11,092 research outputs found

    Shell model description of Ge isotopes

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    A shell model study of the low energy region of the spectra in Ge isotopes for 38N5038\leq N\leq 50 is presented, analyzing the excitation energies, quadrupole moments, B(E2)B(E2) values and occupation numbers. The theoretical results have been compared with the available experimental data. The shell model calculations have been performed employing three different effective interactions and valence spaces.We have used two effective shell model interactions, JUN45 and jj44b, for the valence space f5/2pg9/2f_{5/2} \, p \,g_{9/2} without truncation. To include the proton subshell f7/2f_{7/2} in valence space we have employed the fpgfpg effective interaction due to Sorlin {\it et al.}, with 48^{48}Ca as a core and a truncation in the number of excited particles.Comment: 10 pages, 10 figures, Proc. of the XXXV Nuclear Physics Symposium, January 3-6 2012, Cocoyoc, Morelos, Mexico. IOP Journal of Physics: Conference Series (in press

    Magnetoelectric Effects on Composite Nano Granular Fe/TiO2δFe/TiO_{2-\delta} Films

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    Employing a new experimental technique to measure magnetoelectric response functions, we have measured the magnetoelectric effect in composite films of nano granular metallic iron in anatase titanium dioxide at temperatures below 50 K. A magnetoelectric resistance is defined as the ratio of a transverse voltage to bias current as a function of the magnetic field. In contrast to the anomalous Hall resistance measured above 50 K, the magnetoelectic resistance below 50 K is significantly larger and exhibits an even symmetry with respect to magnetic field reversal HHH\to -H. The measurement technique required attached electrodes in the plane of the film composite in order to measure voltage as a function of bias current and external magnetic field. To our knowledge, the composite films are unique in terms of showing magnetoelectric effects at low temperatures, << 50 K, and anomalous Hall effects at high temperatures, >> 50 K.Comment: ReVTeX, 2 figures, 3 page

    Soft gluon radiation and energy dependence of total hadronic cross-sections

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    An impact parameter representation for soft gluon radiation is applied to obtain both the initial decrease of the total cross-section (σtot\sigma_{tot}) for proton-proton collisions as well as the later rise of σtot\sigma_{tot} with energy for both pppp and ppˉp\bar{p}. The non-perturbative soft part of the eikonal includes only limited low energy gluon emission and leads to the initial decrease in the proton-proton cross- section. On the other hand, the rapid rise in the hard, perturbative jet part of the eikonal is tamed into the experimentally observed mild increase by soft gluon radiation whose maximum energy rises slowly with energy.Comment: 30 pages, 6 figures. Version accepted for publication in Physical Review D. Additional section with explanatory material added making the paper more self contained and two figures changed to have a complete summary of the available accelerator dat

    Production of Like Sign Di-Leptons in p-p Collisions Through Composite Majorana Neutrinos

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    The production of Like-Sign-Di-leptons (LSD), in the high energy lepton number violating (ΔL=+2\Delta L = +2) reaction, p p --> 2jets + l+l+ (l=e,\mu,\tau) of interest for the experiments to be performed at the forthcoming Large Hadron Collider (LHC), is investigated in detail, taking up a composite model scenario in which the exchanged virtual composite neutrino is assumed to be a Majorana particle that couples to the light leptons via the SU(2)×U(1)SU(2)\times U(1) gauge bosons through a magnetic type coupling (σμν\sigma_{\mu\nu}). An helicity projection method is used to evaluate exactly the tree-level amplitudes of the contributing parton subprocesses (242\to 4), which allows to take into account all exchange diagrams and occurring interferences. Numerical estimates of the corresponding signal cross-section that implement kinematical cuts needed to suppress the Standard Model background, are presented which show that in some regions of the parameter space the total number of LSD events is well above the background. Assuming non-observation of the LSD signal it is found that LHC would exclude a composite Majorana neutrino up to 850 GeV (if one requires 10 events for discovery). The sensitivity of LHC experiments to the parameter space is then compared to that of the next generation of neutrinoless double beta decay (ββ0ν\beta\beta_{0\nu}) experiment, GENIUS, and it is shown that they will provide constraints of the same order of magnitude and will play a complementary role.Comment: Revtex style, 31 pages, 8 postscript figures. Few typos correcte

