scholarly journals Empirical Scaling Laws for Coronal Heating

1983 ◽  
Vol 102 ◽  
pp. 345-361
Author(s):  
Leon Golub
Keyword(s):  
Magnetic Field ◽  
Field Strength ◽  
Solar Corona ◽  
Magnetic Field Strength ◽  
Scaling Laws ◽  
Coronal Heating ◽  
Coronal Loops ◽  
The Sun ◽  
Single Loop

We review the origins and uses of scaling laws in studies of stellar outer atmospheres, with particular emphasis on the properties of coronal loops. The evidence for a fundamental structuring of the Solar corona is reviewed and a discussion of thermodynamic scaling laws is presented. In order to intercompare different theories for coronal formation and heating, it is necessary to recast the theories in terms of observable quantities. As an example, we present a discussion of magnetic field-related heating and scaling laws which can be obtained relating coronal pressure, temperature and magnetic field strength; available data are shown to be consistent with scaling laws obtained in this way. However, some parameters of the theory must be treated as adjustable at the present time and it is necessary to examine data from other stars in order to determine whether these are true parameters in coronal heating. We examine some of the difficulties involved in using unresolved stellar data when dealing with loop atmospheres, by first treating the Sun as an unresolved source. Using the detailed observations now available we examine the limits of applicability of single-loop models. The possibilities and limits of stellar data are then discussed.

scholarly journals Evaluation of the Interplanetary Magnetic Field Strength Using the Cosmic-Ray Shadow of the Sun

2018 ◽  
Vol 120 (3) ◽  
Author(s):  
M. Amenomori ◽  
X. J. Bi ◽  
D. Chen ◽  
T. L. Chen ◽  
W. Y. Chen ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Field Strength ◽  
Interplanetary Magnetic Field ◽  
Magnetic Field Strength ◽  
Cosmic Ray ◽  
The Sun

scholarly journals Multifractal structure of the large-scale heliospheric magnetic field strength fluctuations near 85AU

2004 ◽  
Vol 11 (4) ◽  
pp. 441-445 ◽  
Author(s):  
L. F. Burlaga
Keyword(s):  
Magnetic Field ◽  
Field Strength ◽  
Magnetic Field Strength ◽  
Large Scale ◽  
Solar Maximum ◽  
Multifractal Spectrum ◽  
The Sun ◽  
Heliographic Latitude ◽  
The Mean ◽  
The Magnetic Field

Abstract. During 2002, the Voyager 1 spacecraft was in the heliosphere between 83.4 and 85.9AU (1AU is the mean distance from the Sun to Earth) at 34° N heliographic latitude. The magnetic field strength profile observed in this region had a multifractal structure in the range of scales from 2 to 16 days. The multifractal spectrum observed near 85AU is similar to that observed near 40AU, indicating relatively little evolution of the multifractal structure of the magnetic field with increasing distance in the distant heliosphere in the epoch near solar maximum.

scholarly journals Stretching of the Super-Elastic Double-Helix Geon. Wheeler´s Thermal Geons as Quanta of Heat and Momentum. Bohm´s Diffusion and the Heating of the Solar Corona and Heating of the Earth - Geon Engineering. Milgrom-Verlinde Constant. Mareš - Šesták constant

2020 ◽  
Vol 12 (2) ◽  
pp. 12
Author(s):  
Jiri Stavek
Keyword(s):  
Magnetic Field ◽  
Field Strength ◽  
Solar Corona ◽  
Magnetic Field Strength ◽  
Double Helix ◽  
David Bohm ◽  
The Earth ◽  
Highly Sensitive ◽  
Low Magnetic Field ◽  
The Magnetic Field

