Atmospheric neutrino spectrum reconstruction with JUNO

The atmospheric neutrino flux represents a continuous source that can be exploited to infer properties about Cosmic Rays and neutrino oscillation physics. The JUNO observatory, a 20 kt liquid scintillator currently under construction in China, will be able to detect atmospheric neutrinos , given the large fiducial volume and the excellent energy resolution. The light produced in neutrino interactions will be collected by a double-system of photosensors: about 18.000 20" PMTs and about 25.000 3" PMTs. The rock overburden above the experimental hall is around 700 m and the experiment is expected to complete construction in 2021. In this study, the JUNO performances in reconstructing the atmospheric neutrino spectrum have been evaluated. The different time evolution of scintillation light on the PMTs allows to discriminate the flavor of the primary neutrinos. To reconstruct the time pattern of events, the signals from 3" PMTs only have been used, because of the small time resolution. A probabilistic unfolding method has been used, in order to infer the primary neutrino energy spectrum by looking at the detector output. The simulated spectrum has been reconstructed between 100 MeV and 10 GeV, showing a great potential of the detector in the atmospheric low energy region. The uncertainties on the final flux, including both statistic and the systematic contributions, range between 10% and 25%, with the best performances obtained at the GeV.Comment: 7 pages, 7 figures. Proceeding for a parallel talk at the 2019 EPS-HEP Conference. arXiv admin note: text overlap with arXiv:1901.1034

Dopamine Transporter Imaging in Psychogenic Parkinsonism and Neurodegenerative Parkinsonism with Psychogenic Overlay: A Report of Three Cases

Background: Differentiating psychogenic parkinsonism from neurodegenerative Parkinson's disease (PD) with psychogenic features is a diagnostic challenge. Case report: We report a detailed longitudinal clinical description of three cases presenting with suspected psychogenic parkinsonism. Dopamine transporter single-photon emission computed tomography (DAT-SPECT) was used as a supplemental diagnostic study and influenced clinical management. Discussion: DAT-SPECT quantified the integrity of the striatal dopaminergic system in these cases of clinically uncertain parkinsonism and supported clinical decision-making

Robust entanglement of a micromechanical resonator with output optical fields

We perform an analysis of the optomechanical entanglement between the experimentally detectable output field of an optical cavity and a vibrating cavity end-mirror. We show that by a proper choice of the readout (mainly by a proper choice of detection bandwidth) one can not only detect the already predicted intracavity entanglement but also optimize and increase it. This entanglement is explained as being generated by a scattering process owing to which strong quantum correlations between the mirror and the optical Stokes sideband are created. All-optical entanglement between scattered sidebands is also predicted and it is shown that the mechanical resonator and the two sideband modes form a fully tripartite-entangled system capable of providing practicable and robust solutions for continuous variable quantum communication protocols

Black swans or dragon kings? A simple test for deviations from the power law

We develop a simple test for deviations from power law tails, which is based on the asymptotic properties of the empirical distribution function. We use this test to answer the question whether great natural disasters, financial crashes or electricity price spikes should be classified as dragon kings or 'only' as black swans

The critical behavior of 3D Ising glass models: universality and scaling corrections

We perform high-statistics Monte Carlo simulations of three three-dimensional Ising spin-glass models: the +-J Ising model for two values of the disorder parameter p, p=1/2 and p=0.7, and the bond-diluted +-J model for bond-occupation probability p_b = 0.45. A finite-size scaling analysis of the quartic cumulants at the critical point shows conclusively that these models belong to the same universality class and allows us to estimate the scaling-correction exponent omega related to the leading irrelevant operator, omega=1.0(1). We also determine the critical exponents nu and eta. Taking into account the scaling corrections, we obtain nu=2.53(8) and eta=-0.384(9).Comment: 9 pages, published versio

Modeling lightning-NOx chemistry on a sub-grid scale in a global chemical transport model

