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Author Jimenez, R.; Pena-Garay, C.; Verde, L. url  doi
openurl 
  Title Is it possible to explore Peccei-Quinn axions from frequency-dependence radiation dimming? Type Journal Article
  Year 2011 Publication Physics Letters B Abbreviated Journal Phys. Lett. B  
  Volume 703 Issue 3 Pages 232-236  
  Keywords Axion; CF; White dwarf  
  Abstract (down) We explore how the Peccei-Quinn (PQ) axion parameter space can be constrained by the frequency-dependence dimming of radiation from astrophysical objects. To do so we perform accurate calculations of photon-axion conversion in the presence of a variable magnetic field. We propose several tests where the PQ axion parameter space can be explored with current and future astronomical surveys: the observed spectra of isolated neutron stars, occultations of background objects by white dwarfs and neutron stars, the light-curves of eclipsing binaries containing a white dwarf. We find that the lack of dimming of the light-curve of a detached eclipsing white dwarf binary recently observed, leads to relevant constraints on the photon-axion conversion. Current surveys designed for Earth-like planet searches are well matched to strengthen and improve the constraints on the PQ axion using astrophysical objects radiation dimming.  
  Address [Jimenez, R; Verde, L] Univ Barcelona IEEC UB, ICREA & ICC, Barcelona 08028, Spain, Email: jimenez@icc.ub.edu  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0370-2693 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000295198300005 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ elepoucu @ Serial 779  
Permanent link to this record
 

 
Author Minakata, H.; Pena-Garay, C. url  doi
openurl 
  Title Solar Neutrino Observables Sensitive to Matter Effects Type Journal Article
  Year 2012 Publication Advances in High Energy Physics Abbreviated Journal Adv. High. Energy Phys.  
  Volume 2012 Issue Pages 349686 - 15pp  
  Keywords  
  Abstract (down) We discuss constraints on the coefficient A(MSW) which is introduced to simulate the effect of weaker or stronger matter potential for electron neutrinos with the current and future solar neutrino data. The currently available solar neutrino data leads to a bound A(MSW) = 1.47(+0.54)(-0.42)((-0.82)(+1.88)) at 1 sigma (3 sigma) CL, which is consistent with the Standard Model prediction A(MSW) = 1. For weaker matter potential (A(MSW) < 1), the constraint which comes from the flat B-8 neutrino spectrum is already very tight, indicating the evidence for matter effects. However for stronger matter potential (A(MSW) > 1), the bound is milder and is dominated by the day-night asymmetry of B-8 neutrino flux recently observed by Super-Kamiokande. Among the list of observables of ongoing and future solar neutrino experiments, we find that (1) an improved precision of the day-night asymmetry of B-8 neutrinos, (2) precision measurements of the low-energy quasi-monoenergetic neutrinos, and (3) the detection of the upturn of the B-8 neutrino spectrum at low energies are the best choices to improve the bound on A(MSW).  
  Address [Minakata, H.] Tokyo Metropolitan Univ, Dept Phys, Hachioji, Tokyo 1920397, Japan, Email: hisakazu.minakata@gmail.com  
  Corporate Author Thesis  
  Publisher Hindawi Publishing Corporation Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1687-7357 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000311152600001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1234  
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Author Serenelli, A.; Scott, P.; Villante, F.L.; Vincent, A.C.; Asplund, M.; Basu, S.; Grevesse, N.; Pena-Garay, C. url  doi
openurl 
  Title Implications of solar wind measurements for solar models and composition Type Journal Article
  Year 2016 Publication Monthly Notices of the Royal Astronomical Society Abbreviated Journal Mon. Not. Roy. Astron. Soc.  
  Volume 463 Issue 1 Pages 2-9  
  Keywords neutrinos; Sun: abundances; Sun: helioseismology; Sun: interior  
  Abstract (down) We critically examine recent claims of a high solar metallicity by von Steiger & Zurbuchen (2016, vSZ16) based onin situ measurements of the solar wind, rather than the standard spectroscopically inferred abundances (Asplund et al. 2009, hereafter AGSS09). We test the claim by Vagnozzi et al. (2016) that a composition based on the solar wind enables one to construct a standard solar model in agreement with helioseismological observations and thus solve the decades-old solar modelling problem. We show that, although some helioseismological observables are improved compared to models computed with spectroscopic abundances, most are in fact worse. The high abundance of refractory elements leads to an overproduction of neutrinos, with a predicted B-8 flux that is nearly twice its observed value, and Be-7 and CNO fluxes that are experimentally ruled out at high confidence. A combined likelihood analysis shows that models using the vSZ16 abundances are worse than AGSS09 despite a higher metallicity. We also present astrophysical and spectroscopic arguments showing the vSZ16 composition to be an implausible representation of the solar interior, identifying the first ionization potential effect in the outer solar atmosphere and wind as the likely culprit.  
