scholarly journals Heliospheric magnetic field polarity inversions driven by radial velocity field structures

2006 ◽  
Vol 33 (14) ◽  
Author(s):  
Simone Landi ◽  
Petr Hellinger ◽  
Marco Velli
Keyword(s):  
Magnetic Field ◽  
Velocity Field ◽  
Radial Velocity ◽  
Field Polarity ◽  
Heliospheric Magnetic Field

scholarly journals Modulation of UK lightning by heliospheric magnetic field polarity

2014 ◽  
Vol 9 (11) ◽  
pp. 115009 ◽  
Author(s):  
M J Owens ◽  
C J Scott ◽  
M Lockwood ◽  
L Barnard ◽  
R G Harrison ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Field Polarity ◽  
Heliospheric Magnetic Field

scholarly journals The global heliospheric magnetic field polarity distribution as seen at Ulysses

2003 ◽  
Vol 21 (6) ◽  
pp. 1377-1382 ◽  
Author(s):  
G. H. Jones ◽  
A. Balogh
Keyword(s):  
Magnetic Field ◽  
Solar Wind ◽  
Solar Activity ◽  
Magnetic Fields ◽  
Current Sheet ◽  
Heliospheric Current Sheet ◽  
Field Polarity ◽  
Heliospheric Magnetic Field ◽  
Interplanetary Magnetic Fields ◽  
Interplanetary Physics

Abstract. The Ulysses spacecraft is in a near-polar solar orbit with a period of 6.2 years. The heliospheric magnetic field polarity detected by Ulysses from its 1992 Jupiter encounter to the current time is presented, following ballistic mapping of the polarity information to the solar wind source surface, at approximately 2.5 solar radii. The spacecraft’s first foray to polar latitudes and first rapid heliolatitude scan occurred in 1994–1995, near a minimum in solar activity. The heliospheric current sheet during this period was confined to low heliolatitudes. In 2000–2001, Ulysses returned in situ data from the same region of its orbit as in 1994–1995, but near to the maximum in solar activity. Unlike at solar minimum, heliospheric current sheet crossings were detected at the spacecraft over a wide heliolatitude range, which is consistent with the reversal of the solar magnetic dipole occurring during solar maximum. Despite complexity in the solar wind parameters during the latest fast latitude scan (McComas et al., 2002), the underlying magnetic field structure appears consistent with a simple dipole inclined at a large angle to the solar rotational axis. The most recent data show the heliospheric current sheet returning to lower heliolatitudes, indicating that the dipole and rotational axes are realigning, with the Sun’s magnetic polarity having reversed.Key words. Interplanetary physics (interplanetary magnetic fields; sources of the solar wind) – Solar physics, astrophysics and astronomy (magnetic fields)

Cosmic-Ray Transport in Heliospheric Magnetic Structures. III. Implications of Solar Magnetograms for the Drifts of Cosmic Rays

2021 ◽  
Vol 922 (2) ◽  
pp. 124
Author(s):  
Andreas Kopp ◽  
Jan Louis Raath ◽  
Horst Fichtner ◽  
Marius S. Potgieter ◽  
Stefan E. S. Ferreira ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Solar Cycle ◽  
Cosmic Rays ◽  
Boundary Conditions ◽  
Large Scale ◽  
Cosmic Ray ◽  
Magnetic Polarity ◽  
Solar Observatory ◽  
Field Polarity ◽  
Heliospheric Magnetic Field

