De Romeri, V., Fernandez-Martinez, E., & Sorel, M. (2016). Neutrino oscillations at DUNE with improved energy reconstruction. J. High Energy Phys., 09(9), 030–25pp.
Abstract: We study the physics reach of the long-baseline oscillation analysis of the DUNE experiment when realistic simulations are used to estimate its neutrino energy reconstruction capabilities. Our studies indicate that significant improvements in energy resolution compared to what is customarily assumed are plausible. This improved energy resolution can increase the sensitivity to leptonic CP violation in two ways. On the one hand, the CP-violating term in the oscillation probability has a characteristic energy dependence that can be better reproduced. On the other hand, the second oscillation maximum, especially sensitive to delta(CP), is better reconstructed. These effects lead to a significant improvement in the fraction of values of delta(CP) for which a 5 sigma discovery of leptonic CP-violation would be possible. The precision of the delta(CP) measurement could also be greatly enhanced, with a reduction of the maximum uncertainties from 26 degrees to 18 degrees for a 300 MW.kt.yr exposure. We therefore believe that this potential gain in physics reach merits further investigations of the detector performance achievable in DUNE.
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Salvado, J., Mena, O., Palomares-Ruiz, S., & Rius, N. (2017). Non-standard interactions with high-energy atmospheric neutrinos at IceCube. J. High Energy Phys., 01(1), 141–30pp.
Abstract: Non-standard interactions in the propagation of neutrinos in matter can lead to significant deviations from expectations within the standard neutrino oscillation framework and atmospheric neutrino detectors have been considered to set constraints. However, most previous works have focused on relatively low-energy atmospheric neutrino data. Here, we consider the one-year high-energy through-going muon data in IceCube, which has been already used to search for light sterile neutrinos, to constrain new interactions in the μtau-sector. In our analysis we include several systematic uncertainties on both, the atmospheric neutrino flux and on the detector properties, which are accounted for via nuisance parameters. After considering different primary cosmic-ray spectra and hadronic interaction models, we improve over previous analysis by using the latest data and showing that systematics currently affect very little the bound on the off-diagonal epsilon(mu tau), with the 90% credible interval given by -6.0 x 10(-3) < epsilon(mu tau) < 5.4 x 10(-3), comparable to previous results. In addition, we also estimate the expected sensitivity after 10 years of collected data in IceCube and study the precision at which non-standard parameters could be determined for the case of epsilon(mu tau) near its current bound.
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Alcaide, J., Das, D., & Santamaria, A. (2017). A model of neutrino mass and dark matter with large neutrinoless double beta decay. J. High Energy Phys., 04(4), 049–21pp.
Abstract: We propose a model where neutrino masses are generated at three loop order but neutrinoless double beta decay occurs at one loop. Thus we can have large neutrinoless double beta decay observable in the future experiments even when the neutrino masses are very small. The model receives strong constraints from the neutrino data and lepton flavor violating decays, which substantially reduces the number of free parameters. Our model also opens up the possibility of having several new scalars below the TeV regime, which can be explored at the collider experiments. Additionally, our model also has an unbroken Z(2) symmetry which allows us to identify a viable Dark Matter candidate.
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Pich, A., Rosell, I., Santos, J., & Sanz-Cillero, J. J. (2017). Fingerprints of heavy scales in electroweak effective Lagrangians. J. High Energy Phys., 04(4), 012–60pp.
Abstract: The couplings of the electroweak effective theory contain information on the heavy-mass scales which are no-longer present in the low-energy Lagrangian. We build a general effective Lagrangian, implementing the electroweak chiral symmetry breaking SU(2)(L) circle times SU(2)(R) -> SU(2)(L+R), which couples the known particle fields to heavier states with bosonic quantum numbers J(P) = 0(+/-) and 1(+/-). We consider colour-singlet heavy fields that are in singlet or triplet representations of the electroweak group. Integrating out these heavy scales, we analyze the pattern of low-energy couplings among the light fields which are generated by the massive states. We adopt a generic non-linear realization of the electroweak symmetry breaking with a singlet Higgs, without making any assumption about its possible doublet structure. Special attention is given to the different possible descriptions of massive spin-1 fields and the differences arising from naive implementations of these formalisms, showing their full equivalence once a proper short-distance behaviour is required.
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Reig, M., Valle, J. W. F., & Vaquera-Araujo, C. A. (2017). Three-family left-right symmetry with low-scale seesaw mechanism. J. High Energy Phys., 05(5), 100–10pp.
Abstract: We suggest a new left-right symmetric model implementing a low-scale see-saw mechanism in which quantum consistency requires three families of fermions. The symmetry breaking route to the Standard Model determines the profile of the “next” expected new physics, characterized either by the simplest left-right gauge symmetry or by the 3-3-1 scenario. The resulting Z' gauge bosons can be probed at the LHC and provide a production portal for the right-handed neutrinos. On the other hand, its flavor changing interactions would affect the K, D and B neutral meson systems.
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