  Address [Serenelli, Aldo] Inst Space Sci IEEC CSIC, E-08193 Barcelona, Spain, Email: aldos@ice.csic.es  
  Corporate Author Thesis  
  Publisher Oxford Univ Press Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0035-8711 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000386464900001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 2842  
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Author Vinyoles, N.; Serenelli, A.M.; Villante, F.L.; Basu, S.; Bergstrom, J.; Gonzalez-Garcia, M.C.; Maltoni, M.; Pena-Garay, C.; Song, N.Q. url  doi
openurl 
  Title A New Generation of Standard Solar Models Type Journal Article
  Year 2017 Publication Astrophysical Journal Abbreviated Journal Astrophys. J.  
  Volume 835 Issue 2 Pages 202 - 16pp  
  Keywords neutrinos; Sun: abundances; Sun: Helioseismology; Sun: interior  
  Abstract (down) We compute a new generation of standard solar models (SSMs) that includes recent updates on some important nuclear reaction rates and a more consistent treatment of the equation of state. Models also include a novel and flexible treatment of opacity uncertainties based on opacity kernels, required in. light of recent theoretical and experimental works on radiative opacity. Two large sets of SSMs, each based on a different canonical set of solar abundances with high and low metallicity (Z), are computed to determine model uncertainties and correlations among different observables. We present detailed comparisons of high-and low-Z models against different ensembles of solar observables,. including solar neutrinos, surface helium abundance, depth of the. convective envelope, and sound speed profile. A global comparison, including all observables, yields a p-value of 2.7 sigma for the high-Z model and 4.7 sigma for the low-Z one. When the sound speed differences in the narrow region of 0.65 < r/R-circle dot < 0.70 are excluded from the analysis, results are 0.9 sigma and 3.0 sigma for high-and low-Z models respectively. These results show that. high-Z models agree well with solar data but have a systematic problem right below the bottom of the convective envelope linked to steepness of molecular weight and temperature gradients, and that low-Z models lead to a much more general disagreement with solar data. We also show that, while simple parametrizations of opacity uncertainties can strongly alleviate the solar abundance problem, they are insufficient to substantially improve the agreement of SSMs with helioseismic data beyond that obtained for high-Z models due to the intrinsic correlations of theoretical predictions.  
  Address [Vinyoles, Nuria; Serenelli, Aldo M.] CSIC IEEC, Inst Ciencies Espai, Campus UAB,Carrer Can Magrans S-N, E-08193 Barcelona, Spain, Email: vinyoles@ice.csic.es;  
  Corporate Author Thesis  
  Publisher Iop Publishing Ltd Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0004-637x ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000401145700018 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3145  
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Author Antonelli, V.; Miramonti, L.; Pena-Garay, C.; Serenelli, A. url  doi
openurl 
  Title Solar Neutrinos Type Journal Article
  Year 2013 Publication Advances in High Energy Physics Abbreviated Journal Adv. High. Energy Phys.  
  Volume 2013 Issue Pages 351926 - 34pp  
  Keywords  
  Abstract (down) The study of solar neutrinos has given a fundamental contribution both to astroparticle and to elementary particle physics, offering an ideal test of solar models and offering at the same time relevant indications on the fundamental interactions among particles. After reviewing the striking results of the last two decades, which were determinant to solve the long standing solar neutrino puzzle and refine the Standard Solar Model, we focus our attention on the more recent results in this field and on the experiments presently running or planned for the near future. The main focus at the moment is to improve the knowledge of the mass and mixing pattern and especially to study in detail the lowest energy part of the spectrum, which represents most of the solar neutrino spectrum but is still a partially unexplored realm. We discuss this research project and the way in which present and future experiments could contribute to make the theoretical framework more complete and stable, understanding the origin of some “anomalies” that seem to emerge from the data and contributing to answer some present questions, like the exact mechanism of the vacuum to matter transition and the solution of the so-called solar metallicity problem.  
  Address Univ Milan, Dipartimento Fis, I-20133 Milan, Italy, Email: vito.antonelli@mi.infn.it  
  Corporate Author Thesis  
  Publisher Hindawi Publishing Corporation Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1687-7357 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000316881700001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1392  
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