ISSN:0004-6337    

DOI:10.1002/asna.2113090302

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

摘要:

AbstractA photographic photometry inUwas performed for 288 galaxies in the central field of the Coma cluster of galaxies.

ISSN:0004-6337    

DOI:10.1002/asna.2113090303

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

ISSN:0004-6337    

DOI:10.1002/asna.2113090304

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

ISSN:0004-6337    

DOI:10.1002/asna.2113090305

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

摘要:

AbstractIn two theories involving continuous creation higher order curvature terms are added to the field equations. At high gravitational curvatures the creation of matter depends critically on these extra terms.

ISSN:0004-6337    

DOI:10.1002/asna.2113090306

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

ISSN:0004-6337    

DOI:10.1002/asna.2113090308

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

摘要:

AbstractThe production of entropy is calculated in a Friedman Universe governed by a non‐conservative gravitational theory permitting the creation of matter. The calculation has two motivations, the first is that it represents a mechanism to generate the large entropy per baryon observed, and secondly, it simulates the ten dimensional mechanism for entropy production by the out‐of‐equilibrium condition between massive string modes and massless modes with the added condition of energy non‐conservative grav

ISSN:0004-6337    

DOI:10.1002/asna.2113090309

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

摘要:

AbstractSome observational data of the sample of the magnetic chemically peculiar stars (MCP stars) are investigated statistically. For the MCP stars of spectral types later than A2 both the frequency distribution and theR⋅ sini‐values suggest the existence of a linear relation between stellar diameter and rotation period. The MCP stars of spectral types earlier than B9 show an overpopulation of smallR⋅ siniwhich may indicate the existence of a second group with smaller radius in this sample. The equatorially symmetric rotator is used as the magnetic model. With respect to its temporal behaviour the effective magnetic field is separated into dipolar and quadrupolar contribution. Both signs of the axisymmetric quadrupole moment appear with equal frequency. The dipole moment which produces the amplitude of theBeff(t) curve forms for longer periods two groups which are separated by a distinct gap. Both of the groups exhibit magnetic fields which are the stronger the greater the stellar radius is, contrary to what is expected for frozen‐in fields. The dominance of magnetic curves without polarity reversal for longer‐period stars is in accordance with predictions of the dyna

ISSN:0004-6337    

DOI:10.1002/asna.2113090310

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

ISSN:0004-6337    

DOI:10.1002/asna.2113090311

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

摘要:

AbstractThe mean electromotive force and the turbulent stress tensor are derived for an inhomogeneously turbulent conducting fluid under global rotation. The influence of the mean magnetic field on microscale turbulence is taken into account. As a result, the coefficients of magnetic field generation and sources of differential rotation are now functions of the magnetic field; i.e. nonlinear effects are involved. Only nonlinear corrections quadratic in the magnetic field are included (weak nonlinearity). These corrections reduce the $aL‐effect of the $aL$OM‐dynamo for both slow and rapid rotation. Some astrophysical implications are discussed. It is suggested that observed torsional oscillations of the Sun may be brought about by cyclic variations of the magnetic corrections to theA‐effect of differential rotation over the solar activity

ISSN:0004-6337    

DOI:10.1002/asna.2113090312

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY