Zobrazeno 1 - 10
of 137
pro vyhledávání: '"Schmitt, Dieter"'
A new simple dynamo model for stellar activity cycle is proposed. By considering an inhomogeneous mean flow effect on turbulence, it is shown that turbulent cross helicity (velocity--magnetic-field correlation) should enter the expression of turbulen
Externí odkaz:
http://arxiv.org/abs/1601.06348
Publikováno v:
Europhysics Letters 104:49001, November 2013
Planetary and stellar magnetic fields are thought to be sustained by helical motions ($\alpha$-effect) and, if present, differential rotation ($\Omega$-effect). In the Sun, the strong differential rotation in the tachocline is responsible for an effi
Externí odkaz:
http://arxiv.org/abs/1402.0343
We investigate the relations between tachocline-based dynamos and the surface flux transport mechanisms in stars with outer convection zones. Using our combined models of flux generation and transport, we demonstrate the importance of the buoyant ris
Externí odkaz:
http://arxiv.org/abs/1211.1414
Publikováno v:
Astron. Nachr., 328, 1111-1113 (2007)
We present a combined model for magnetic field generation and transport in cool stars with outer convection zones. The mean toroidal magnetic field, which is generated by a cyclic thin-layer alpha-omega dynamo at the bottom of the convection zone is
Externí odkaz:
http://arxiv.org/abs/1111.2453
To reproduce the weak magnetic field on the polar caps of the Sun observed during the declining phase of cycle 23 poses a challenge to surface flux transport models since this cycle has not been particularly weak. We use a well-calibrated model to ev
Externí odkaz:
http://arxiv.org/abs/1104.4183
We have used semi-synthetic records of emerging sunspot groups based on sunspot number data as input for a surface flux transport model to reconstruct the evolution of the large-scale solar magnetic field and the open heliospheric flux from the year
Externí odkaz:
http://arxiv.org/abs/1102.1270
We use the historic record of sunspot groups compiled by the Royal Greenwich Observatory together with the sunspot number to derive the statistical properties of sunspot group emergence in dependence of cycle phase and strength. In particular we disc
Externí odkaz:
http://arxiv.org/abs/1102.1266
The Sun and other cool stars harbouring outer convection zones manifest magnetic activity in their atmospheres. The connection between this activity and the properties of a deep-seated dynamo generating the magnetic flux is not well understood. By em
Externí odkaz:
http://arxiv.org/abs/1102.0569