Abstract The transport of energetic particles in the heliosphere is reviewed regarding the treatment of their drifts over an entire solar cycle including the periods around solar maximum, when the tilt angles of the heliospheric current sheet increase to large values and the sign of the magnetic polarity changes. While gradient and curvature drifts are well-established elements of the propagation of cosmic rays in the heliospheric magnetic field, their perturbation by the solar-activity-induced large-scale distortions of dipole-like field configurations and by magnetic turbulence is an open problem. Various empirical or phenomenological approaches have been suggested, but either lack a theory-based motivation or have been shown to be incompatible with measurements. We propose a new approach of more closely investigating solar magnetograms obtained from GONG maps, leading to a new definition of (i) tilt angles that may exceed those provided by the Wilcox Solar Observatory during high activity and of (ii) a “noninteger sign” that can be used to reduce the drifts during these periods as well as to provide a refinement of the magnetic field polarity. The change of sign from A < 0 to A > 0 of solar cycle 24 can be in this way localized to occur between Carrington Rotations 2139 and 2140 in mid 2013. This treatment is fully consistent in the sense that the transport modeling uses the same input data to formulate the boundary conditions at the heliobase as do the magnetohydrodynamic models of the solar wind and the embedded heliospheric magnetic field that exploit solar magnetograms as inner boundary conditions.

Radial Evolution of Inverted Heliospheric Magnetic Field Between 0.3 and 1 AU

2020 ◽  
Author(s):  
Allan Macneil ◽  
Mathew Owens ◽  
Robert Wicks ◽  
Mike Lockwood ◽  
Matthew Lang ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Solar Wind ◽  
Solar Corona ◽  
Radial Velocity ◽  
Statistical Study ◽  
Heliospheric Magnetic Field ◽  
Radial Evolution ◽  
Inner Heliosphere

&lt;p&gt;Local inversions, or &amp;#8216;switchbacks&amp;#8217;, in the heliospheric magnetic field (HMF) have recently been identified as prominent features in the inner heliosphere through observations by Parker Solar Probe. These inversions coincide with spikes in radial velocity, and have been interpreted as possibly being the result of jets originating in the corona. While magnetic inversions with similar properties to these jets have also been observed by Helios around its perihelion of ~0.3 AU, inversions with a range of properties and scales have long been studied at distances of 1 AU and beyond. The processes which form the inversions seen outside of 0.3 AU, and whether they are a result of solar wind formation in the solar corona or the transport of solar wind through the heliosphere, are not clear. We present a statistical study on the occurrence of inverted heliospheric magnetic field using Helios 1 observations spanning heliocentric distances 0.3&amp;#8212;1 AU. The evolution of inversion occurrence allows us to identify probable locations in the heliosphere where inversions may be produced. Based on these results, we make suggestions as to which processes are most likely responsible for inverted HMF observed between 0.3 and 1 AU.&lt;/p&gt;

scholarly journals Heliospheric magnetic field polarity inversions at high heliographic latitudes

1999 ◽  
Vol 26 (6) ◽  
pp. 631-634 ◽  
Author(s):  
A. Balogh ◽  
R. J. Forsyth ◽  
E. A. Lucek ◽  
T. S. Horbury ◽  
E. J. Smith
Keyword(s):  
Magnetic Field ◽  
Field Polarity ◽  
Heliospheric Magnetic Field

On the Configuration of the Magnetic Field of β CrB

1976 ◽  
Vol 32 ◽  
pp. 613-622
Author(s):  
I.A. Aslanov ◽  
Yu.S. Rustamov
Keyword(s):  
Magnetic Field ◽  
Field Strength ◽  
Radial Velocity ◽  
Magnetic Field Strength ◽  
Complex Shape ◽  
Rotation Period ◽  
Field Variation ◽  
Magnetic Field Variation ◽  
Secular Variations ◽  
The Magnetic Field

SummaryMeasurements of the radial velocities and magnetic field strength of β CrB were carried out. It is shown that there is a variability with the rotation period different for various elements. The curve of the magnetic field variation measured from lines of 5 different elements: FeI, CrI, CrII, TiII, ScII and CaI has a complex shape specific for each element. This may be due to the presence of magnetic spots on the stellar surface. A comparison with the radial velocity curves suggests the presence of a least 4 spots of Ti and Cr coinciding with magnetic spots. A change of the magnetic field with optical depth is shown. The curve of the Heffvariation with the rotation period is given. A possibility of secular variations of the magnetic field is shown.

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