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Related papers: On Solar Radius Variation with Magnetic Field

200 papers

The Solar Cycle is reviewed. The 11-year cycle of solar activity is characterized by the rise and fall in the numbers and surface area of sunspots. A number of other solar activity indicators also vary in association with the sunspots…

Solar and Stellar Astrophysics · Physics 2015-10-01 David H. Hathaway

When our Sun was young it rotated much more rapidly than now. Observations of young, rapidly rotating stars indicate that many possess substantial magnetic activity and strong axisymmetric magnetic fields. We conduct simulations of dynamo…

Solar and Stellar Astrophysics · Physics 2009-06-15 Benjamin P. Brown , Matthew K. Browning , Mark S. Miesch , Allan Sacha Brun , Juri Toomre

Torsional oscillations represent bands of fast and slow zonal flows around the Sun, which extend deep into the convection zone and migrate during solar cycles towards the equator following the sunspot butterfly diagram. Analysis of…

Solar and Stellar Astrophysics · Physics 2019-01-15 Alexander G. Kosovichev , Valery V. Pipin

Magnetic activity is a ubiquitous feature of stars with convective outer layers, with implications from stellar evolution to planetary atmospheres. Investigating the mechanisms responsible for the observed stellar activity signals from days…

Solar and Stellar Astrophysics · Physics 2023-10-17 Emre Işık , Jennifer L. van Saders , Ansgar Reiners , Travis S. Metcalfe

We explore the cause of the solar cycle variabilities using a novel 3D Babcock--Leighton dynamo model. In this model, based on the toroidal flux at the base of the convection zone, bipolar magnetic regions (BMRs) are produced with…

Solar and Stellar Astrophysics · Physics 2019-01-30 Bidya Binay Karak , Mark Miesch

In 1969 Leighton developed a quasi-1D mathematical model of the solar dynamo, building upon the phenomenological scenario of Babcock(1961). Here we present a modification and extension of Leighton's model. Using the axisymmetric component…

Solar and Stellar Astrophysics · Physics 2017-03-01 R. H. Cameron , M. Schuessler

Simple models of magnetic field generation by convection in rotating spherical shells exhibit properties resembling those observed on the sun. The {assumption of the Boussinesq approximation made in these models} prevents a realistic…

Solar and Stellar Astrophysics · Physics 2015-06-03 Radostin D. Simitev , Friedrich H. Busse

The transition from liquid metal to silicate rock in the cores of the terrestrial planets is likely to be accompanied by a gradient in the composition of the outer core liquid. The electrical conductivity of a volatile enriched liquid alloy…

Earth and Planetary Astrophysics · Physics 2010-03-23 Natalia Gomez-Perez , Moritz H. Heimpel , Johannes Wicht

A model for the solar dynamo, consistent in global flow and numerical method employed with the differential rotation model, is developed. The magnetic turbulent diffusivity is expressed in terms of the entropy gradient, which is controlled…

Solar and Stellar Astrophysics · Physics 2017-06-28 L. L. Kitchatinov , A. A. Nepomnyashchikh

The magnetic fields of low-mass stars are observed to be variable on decadal timescales, ranging in behaviour from cyclic to stochastic. The changing strength and geometry of the magnetic field should modify the efficiency of angular…

Solar and Stellar Astrophysics · Physics 2019-05-08 Adam J. Finley , Victor See , Sean P. Matt

The surprising thinness of the solar tachocline is still not understood with certainty today. Among the numerous possible scenarios suggested to explain its radial confinement, one hypothesis is based on Maxwell stresses that are exerted by…

Solar and Stellar Astrophysics · Physics 2017-04-26 R. Barnabé , A. Strugarek , P. Charbonneau , A. S. Brun , J. -P. Zahn

The dynamics of the solar radiative interior are still poorly constrained by comparison to the convective zone. This disparity is even more marked when we attempt to derive meaningful temporal variations. Many data sets contain a small…

Solar and Stellar Astrophysics · Physics 2015-06-05 Antonio Eff-Darwich , Sylain G. Korzennik

Apart from the 11-year solar cycle, another periodicity around 155-160 days was discovered during solar cycle 21 in high energy solar flares, and its presence in sunspot areas and strong magnetic flux has been also reported. This…

Solar and Stellar Astrophysics · Physics 2014-11-20 T. V. Zaqarashvili , M. Carbonell , R. Oliver , J. L. Ballster

Using different proxies of solar activity, we have studied the following features of solar cycle. (i) A linear correlation between the amplitude of cycle and its decay rate, (ii) a linear correlation between the amplitude of cycle $n$ and…

Solar and Stellar Astrophysics · Physics 2015-08-06 Gopal Hazra , Bidya Binay Karak , Dipankar Banerjee , Arnab Rai Choudhuri

The Sun, aside from its eleven year sunspot cycle is additionally subject to long term variation in its activity. In this work we analyse a solar-like convective dynamo simulation, containing approximately 60 magnetic cycles, exhibiting…

Solar and Stellar Astrophysics · Physics 2017-10-11 Frederick A. Gent , Maarit J. Käpylä , Jörn Warnecke

The recent burst in the number of radii measurements of very low-mass stars from eclipsing binaries and interferometry of single stars has opened more questions about what can be causing the discrepancy between the observed radii and the…

Astrophysics · Physics 2011-02-11 Mercedes Lopez-Morales

Sixteen years of meteor radar data from the Canadian Meteor Orbit Radar (CMOR) were used to investigate the link between observed meteor rates and both solar and geomagnetic activity. Meteor rates were corrected for transmitter power and…

Earth and Planetary Astrophysics · Physics 2019-03-20 Margaret D. Campbell-Brown

In addition to sunspots, which represent the most easily visualized manifestation of solar magnetism, cutting-edge observations of the solar atmosphere have uncovered a plethora of magnetic flux tubes, down to the resolving power of modern…

Solar and Stellar Astrophysics · Physics 2025-02-27 M. Stangalini , G. Verth , V. Fedun , D. Perrone , M. Berretti , P. Bushby , S. Jafarzadeh , D. B. Jess , F. Giannattasio , P. H. Keys , R. Bruno , F. Berrilli

Understanding the reasons of the cyclic variation of the total solar irradiance is one of the most challenging targets of modern astrophysics. These studies prove to be essential also for a more climatologic issue, associated to the global…

Solar and Stellar Astrophysics · Physics 2011-03-28 P. Ventura , V. Penza , L. Li , S. Sofia , S. Basu , P. Demarque

The importance of the quiet-Sun magnetism is that it is always there to a greater or lesser extent, being a constant provider of energy, independently of the solar cycle phase. The open questions about the quiet-Sun magnetism include those…

Solar and Stellar Astrophysics · Physics 2023-02-16 Juan Carlos Trelles Arjona , María Jesús Martínez González , Basilio Ruiz Cobo