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Solar Core Homology, Solar Neutrinos and Helioseismology  [PDF]
Sidney A. Bludman,Dallas C. Kennedy
Physics , 1995, DOI: 10.1086/178073
Abstract: Precise numerical standard solar models (SSMs) now agree with one another and with helioseismological observations in the convective and outer radiative zones. Nevertheless these models obscure how luminosity, neutrino production and g-mode core helioseismology depend on such inputs as opacity and nuclear cross sections. Although the Sun is not homologous, its inner core by itself is chemically evolved and almost homologous, because of its compactness, radiative energy transport, and ppI-dominated luminosity production. We apply luminosity-fixed homology transformations to the core to estimate theoretical uncertainties in the SSM and to obtain a broad class of non-SSMs, parametrized by central temperature and density and purely radiative energy transport in the core.
Helioseismology and solar neutrinos: an update  [PDF]
G. Fiorentini,B. Ricci,F. L. Villante
Physics , 2000, DOI: 10.1016/S0920-5632(01)01066-0
Abstract: We review recent advances concerning helioseismology, solar models and solar neutrinos. Particularly we address the following points: i) helioseismic tests of recent SSMs; ii) predictions of the Beryllium neutrino flux based on helioseismology; iii) helioseismic tests regarding the screening of nuclear reactions in the Sun.
Helioseismology, solar models and solar neutrinos  [PDF]
G. Fiorentini,B. Ricci
Physics , 1999, DOI: 10.1016/S0920-5632(99)00864-6
Abstract: We review recent advances concerning helioseismology, solar models and solar neutrinos. Particularly we shall address the following points: i) helioseismic tests of recent SSMs; ii)the accuracy of the helioseismic determination of the sound speed near the solar center; iii)predictions of neutrino fluxes based on helioseismology, (almost) independent of SSMs; iv)helioseismic tests of exotic solar models.
Helioseismology and solar neutrinos  [PDF]
J. Christensen-Dalsgaard
Physics , 1997,
Abstract: Helioseismology has provided very precise information about the solar internal sound speed and density throughout most of the solar interior. The results are generally quite close to the properties of standard solar models. Since the solar oscillation frequencies do not provide direct information about temperature and composition, the helioseismic results to not completely rule out an astrophysical solution to the discrepancy between the predicted and measured neutrino fluxes from the Sun. However, such a solution does appear rather implausible.
Solar neutrinos, helioseismology and the solar internal dynamics  [PDF]
S. Turck-Chieze,S. Couvidat
Physics , 2010, DOI: 10.1088/0034-4885/74/8/086901
Abstract: Neutrinos are fundamental particles ubiquitous in the Universe. Their properties remain elusive despite more than 50 years of intense research activity. In this review we remind the reader of the noticeable properties of these particles and of the stakes of the solar neutrino puzzle. The Standard Solar Model triggered persistent efforts in fundamental Physics to predict the solar neutrino fluxes, and its constantly evolving predictions have been regularly compared to the detected neutrino signals. Anticipating that this standard model could not reproduce the internal solar dynamics, a SEismic Solar Model was developed which enriched theoretical neutrino flux predictions with in situ observation of acoustic waves propagating in the Sun. This review reminds the historical steps, from the pioneering Homestake detection, the GALLEX- SAGE captures of the first pp neutrinos and emphasizes the importance of the Superkamiokande and SNO detectors to demonstrate that the solar-emitted electronic neutrinos are partially transformed into other neutrino flavors before reaching the Earth. The success of BOREXINO in detecting the 7 Be neutrino signal justifies the building of a new generation of detectors to measure the entire solar neutrino spectrum. A coherent picture emerged from neutrino physics and helioseismology. Today, new paradigms take shape: determining the masses of neutrinos and the research on the Sun is focusing on the dynamical aspects and on signature of dark matter. The third part of the review is dedicated to this prospect. The understanding of the crucial role of both rotation and magnetism in solar physics benefit from SoHO, SDO, and PICARD space observations. For now, the particle and stellar challenges seem decoupled, but this is only a superficial appearance. The development of asteroseismology shows the far-reaching impact of Neutrino and Stellar Astronomy.