    Collaborative Layer-wise Discriminative Learning in Deep Neural Networks

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    Intermediate features at different layers of a deep neural network are known to be discriminative for visual patterns of different complexities. However, most existing works ignore such cross-layer heterogeneities when classifying samples of different complexities. For example, if a training sample has already been correctly classified at a specific layer with high confidence, we argue that it is unnecessary to enforce rest layers to classify this sample correctly and a better strategy is to encourage those layers to focus on other samples. In this paper, we propose a layer-wise discriminative learning method to enhance the discriminative capability of a deep network by allowing its layers to work collaboratively for classification. Towards this target, we introduce multiple classifiers on top of multiple layers. Each classifier not only tries to correctly classify the features from its input layer, but also coordinates with other classifiers to jointly maximize the final classification performance. Guided by the other companion classifiers, each classifier learns to concentrate on certain training examples and boosts the overall performance. Allowing for end-to-end training, our method can be conveniently embedded into state-of-the-art deep networks. Experiments with multiple popular deep networks, including Network in Network, GoogLeNet and VGGNet, on scale-various object classification benchmarks, including CIFAR100, MNIST and ImageNet, and scene classification benchmarks, including MIT67, SUN397 and Places205, demonstrate the effectiveness of our method. In addition, we also analyze the relationship between the proposed method and classical conditional random fields models.Comment: To appear in ECCV 2016. Maybe subject to minor changes before camera-ready versio

    Cloning and characterization of cDNA encoding xyloglucan endotransglucosylase in Pennisetum glaucum L.

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    Biomass production in plant is directly related to the amount of intercepted solar radiation by the canopy and available water to the plant. Growth and development of leaves, especially under drought condition, is therefore major determinant of crop productivity. Xyloglucan endotransglucosylase (XET) plays important role in growth and development of plants. XETs are a family of enzymes that mediate construction and restructuring of xyloglucan cross-links, thereby controlling the mechanical properties of cell wall. We cloned complete cDNA of an XET from pearl millet (Pennisetum glaucum L.) and characterized it using in silico comparative genomics and activity assays. The cloned cDNA was 1266 bp in length, encoding a protein with 291 amino acids having signal peptide targeting it to the cell wall. The protein showed xyloglucan endotransglucosylase activity but no hydrolytic activity, therefore, named as PgXET1 as per the convention. The comparative genomics revealed that the functional sites of the enzyme (XET) were highly conserved. Evolutionary studies using phylogenetic tree indicated its grouping with XETs from maize (with &gt;95% bootstrap support), barley, rice, etc. This is the first report on cloning and characterization of an XET (PgXET1) from pearl millet, an important dual-purpose crop.Key words: Xyloglucan endotransglucosylase, Pennisetum glaucum, pearl millet, primary cell wall, cell expansion, drought tolerance

    Neutrinoless Double β\beta Decay with Composite Neutrinos

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    We study in detail the contribution of heavy composite Majorana neutrinos to neutrino-less double beta decay. Our analysis confirms the result of a previous estimate by two of the authors. Excited neutrinos couple to the electroweak gauge bosons through a magnetic type effective Lagrangian. The relevant nuclear matrix element is related to matrix elements available in the literature and current bounds on the half-life of neutrino-less double beta decay are converted into bounds on the compositeness scale and/or the heavy neutrino mass. Our bounds are of the same order of magnitude as those available from accelerator experiments

    Interpolation function of the genocchi type polynomials

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    The main purpose of this paper is to construct not only generating functions of the new approach Genocchi type numbers and polynomials but also interpolation function of these numbers and polynomials which are related to a, b, c arbitrary positive real parameters. We prove multiplication theorem of these polynomials. Furthermore, we give some identities and applications associated with these numbers, polynomials and their interpolation functions.Comment: 14 page
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