Interactions among convection, magnetic fields and P-mode oscillations in the sun

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National Aeronautics and Space Administration, National Technical Information Service, distributor , [Washington, DC, Springfield, Va
Convection (Astrophysics), Magnetic fi
StatementPeter Goldreich, principal investigator.
Series[NASA contractor report] -- NASA CR-194477., NASA contractor report -- NASA CR-194477.
ContributionsUnited States. National Aeronautics and Space Administration.
The Physical Object
Pagination1 v.
ID Numbers
Open LibraryOL14701056M

Get this from a library. Interactions among convection, magnetic fields and P-mode oscillations in the sun. [Peter Goldreich; United States. National Aeronautics and Space Administration.]. INTERACTIONS AMONG CONVECTION, MAGNETIC FIELDS AND P-MODE OSCILLATIONS IN THE SUN Peter Goldreich, Principal Investigator Division of Geological and Planetary Sciences California Institute of Technology Pasadena, California / To cover the period 1/1/93 through 12/31/93 (NASA-CRY) INTERACTIONS AMONG CONVECTION, MAGNETIC FIELDS.

Interactions among convection, magnetic fields and p-mode oscillations in the sun. By Peter Goldreich. Abstract. Two Interactions among convection on different aspects of the excitation and damping of solar oscillations were accepted for publication in the Astrophysical Journal.

The first paper evaluates the rate at which turbulent convection feeds energy into Author: Peter Goldreich. Vigorous convection produces local flux concentrations with magnetic fields that may be much greater than the equipartition value.

The interaction between magnetic fields and convection can be observed in detail on the sun and is essential to any stellar by:   System Upgrade on Fri, Jun 26th, at 5pm (ET) During this period, our website will be offline for less than an hour but the E-commerce and registration of new.

The oscillations for the Interactions among convection edge of Cepheid (δ Scuti) instability strip, Sun-like and Mira-like stars can be explained uniformly by the coupling between convection and oscillation (CCO).

We present a formalism for investigating the interaction between pmode oscillations and convection by analyzing realistic, three-dimensional simulations of the.

The interaction between magnetic fields and convection can be observed in detail on the sun and is essential to any stellar dynamo. In a highly conducting plasma. show magnetic flux emerging in ephemeral active regions to form the so-called magnetic carpet and being swept into the supergranular network, while G-band images from La Palma reveal rapidly evolving fine-scale fields in intergranu-lar lanes.

Thus, it becomes important to model the local interactions between convection and magnetic fields.

Download Interactions among convection, magnetic fields and P-mode oscillations in the sun FB2

Nonlinear two-dimensional magnetoconvection in a Boussinesq fluid has been studied in a series of numerical experiments with values of the Chandrasekhar number Q ≤ and the ratio ζ of the magnetic to the thermal diffusivity in the range 1 ≥ ζ ≥ 0 If the imposed field is strong enough, convection sets in as overstable oscillations which give way to steady convection as the.

One of the possible magnetic field effects on the stellar pulsations is known to be a splitting in the observed frequencies. Using this knowledge in the solar convection zone, there are two aims in this work Considering the Sun as an incompressible fluid, our first objective was to investigate the variation of the physical parameters in the 30% outermost convective solar layer, during a.

Starting from a stationary solution under a northward interplanetary magnetic field (IMF) condition with non-zero IMF B y, changes in magnetospheric convection following the southward turning of the IMF are investigated.

The simulation results first show the progress of plasma sheet thinning in the tail. The interaction between the sun and Earth’s magnetic fields sometimes cause storms of explosive nature in the space near Earth. Understanding these interactions is important to help protect and improve the performance of satellites.

NASA’s Magnetospheric Multiscale (MMS) mission’s results have provided the first direct and detailed observation of magnetic reconnection. Spiegel and Weiss 1 have recently discussed how magnetic fields can intrude into this envelope to affect convection and thus introduce transients into the Sun's luminosity.

I demonstrate here from. The interaction between magnetic fields and convection can be observed directly in the Sun. Where the field is strong, as in sunspots, normal convection is inhibited. Where the average field strength is less, magnetic flux is concentrated into isolated tubes or ropes, and such intermittent structures seem to be characteristic of turbulent.

The Sun among the Stars. Cornelis Zwaan. Pages Techniques. Front Matter. Dynamic Interaction of Convection with Magnetic Flux Sheets: First Results of a New MHD Code.

Steiner, M. Knölker, M. Schüssler Observations of the solar magnetic field are largely confined to the radiation emitted from the photosphere, the thin layer of. This chapter is concerned primarily with some aspects of the interaction between turbulent convection and a magnetic field in the Sun, and so also in other late.