Solar neutrinos as highlight of astroparticle physics  [PDF]
V. Berezinsky
Physics , 1997,
Abstract: Solar neutrinos are discussed in the light of the new data and of recent progress in helioseismology. Most attention is given to the new status of Standard Solar Models due to seismically measured density and sound speed in the inner solar core. The elementary particle solutions to the Solar Neutrino Problem and their observational signatures are discussed.
The Solar Core and Solar Neutrinos  [PDF]
Dallas C. Kennedy
Physics , 2000,
Abstract: The long-standing deficit of measured versus predicted solar neutrino fluxes is re-examined in light of possible astrophysical solutions. In the last decade, solar neutrino flux and helioseismic measurements have greatly strengthened the case for non-astrophysical solutions. But some model- independent tests remain open.
CN-Cycle Solar Neutrinos and Sun's Primordial Core Metalicity
Haxton, W. C.;Serenelli, A. M.
High Energy Physics - Phenomenology , 2008, DOI: 10.1086/591787
Abstract: We argue that it may be possible to exploit neutrinos from the CN cycle and pp chain to determine the primordial solar core abundances of C and N at an interesting level of precision. Such a measurement would allow a comparison of the Sun's deep interior composition with it surface, testing a key assumption of the standard solar model (SSM), a homogeneous zero-age Sun. It would also provide a cross-check on recent photospheric abundance determinations that have altered the once excellent agreement between the SSM and helioseismology. As further motivation, we discuss a speculative possibility in which photospheric abundance/helioseismology puzzle is connected with the solar-system metal differentiation that accompanied formation of the gaseous giant planets. The theoretical relationship between core C and N and the 13N and 15O solar neutrino fluxes can be made more precise (and more general) by making use of the Super-Kamiokande and SNO 8B neutrino capture rates, which calibrate the temperature of the solar core. The primordial C and N abundances can then be obtained from these neutrino fluxes and from a product of nuclear rates, with little residual solar model dependence. We describe some of the recent experimental advances that could allow this comparison to be made (theoretically) at about the 9% level, and note that this uncertainty may be reduced further due to ongoing work on the S-factor for 14N(p,gamma). The envisioned measurement might be possible in deep, large-volume detectors using organic scintillator, e.g., Borexino or SNO+
The solar energetic balance revisited by young solar analogs, helioseismology and neutrinos  [PDF]
Sylvaine Turck-Chieze,Laurent Piau,Sébastien Couvidat
Physics , 2011, DOI: 10.1088/2041-8205/731/2/L29
Abstract: The energetic balance of the Standard Solar Model (SSM) results from an equilibrium between nuclear energy production, energy transfer, and photospheric emission. In this letter, we derive an order of magnitude of several % for the loss of energy in kinetic energy, magnetic energy, and X or UV radiation during the whole solar lifetime from the observations of the present Sun. We also estimate the mass loss from the observations of young solar analogs which could reach up to 30% of the current mass. We deduce new models of the present Sun, their associated neutrino fluxes, and their internal sound-speed profile. This approach sheds quantitative lights on the disagreement between the sound speed obtained by helioseismology and the sound speed derived from the SSM including the updated photospheric CNO abundances, based on recent observations. We conclude that about 20% of the present discrepancy could come from the incorrect description of the early phases of the Sun, its activity, its initial mass and mass-loss history. This study has obvious consequences on the solar system formation and the early evolution of the closest planets.
CN Neutrinos and the Sun's Primordial Core Metalicity
Haxton, W. C.
High Energy Physics - Phenomenology , 2008, DOI: 10.1088/1742-6596/173/1/012014
Abstract: I discuss the use of neutrinos from the CN cycle and pp chain to constrain the primordial solar core abundances of C and N at an interesting level of precision. A comparison of the Sun's deep interior and surface compositions would test a key assumption of the standard solar model (SSM), a homogeneous zero-age Sun. It would also provide a cross-check on recent photospheric abundance determinations that have altered the once excellent agreement between the SSM and helioseismology. Motivated by the discrepancy between convective-zone abundances and helioseismology, I discuss the possibility that a two-zone Sun could emerge from late-stage metal differentiation in the solar nebula connected with formation of the gaseous giant planets.
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