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We present our results concerning a systematical analysis of helioseismic implications on solar structure and neutrino production. We find Y$_{ph}=0.238-0.259$, $R_b/R_\odot=0.708-0.714$ and $\rho_b=(0.185-0.199)$ gr/cm$^3$. In the interval…

Astrophysics · Physics 2015-06-24 V. Castellani , S. Degl'Innocenti , W. A. Dziembowski , G. Fiorentini , B. Ricci

The latitudinal sound-speed structure of the Sun's convection zone gives insight into the physical processes occurring there, specifically the cellular convection and possibly the presence of magnetic fields. Using helioseismic data from…

Astrophysics · Physics 2008-11-26 H. M. Antia , S. M. Chitre , M. J. Thompson

Inversions to determine the squared isothermal sound speed and density within the Sun often use the helium abundance Y as the second parameter. This requires the explicit use of the equation of state (EOS), thus potentially leading to…

Astrophysics · Physics 2007-05-23 Sarbani Basu , J. Christensen-Dalsgaard

Inferring interior properties of the Sun from photospheric measurements of the seismic wavefield constitutes the helioseismic inverse problem. Deviations in seismic measurements (such as wave travel times) from their fiducial values…

Solar and Stellar Astrophysics · Physics 2015-06-18 Shravan Hanasoge , Jeroen Tromp

We present a new method for helioseismic diagnostics of the three-dimensional structure of sound speed, magnetic fields and flow velocities in the convection zone by inversion of acoustic travel-time data. The data are measurements of the…

Solar and Stellar Astrophysics · Physics 2018-06-11 A. G. Kosovichev , T. L. Duvall

We examine the constraints imposed by helioseismic data on the solar heavy element abundances. In prior work we argued that the measured depth of the surface convection zone R_CZ and the surface helium abundance Y_surf were good metallicity…

Solar and Stellar Astrophysics · Physics 2010-05-05 F. Delahaye , M. H. Pinsonneault , L. Pinsonneault , C. J. Zeippen

Helioseismology has provided very detailed information about the solar interior, and extensive data on a large number of stars, although at less detail, are promised by the ongoing and upcoming asteroseismic projects. In the solar case…

Solar and Stellar Astrophysics · Physics 2015-05-19 J. Christensen-Dalsgaard

The solar interior has been scrutinized by two different and independent probes during the last twenty years with important revisions of the solar model, including a recent heavy element abundance revision. Today, we get a quantitatively…

Astrophysics · Physics 2009-11-11 S. Turck-Chieze , S. Couvidat , L. Piau

Since the first observations of solar oscillations, helioseismology has been one of the most successful fields of astrophysics. Data of high quality were obtained through the implementation of networks of ground-based observatories such as…

Solar and Stellar Astrophysics · Physics 2019-06-20 G. Buldgen , A. Noels , S. Salmon

The structure of the surface layers of the Sun is changed by magnetic activity which, in turn, changes the eigenfrequencies of the acoustic modes. These frequency shifts have been observed both in low- and high-degree data, and are found to…

Astrophysics · Physics 2007-05-23 M. Cunha , M. Bruggen , D. O. Gough

In previous work, we have shown that recent updated standard solar models cannot reproduce the radial profile of the sound speed at the base of the convective zone (CZ) and fail to predict the Li7 depletion. In parallel, helioseismology has…

Astrophysics · Physics 2010-04-06 A. S. Brun , S. Turck-Chieze , J. P. Zahn

Context. Acoustic waves in the Sun are affected by the atmospheric layers, but this region is often ignored in forward models due to the increase in computational cost. Aims. The purpose of this work is to take into account the solar…

Solar and Stellar Astrophysics · Physics 2025-07-15 Damien Fournier , Janosch Preuss , Thorsten Hohage , Laurent Gizon

The frequencies of solar oscillations are known to change with solar activity. We use Principal Component Analysis to examine these changes with high precision. In addition to the well-documented changes in solar normal mode oscillations…

Astrophysics · Physics 2009-11-13 Charles S. Baldner , Sarbani Basu

The faint young Sun paradox remains an open question. Presented here is one possible solution to this apparent inconsistency, a more massive early Sun. Based on conditions on early Earth and Mars, a luminosity constraint is set as a…

Solar and Stellar Astrophysics · Physics 2018-08-08 Suzannah R. Wood , Katie Mussack , Joyce A. Guzik

Solar models through evolutionary phases of gravitational contraction, pre-main sequence and MS phases, up to current age 4.5E9 yr. and 4.57E9 yr., were studied adopting different prescriptions for the equation of state (EOS) and different…

Astrophysics · Physics 2007-05-23 M. Yildiz , N. Kiziloglu

There have been recent downward revisions of the solar photospheric abundances of Oxygen and other heavy elements. These revised abundances along with OPAL opacities are not consistent with seismic constraints. In this work we show that the…

Astrophysics · Physics 2011-08-03 H. M. Antia , Sarbani Basu

Important revisions of the solar model ingredients appear after 35 years of intense work which have led to an excellent agreement between solar models and solar neutrino detections. We first show that the updated CNO composition suppresses…

With the recent results of helioseismology aboard SOHO, solar models are more and more constrained (Brun, Turck-Chieze and Morel 1998 (astro-ph/9806272)). New physical processes, mainly connected to macroscopic motions, must be introduced…

Astrophysics · Physics 2007-05-23 A. S. Brun , S. Turck-Chieze , J. P. Zahn

Oscillations detected on the solar surface provide a unique possibility for investigations of the interior properties of a star. Through major observational efforts, including extensive observations from space, as well as development of…

Astrophysics · Physics 2008-11-26 J. Christensen-Dalsgaard

Local mixing-length theory is incapable of describing nonlocal phenomena in stellar convection, such as overshooting. Therefore standard solar models constructed with the local mixing-length theory deviate significantly from the Sun at the…

Solar and Stellar Astrophysics · Physics 2015-06-15 Chunguang Zhang , Licai Deng , Darun Xiong , Jørgen Christensen-Dalsgaard
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