerical solution of the equations of transfer of the Stokes parameters, we have calculated quantities characterizing the asymmetry and the amount of rotation of the wings of the “o” and “e” profiles of the magnetically sensitive line Fe ...
null Ye Shi-hui +2 more
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Magnetic Field Gradients and Coherence-Pathway Elimination
Journal of Magnetic Resonance, Series B, 1995The amount of residual transverse magnetization after the application of a pulsed magnetic-field gradient (PFG) is calculated for a homogeneous volume of interest (VOI) with three orthogonal pairs of sides and for VOIs that deviate from this idealized case. Many of the results can be understood in terms of the Fourier-transform relationship between the
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Particles incident on magnetic field gradients
Journal of Geophysical Research, 1968Trajectory and penetration of single charged particle coming from field free region to boundary of idealized two dimensional magnetic ...
T. E. Stevenson, C. Comstock
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Hardware, Especially Gradient Magnetic Fields
2008I am often asked why I bother to teach about the “nuts and bolts” of the MRI scanner system. After all, with the exception of physicists and engineers who are specifically interested in dealing with and perhaps modifying the hardware components of the scanner, virtually every MR user will leave the upkeep of the system to professional service personnel.
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Vertical gradients of sunspot magnetic fields
Solar Physics, 1983In this paper, we describe results of a Solar Maximum Mission (SMM) guest investigation to determine vertical gradients of sunspot magnetic fields for the first time from coordinated observations of photospheric and transition-region fields. Both the photospheric vector field of a sunspot, derived from observations using the NASA Marshall Space Flight ...
M. J. Hagyard +8 more
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CHAPTER 5. Magnetic Field Gradients
2016Magnetic field gradients are an integral component in all MRI and NMR systems. The first part of this chapter describes the different design methods that can be used to produce gradients with high linearity, high efficiency and low eddy currents. Challenges that have to be faced include heating from the very large currents present in the gradient coils
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Electric Field Gradient Effects on Magnetic Susceptibility
2004Abstract A general expression for the magnetic susceptibility of a molecule in the presence of a time-independent, spatially uniform magnetic field, and a non-uniform electric field with a uniform gradient is discussed. The molecular response can be described by magnetic susceptibility polarizability tensors that depend on the choice of the origin ...
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Fields and gradients in multipolar magnets
Journal of Applied Physics, 1986This paper describes the two-dimensional field generated by an M pole electromagnet of cylindrical symmetry. By individually controlling the currents on each pole, it is possible to rotate the direction of the field around the axis of the cylinder. Gradients of any order can also be generated.
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A unilateral magnet with an extended constant magnetic field gradient
Journal of Magnetic Resonance, 2010Unilateral magnetic resonance (UMR) has become, in different research areas, a powerful tool to interrogate samples of arbitrary size. Numerous designs have been suggested in the literature to produce the desired magnetic field distributions, including designs which feature constant magnetic field gradients suitable for diffusion and profiling ...
Juan C, García-Naranjo +3 more
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Radiofrequency magnetic field gradient echoes have reduced sensitivity to susceptibility gradients
Magnetic Resonance Imaging, 1995The amplitudes of gradient-echoes produced using static field gradients are sensitive to diffusion of tissue water during the echo evolution time. Gradient-echoes have been used to produce MR images in which image intensity is proportional to the self-diffusion coefficient of water. However, such measurements are subject to error due to the presence of
G, Karczmar, J, River, A P, Koretsky
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