This thesis describes the studies on the solar interior where turbulent thermal convection plays an important role. The author solved, for the first time, one of the long-standing issues in solar physics, i.e., the maintenance mechanism of the solar differential rotation in the near-surface shear.

Interaction of Magnetic Fields (Motor Action) Currents in the same direction Flux in space between conductors in “opposite” directions Force of attraction acts to pull the conductors together Elementary Two-Pole Motor Rotor core with 2 insulated conductors in “slots” A stationary magnet – the “stator” Current-Carrying Conductor in.

In this section, we explore the interaction of steady magnetic fields with convection. In particular, we look at the possibility of steady fields in the radiative interiors of solar-type stars, shielded from becoming observable at the surface (§) and how these might interact with the convective envelope above (§).

The present study is devoted to the problem of onset of oscillatory instability in convective flow of an electrically conducting fluid under an externally imposed time-independent uniform magnetic field.

Convection of a low-Prandtl-number fluid in a laterally heated two-dimensional horizontal cavity is considered. Fixed values of the aspect ratio (length/height=4) and Prandtl number (Pr= Recent 3-D work has looked at the interaction of magnetic fields and mesoscale granular flows.

In one study a vertical magnetic field is allowed to be swept into a downdraft; the results are similar to the 2-D case. More interestingly, other simulations follow the fate of a horizontal flux distribution released at the base of the convection zone. @article{osti_, title = {Interaction of convection and small-scale magnetic fields: influence on the solar luminosity}, author = {Nordlund, A.}, abstractNote = {Changes in the local solar luminosity due to the presence of a small scale structured (facular) magnetic field in the photosphere are discussed.

The discussion is based on three dimensional numerical simulations of the. The directional effect of a magnetic field on the onset of oscillatory convection is studied numerically in a confined three-dimensional cavity of relative dimensions (length:width:height) filled with mercury and subject to a horizontal temperature gradient.

The magnetic field suppresses the oscillations most effectively when it is applied in the vertical direction, and is the least. r is the radial magnetic flux, uis the horizontal velocity vector (which includes the observed axisymmetric flows and the convective flows), and S is a (magnetic) source term as a function of latitude, longitude, and time.

This purely advective model is supported by both theory and observation. The Sun’s magnetic field elements are carried. magnetic activity on the sun b.

electrical activity on the sun c. the interaction of the Sun's magnetic field and the interstellar medium d.

Details Interactions among convection, magnetic fields and P-mode oscillations in the sun PDF

the interaction of the solar wind and Earth's magnetic field e. the interaction of the solar wind and the Sun's magnetic field.

Give an everyday example of hydrostatic equilibrium not presented in the book. lightly colored convection features about km in diameter seen constantly in the solar photosphere.

a year cycle during which the Sun's magnetic field reverses its polarity twice. solar flare.

Description Interactions among convection, magnetic fields and P-mode oscillations in the sun EPUB

a violent eruption on the Sun's surface. Convectively Driven Sinks and Magnetic Fields in the Quiet-Sun Iker S. Requerey1,2,3, Jose Carlos Del Toro Iniesta1, Luis R. Bellot Rubio1, Valentín Martínez Pillet4, Sami K. Solanki5,6, and Wolfgang Schmidt7 1 Instituto de Astrofísica de Andalucía (CSIC), Apdo.

de CorreosE Granada, Spain; [email protected] 2 Instituto de Astrofísica de Canarias, Vía Láctea s/n, E La Laguna. Magnetic Interactions with Moving Charge This is an active graphic. Click on any part for further details. p-mode line profiles.

The interaction between the oscillations, convection and radiation is also responsible for the asymmetry of the mode’s spectra and the reversal of asymmetry between velocity and intensity.

There is disagreement as to which is the dominant mechanism producing the asymmetry and its reversal. The Scientific Committee on Solar–Terrestrial Physics (SCOSTEP) of the International Council for Science (ICSU) implemented an international collaborative program called Climate and Weather of the Sun–Earth System (CAWSES), which was active from to ; this was followed by the CAWSES II program during the period of – The CAWSES program was aimed at .Magnetic fields from convection?

In the Sun, the flows of hot plasma in the convection zone create the solar magnetic field. The plasma is a hot gas "soup" with many free charged particles (electrons and protons). The moving charges are a current, and produce magnetic fields, just like the current in coils of wire around the nail.This chapter generalizes the mixing-length description of stellar convection to include steady non-uniform rotation.

Both the effect of convective motions on an imposed weak magnetic field, and the effect of a strong field on the criteria for the onset of convection, lead to the study of fully non-linear magnetoconvection. The sunspot phenomenon is traced to the interference of an essentially.