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A linear quantum harmonic oscillator factors into one dimensional oscillators and can be solved using creation and annihilation operators. We consider a spherical analogue. This analogue does not factor. The two dimensional case is…

Mathematical Physics · Physics 2025-10-21 Van Higgs , Doug Pickrell

We investigated the $\alpha$ and $\beta$ effects in a rotating spherical plasma system relevant to astrophysical environments. These coefficients were derived using three different approaches based on the large-scale magnetic field…

Plasma Physics · Physics 2025-08-04 Kiwan Park

We present a new scenario for magnetic field amplification where an electrically conducting fluid is confined in a differentially rotating, spherical shell with thin aspect-ratio. When the angular momentum sufficiently decreases outwards,…

Fluid Dynamics · Physics 2016-06-14 Florence Marcotte , Christophe Gissinger

The duration of activity growths in solar cycles is on average shorter than the duration of its declines. This asymmetry can result from fluctuations in dynamo parameters. A solar dynamo model with fluctuations in the $\alpha$-effect shows…

Solar and Stellar Astrophysics · Physics 2018-11-07 Leonid Kitchatinov , Alexander Nepomnyashchikh

The nonlocal alpha-effect of Babcock-Leighton type is not prone to the catastrophic quenching due to conservation of magnetic helicity. This is shown with a dynamo model, which jointly applies the nonlocal alpha-effect, the diamagnetic…

Solar and Stellar Astrophysics · Physics 2015-05-27 L. L. Kitchatinov , S. V. Olemskoy

This paper investigates dynamics of axial reflection symmetric model in self-interacting Brans-Dicke gravity for anisotropic fluid. We formulate hydrodynamical equations and discuss oscillations using time-dependent perturbation for both…

General Relativity and Quantum Cosmology · Physics 2016-07-22 M. Sharif , Rubab Manzoor

We analyze the obtained solutions of the non-linear Shroedinger equation for spherically and axially symmetrical electrons density oscillations in plasma. The conditions of the oscillations process existence are examined. It is shown that…

Plasma Physics · Physics 2009-07-31 Maxim Dvornikov , Sergey Dvornikov

Many stars exhibit strong magnetic fields, some of which are thought to be of primordial origin and others a sign of magnetic dynamo processes. We briefly review the results of observational studies of solar-type stars seeking to evaluate…

Astrophysics · Physics 2007-05-23 Allan Sacha Brun

In this work a classical linear harmonic oscillator, evolving during a small time interval (so that simple non-linear, second order Taylor approximation of the dynamics is satisfied) and restarting (by a mechanism) in a strictly chosen…

Quantum Physics · Physics 2009-08-18 Vladan Panković

This work tackles a significant challenge in dynamo theory: the possibility of long-term amplification and maintenance of an axisymmetric magnetic field. We introduce a novel model that allows for non-trivial axially-symmetric steady-state…

Earth and Planetary Astrophysics · Physics 2025-07-08 Naoki Sato , Kumiko Hori

We present an axisymmetric numerical model of a dynamo active accretion disc. If the dynamo-generated magnetic field in the disc is sufficiently strong (close to equipartition with thermal energy), a fast magneto-centrifugally driven…

Astrophysics · Physics 2009-10-31 Brigitta von Rekowski , Axel Brandenburg , Wolfgang Dobler , Anvar Shukurov

The exploration of mean-field galactic dynamos affected by a galactic spiral pattern, begun in Chamandy et al. (2013, hereafter Paper I) with numerical simulations, is continued here with an asymptotic solution. The mean-field dynamo model…

Astrophysics of Galaxies · Physics 2015-06-12 Luke Chamandy , Kandaswamy Subramanian , Anvar Shukurov

We study the oscillations and stability of self-gravitating cylindrically symmetric fluid systems and collisionless systems. This is done by studying small perturbations to the equilibrium system and finding the normal modes, using methods…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-15 Patrick C. Breysse , Marc Kamionkowski , Andrew Benson

We show that simple 2 and 3-layer flux-transport dynamos, when forced at the top by a poloidal source term, can produce a widely varying amplitude of toroidal field at the bottom, depending on how close the meridional flow speed of the…

Solar and Stellar Astrophysics · Physics 2015-05-28 Peter A. Gilman , Mausumi Dikpati

Employing the standard solar interior model as input we construct a dynamically-consistent nonlinear dynamo model that takes into account the detailed description of the \Lambda- effect, turbulent pumping, magnetic helicity balance, and…

Solar and Stellar Astrophysics · Physics 2018-07-31 V. V. Pipin

We study the Dynamical Casimir Effect resulting from the oscillatory motion of either one or two flat semitransparent mirrors, coupled to a quantum real and massless scalar field. Our approach is based on a perturbative evaluation, in the…

High Energy Physics - Theory · Physics 2017-09-13 C. D. Fosco , A. Giraldo , F. D. Mazzitelli

The emergence of a large scale magnetic field from randomly forced isotropic strongly helical flows is discussed in terms of the inverse cascade of magnetic helicity and the alpha-effect. In simulations of such flows the maximum field…

Astrophysics · Physics 2007-05-23 Axel Brandenburg

Consider the Dirichlet-type space on the bidisk consisting of holomorphic functions $f(z_1,z_2):=\sum_{k,l\geq 0}a_{kl}z_1^kz_2^l$ such that $\sum_{k,l\geq 0}(k+1)^{\alpha_1} (l+1)^{\alpha_2}|a_{kl}|^2 <\infty.$ Here the parameters…

Complex Variables · Mathematics 2015-12-16 Greg Knese , Lukasz Kosinski , Thomas J. Ransford , Alan Sola

We explain the (non)helical dynamo process using a field-structure model based on magnetic induction equation in an intuitive way. We show how nonhelical kinetic energy converts into magnetic energy and cascades toward smaller eddies in a…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-27 Kiwan Park

We study large-scale kinematic dynamo action of steady mirror-antisymmetric flows of incompressible fluid, that involve small spatial scales only, by asymptotic methods of the multiscale stability theory. It turns out that, due to the…

Fluid Dynamics · Physics 2019-08-13 Alexander Andrievsky , Roman Chertovskih , Vladislav Zheligovsky
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