In our approach we have combined knowledge of Old Masters (working in this field before the year 1905), New Masters (working in this field after the year 1905) and Dissidents under the guidance of Louis de Broglie and David Bohm. Based on the great works of Julian Schwinger and John Archibald Wheeler we will study properties of geons formed by fusion of two soft x-ray particles (dyons) in the Schwarzschild gravitation core in our Sun at temperature 16 * 106 K. There are now several Teams that are able to achieve this fusion temperature in their special instruments (Tokamak, HL-2M Tokamak, Wendelstein 7-X, NIF, etc.) and to study properties of those formed geons. Thermal geons are with us all the time but they are very deeply hidden in our experiments. We have newly introduced Mareš - Šesták constant as the ratio of geon momentum to heat quantum of geon. The key information to enter into the World of geons was the empirical formula of David Bohm - the very well-known Bohm diffusion. From this formula we have extracted the amplitude, wavelength, frequency, quantum of the geon action, displacement law for geons, etc. It was found that geons are highly sensitive to the magnetic field strength. At a low magnetic field strength, the “inflation of geons” can occur. This effect could explain the Superheating of the Solar corona and the observed Heating of the Earth during two last centuries influenced by the changes in the Earth´s magnetic field. Geon engineering might modify the geon volume through the magnetic field strength. On the other hand, we were stimulated by the works of Mordehai Milgrom and Eric Verlinde and derived the Milgrom-Verlinde constant describing the gravitational field strength leading to the Newtonian gravitational constant on thermodynamic principles. The quantum of the geon momentum might open a new way how to understand gravitational phenomena. Can it be that Nature cleverly inserted geons into our experimental apparatuses and into our very-well known Old Formulae? We want to pass this concept into the hands of Readers of this Journal better educated in the Mathematics, Physics, and Thermodynamics.

scholarly journals On the magnetic field strength in the solar corona

2004 ◽  
Vol 2004 (IAUS223) ◽  
pp. 453-454 ◽  
Author(s):  
A.B. Delone ◽  
G.A. Porfir'eva ◽  
O.B. Smirnova ◽  
G.V. Yakunina
Keyword(s):  
Magnetic Field ◽  
Field Strength ◽  
Solar Corona ◽  
Magnetic Field Strength ◽  
The Magnetic Field

scholarly journals The magnetic field strength in the Large Magellanic Cloud

1991 ◽  
Vol 148 ◽  
pp. 101-102
Author(s):  
M.E. Costa ◽  
P. M. McCulloch ◽  
P. A. Hamilton
Keyword(s):  
Magnetic Field ◽  
Field Strength ◽  
Magnetic Field Strength ◽  
Large Magellanic Cloud ◽  
Radio Pulsar ◽  
Line Of Sight ◽  
The Sun ◽  
A Value ◽  
Rotation Measure ◽  
The Magnetic Field

We have measured a value of 4±5m--2rad for the rotation measure of the radio pulsar PSR0529-66 in the LMC and, after allowing for the dispersion and rotation measures of our Galaxy on the pulsar's line of sight, we deduce that the magnetic field strength in the LMC is in the range 0 to 5μGauss oriented away from the Sun.

Radial Evolution of Coronal Mass Ejections in the Inner Heliosphere: Catalog and Analysis

2020 ◽  
Author(s):  
Tarik Salman ◽  
Reka Winslow ◽  
Noé Lugaz
Keyword(s):  
Magnetic Field ◽  
Field Strength ◽  
Magnetic Field Strength ◽  
Coronal Mass Ejections ◽  
The Sun ◽  
Maximum Magnetic Field ◽  
Venus Express ◽  
Radial Evolution ◽  
Inner Heliosphere

