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Neutrino oscillation experiments in the past decades have greatly improved our knowledge on neutrinos by measuring the fundamental neutrino parameters. The ongoing and upcoming neutrino oscillation experiments are intended to pin down the neutrino mass hierarchy and to discover the leptonic CP violation. By means of neutrino oscillograms, we analyze the impact of nonstandard neutrino interactions on neutrino oscillations in Earth matter. The standard neutrino oscillation probabilities may be signifi-cantly changed by nonstandard interaction parameters, and, in particular, the CP-violating effects in the energy range E = 1-20 GeV are greatly enhanced. In addition, the event rates of muon neutrinos in the proposed huge atmospheric neutrino experiment, PINGU at the South Pole, have been estimated in the presence of nonstandard neutrino interactions. It has been found that the PINGU experiment has very good sensitivities to the nonstandard neutrino interaction parameters. [ABSTRACT FROM AUTHOR]

Abstract: In this plenary talk, we review the status of non-standard neutrino interactions (NSIs). First, we give a brief introduction to neutrino flavor transitions with NSIs based on the standard paradigm of neutrino oscillations. Then, we discuss alternative scenarios for neutrino flavor transitions such as neutrino decoherence, neutrino decay, and NSIs. Second, we investigate NSIs with three neutrino flavors. In general, we introduce production and detection NSIs, including the so-called zero-distance effect, and matter NSIs. In addition, we study mappings and approximate formulas for NSIs. Third, we present a brief account of theoretical models for NSIs. Fourth and most important, we investigate in detail the phenomenology of NSIs based on different types of data from neutrino experiments. Fifth, we give some phenomenological bounds on both matter and production/detection NSIs as well as we present sensitivity and discovery reach of NSIs at future experiments. Finally, we present a summary and state our conclusions. [Copyright &y& Elsevier]

The discovery of leptonic CP violation is one of the primary goals of next-generation neutrino oscillation experiments, which is feasible due to the recent measurement of a relatively large leptonic mixing angle θ13. We suggest two new working observables ΔAmαβ = max [Acpαβ(ƍ)] - min[Acpαβ(ƍ)] and ΔAcpαβ(ƍ) = Acpαβ(ƍ) -- Acpαβ(0) to describe the CP-violating effects in long-baseline and atmospheric neutrino oscillation experiments. The former signifies the experimental sensitivity to the leptonic Dirac CP-violating phase ƍ and can be used to optimize the experimental setup, while the latter measures the intrinsic leptonic CP violation and can be used to extract ƍ directly from the experimental observations. Both analytical and numerical analyses are carried out to illustrate their main features. It turns out that an intense neutrino beam with sub-GeV energies and a baseline of a few 100 km may serve as an optimal experimental setup for probing leptonic CP violation. [ABSTRACT FROM AUTHOR]

Since the smallest leptonic mixing angle θ13 has been measured to be relatively large, it is quite promising to constrain or determine the leptonic Dirac CP-violating phase δ in future neutrino oscillation experiments. Given some typical values of δ = π/2, π, and 3π/2 at the low energy scale, as well as current experimental results of the other neutrino parameters, we perform a systematic study of radiative corrections to δ by using the one-loop renormalization group equations in the minimal supersymmetric standard model and the universal extra-dimensional model. It turns out that δ is rather stable against radiative corrections in both models, except for the minimal supersymmetric standard model with a very large value of tanβ. Both cases of Majorana and Dirac neutrinos are discussed. In addition, we use the preliminary indication of δ = (1.08+0.28-31)π or δ = (1.67+0.37-0.77)π from the latest global-fit analyses of data from neutrino oscillation experiments to illustrate how it will be modified by radiative corrections. [ABSTRACT FROM AUTHOR]

With the advent of the recent measurements in neutrino physics, we investigate the role of high-energy neutrino flux ratios at neutrino telescopes for die possibility of determining the leptonic CP-violating phase δ and the underlying pattern of the leptonic mixing matrix. We find that the flux ratios show a dependence of O(10%) on the CP-violating phase, and for optimistic uncertainties on the flux ratios less than 10%, they can be used to distinguish between CP-conserving and CP-violating values of the phase at 2σ in a nonvanishing interval around the maximal value |δ| = π/2. [ABSTRACT FROM AUTHOR]

Several letters to the editor are presented in response to articles from previous issues, including a report on stupidity from the March 30, 2013 issue, an article about the applications of synthetic biology from the March 30, 2013 issue, and the special February 2, 2013 issue on sleep and dreaming.

Several letters to the editor are presented in response to articles from previous issues, including a report about a study linking transgenic corn to cancer from the December 8, 2012 issue, an article by Marion Nestle about the end of a tax on fatty foods in Denmark from the November 24, 2012 issue, and an article about the impact of Superstorm Sandy on New York City from the November 10, 2012 issue.

Several letters to the editor are presented in response to articles in previous issues including one on a DebtRank analysis of banks in the August 11, 2012 issue, one of a graph showing income inequality in the U.S. since 1920 in the July 28, 2012 issue, and one on the U.S. mortgage crisis by Philip Penton in the July 7, 2012 issue.

We investigate possible tests of CPT invariance on the level of event rates at neutrino factories. We do not assume any specific model, but phenomenological differences in the neutrino-antineutrino masses and mixing angles in a Lorentz invariance preserving context, which could be induced by physics beyond the Standard Model. We especially focus on the muon neutrino and antineutrino disappearance channels in order to obtain constraints on the neutrino-antineutrino mass and mixing angle differences. In a typical neutrino factory setup simulation, we find, for example, that &z.sfnc;m3 − m3&z.sfnc; $ˇ1.9 · 10−4 eV and &z.sfnc;≡23 − ≡23&z.sfnc;≲ 2°. [Copyright &y& Elsevier]

In this Letter, we show the effects on the transition probabilities for neutrino oscillations due to a thin constant density layer perturbation added to an arbitrary matter density profile. In the case of two neutrino flavors, we calculate the effects both analytically and numerically, whereas in the case of three neutrino flavors, we perform the studies purely numerically. As an realistic example we consider the effects of the Earth's atmosphere when added to the Earth's matter density profile on the neutrino oscillation transition probabilities for atmospheric neutrinos.

