Measuring magnetic field vector by stimulated Raman transitions

2016 ◽  
Vol 108 (12) ◽  
pp. 122401 ◽  
Author(s):  
Wenli Wang ◽  
Richang Dong ◽  
Rong Wei ◽  
Jinda Lin ◽  
Fan Zou ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Field Vector ◽  
Magnetic Field Vector ◽  
Raman Transitions ◽  
Measuring Magnetic Field ◽  
Stimulated Raman

3D Magnetovision Scanner as a Tool for Investigation of Magnetomechanical Principles

2009 ◽  
Vol 154 ◽  
pp. 181-186 ◽  
Author(s):  
Jerzy Kaleta ◽  
Daniel Lewandowski ◽  
P. Wiewiórski
Keyword(s):  
Magnetic Field ◽  
Magnetic Materials ◽  
Field Intensity ◽  
Field Vector ◽  
Fatigue Tests ◽  
Measuring System ◽  
Magnetic Field Vector ◽  
Joint Control ◽  
New Generation ◽  
Measuring Magnetic Field

The study was aimed at designing a system for measuring the distribution of magnetic field around different magnetic objects including Smart Magnetic Materials. A new type of 3D camera for monitoring the magnetic field intensity was constructed. The measurement principle is based on internal magnetics properties of materials and the reverse magnetostriction effect (also called the Villari effect). No external magnetizing field is assumed; the entire magnetic effect is due to magnetomechanical principles. A new generation of Honeywell magnetosensors were applied to measure field intensity in 3D. Small size of measurement area (1.5 mm3) allows quasi-local measurement of magnetic field. In the measurement head also Hall probes were alternately used. The aim of this stage of research was to construct the set for measurement of strength of a very weak magnetic field (10 A/m) around the magnetic objects. In scanner construction three axes for displacement in directions consistent with sensor axis were applied, which permits measuring magnetic field vector in geometrical coordination. Specialized software for data acquisition, processing and visualization of magnetic field vector has been written. In preliminary parts of the work magnetic scanner system allows determination of correspondence between mechanical and magnetic quantities. Main applications for this type of system are: reverse magnetostriction and magnetostriction in smart magnetic materials and composites, martensitic transformation induces plastic strain in shape memory alloys, NDT investigation, identification of local plastic deformation and texture of ferromagnetic materials, magnetic polygraphy and others. Measuring system may be used both as an entirely autonomous system as well as an integrated one, also through joint control with a typical mechanical testing systems for static and fatigue tests.

Measurement of Cardiac Magnetic Field Vector

1989 ◽  
pp. 425-428 ◽  
Author(s):  
Y. Sakauchi ◽  
H. Kado ◽  
N. Awano ◽  
N. Kasai ◽  
M. Higuchi ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Field Vector ◽  
Magnetic Field Vector

scholarly journals Evaluation of Murrell’s EKF-Based Attitude Estimation Algorithm for Exploiting Multiple Attitude Sensor Configurations

Sensors ◽  
2021 ◽  
Vol 21 (19) ◽  
pp. 6450
Author(s):  
Sharanabasaweshwara Asundi ◽  
Norman Fitz-Coy ◽  
Haniph Latchman
Keyword(s):  
Magnetic Field ◽  
Time Derivative ◽  
Estimation Algorithm ◽  
Field Vector ◽  
Attitude Estimation ◽  
Magnetic Field Vector ◽  
Sun Sensor ◽  
Satellite Attitude ◽  
Multiple Sensor ◽  
Sensor Suite

Pico- and nano-satellites, due to their form factor and size, are limited in accommodating multiple or redundant attitude sensors. For such satellites, Murrell’s implementation of the extended Kalman filter (EKF) can be exploited to accommodate multiple sensor configurations from a set of non redundant attitude sensors. The paper describes such an implementation involving a sun sensor suite and a magnetometer as attitude sensors. The implementation exploits Murrell’s EKF to enable three sensor configurations, which can be operationally commanded, for satellite attitude estimation. Among the three attitude estimation schemes, (i) sun sensor suite and magnetometer, (ii) magnetic field vector and its time derivative and (iii) magnetic field vector, it is shown that the third configuration is better suited for attitude estimation in terms of precision and accuracy, but can consume more time to converge than the other two.

scholarly journals Improvement of the Helioseismic and Magnetic Imager (HMI) Vector Magnetic Field Inversion Code

2021 ◽  
Vol 923 (1) ◽  
pp. 84
Author(s):  
Ana Belén Griñón-Marín ◽  
Adur Pastor Yabar ◽  
Yang Liu ◽  
J. Todd Hoeksema ◽  
Aimee Norton
Keyword(s):  
Magnetic Field ◽  
Field Vector ◽  
Magnetic Field Vector ◽  
Solar Dynamics Observatory ◽  
Filling Fraction ◽  
Resolution Element ◽  
New Strategy ◽  
Moderate Field ◽  
Solar Dynamics ◽  
Field Strengths

Abstract A spectral line inversion code, Very Fast Inversion of the Stokes Vector (VFISV), has been used since 2010 May to infer the solar atmospheric parameters from the spectropolarimetric observations taken by the Helioseismic and Magnetic Imager (HMI) on board the Solar Dynamics Observatory. The magnetic filling factor, the fraction of the surface with a resolution element occupied by magnetic field, is set to have a constant value of 1 in the current version of VFISV. This report describes an improved inversion strategy for the spectropolarimetric data observed with HMI for magnetic field strengths of intermediate values in areas spatially not fully resolved. The VFISV inversion code has been modified to enable inversion of the Stokes profiles with two different components: one magnetic and one nonmagnetic. In this scheme, both components share the atmospheric components except for the magnetic field vector. In order to determine whether the new strategy is useful, we evaluate the inferred parameters inverted with one magnetic component (the original version of the HMI inversion) and with two components (the improved version) using a Bayesian analysis. In pixels with intermediate magnetic field strengths (e.g., plages), the new version provides statistically significant values of filling fraction and magnetic field vector. Not only does the fitting of the Stokes profile improve, but also the inference of the magnetic parameters and line-of-sight velocity are obtained uniquely. The new strategy is also proven to be effective for mitigating the anomalous hemispheric bias in the east–west magnetic field component in moderate field regions.

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