Schwetz, T., Tortola, M., & Valle, J. W. F. (2011). Where we are on theta(13): addendum to 'Global neutrino data and recent reactor fluxes: status of three-flavor oscillation parameters'. New J. Phys., 13, 109401–5pp.
Abstract: In this addendum to Schwetz et al (2011 New J. Phys. 13 063004), we consider the recent results from long-baseline nu(mu) -> nu(e) searches at the Tokai to Kamioka (T2K) and Main Injector Neutrino Oscillation Search (MINOS) experiments and investigate their implications for the mixing angle theta(13) and the leptonic Dirac CP phase delta. By combining the 2.5 sigma indication for a nonzero value of theta(13) coming from the T2K data with global neutrino oscillation data, we obtain a significance for theta(13) > 0 of about 3 sigma with best fit points sin(2) theta(13) = 0.013 (0.016) for normal (inverted) neutrino mass ordering. These results depend somewhat on assumptions concerning the analysis of reactor neutrino data.
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Semikoz, V. B., & Valle, J. W. F. (2011). Chern-Simons anomaly as polarization effect. J. Cosmol. Astropart. Phys., 11(11), 048.
Abstract: The parity violating, Chern-Simons term in the epoch before the electroweak phase transition can be interpreted as a polarization effect associated to massless right-handed electrons (positrons) in the presence of a large-scale seed hypermagnetic field. We reconfirm the viability of a unified seed field scenario relating the cosmological baryon asymmetry and the origin of the protogalactic large-scale magnetic fields observed in astronomy.
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Restrepo, D., Taoso, M., Valle, J. W. F., & Zapata, O. (2012). Gravitino dark matter and neutrino masses with bilinear R-parity violation. Phys. Rev. D, 85(2), 023523–7pp.
Abstract: Bilinear R-parity violation provides an attractive origin for neutrino masses and mixings. In such schemes the gravitino is a viable decaying dark matter particle whose R-parity violating decays lead to monochromatic photons with rates accessible to astrophysical observations. We determine the parameter region allowed by gamma-ray line searches, dark matter relic abundance, and neutrino oscillation data, obtaining a limit on the gravitino mass m((G) over tilde) less than or similar to 1-10 GeV corresponding to a relatively low reheat temperature T-R less than or similar to few x 10(7)-10(8) GeV. Neutrino mass and mixing parameters may be reconstructed at accelerator experiments like the Large Hadron Collider.
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Garces, E. A., Miranda, O. G., Tortola, M., & Valle, J. W. F. (2012). Low-energy neutrino-electron scattering as a standard model probe: The potential of LENA as case study. Phys. Rev. D, 85(7), 073006–6pp.
Abstract: Several proposals for studying neutrinos with large detectors are currently under discussion. We suggest that they could provide a precise measurement of the electroweak mixing angle as well as a probe for new physics, such as nonstandard neutrino interactions, and the electroweak gauge structure. We illustrate this explicitly for the case of the LENA proposal, either with an artificial radioactive source or by using the solar neutrino flux.
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Dorame, L., Meloni, D., Morisi, S., Peinado, E., & Valle, J. W. F. (2012). Constraining neutrinoless double beta decay. Nucl. Phys. B, 861(3), 259–270.
Abstract: A class of discrete flavor-symmetry-based models predicts constrained neutrino mass matrix schemes that lead to specific neutrino mass sum-rules (MSR). We show how these theories may constrain the absolute scale of neutrino mass, leading in most of the cases to a lower bound on the neutrinoless double beta decay effective amplitude.
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