scholarly journals In-Situ Measurement of Electrical-Heating-Induced Magnetic Field for an Atomic Magnetometer

Sensors ◽  
2020 ◽  
Vol 20 (7) ◽  
pp. 1826 ◽  
Author(s):  
Jixi Lu ◽  
Jing Wang ◽  
Ke Yang ◽  
Junpeng Zhao ◽  
Wei Quan ◽  
...  

Electrical heating elements, which are widely used to heat the vapor cell of ultrasensitive atomic magnetometers, inevitably produce a magnetic field interference. In this paper, we propose a novel measurement method of the amplitude of electrical-heating-induced magnetic field for an atomic magnetometer. In contrast to conventional methods, this method can be implemented in the atomic magnetometer itself without the need for extra magnetometers. It can distinguish between different sources of magnetic fields sensed by the atomic magnetometer, and measure the three-axis components of the magnetic field generated by the electrical heater and the temperature sensor. The experimental results demonstrate that the measurement uncertainty of the heater’s magnetic field is less than 0.2 nT along the x-axis, 1.0 nT along the y-axis, and 0.4 nT along the z-axis. The measurement uncertainty of the temperature sensor’s magnetic field is less than 0.02 nT along all three axes. This method has the advantage of measuring the in-situ magnetic field, so it is especially suitable for miniaturized and chip-scale atomic magnetometers, where the cell is extremely small and in close proximity to the heater and the temperature sensor.

2020 ◽  
Author(s):  
Ovidiu Dragoş Constantinescu ◽  
Hans-Ulrich Auster ◽  
Magda Delva ◽  
Olaf Hillenmaier ◽  
Werner Magnes ◽  
...  

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.


2021 ◽  
Author(s):  
Philippa Browning ◽  
Mykola Gordovskyy ◽  
Satashi Inoue ◽  
Eduard Kontar ◽  
Kanya Kusano ◽  
...  

<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>


2008 ◽  
Vol 587-588 ◽  
pp. 313-317
Author(s):  
D.C. Leitão ◽  
I.G. Trindade ◽  
R. Fermento ◽  
João P. Araújo ◽  
S. Cardoso ◽  
...  

In this work, a study of the sensitivity enhancement of spin valve sensors, when located in close proximity to magnetic flux guides, is presented. The magnetoresistance (MR) of spin-valve sensors, lithographically patterned into stripes with lateral dimensions, (length) l = 500 µm, (width) wsensor = 1, 2, 6 µm and placed near one/two Co93.5Zr2.8Nb3.7 (CZN) magnetic flux guide, is characterized at room temperature. CZN has a high permeability that together with a defined microstructured shape, is able to concentrate the magnetic flux in a small area, leading to an increase in sensor's sensitivity. The magnetic field amplification is estimated by comparison of sensor sensitivity with/without magnetic flux guides, in the linear operation range, and studied as a function of different parameters. Besides an enhancement in sensitivity, sensors also exhibit an important increase in the hard axis coercivity and a shift from MR(H=0) = 0.5, both attributed to the magnetic flux guides. Amplification factors of the order of 20 are observed..


2020 ◽  
Vol 7 (2) ◽  
pp. 166-184
Author(s):  
Agustín Udías, S.J.

Athanasius Kircher paid special attention to magnetism, more specifically terrestrial one, in his work Magnes sive de arte magnetica. Other Jesuits of his time, such as Garzoni and Cabeo, also wrote on this subject. Kircher studied in particular magnetic declination and its possible use to determine geographical longitudes. At his time, this was an important subject for long sea journeys. First, he collected a large number of observations of magnetic declination from different sources in three tables and two lists with a total of 518 values, among them forty-three made by Jesuits. Kircher proposed that a magnetic map could be made based on these observations, but he did not do it. From Kircher’s observations a map of magnetic declination has been drawn and it is presented here. Kircher discussed the causes of declination and presented a model for the origin of the magnetic field of the Earth, which differed from that proposed by Gilbert. Kircher finally considered magnetism as a cosmic force with its origin in God.


1981 ◽  
Vol 94 ◽  
pp. 373-391
Author(s):  
Gerhard Haerendel

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.


Geophysics ◽  
1970 ◽  
Vol 35 (2) ◽  
pp. 331-336 ◽  
Author(s):  
Saurabh K. Verma ◽  
Rishi Narain Singh

Analytic expressions for the quasi‐static electromagnetic response of a sphere in presence of unit‐step and ramp‐type time varying magnetic fields are derived. The conductivity inside the sphere is assumed to vary linearly with radius, i.e. [Formula: see text], where ρ is radial coordinate, [Formula: see text] is a constant and a is the radius of sphere. Curves showing the decay of the magnetic field for both types of fields are presented. In the case of ramp‐type applied magnetic field, the magnitudes of maxima of the induced magnetic field are found to decrease with increase in the rise time of the applied field and, hence, exciting pulses having small values of rise time should be used. It is believed that the analysis will be useful in the geoelectric exploration for highly conducting mineral deposits.


2020 ◽  
Author(s):  
Dragos Constantinescu ◽  
Hans-Ulrich Auster ◽  
Magda Delva ◽  
Olaf Hillenmaier ◽  
Werner Magnes ◽  
...  

<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>


2020 ◽  
Author(s):  
Nada Al-Haddad ◽  
Noé Lugaz

<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>


MRS Advances ◽  
2017 ◽  
Vol 2 (42) ◽  
pp. 2309-2314
Author(s):  
Wickramaarachchige J. Lakshantha ◽  
Satyabrata Singh ◽  
Floyd D. McDaniel ◽  
Bibhudutta Rout

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.


2011 ◽  
Vol 7 (S283) ◽  
pp. 418-419
Author(s):  
Marcelo L. Leal-Ferreira ◽  
Wouter H. T. Vlemmings ◽  
Philip J. Diamond ◽  
Athol Kemball ◽  
Nikta Amiri ◽  
...  

AbstractDuring the transition from an AGB star to a planetary nebula, a large number of low/intermediate initial mass stars loses its spherical symmetry. The process responsible for that change of morphology is, so far, not well understood. The candidates responsible for shaping these objects are (i) a companion to the star (binary/heavy planet) and its tidal forces, (ii) disk interaction and (iii) magnetic fields - or a combination of these. In particular a binary induced magnetic field is a promising option. To study this we observed the polarization of H2O masers in the known binary pre-Planetary Nebula (pPN) OH231.8+4.2. Our results show a magnetic field B|| of ~45 mG is present in the H2O maser region of this pPN.


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