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Related papers: Inversions for Deep Solar Meridional Flow Using Sp…

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We derive expectations for signatures in the measured travel times of waves that interact with thermal anomalies and jets. A series of numerical experiments that involve the dynamic linear evolution of an acoustic wave field in a solar-like…

Astrophysics · Physics 2011-02-11 Shravan M. Hanasoge , Thomas L. Duvall

Temporal variations of the subsurface meridional flow with the solar cycle have been reported by several authors. The measurements are typically averaged over periods of time during which surface magnetic activity existed in the regions…

Astrophysics · Physics 2008-09-05 I. Gonzalez Hernandez , S. Kholikov , F. Hill , R. Howe , R. Komm

We measure the axisymmetric transport of magnetic flux on the Sun by cross-correlating narrow strips of data from line-of-sight magnetograms obtained at a 96-minute cadence by the MDI instrument on the ESA/NASA SOHO spacecraft and then…

Solar and Stellar Astrophysics · Physics 2011-03-30 David H. Hathaway , Lisa Rightmire

The radial gradient of the rotation rate in the near-surface shear layer (NSSL) of the Sun is independent of latitude and radius. Theoretical mean-field models have been successful in explaining this property of the solar NSSL, while global…

Solar and Stellar Astrophysics · Physics 2021-12-01 A. Barekat , M. J. Käpylä , P. J. Käpylä , E. P. Gilson , H. Ji

We report the first observation of protons in the near (100--200 km from surface) and deeper (near anti-subsolar point) lunar plasma wake when the interplanetary magnetic field (IMF) and solar wind velocity ($v_{sw}$) are parallel (aligned…

The main object of the paper is to present the condition of the non-diffusive part of the Reynolds stress for driving the double-cell structure of the solar meridional circulation, which has been revealed by recent helioseismic…

Solar and Stellar Astrophysics · Physics 2017-01-25 Yuto Bekki , Takaaki Yokoyama

Multiwavelength observations of the propagating disturbances (PDs), discovered by Atmospheric Imaging Assembly (AIA) onboard Solar Dynamics Observatory (SDO), are analyzed to determine its driving mechanism and physical nature. Two magnetic…

Measuring the Sun's internal meridional flow is one of the key issues of helioseismology. Using the Fourier-Legendre analysis is a technique for addressing this problem. We validate this technique with the help of artificial helioseismic…

Solar and Stellar Astrophysics · Physics 2016-08-10 Markus Roth , Hans-Peter Doerr , Thomas Hartlep

Transport by meridional flows has significant consequences for stellar evolution, but is difficult to capture in global-scale numerical simulations because of the wide range of timescales involved. Stellar evolution models therefore usually…

Solar and Stellar Astrophysics · Physics 2015-01-22 Toby S. Wood , Nicholas H. Brummell

Helioseismology shows that the regions occupied by convection and differential rotation inside the sun almost coincide. This supports the leading theoretical concept for the origin of differential rotation as a result of interaction between…

Solar and Stellar Astrophysics · Physics 2011-10-12 L. L. Kitchatinov

Since the CoRoT and Kepler missions, the availability of high quality seismic spectra for red giants has made them the standard clocks and rulers for Galactic Archeology. With the expected excellent data from the TESS and PLATO missions,…

Solar and Stellar Astrophysics · Physics 2018-09-05 Gaël Buldgen , B. Rendle , T. Sonoi , G. R. Davies , A. Miglio , S. J. A. J. Salmon , D. R. Reese , D. Bossini , P. Eggenberger , A. Noels , R. Scuflaire

We constrain the velocity spectral distribution of global-scale solar convective cells at depth using techniques of local helioseismology. We calibrate the sensitivity of helioseismic waves to large-scale convective cells in the interior by…

Solar and Stellar Astrophysics · Physics 2015-05-18 S. M. Hanasoge , T. L. Duvall , M. L. DeRosa

The Sun is a magnetic star whose magnetism and cyclic activity is linked to the existence of an internal dynamo. We aim to understand the establishment of the solar magnetic 22-yr cycle, its associated butterfly diagram and field parity…

Astrophysics · Physics 2008-11-26 L. Jouve , A. S. Brun

Observations of the meridional circulation of the Sun, which plays a key role in the operation of the solar dynamo, indicate that its speed varies with the solar cycle, becoming faster during the solar minima and slower during the solar…

Solar and Stellar Astrophysics · Physics 2017-10-11 Gopal Hazra , Arnab Rai Choudhuri

Downflows on the solar surface are suspected to play a major role in the dynamics of the convection zone. We investigate the existence of the long-lasting downflows whose effects influence the interior of the Sun and the outer layers. We…

Solar and Stellar Astrophysics · Physics 2021-03-05 T. Roudier , M. Švanda , J. M. Malherbe , J. Ballot , D. Korda , Z. Frank

We present a quantitative estimate of the accuracy of the calculated diffusion coefficients, by comparing predictions of solar models with observational data provided by helioseismology. By taking into account the major uncertainties in…

Astrophysics · Physics 2011-01-04 G. Fiorentini , M. Lissia , B. Ricci

(abridged) Results from kinematic solar dynamo models employing alpha-effect and turbulent pumping from local convection calculations are presented. We estimate the magnitude of these effects to be around 2-3 m/s. The rotation profile of…

Astrophysics · Physics 2008-11-26 P. J. Käpylä , M. J. Korpi , I. Tuominen

In its first encounter at solar distances as close as r = 0.16AU, Parker Solar Probe (PSP) observed numerous local reversals, or inversions, in the heliospheric magnetic field (HMF), which were accompanied by large spikes in solar wind…

Solar and Stellar Astrophysics · Physics 2021-01-06 Allan R Macneil , Mathew J Owens , Robert T Wicks , Mike Lockwood

Measurements of the large cellular flows on the Sun were made by local correlation tracking of supergranules seen in full-disk Doppler images obtained by the HMI instrument on the NASA SDO satellite. The hourly measurements were averaged…

Solar and Stellar Astrophysics · Physics 2021-02-24 David H. Hathaway , Lisa A. Upton

Standard solar models (SSMs) constructed in accordance with old solar abundances are in reasonable agreement with seismically inferred results, but SSMs with new low-metal abundances disagree with the seismically inferred results. The…

Solar and Stellar Astrophysics · Physics 2022-11-09 Wuming Yang