For the first time, a plume-in-grid approach is implemented in a chemical transport model (CTM) to parameterize the effects of the nonlinear reactions occurring within high concentrated NO_<i>x</i> plumes from lightning NO_<i>x</i> emissions (LNO_<i>x</i>) in the upper troposphere. It is characterized by a set of parameters including the plume lifetime, the effective reaction rate constant related to NO_<i>x</i>–O₃ chemical interactions, and the fractions of NO_<i>x</i> conversion into HNO₃ within the plume. Parameter estimates were made using the Dynamical Simple Model of Atmospheric Chemical Complexity (DSMACC) box model, simple plume dispersion simulations, and the 3-D Meso-NH (non-hydrostatic mesoscale atmospheric model). In order to assess the impact of the LNO_<i>x</i> plume approach on the NO_<i>x</i> and O₃ distributions on a large scale, simulations for the year 2006 were performed using the GEOS-Chem global model with a horizontal resolution of 2° × 2.5°. The implementation of the LNO_<i>x</i> parameterization implies an NO_<i>x</i> and O₃ decrease on a large scale over the region characterized by a strong lightning activity (up to 25 and 8 %, respectively, over central Africa in July) and a relative increase downwind of LNO_<i>x</i> emissions (up to 18 and 2 % for NO_<i>x</i> and O₃, respectively, in July). The calculated variability in NO_<i>x</i> and O₃ mixing ratios around the mean value according to the known uncertainties in the parameter estimates is at a maximum over continental tropical regions with ΔNO_<i>x</i> [−33.1, +29.7] ppt and ΔO₃ [−1.56, +2.16] ppb, in January, and ΔNO_<i>x</i> [−14.3, +21] ppt and ΔO₃ [−1.18, +1.93] ppb, in July, mainly depending on the determination of the diffusion properties of the atmosphere and the initial NO mixing ratio injected by lightning. This approach allows us (i) to reproduce a more realistic lightning NO_<i>x</i> chemistry leading to better NO_<i>x</i> and O₃ distributions on the large scale and (ii) to focus on other improvements to reduce remaining uncertainties from processes related to NO_<i>x</i> chemistry in CTM

Sigma Coloring and Edge Deletions

A vertex coloring c : V(G) → N of a non-trivial graph G is called a sigma coloring if σ(u) is not equal to σ(v) for any pair of adjacent vertices u and v. Here, σ(x) denotes the sum of the colors assigned to vertices adjacent to x. The sigma chromatic number of G, denoted by σ(G), is defined as the fewest number of colors needed to construct a sigma coloring of G. In this paper, we consider the sigma chromatic number of graphs obtained by deleting one or more of its edges. In particular, we study the difference σ(G)−σ(G−e) in general as well as in restricted scenarios; here, G−e is the graph obtained by deleting an edge e from G. Furthermore, we study the sigma chromatic number of graphs obtained via multiple edge deletions in complete graphs by considering the complements of paths and cycles

Pressure-induced phase transition of Bi2Te3 into the bcc structure

The pressure-induced phase transition of bismuth telluride, Bi2Te3, has been studied by synchrotron x-ray diffraction measurements at room temperature using a diamond-anvil cell (DAC) with loading pressures up to 29.8 GPa. We found a high-pressure body-centered cubic (bcc) phase in Bi2Te3 at 25.2 GPa, which is denoted as phase IV, and this phase apperars above 14.5 GPa. Upon releasing the pressure from 29.8 GPa, the diffraction pattern changes with pressure hysteresis. The original rhombohedral phase is recovered at 2.43 GPa. The bcc structure can explain the phase IV peaks. We assumed that the structural model of phase IV is analogous to a substitutional binary alloy; the Bi and Te atoms are distributed in the bcc-lattice sites with space group Im-3m. The results of Rietveld analysis based on this model agree well with both the experimental data and calculated results. Therefore, the structure of phase IV in Bi2Te3 can be explained by a solid solution with a bcc lattice in the Bi-Te (60 atomic% tellurium) binary system.Comment: 12 pages, 5 figure

The sigma chromatic number of the Sierpinski gasket graphs and the Hanoi graphs

A vertex coloring c : V(G) → of a non-trivial connected graph G is called a sigma coloring if σ(u) ≠ σ(v) for any pair of adjacent vertices u and v. Here, σ(x) denotes the sum of the colors assigned to vertices adjacent to x. The sigma chromatic number of G, denoted by σ(G), is defined as the fewest number of colors needed to construct a sigma coloring of G. In this paper, we determine the sigma chromatic numbers of the Sierpiński gasket graphs and the Hanoi graphs. Moreover, we prove the uniqueness of the sigma coloring for Sierpiński gasket graphs