Theoretical LSP detection rates for <Superscript>71</Superscript>Ga, <Superscript>73</Superscript>Ge,and <Superscript>127</Superscript>I dark-matter detectors

The low-energy structure of the dark-matter detector nuclei ⁷¹Ga, ⁷³Ge, and ¹²⁷I has been studied by using the microscopic quasiparticle-phonon model. The resulting ground states have been used to calculate theoretical predictions for detection rates of the lightest supersymmetric particle (LSP) in experiments studying elastic scattering of an LSP from an atomic nucleus. The highest rate, approximately 0.27 yr^?1kg^?1, among all the adopted SUSY parameters and renormalization schemes was provided by ¹²⁷I at the zero limit of the detector energy threshold.     

Adaptation and Enhancement of Generalized Polynomial Chaos for Industrial Applications

This contribution presents ideas, how to adapt stochastic elements to industrial applications and reduce the number of simulations in comparison to Monte Carlo. Especially when the mathematical model equations are not known and just an input/output interface is given. For this so called black box model which can be generated by many simulation tools the generalized polynomial chaos based on the idea of Wiener [1], and extended by Xiu and Karniadakis [2] is a suitable technique. One main advantage of this concept can be seen in the ability to produce functional representations of stochastic variability. This yields in a reduction of the simulation number compared to classical methods and can intensified by using a sparse grids approach [3]. Looking at industrial applications the concept can be applied to a huge amount of systems. For example, components including electronic drives, fuel injection valves, and mechanical parts. As an example of use, a simplified model of a DC drive with six uncertain parameters is taken into account. (© 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)     

Computational study of the perhalogenated methyl nitrates CX3ONO2, CX x Y3−x ONO2 (X,Y = F,Cl)

Ab initio and density functional theory methods are employed to study the structures, harmonic frequencies, energetics and thermodynamic properties of the perhalogenated methyl nitrates, CX₃ONO₂, CX _x Y_3?x ONO₂ (X, Y =?F, Cl), which may be formed as secondary reactive intermediates in the coupling of the halogenated methylperoxy radicals with NO. Reaction energies are computed with respect to CX₃O₂ +?NO, CX _x Y_3?x O₂ +?NO and CX₃O +?NO₂, CX _x Y_3?x O +?NO₂ radical pair decomposition species. The large heat of formation values calculated indicate the high stabilization achieved upon halogenation of the methyl radical, particularly for the fluorinated compounds. Thus, the halogenated methyl nitrates which appear in the oxidation chain of halomethanes can be thermally deactivated under suitable temperature and pressure conditions and act as reservoir compounds for the halogenated methylperoxy radicals, CX₃O₂, CX _x Y_3?x O₂ and NO, in the troposphere. The computational investigation also demonstrates the significant structural changes caused by the halogen electron withdrawing effect, compared with the methyl analogue, CH₃ONO₂.     

Upper limits for lepton-flavor violation from the exotic μ− ν e− conversion

The transition matrix elements for coherent and incoherent channels of the neutrinoless ^– e^– conversion are investigated. The results refer to the ²⁷Al nucleus which has recently been chosen as a target in the MECO experiment at Brookhaven aiming to search for -e conversion events with a sensitivity 10^-17. These results are compared to those obtained previously for ⁴⁸Ti and ²⁰⁸Pb targets. We focus on the contributions to the branching ratio e^– originating from scalar, vector and axial vector interactions resulting in conventional extentions of the standard model and minimal supersymmetric models with and without -parity violation. With our calculations we extract very severe constraints for the flavor violation parameters.     

Direct observation of magnetic ordering in the (CH3NH2)K3C60 fulleride

The zero-field muon-spin-relaxation (ZF-micro(+)SR) technique provides direct observation of the development of antiferromagnetic long range order in the hyperexpanded methylaminated fulleride salt, (CH(3)NH(2))K(3)C(60) below T(N) approximately 10 K-coherent ordering of the electronic magnetic moments leads to a local field of approximately 25 G at the muon site at 1.2 K.     

Theoretical study of the microhydration of 1-chloro and 2-chloro ethanol as a clue for their relative propensity toward dehalogenation

This work reports a computational analysis of hydrogen-bonded clusters of mono-, di-, tri-, and tetrahydrates of the chlorohydrins CH₃CHClOH (1ClEtOH) and CH₂ClCH₂OH (2ClEtOH). The goal of the study is to assess the role of the water solvent into the facilitation of the initial step for dehalogenation of these compounds, a process of interest in several contexts. Molecular orbital methods (MP2), density functional methods (B3LYP, M06, and ωB97X-D), and composite model chemistries (CBS-QB3, G4) were employed to investigate the structure, electronic distribution, and hydrogen-bonded structure of seven monohydrates, six dihydrates, five trihydrates, and five tetrahydrates of both species. Standard reaction enthalpy and standard Gibbs free reaction energy () were computed for all aggregates with respect to n independent water molecules and with respect to the dimer, trimer, and tetramer of water, respectively, in order to evaluate stability and hydrogen bonding network. The influence of the water chains on the length and vibrational frequencies, especially of the C Cl and O H bonds, was evaluated. Hydrogen bonding in the complexes is discussed at length.     

A theoretical study of conformational properties of dendritic block copolymers of first generation

Conformational properties of a dendritic block copolymer of the first generation are studied by means of an analytic calculation and dimensionality techniques. The polymer can have different functionalities and branch lengths in the interior region and the exterior shell. Three parameters are included in order to describe the intensity of the interactions between the same or different monomeric units. Based on the average end to end distances of the branches effective angles are defined in order to study how the microscopic parameters control the position and activity of the end groups, but also the hollowness in the internal region and the tweezing ability of the external shell of the macromolecule.     

Theoretical enthalpies of formation and structural characterisation of halogenated nitromethanes and isomeric halomethyl nitrites

The structural, energetic, and thermochemical properties of a number of halogenated nitromethanes, CH _n X_3?n NO₂, and the isomeric nitrites, CH _n X_3?n ONO, are investigated, using theoretical ab initio and density functional theory (DFT) electronic structure methods. Analysis of the results and comparison with the maternal species, nitromethane, CH₃NO₂, and methyl nitrite, CH₃ONO, reveal strong dependence of the molecular properties on the halogen induction effect. Opposite trends are obtained in the C??N and C??O bond dissociation energies (BDE) upon halogenation and higher stabilities are calculated for the trans-nitrite isomers, in contrast with the plain alkyl families where the nitroalkanes are the most stable species. Formation enthalpies, ??H _f ^? , at 298 K are calculated for all halogenated isomers.     

Inelastic neutrino scattering off stable even-even Mo isotopes at low and intermediate energies

Inelastic neutrino scattering cross sections for the even-even Mo isotopes (contents of the MOON detector at Japan), at low and intermediate electron neutrino energies (?_i≤100 MeV), are calculated. MOON is a next-generation double beta and neutrino-less double-beta-decay experiment which is also a promising facility for low-energy neutrino detection. The nuclear wave functions required in this work have been constructed in the context of the quasi-particle random phase approximation (QRPA) and the results presented refer to , , , and isotopes.