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Turck‐Chièze, S.; Nghiem, P.; Couvidat, S.; Turcotte, Sylvain

doi:10.1023/a:1010365125791

Cited by 41 publications

(40 citation statements)

References 17 publications

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“…It is the first time that we have been able to use an astrophysical object as a laboratory to determine a measure of an inaccessible yet fundamental nuclear reaction rate to an accuracy superior to that inferred from terrestrial experiment. Turck-Chièze et al (2001a) have shown the low sensitivity of the sound speed to CNO reaction rates, but Figure 2b shows that a more reliable seismic inference of the density may place significant constraints on screening or any dynamical effects of these reaction rates.…”

Section: Emitted Neutrino Fluxes and Discussionmentioning

confidence: 99%

“…Seismic analysis has been able to eliminate some proposals for the solution to the neutrino problem, such as central mixing or weakly interactive massive particles (e.g., Elsworth et al 1990;Christensen-Dalsgaard 1992;Turck-Chièze et al 1993, 2001a, although there remain others, such as asymmetric macroscopic motion in the core (Gough 1999), which may alter the predictions of the neutrino fluxes. In addition, through helioseismic inversion it is possible to construct seismic models consistent with the oscillation data and hence to predict the neutrino flux (e.g., Gough & Kosovichev 1990;Roxburgh 1996;Antia & Chitre 1997;Takata & Shibahashi 1998).…”

Section: Introductionmentioning

confidence: 99%

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Solar Neutrino Emission Deduced from a Seismic Model

Turck‐Chièze¹,

Couvidat²,

Kosovichev³

et al. 2001

The Astrophysical Journal

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165

152

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Three helioseismic instruments on the Solar and Heliospheric Observatory have observed the Sun almost continuously since early 1996. This has led to detailed study of the biases induced by the instruments that measure intensity or Doppler velocity variation. Photospheric turbulence hardly influences the tiny signature of conditions in the energy-generating core in the low-order modes, which are therefore very informative. We use sound-speed and density profiles inferred from GOLF and MDI data including these modes, together with recent improvements to stellar model computations, to build a spherically symmetric seismically adjusted model in agreement with the observations. The model is in hydrostatic and thermal balance and produces the present observed luminosity. In constructing the model, we adopt the best physics available, although we adjust some fundamental ingredients, well within the commonly estimated errors, such as the p-p reaction rate (ϩ1%) and the heavy-element abundance (ϩ3.5%); we also examine the sensitivity of the density profile to the nuclear reaction rates. Then, we deduce the corresponding emitted neutrino fluxes and consequently demonstrate that it is unlikely that the deficit of the neutrino fluxes measured on Earth can be explained by a spherically symmetric classical model without neutrino flavor transitions. Finally, we discuss the limitations of our results and future developments.

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Section: Emitted Neutrino Fluxes and Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Solar Neutrino Emission Deduced from a Seismic Model

Turck‐Chièze¹,

Couvidat²,

Kosovichev³

et al. 2001

The Astrophysical Journal

Self Cite

165

152

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“…Turck-Chièze et al 2001a;Turck-Chièze & Talon 2008). Recent analyses of the solar spectrum have led to substantial revisions of the solar abundances, particularly of oxygen, carbon, and nitrogen (for a review, see Asplund 2005).…”

Section: Introductionmentioning

confidence: 99%

On the opacity change required to compensate for the revised solar composition

Christensen‐Dalsgaard

Mauro²,

Houdek³

et al. 2008

A&A

114

101

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Context. Recent revisions of the determination of the solar composition have resulted in solar models in marked disagreement with helioseismic inferences. Aims. The effect of the inferred composition change on the models is largely caused by the change in opacity. Thus, we wish to determine an intrinsic opacity change that would compensate for the revision to the composition. Methods. By comparing models computed with the old and revised compositions we determine the required opacity change. Models are computed with the opacity modified in this manner and used as reference in helioseismic inversions to determine the difference between the solar and model sound speed.Results. An opacity increase ranging between around 30 per cent close to the base of the convection zone and a few percent in the solar core leads to a sound-speed profile, for the revised composition, that is essentially indistinguishable from the original solar model. As a function of the logarithm of temperature this is well represented by a simple cubic fit. The physical realism of such a change remains debatable, however.

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“…Using this probe as a reference, constant progress has been noticed on the determination of these fluxes (Turck-Chieze et al 1988, Turck-Chieze and Lopes 1993, Dzitko et al 1995, Brun, T-C k Morel, 1998, Brun, T-C & Zahn, 1999, Turck-Chieze et al 2001a, Turck-Chieze et al 2001b, Couvidat, Turck-Chieze & Kosovichev 2003.…”

Section: The Sun As a Laboratory For Emitted Neutrino Fluxesmentioning

confidence: 99%

MeV Neutrino Sources: The Sun and the Supernovae

Turck‐Chièze

2005

Highlights astron.

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Abstract.The two sources of MeV neutrinos, the Sun and the Supernovae are very interesting to study nowadays. Seismology aboard SoHO has properly constrained the solar emitted neutrino fluxes and consequently contributes to an unambiguous evidence of the solar neutrino oscillations. The main role of seismology stays nevertheless the description of the magneto-hydrodynamic processes and this progress provokes a renewal of the stellar discipline. Important results are noticed these three years, for the Sun. Future will be richer implying a large number of stars with an evident impact on supernovae and solar neutrino properties. The Two Sources of N e u t r i n o sThe two natural Neutrino MeV Sources, the Sun and the Supernovae, are studied with more and more interest as the richness of their plasma properties is inaccessible in laboratories. Nevertheless, the level of knowledge of these sources is extremely different. The solar internal structure is scrutinized for twenty years with two independent probes: neutrinos and acoustic modes. In the case of supernovae, the emitted neutrinos have been detected once only, for the Supernova 1987A. It is evident that these two sources are extremely different. If the Sun has a continuous emission of neutrinos, the emission coming from a supernova explosion is quasi instantaneous, with a peak of 0.025 s. Only 6.4 % of the produced solar energy is emitted by the neutrinos, though the main part of the released energy in a supernova explosion is contained in the neutrino emission. If the Sun emits neutrinos up to 14 MeV and has a well determined energy spectrum, the range of emission for the supernovae is large from 5 MeV to about 100 MeV. The impact of the different neutrino oscillation solutions on the supernova energy spectrum is high, mainly for the SNO detector, even the waiting statistics in Superkamiokande is higher, so there is extremely large interest to detect supernova neutrinos in the present observatories to put more constraints on the neutrino properties or on the explosion mechanism. The diversity of the supernovae (Heger et al. 2003) and consequently of the supernova explosions encourages also the study of the different supernova precursors. Supernovae la have initial mass below 8 M©, and final mass probably below 1.5 M©, Supernovae II have initial mass between 8 to 30 M©, final mass below 10 M©, Supernovae lb and c have initial mass above 30 M© and final mass always below 10 M©. With such a range in mass, questions on geometry, asphericity, rotation, metallicity have not a clear answer today.The geometry of stars and the mass loss processes are more under control at different stages of evolution, so there is a renewal in stellar structure, which 9 terms of use, available at https://www.cambridge.org/core/terms. https://doi

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Cited by 41 publications

References 17 publications

Solar Neutrino Emission Deduced from a Seismic Model

Solar Neutrino Emission Deduced from a Seismic Model

On the opacity change required to compensate for the revised solar composition

MeV Neutrino Sources: The Sun and the Supernovae

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