Suchergebnisse

While standard solar model (SSM) predictions depend on approximately 20 input parameters, SSM neutrino flux predictions are strongly correlated with a single model output parameter, the core temperature T-c. Consequently, one can extract physics from solar neutrino flux measurements while minimizing the consequences of SSM uncertainties, by studying flux ratios with appropriate power-law weightings tuned to cancel this T-c dependence. We reexamine an idea for constraining the primordial C + N content of the solar core from a ratio of CN-cycle O-15 to pp-chain B-8 neutrino fluxes, showing that non-nuclear SSM uncertainties in the ratio are small and effectively governed by a single parameter, the diffusion coefficient. We point out that measurements of both CN-I cycle neutrino branches-O-15 and N-13 beta-decay-could, in principle, lead to separate determinations of the core C and N abundances, due to out-of-equilibrium CN-cycle burning in the cooler outer layers of the solar core. Finally, we show that the strategy of constructing "minimum uncertainty" neutrino flux ratios can also test other properties of the SSM. In particular, we demonstrate that a weighted ratio of Be-7 and B-8 fluxes constrains a product of S-factors to the same precision currently possible with laboratory data. ; A. M. S. is partially supported by the European Union International Reintegration No. PIRG-GA-2009-247732, the MICINN Grant No. AYA2011-24704, by the ESF EUROCORES Program EuroGENESIS (MICINN Grant No. EUI2009-04170), by SGR Grants of the Generalitat de Catalunya and by the EU-FEDER funds. C. P.-G. is supported in part by the Spanish MICINN Grants No. FPA-2007-60323 and No. FPA2011-29678, the Generalitat Valenciana Grant No. PROMETEO/2009/116 and the ITN INVISIBLES (Marie Curie Actions, PITN-GA-2011-289442). This work was supported in part by the U.S. DOE under Grants No. DE-SC00046548 (Berkeley) and No. DE-AC02-98CH10886 (LBL). W. H. thanks the INT and GSI for their hospitality while part of this work was done, and the Alexander von Humboldt Foundation for its support. ; Peer reviewed