Fernandez-Martinez, E., Giordano, G., Mena, O., & Mocioiu, I. (2010). Atmospheric neutrinos in ice and measurement of neutrino oscillation parameters. Phys. Rev. D, 82(9), 093011–7pp.
Abstract: The main goal of the IceCube Deep Core array is to search for neutrinos of astrophysical origins. Atmospheric neutrinos are commonly considered as a background for these searches. We show that the very high statistics atmospheric neutrino data can be used to obtain precise measurements of the main oscillation parameters.
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Lopez Honorez, L., Mena, O., & Panotopoulos, G. (2010). Higher-order coupled quintessence. Phys. Rev. D, 82(12), 123525–7pp.
Abstract: We study a coupled quintessence model in which the interaction with the dark-matter sector is a function of the quintessence potential. Such a coupling can arise from a field dependent mass term for the dark-matter field. The dynamical analysis of a standard quintessence potential coupled with the interaction explored here shows that the system possesses a late-time accelerated attractor. In light of these results, we perform a fit to the most recent Supernovae Ia, Cosmic Microwave Background, and Baryon Acoustic Oscillation data sets. Constraints arising from weak equivalence principle violation arguments are also discussed.
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Pandolfi, S., Giusarma, E., Kolb, E. W., Lattanzi, M., Melchiorri, A., Mena, O., et al. (2010). Impact of general reionization scenarios on extraction of inflationary parameters. Phys. Rev. D, 82(12), 123527–10pp.
Abstract: Determination of whether the Harrison-Zel'dovich spectrum for primordial scalar perturbations is consistent with observations is sensitive to assumptions about the reionization scenario. In light of this result, we revisit constraints on inflationary models using more general reionization scenarios. While the bounds on the tensor-to-scalar ratio are largely unmodified, when different reionization schemes are addressed, hybrid models are back into the inflationary game. In the general reionization picture, we reconstruct both the shape and amplitude of the inflaton potential. We discuss how relaxing the simple reionization restriction affects the reconstruction of the potential through the changes in the constraints on the spectral index, the tensor-to-scalar ratio and the running of the spectral index. We also find that the inclusion of other Cosmic Microwave Background data in addition to the Wilkinson Microwave Anisotropy probe data excludes the very flat potentials typical of models in which the inflationary evolution reaches a late-time attractor, as a consequence of the fact that the running of the spectral index is constrained to be different from zero at 99% confidence level.
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Giordano, G., Mena, O., & Mocioiu, I. (2010). Atmospheric neutrino oscillations and tau neutrinos in ice. Phys. Rev. D, 81(11), 113008–5pp.
Abstract: The main goal of the IceCube Deep Core Array is to search for neutrinos of astrophysical origins. Atmospheric neutrinos are commonly considered as a background for these searches. We show here that cascade measurements in the Ice Cube Deep Core Array can provide strong evidence for tau neutrino appearance in atmospheric neutrino oscillations. Controlling systematic uncertainties will be the limiting factor in the analysis. A careful study of these tau neutrinos is crucial, since they constitute an irreducible background for astrophysical neutrino detection.
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Razzaque, S., Jean, P., & Mena, O. (2010). High energy neutrinos from novae in symbiotic binaries: The case of V407 Cygni. Phys. Rev. D, 82(12), 123012–5pp.
Abstract: Detection of high-energy (>= 100 MeV) gamma rays by the Fermi Large Area Telescope from a nova in the symbiotic binary system V407 Cygni has opened the possibility of high-energy neutrino detection from this type of source. A thermonuclear explosion on the white dwarf surface sets off a nova shell in motion that expands and slows down in a dense surrounding medium provided by the red giant companion. Particles are accelerated in the shocks of the shell and interact with the surrounding medium to produce observed gamma rays. We show that proton-proton interaction, which is most likely responsible for producing gamma rays via neutral pion decay, produces >= 0:1 GeV neutrinos that can be detected by the current and future experiments at >= 10 GeV.
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