English
Related papers

Related papers: Benchmarking the solar dynamo with Maxima

200 papers

We discuss the potential use of an algebraic method to compute the value of the solar axial dipole moment at solar minimum, widely considered to be the most reliable precursor of the activity level in the next solar cycle. The method…

Solar and Stellar Astrophysics · Physics 2020-10-29 Kristóf Petrovay , Melinda Nagy , Anthony R. Yeates

The homogeneous dynamo effect is at the root of cosmic magnetic field generation. With only a very few exceptions, the numerical treatment of homogeneous dynamos is carried out in the framework of the differential equation approach. The…

Astrophysics · Physics 2009-11-10 Mingtian Xu , Frank Stefani , Gunter Gerbeth

In this article we review small-scale dynamo processes that are responsible for magnetic field generation on scales comparable to and smaller than the energy carrying scales of turbulence. We provide a review of critical observation of…

Solar and Stellar Astrophysics · Physics 2023-07-19 Matthias Rempel , Tanayveer Bhatia , Luis Bellot Rubio , Maarit J. Korpi-Lagg

Keeping in mind the current picture of an accelerating and flat Universe, some specific dynamical models of the cosmological term $\Lambda$ have been selected for investigating the nature of dark energy. Connecting the free parameters of…

Astrophysics · Physics 2008-11-26 Saibal Ray , Utpal Mukhopadhyay , Xin-He Meng

We assess the global-scale dynamo action achieved in a simulation of a sun-like star rotating at three times the solar rate. The 3-D MHD Anelastic Spherical Harmonic code, using slope-limited diffusion, is employed to capture convection and…

Solar and Stellar Astrophysics · Physics 2013-11-01 Kyle Augustson , Allan Sacha Brun , Mark Steven Miesch , Juri Toomre

Equilibrium dynamical models are essential tools for extracting science from surveys of our Galaxy. We show how models can be tested with data from a survey before the survey's selection function has been determined. We illustrate the…

Astrophysics of Galaxies · Physics 2015-06-17 James Binney , Jason L Sanders

The large-scale magnetic field observed at the solar surface is produced by the interior dynamo process. Whether this surface field also provides the dominant seed for the subsequent dynamo cycle, however, remains controversial, with…

Solar and Stellar Astrophysics · Physics 2026-04-16 Binghang Li , Jie Jiang , Yukun Luo

We study how the classical tests of general relativity are modified by the presence of a subdominant dark matter halo in the solar system. We use a general formalism to calculate the corrected expression for the relevant parameters, and…

General Relativity and Quantum Cosmology · Physics 2012-07-26 Giuseppe De Risi , Tiberiu Harko , Francisco S. N. Lobo

In this work we study the cosmological evolution of a two component model with non-relativistic dark matter and decaying vacuum of the form $\Lambda = \Lambda_0 + 3 \beta H^2.$ We contrast the model the model with the supernovae data and…

General Relativity and Quantum Cosmology · Physics 2018-10-23 Jayadevan A P , Mukesh M , Shaima Akbar , Titus K Mathew

While obviously having a common root, solar and planetary dynamo theory have taken increasingly divergent routes in the last two or three decades, and there are probably few experts now who can claim to be equally versed in both.…

Solar and Stellar Astrophysics · Physics 2014-11-18 K. Petrovay

In order better to understand how dynamo systems saturate, we study the kinematic dynamo properties of velocity fields that arise from nonlinearly saturated dynamos. The technique is implemented by solving concurrently, in addition to the…

Fluid Dynamics · Physics 2008-09-13 Fausto Cattaneo , Steve M. Tobias

In the first part of this report we present the results of a model independent analysis of the existing solar neutrino data. We obtained forbidden regions in the plane of the parameters Delta m^2 and sin^2 2 theta in two cases: A) Without…

High Energy Physics - Phenomenology · Physics 2008-02-03 S. M. Bilenky , C. Giunti

Based on mathematical model of the statistical Fermi system with the interparticle interaction which was constructed in the previous articles, this work offers the construction and analysis of the numerical models of cosmological evolution…

General Relativity and Quantum Cosmology · Physics 2023-07-19 Yu. G. Ignatyev , A. A. Agathonov

A brief summary of the various observations and constraints that underlie solar dynamo research are presented. The arguments that indicate that the solar dynamo is an alpha-omega dynamo of the Babcock-Leighton type are then shortly…

Solar and Stellar Astrophysics · Physics 2017-09-26 R. H. Cameron , M. Dikpati , A. Brandenburg

Solar magnetic activity shows both smooth secular changes, such as the Grand Modern Maximum, and quite abrupt drops that are denoted as Grand Minima. Direct numerical simulations (DNS) of convection driven dynamos offer one way of examining…

Solar and Stellar Astrophysics · Physics 2016-04-13 Maarit J. Käpylä , Petri J. Käpylä , Nigul Olspert , Axel Brandenburg , Jörn Warnecke , Bidya B. Karak , Jaan Pelt

Running Dark Energy and Dark Matter models are candidates to resolve the Hubble constant tension. However the model does not consider a Lagrangian formulation directly. In this paper we formulate an action principle where the Running Vacuum…

General Relativity and Quantum Cosmology · Physics 2021-04-26 Shreya Banerjee , David Benisty , Eduardo I. Guendelman

In a recent paper Dar and Shaviv (1994) presented results of calculations with an improved standard solar model (SSM) that suggest a standard physics solution to the solar neutrino problem. In a subsequent publication with a similar title…

Astrophysics · Physics 2007-05-23 Arnon Dar , Giora Shaviv

We update the capabilities of the open-knowledge software instrument Modules for Experiments in Stellar Astrophysics (MESA). The new auto_diff module implements automatic differentiation in MESA, an enabling capability that alleviates the…

We present a model problem for benchmarking codes that investigate magma migration in the Earth's interior. This system retains the essential features of more sophisticated models, yet has the advantage of possessing solitary wave…

Geophysics · Physics 2010-09-03 Gideon Simpson , Marc Spiegelman

The neutrino long wavelength (just-so) oscillation is revisited as a solution to the solar neutrino problem. We consider just-so scenario in various cases: in the framework of the solar models with relaxed prediction of the boron neutrino…

High Energy Physics - Phenomenology · Physics 2008-11-26 Z. Berezhiani , A. Rossi