scholarly journals Inflationary susceptibilities, duality, and large-scale magnetic field generation

2013 ◽  
Vol 88 (8) ◽  
Author(s):  
Massimo Giovannini
Keyword(s):  
Magnetic Field ◽  
Large Scale ◽  
Magnetic Field Generation ◽  
Field Generation ◽  
Large Scale Magnetic Field

scholarly journals HIGH RESOLUTION SPECTROPOLARIMETRY OF THE SOLAR TWINS

2012 ◽  
Vol 18 ◽  
pp. 63-66
Author(s):  
THARCISYO DUARTE ◽  
J. D. DO NASCIMENTO
Keyword(s):  
Magnetic Field ◽  
High Resolution ◽  
Large Scale ◽  
Solar Magnetic Field ◽  
Physical Parameters ◽  
Magnetic Field Generation ◽  
Field Generation ◽  
Large Scale Magnetic Field ◽  
New Generation ◽  
Dynamo Process

The study of solar twins offers a unique opportunity to investigating the solar magnetic field over longer timescales. Supported by the new generation of stellar spectropolarimeters (ESPaDOnS@CFHT, NARVAL@TBL), we are able to measure the large-scale magnetic field solar twins. Studying the behavior of solar magnetic field, we are able to learn about the mechanisms of magnetic field generation in the dynamo process. Besides convection, various physical parameters affect the dynamo operation, in particular the rotation and mass. We collected signature of the stellar large-scale magnetic field for solar twins and we present here a analysis of seven candidates.

scholarly journals LARGE-SCALE MAGNETIC FIELD GENERATION VIA THE KINETIC KELVIN-HELMHOLTZ INSTABILITY IN UNMAGNETIZED SCENARIOS

2012 ◽  
Vol 746 (2) ◽  
pp. L14 ◽  
Author(s):  
E. P. Alves ◽  
T. Grismayer ◽  
S. F. Martins ◽  
F. Fiúza ◽  
R. A. Fonseca ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Large Scale ◽  
Helmholtz Instability ◽  
Magnetic Field Generation ◽  
Field Generation ◽  
Large Scale Magnetic Field

scholarly journals Stationary Turbulent Dynamo as Spontaneous Symmetry Breaking

1993 ◽  
Vol 157 ◽  
pp. 237-241
Author(s):  
M. Hnatich
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Symmetry Breaking ◽  
Spontaneous Symmetry Breaking ◽  
Large Scale ◽  
Magnetic Field Generation ◽  
Field Generation ◽  
Motion Energy ◽  
Turbulent Dynamo ◽  
Large Scale Magnetic Field

The large-scale magnetic field generation by the turbulent motion energy, known as turbulent dynamo [1], is perspective candidate to explain the observed stationary magnetic fields of cosmic objects.

scholarly journals Sun-like Stars: magnetic fields, cycles and exoplanets

2015 ◽  
Vol 11 (A29A) ◽  
pp. 360-364
Author(s):  
Rim Fares
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Large Scale ◽  
Observational Constraints ◽  
The Sun ◽  
Field Generation ◽  
Large Scale Magnetic Field ◽  
Planetary Orbits ◽  
Activity Cycles ◽  
Magnetic Cycles

AbstractIn Sun-like stars, magnetic fields are generated in the outer convective layers. They shape the stellar environment, from the photosphere to planetary orbits. Studying the large-scale magnetic field of those stars enlightens our understanding of the field properties and gives us observational constraints for field generation dynamo models. It also sheds light on how “normal” the Sun is among Sun-like stars. In this contribution, I will review the field properties of Sun-like stars, focusing on solar twins and planet hosting stars. I will discuss the observed large-scale magnetic cycles, compare them to stellar activity cycles, and link that to what we know about the Sun. I will also discuss the effect of large-scale stellar fields on exoplanets, exoplanetary emissions (e.g. radio), and habitability.

scholarly journals The modes of magnetic field generation in a low-mode model of αΩ-dynamo with α-generator varying intensity regulated by a function with an alternating kernel

2021 ◽  
Vol 254 ◽  
pp. 02015
Author(s):  
Olga V. Sheremetyeva ◽  
Anna N. Godomskaya
Keyword(s):  
Magnetic Field ◽  
Numerical Simulation ◽  
Large Scale ◽  
Damping Coefficient ◽  
Field Energy ◽  
Control Parameters ◽  
Magnetic Field Generation ◽  
Field Generation ◽  
Mhd System ◽  
The Magnetic Field

The low-mode model αΩ-dynamo is used in this paper to simulate the modes of magnetic field generation with insignificant changes in the velocity field of a viscous fluid. In the framework of those model the α-effect intensity is regulated by the process that is included in the magnetohydrodynamic system (MHD-system) as an additive correction as a functional Z(t) depended on the magnetic field energy. Function that determines damped oscillations with variable damping frequency and constant damping coefficient, taken equal to one, is selected as kernel J(t) of functional Z(t). The research of the behavior of the magnetic field is carried out on large time scales, therefore, a rescaled and dimensionless MHD-system with the unit of time iquel the time of the magnetic field dissipation (104 years) for numerical calculations is used. The control parameters of the system are the Reynolds number and the amplitude of the α-effect, that include information about the large-scale and turbulent generators, respectively. Numerical simulation of the magnetic field generation modes was carried out for the values of the damping coefficient b = 1 and frequency a = 0.1, 0.5, 1, 5, 10. According to the results of numerical simulation, an increase in the values of the damping frequency, when the damping coefficient is equal to one, is characterized by a decrease in the inhibitory effect of the process Z(t) on the α-effect and an increase in the region of divergence of the magnetic field on the phase plane of the control parameters. In a comparative analysis with the results of the authors’ work, where the change of the α-effect intensity was determined by the function Z(t) with an exponential kernel and the same value of the damping coefficient, the following differences were noted: an increase in oscillations in both a magnetic and a velocity fields, the appearance of a chaotic regime of magnetic field generation at the value of the damping frequency equal to one, and also insignificant narrowing of the region of α-effect suppression at values of the damping frequency increasing to one.

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