<p>Our knowledge of the properties of Coronal Mass Ejections (CMEs) in the inner heliosphere is constrained by the relative lack of plasma observations between the Sun and 1 AU. In this work, we present a comprehensive catalog of 47 CMEs measured in situ measurements by two or more radially aligned spacecraft (MESSENGER, Venus Express, STEREO, and Wind/ACE). We estimate the CME impact speeds at Mercury and Venus using a drag-based model and present an average propagation profile of CMEs (speed and deceleration/acceleration) in the inner heliosphere. We find that CME deceleration continues past Mercury's orbit but most of the deceleration occurs between the Sun and Mercury. We examine the exponential decrease of the maximum magnetic field strength in the CME with heliocentric distance using two approaches: a modified statistical method and analysis from individual conjunction events. Findings from both the approaches are on average consistent with previous studies but show significant event-to-event variability. We also find the expansion of the CME sheath to be well fit by a linear function. However, we observe the average sheath duration and its increase to be fairly independent of the initial CME speed, contradicting commonly held knowledge that slower CMEs drive larger sheaths. We also present an analysis of the 3 November 2011 CME observed in a longitudinal conjunction between MESSENGER, Venus Express, and STEREO-B focusing on the expansion of the CME and its correlation with the exponential fall-off of the maximum magnetic field strength in the ejecta.</p>

scholarly journals Radial distributions of magnetic field strength in the solar corona as derived from data on fast halo CMEs

2018 ◽  
Vol 4 (1) ◽  
pp. 3-11
Author(s):  
Виктор Файнштейн ◽  
Victor Fainshtein ◽  
Ярослав Егоров ◽  
Yaroslav Egorov
Keyword(s):  
Magnetic Field ◽  
Field Strength ◽  
Solar Corona ◽  
Magnetic Field Strength ◽  
Coronal Magnetic Field ◽  
The Body ◽  
Cone Model ◽  
Radial Profiles ◽  
Halo Cmes ◽  
Slow Wind

In recent years, information about the distance between the body of rapid coronal mass ejection (CME) and the associated shock wave has been used to measure the magnetic field in the solar corona. In all cases, this tech-nique allows us to find coronal magnetic field radial profiles B(R) applied to the directions almost perpendicular to the line of sight. We have determined radial distributions of magnetic field strength along the directions close to the Sun–Earth axis. For this purpose, using the “ice-cream cone” model and SOHO/LASCO data, we found 3D characteristics for fast halo coronal mass ejections (HCMEs) and for HCME-related shocks. With these data we managed to obtain the B(R) distributions as far as ≈43 solar radii from the Sun’s center, which is approximately twice as far as those in other studies based on LASCO data. We have concluded that to improve the accuracy of this method for finding the coronal magnetic field we should develop a technique for detecting CME sites moving in the slow and fast solar wind. We propose a technique for selecting CMEs whose central (paraxial) part actually moves in the slow wind.

scholarly journals A First Spectroscopic Measurement of the Magnetic-field Strength for an Active Region of the Solar Corona

2020 ◽  
Vol 898 (2) ◽  
pp. L34 ◽  
Author(s):  
Ran Si ◽  
Tomas Brage ◽  
Wenxian Li ◽  
Jon Grumer ◽  
Meichun Li ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Active Region ◽  
Field Strength ◽  
Solar Corona ◽  
Magnetic Field Strength ◽  
Spectroscopic Measurement ◽  
The Magnetic Field

scholarly journals CoMStOC: The Coronal Magnetic Structures Observing Campaign

1990 ◽  
Vol 140 ◽  
pp. 20-20
Author(s):  
J.T. Schmelz
Keyword(s):  
Magnetic Field ◽  
Field Strength ◽  
Solar Corona ◽  
Magnetic Field Strength ◽  
Microwave Emission ◽  
X Ray ◽  
Magnetic Structures ◽  
The Magnetic Field ◽  
Microwave Data ◽  
Thermal Bremsstrahlung

The Coronal Magnetic Structures Observing Campaign (CoMStOC) was designed to measure the magnetic field strength and determine its structure in the solar corona. Simultaneous soft X-ray and microwave data separate the contributions of the two dominant microwave emission mechanisms - gyroresonance and thermal bremsstrahlung. Where gyroresonance dominates, the magnetic field can be determined.

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