摘要:

AbstractA three‐dimensional (non‐axisymmetric) model for the solar mean magnetic field generation is studied. The sources of generation are the differential rotation and mean helicity in the convective shell. The system is described by two equations of the first order in time and the fourth order in space coordinates. The solution is sought for in the form of expansion over the spherical functionYnm. The modes of differentmare separated. A finite‐difference scheme similar to the Peaceman‐Rachford scheme is constructed so to find coefficients of the expansion depending on the time and radial coordinates.It is shown that a mode with a smaller azimuthal numbermis primarily excited. The axisymmetric modem= o describes the 22 year solar cycle oscillations. The modes ofmo have no such periodicity, the oscillate with a period of rotation of the low boundary of the solar convective shell, The solutions which are symmetric relative to the equator plane are excited more easily compared with the antisymmetrical ones.The results obtained are confronted to the observational picture of the non‐axisymmetric large‐scale solar magn

ISSN:0004-6337    

DOI:10.1002/asna.2113060402

出版商:WILEY‐VCH Verlag    

年代:1985

数据来源: WILEY

摘要:

AbstractThe photometrically determined mean surface magnetic fieldsBSneed a revision. None of the stars for whichBScan be measured directly by Zeeman line splitting fulfils the relation between the photometric parameter Δ(V1–G) and the mean surface fieldBS, which is used by NORTH, CRAMERand MAEDERto determineBSfor other B2 – A3 stars. The ratioBeffMax/BSfor stars, which define North's relation, shows unreasonable large va

ISSN:0004-6337    

DOI:10.1002/asna.2113060403

出版商:WILEY‐VCH Verlag    

年代:1985

数据来源: WILEY

摘要:

AbstractDer schon zu den langperiodischen Ap‐Sternen gehörende Stern HD 221568 wurde im Zeitraum 1976 bis 1981 in zehn Spektralbereichen (3450 Å – 7650 Å) beobachtet. Der Stern zeigt typische Rotationslichtkurven mit einer Doppelwelle. Die Eigenschaften der Amplituden‐Wellenlängen‐Beziehung haben Ähnlichkeit mit der einiger kühler kurzperiodischer Ap‐Sterne. Die berechnete Variation des Strahlungsstroms im Sichtbaren deutet auf eine im ultravioletten zu erwartende Variabilität mit gro

ISSN:0004-6337    

DOI:10.1002/asna.2113060404

出版商:WILEY‐VCH Verlag    

年代:1985

数据来源: WILEY

摘要:

AbstractFlare observations in the solar activity complex HR 16862, 16863, 16864 at the end of May 1980 are compared with the structure of force‐free magnetic fields calculated from photospheric magnetograph measurements. A series of homologous flares connected with a δ configuration in HR 16864 was possibly caused by a magnetic neutral sheet. The δ configuration consisted of the large preceding spot of HR 16864 and a small satellite of opposite polarity. All magnetic flux from the satellite is connected to the main spot, and at the outer edge of the satellite, away from the main spot, a magnetic neutral sheet is found. This agrees with the observation that all penumbra was situated between parent spot and satellite, which is typical of such † configurations. It is suggested that the flare productivity of these configurations is generally caused by magnetic neutral sheets at the penumbra‐free outer boundary of the sat

ISSN:0004-6337    

DOI:10.1002/asna.2113060405

出版商:WILEY‐VCH Verlag    

年代:1985

数据来源: WILEY

摘要:

AbstractMultiple wavelength observations of sunspot umbrae can only be expalined by an inhomogeneous, two‐component model for the structure of the umbral transition region and lower corona. The ‘Wroclaw‐Ondrejov sunspot model’ was a first step in this direction. This working model has now been improved using analytic expressions for the atmospheric structure in each component and fitting the free parameters to recent sunspot observations, particularly in EUV lines. The main component has a shallow transition region and a deep‐set corona. The second, ‘active’ component has a vast transition region in relatively cool fine structure elements embedded in the coronal main component. The spatial filling factor of this active component amounts to 5–10% in sunspots with bright EUV plumes, but is is more than ten times smaller in sunspot without such plumes. Observations with high spatial and temporal resolutions are necessary to understand in more detail the basic phy

ISSN:0004-6337    

DOI:10.1002/asna.2113060406

出版商:WILEY‐VCH Verlag    

年代:1985

数据来源: WILEY

ISSN:0004-6337    

DOI:10.1002/asna.2113060407

出版商:WILEY‐VCH Verlag    

年代:1985

数据来源: WILEY

摘要:

AbstractWith the gradual accumulation of experimental data in the solar neutrino experiment of DAVISand collaborators (runs 18–74 for 1970–1982), the question, whether there are time variations of the solar neutrino flux, is of renewed interest. We discuss the mathematical‐numerical methods applied to the statistical analysis of DAVIS' argon‐37 production rate up till now known in the literature. These methods are characterized by the arbitrary arrangement of the DAVISdata in a time series. We perform a certain Fourier transformation for unequally‐spaced time series of the measuring data of the argon‐37 production rate, discuss the discovered periods and give significance criteria with respect to each period. We find that all periods discussed in the literature are contained in our series of periods. Pointing out the more mathematical character of the time series analysis we emphasize the predominant significance of the detec

ISSN:0004-6337    

DOI:10.1002/asna.2113060408

出版商:WILEY‐VCH Verlag    

年代:1985

数据来源: WILEY

ISSN:0004-6337    

DOI:10.1002/asna.2113060409

出版商:WILEY‐VCH Verlag    

年代:1985

数据来源: WILEY

摘要:

AbstractA simplified model of the very early Universe is presented for studying the effects of the GUT phase transition on the cosmic evolution and vice versa. An exact description of a strongly first order phase transition is given. Both inflationary and non‐inflationray solutions are obtained. The cosmological scale factor and the temperature are determined and graphically depicted. The self‐consistency of our simplifying assumptions needed to get analytic solutions are checked. Contrary to expectations spread in the literature, the strongly first order character of the phase transition in itself is found to be insufficient to solve the monopol problem inherent in most GUT cosmolog

ISSN:0004-6337    

DOI:10.1002/asna.2113060410

出版商:WILEY‐VCH Verlag    

年代:1985

数据来源: WILEY

摘要:

AbstractThe Bach‐Einstein equation linearized around Minkowski space‐time is completely solved. The set of solutions depends on three parameters; a two‐parameter subset of it becomes asymptotically flat. In that region the gravitational potential is of the type φ = ‐m/r+ ε exp (‐r/l)mand ε being small parameters.Because of the different asymptotic behaviour of both terms, it became necessary to linearize also around the Schwarzschild solution φ = ‐m/r. The linearized equation resulting in this case is discussed using qualitative methods. The result is that form≤ 2lthe asymptotic behaviour is φ = ‐m/r+ εr−m/lexp (‐r/l) u, and form≧ 2lφ = ‐m/r+ εr−2exp (‐r/l)u, whereuis some bounded function;mis arbitray and ε again small. Further, the relation between the solution of the linearize

ISSN:0004-6337    

DOI:10.1002/asna.2113060411

出版商:WILEY‐VCH Verlag    

年代:1985

数据来源: WILEY