We investigate a nonrelativistic model of tetraquarks, which are assumed to be compact and to consist of diquark-antidiquark pairs. We fit, for the first time, basically all currently known values for the measured masses of 45 mesons, including both charmed and bottom mesons, to the model and predict masses of tetraquarks as well as diquarks. In particular, we find masses of four axial-vector diquarks, i.e., qc, cc, qb, and bb, where q=u, d, and 24 ground-state tetraquarks, including both heavy-light tetraquarks (qcqc and qbqb) and heavy tetraquarks (cccc and bbbb). In general, our results for the masses of qbqb, cccc, and bbbb are largely comparable with other reported results, whereas our results for the masses of qcqc are slightly larger than what has been found earlier. Finally, we identify some of the obtained predictions for masses of tetraquarks with masses of experimental tetraquark candidates, and especially, we find that ψ(4660), Zb(10610), and Zb(10650) could be described by the model. [ABSTRACT FROM AUTHOR]

We investigate possible interactions between neutrinos and massive scalar bosons via gϕννϕ (or massive vector bosons via gVνγμνVμ) and explore the allowed parameter space of the coupling constant gϕ (or gV) and the scalar (or vector) boson mass mϕ (or mV) by requiring that these secret neutrino interactions (SNIs) should not spoil the success of big bang nucleosynthesis (BBN). Incorporating the SNIs into the evolution of the early Universe in the BBN era, we numerically solve the Boltzmann equations and compare the predictions for the abundances of light elements with observations. It turns out that the constraint on gϕ and mϕ in the scalar-boson case is rather weak, due to a small number of degrees of freedom (d.o.f.). However, in the vector-boson case, the most stringent bound on the coupling gV≲6×10-10 at 95% confidence level is obtained for mV≃1 MeV, while the bound becomes much weaker gV≲8×10-6 for smaller masses mV≲10-4 MeV. Moreover, we discuss in some detail how the SNIs affect the cosmological evolution and the abundances of the lightest elements. [ABSTRACT FROM AUTHOR]

We investigate compact halos of sterile-neutrino dark matter and examine observable signatures with respect to neutrino and photon emission. Primarily, we consider two cases: primordial black-hole halos and ultracompact minihalos. In both cases, we find that there exists a broad range of possible parameter choices such that detection in the near future with x-ray and gamma-ray telescopes might be well possible. In fact, for energies above 10 TeV, the neutrino telescope IceCube would be a splendid detection machine for such macroscopic dark-matter candidates. [ABSTRACT FROM AUTHOR]

We comment positively on the recent article "Seesaw mechanism with Occam's razor" [K. Harigaya et al. Phys. Rev. D 86, 013002 (2012).] by Harigaya, Ibe, and Yanagida. In this article, the authors are using the principle of Occam's razor in neutrino physics--a principle that should be applied more often in science in general. At the end, we also discuss the Bayesian method in statistics, in which Occam's razor is naturally built in. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to an article about the discovery of a boson, most likely the Higgs, along with a possible successor to the Large Hadron Collider, in the November 10, 2012 issue.

A letter to the editor is presented in response to an article about neutrinos, in the September 8, 2012 issue.

We summarize the results of Ref. [M. Blennow, T. Ohlsson and H. Snellman, Phys. Rev. D 69 (2004) 073006, hep-ph/0311098] in which we determine the effects of three flavor mixing on the day-night asymmetry in the flux of solar neutrinos. Analytic methods are used to determine the difference in the day and night solar electron neutrino survival probabilites and numerical methods are used to determine the effect of three flavor mixing at detectors. [Copyright &y& Elsevier]

Non-Abelian discrete symmetries provide an interesting opportunity to address the flavor puzzle in the lepton sector. However, the number of currently viable models based on such symmetries is rather large. High-precision measurements of the leptonic mixing parameters by future neutrino experiments, including ESSnuSB, T2HK, DUNE, and JUNO, will be crucial to test such models. We show that the complementarity among these experiments offers a powerful tool for narrowing down this broad class of lepton flavor models. [ABSTRACT FROM AUTHOR]

The prospects to detect neutrinos from the Sun arising from dark matter annihilations in the core of the Sun are reviewed. Emphasis is placed on new work investigating the effects of neutrino oscillations on the expected neutrino fluxes. [Copyright &y& Elsevier]

We investigate monoenergetic gamma-ray signatures from annihilations of dark matter comprised of Z1, the first Kaluza-Klein (KK) excitation of the Z boson in a nonminimal universal extra dimensions (UED) model. The self interactions of the non-Abelian Z1gauge boson give rise to a large number of contributing Feynman diagrams that do not exist for annihilations of the Abelian gauge boson ß1, which is the standard Kaluza-Klein dark matter (KKDM) candidate. We find that the annihilation rate is indeed considerably larger for the Z1 than for the B1. Even though relic density calculations indicate that the mass of the Z1 should be larger than the mass of the B1, the predicted monoenergetic gamma fluxes are of the same order of magnitude. We compare our results to existing experimental limits, as well as to future sensitivities, for image air Cherenkov telescopes, and we find that the limits are reached already with a moderately large boost factor. The realistic prospects for detection depend on the experimental energy resolution. [ABSTRACT FROM AUTHOR]