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1.
The problem to compute the magnetic field above the chromosphere using data of the vector = B t/Bt that gives the projected field direction can be solved with different approximations. The field of direction vectors is, however, not the only field accessible to observations. The Stokes parameters, which are components of the radiation tensor, can be measured at each point of the image plane. The directions of the eigenvectors of the radiation tensor define two mutually orthogonal systems of integral curves in the image plane. These families of curves have singular points, which are generally of different type than those of the vector field. When the morphology of H chromospheric fibrils are used to infer the topology of the magnetic field, a similar problem is met, suggesting that singular points should also be present there.  相似文献   
2.
The magnetic flux longitudinal distribution in the equatorial solar zone has been studied. The magnetic synoptic maps of the Wilcox Solar Observatory (WSO) during Carrington rotations (CRs) 2052–2068 in 2007 and early 2008 have been analyzed. The longitudinal distributions of the area of the zones where the photospheric magnetic field locally enhanced have been constructed for each CR. The obtained distributions indicate that the zones are located discretely and that a clearly defined one narrow longitudinal interval with the maximum flux is present. The longitudinal position of this maximum shifted discretely by ≈130° at an interval of 5.5 ± 0.5 CRs. A longitudinal shift of the zones with an increased magnetic flux multiple of 60° was observed between the hemispheres. In addition, a time shift of ≈2.5 CRs existed between the instants when the position of maximum fluxes in different hemispheres shifted. The established peculiarities of the magnetic flux longitudinal distribution and time dynamics are interpreted as an action of supergiant convection cells. These actions result in that magnetic fields are removed from the generation region through the channels that are formed between such cells at a longitudinal interval of 120°. The average synodic rotation velocity of the considered equatorial channels, through which the magnetic flux emerges, is 13.43° day–1.  相似文献   
3.
Geomagnetism and Aeronomy - The magnetic evolution of the active region of the Sun at the level of the photosphere has been studied. Magnetic synoptic maps of the 2007 Kitt Peak Observatory were...  相似文献   
4.
The nature of structures detected recently on the Sun in soft X rays by I.F. Nikulin (Sternberg Astronomical Institute) and called by him “partings” is discussed. It is shown that these structures are sign-reversal lines for the normal component of the curvature vector of the magnetic lines. Equations describing these lines are derived and models of the corresponding fields calculated.  相似文献   
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6.
The configuration of the solar corona magnetic field has been studied. Data on the position of the K-corona emission polarization plane during the solar eclipses of September 21, 1941; February 25, 1952; and August 1, 2008, were used as an indicator of the magnetic field line orientation. Based on an analysis of these data, a conclusion has been made that the studied configuration has a large-scale organization in the form of a cellular structure with an alternating field reversal. The estimated cell size was 61° ± 6° (or 36° ± 2°) in longitude with a latitudinal extension of 40°?C50° in the range of visible distances 1.3?C2.0 R Sun . A comparison of the detected cellular structure of the coronal magnetic field with synoptic {ie908-1} maps indicated that the structure latitudinal boundaries vary insignificantly within 1.1?C2.0 R Sun . The possible causes of the formation of the magnetic field large-scale cellular configuration in the corona and the conditions for the transformation of this configuration into a two-sector structure are discussed.  相似文献   
7.
The structures called Whitney gathers in the catastrophe theory are not unusual among the various types of chromospheric Hα filaments and coronal helmets. They result from a projection of smooth surfaces onto a plane of the sky. The apices of the helmets can be described as gathers of the surface B r = 0 in the corona (where B r is the magnetic field). Near the limb, Hα filaments are frequently observed as similar types of structures. A model of the B r = 0 surface with sources located inside the Sun ( Bds = 0) is constructed here in this context. Gathers and folds of this surface are shown to be possible in relatively simple fields. Our model computations are supported by the available observational data.  相似文献   
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Geomagnetism and Aeronomy - The evolution of the magnetic configuration in the solar corona is studied. The curvature of the K-corona helmets obtained from an analytical approximation of the...  相似文献   
10.
The problem of the transport and transformation of magnetic fields from the generation zone to the photosphere is studied in this paper. For this purpose, the temporal variations of parameters of bipolar magnetic regions are analyzed based on the magnetic synoptic maps of the Wilcox Solar Observatory (WSO) for the declining phase of cycle 22. A 150-day modulation of the magnetic flux value in bipolar regions and a variation in their rotation velocity with a duration of 80–100 days have been found. Such variations in the parameters are interpreted as a result of action of supergiant and giant convection cells. The magnetic flux from the generation zone emerges through the local channels formed by the supergiant convection cells. From the level of 0.95 RSun, the flux is redistributed by giant cells, which form bipolar magnetic regions on the photosphere.  相似文献   
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