Systematic limits on sin^2{2theta_{13}} in neutrino oscillation experiments with multi-reactors

Sensitivities to sin^2{2theta_{13}} without statistical errors (``systematic limit'') are investigated in neutrino oscillation experiments with multiple reactors. Using an analytical approach, we show that the systematic limit on sin^2{2theta_{13}} is dominated by the uncorrelated systematic error sigma_u of the detector. Even in an experiment with multi-detectors and multi-reactors, it turns out that most of the systematic errors including the one due to the nature of multiple sources is canceled as in the case with a single reactor plus two detectors, if the near detectors are placed suitably. The case of the KASKA plan (7 reactors and 3 detectors) is investigated in detail, and it is explicitly shown that it does not suffer from the extra uncertainty due to multiple reactors.Comment: 26 pages, 10 eps-files, revtex

Efficient solar light harvesting device based on multilayer photonic crystal films

We fabricate, characterize and calculate photonic-colloidal crystals. We propose to use wave guiding properties of photonic crystal films [1] to concentrate large amount of sunlight onto a small area of solar photovoltaic (PV) cells

Relativistic many-body calculation of low-energy dielectronic resonances in Be-like carbon

We apply relativistic configuration-interaction method coupled with many-body perturbation theory (CI+MBPT) to describe low-energy dielectronic recombination. We combine the CI+MBPT approach with the complex rotation method (CRM) and compute the dielectronic recombination spectrum for Li-like carbon recombining into Be-like carbon. We demonstrate the utility and evaluate the accuracy of this newly-developed CI+MBPT+CRM approach by comparing our results with the results of the previous high-precision study of the CIII system [Mannervik et al., Phys. Rev. Lett. 81, 313 (1998)].Comment: 6 pages, 1 figure; v2,v3: fixed reference

Methods For Evaluation Of The Education Quality In Higher Education Institutions

The article aims to disclose the essence of the “education quality” concept, to study the international approaches and concepts of the higher education quality evaluation, to analyze specific methods and tools within one of the approaches. Establishing education quality assessment necessitates choosing the teaching personnel of higher educational institution, as well as a target group of students and independent experts in the field of organization of the educational process, on a distance basis particularly. Monitoring requires using such methods as interviews, surveys, questionnaires, and similar. The results were processed according to the authors’ algorithm allowing to calculate the quality of education. The authors’ interpretation of the concept of “education quality” is proposed. Given the insufficient study of the topic of distance education in the domestic scientific discourse, authors’ attention to this problem is an important contribution to study of the issue of distance education. The methods used to evaluate the education quality in higher education institutions at the international level are an integral element in the development of the educational space, although they cause certain controversy and criticism. The authors advise to select the methods for evaluating the educational process quality with account of the specific evaluation stage and purpose

Magneto-infrared modes in InAs-AlSb-GaSb coupled quantum wells

We have studied a series of InAs/GaSb coupled quantum wells using magneto-infrared spectroscopy for high magnetic fields up to 33T within temperatures ranging from 4K to 45K in both Faraday and tilted field geometries. This type of coupled quantum wells consists of an electron layer in the InAs quantum well and a hole layer in the GaSb quantum well, forming the so-called two dimensional electron-hole bilayer system. Unlike the samples studied in the past, the hybridization of the electron and hole subbands in our samples is largely reduced by having narrower wells and an AlSb barrier layer interposed between the InAs and the GaSb quantum wells, rendering them weakly hybridized. Previous studies have revealed multiple absorption modes near the electron cyclotron resonance of the InAs layer in moderately and strongly hybridized samples, while only a single absorption mode was observed in the weakly hybridized samples. We have observed a pair of absorption modes occurring only at magnetic fields higher than 14T, which exhibited several interesting phenomena. Among which we found two unique types of behavior that distinguishes this work from the ones reported in the literature. This pair of modes is very robust against rising thermal excitations and increasing magnetic fields alligned parallel to the heterostructures. While the previous results were aptly explained by the antilevel crossing gap due to the hybridization of the electron and hole wavefunctions, i.e. conduction-valence Landau level mixing, the unique features reported in this paper cannot be explained within the same concept. The unusual properties found in this study and their connection to the known models for InAs/GaSb heterostructures will be disccused; in addition, several alternative ideas will be proposed in this paper and it appears that a spontaneous phase separation can account for most of the observed features

Basis set calculations of heavy atoms

Most modern calculations of many-electron atoms use basis sets of atomic orbitals. An accurate account for the electronic correlations in heavy atoms is very difficult computational problem and optimization of the basis sets can reduce computational costs and increase final accuracy. Here we suggest a simple differential ansatz to form virtual orbitals from the Dirac-Fock orbitals of the core and valence electrons. We use basis sets with such orbitals to calculate different properties in Cs including hyperfine structure constants and QED corrections to the valence energies and to the E1 transition amplitudes

Determining Neutrino Mass Hierarchy by Precision Measurements in Electron and Muon Neutrino Disappearance Experiments

Recently a new method for determining the neutrino mass hierarchy by comparing the effective values of the atmospheric \Delta m^2 measured in the electron neutrino disappearance channel, \Delta m^2(ee), with the one measured in the muon neutrino disappearance channel, \Delta m^2(\mu \mu), was proposed. If \Delta m^2(ee) is larger (smaller) than \Delta m^2(\mu \mu) the hierarchy is of the normal (inverted) type. We re-examine this proposition in the light of two very high precision measurements: \Delta m^2(\mu \mu) that may be accomplished by the phase II of the Tokai-to-Kamioka (T2K) experiment, for example, and \Delta m^2(ee) that can be envisaged using the novel Mossbauer enhanced resonant \bar\nu_e absorption technique. Under optimistic assumptions for the systematic uncertainties of both measurements, we estimate the parameter region of (\theta_13, \delta) in which the mass hierarchy can be determined. If \theta_13 is relatively large, sin^2 2\theta_13 \gsim 0.05, and both of \Delta m^2(ee) and \Delta m^2(\mu \mu) can be measured with the precision of \sim 0.5 % it is possible to determine the neutrino mass hierarchy at > 95% CL for 0.3 \pi \lsim \delta \lsim 1.7 \pi for the current best fit values of all the other oscillation parameters.Comment: 12 pages, 6 postscript figure