Calculations of giant magnetoresistance in Fe/Cr trilayers using layer potentials determined from {\it ab-initio} methods

The ab initio full-potential linearized augmented plane-wave method explicitly designed for the slab geometry was employed to elucidate the physical origin of the layer potentials for the trilayers nFe/3Cr/nFe(001), where n is the number of Fe monolayers. The thickness of the transition-metal ferromagnet has been ranged from $n=1$ up to n=8 while the spacer thickness was fixed to 3 monolayers. The calculated potentials were inserted in the Fuchs-Sondheimer formalism in order to calculate the giant magnetoresistance (GMR) ratio. The predicted GMR ratio was compared with the experiment and the oscillatory behavior of the GMR as a function of the ferromagnetic layer thickness was discussed in the context of the layer potentials. The reported results confirm that the interface monolayers play a dominant role in the intrinsic GMR.Comment: 17 pages, 7 figures, 3 tables. accepted in J. Phys.: Cond. Matte

Characterization of the autotrophic component in periphyton upon \u3ci\u3eTypha angustifolia\u3c/i\u3e detritus in a freshwater wetland

The autotrophic component of periphyton on Typha angustifolia detritus was characterized in a freshwater wetland during a single growing season. 58 genera of algae and cyanobacteria, representing six divisions, were observed throughout the study period. Although the combined algae-cyanobacteria density from within and outside the Typha stands were significantly affected by both sample date and the combination of date and location, no significant differences occurred in biovolume. Similarly, no clear evidence of successional patterns was observed. Although few significant interactions were observed, Typha detritus provided a substratum for vast numbers and biomass of periphyton. A combined density for the observed taxa within the Typha stand averaged 134,588 cells cm-2, while the density outside the stand averaged 108,853 cells cm-2. The average total biovolume for the taxa within the Typha stand was 245 x 106 ± 23 x 106 and 136 x 103 ± 314 x 106 um3 cm-2 outside

Selfconsistent calculations of fission barriers in the Fm region

The fission barriers of the nuclei 254Fm, 256Fm, 258Fm, 258No and 260Rf are investigated in a fully microscopic way up to the scission point. The analysis is based on the constrained Hartree-Fock-Bogoliubov theory and Gogny's D1S force. The quadrupole, octupole and hexadecapole moments as well as the number of nucleons in the neck region are used as constraints. Two fission paths, corresponding to the bimodal fission, are found. The decrease with isotope mass of the half-life times of heavy Fm isotopes is also explained.Comment: 29 pages in LaTeX including 14 figure

Misfits in Skyrme-Hartree-Fock

We address very briefly five critical points in the context of the Skyrme-Hartree-Fock (SHF) scheme: 1) the impossibility to consider it as an interaction, 2) a possible inconsistency of correlation corrections as, e.g., the center-of-mass correction, 3) problems to describe the giant dipole resonance (GDR) simultaneously in light and heavy nuclei, 4) deficiencies in the extrapolation of binding energies to super-heavy elements (SHE), and 5) a yet inappropriate trend in fission life-times when going to the heaviest SHE. While the first two points have more a formal bias, the other three points have practical implications and wait for solution.Comment: 9 pages, 4 figure

Fission modes of mercury isotopes

Background: Recent experiments on beta-delayed fission in the mercury-lead region and the discovery of asym- metric fission in 180 Hg [1] have stimulated theoretical interest in the mechanism of fission in heavy nuclei. Purpose: We study fission modes and fusion valleys in 180 Hg and 198 Hg to reveal the role of shell effects in pre-scission region and explain the experimentally observed fragment mass asymmetry and its variation with A. Methods: We use the self-consistent nuclear density functional theory employing Skyrme and Gogny energy density functionals. Results: The potential energy surfaces in multi-dimensional space of collective coordinates, including elongation, triaxiality, reflection-asymmetry, and necking, are calculated for 180 Hg and 198 Hg. The asymmetric fission valleys - well separated from fusion valleys associated with nearly spherical fragments - are found in in both cases. The density distributions at scission configurations are studied and related to the experimentally observed mass splits. Conclusions: The energy density functionals SkM\ast and D1S give a very consistent description of the fission process in 180 Hg and 198 Hg. We predict a transition from asymmetric fission in 180 Hg towards more symmetric distribution of fission fragments in 198 Hg. For 180 Hg, both models yield 100 Ru/80 Kr as the most probable split. For 198 Hg, the most likely split is 108 Ru/90 Kr in HFB-D1S and 110 Ru/88 Kr in HFB-SkM\ast.Comment: 6 pages, 5 figures, to be published in Physical Review

The Beam Conditions Monitor of the LHCb Experiment

The LHCb experiment at the European Organization for Nuclear Research (CERN) is dedicated to precision measurements of CP violation and rare decays of B hadrons. Its most sensitive components are protected by means of a Beam Conditions Monitor (BCM), based on polycrystalline CVD diamond sensors. Its configuration, operation and decision logics to issue or remove the beam permit signal for the Large Hadron Collider (LHC) are described in this paper.Comment: Index Terms: Accelerator measurement systems, CVD, Diamond, Radiation detector

Analysis of bulk and surface contributions in the neutron skin of nuclei

The neutron skin thickness of nuclei is a sensitive probe of the nuclear symmetry energy having multiple implications for nuclear and astrophysical studies. However, precision measurements of this observable are difficult. The analysis of the experimental data may imply some assumptions about the bulk or surface nature of the formation of the neutron skin. Here, we study the bulk or surface character of neutron skins of nuclei following from calculations with Gogny, Skyrme, and covariant nuclear mean-field interactions. These interactions are successful in describing nuclear charge radii and binding energies but predict different values for neutron skins. We perform the study by fitting two-parameter Fermi distributions to the calculated self-consistent neutron and proton densities. We note that the equivalent sharp radius is a more suitable reference quantity than the half-density radius parameter of the Fermi distributions to discern between the bulk and surface contributions in neutron skins. We present calculations for nuclei in the stability valley and for the isotopic chains of Sn and Pb.Comment: 13 pages, 9 figure

Analysis of bulk and surface contributions in the neutron skin of nuclei

The neutron skin thickness of nuclei is a sensitive probe of the nuclear symmetry energy having multiple implications for nuclear and astrophysical studies. However, precision measurements of this observable are difficult. The analysis of the experimental data may imply some assumptions about the bulk or surface nature of the formation of the neutron skin. Here, we study the bulk or surface character of neutron skins of nuclei following from calculations with Gogny, Skyrme, and covariant nuclear mean-field interactions. These interactions are successful in describing nuclear charge radii and binding energies but predict different values for neutron skins. We perform the study by fitting two-parameter Fermi distributions to the calculated self-consistent neutron and proton densities. We note that the equivalent sharp radius is a more suitable reference quantity than the half-density radius parameter of the Fermi distributions to discern between the bulk and surface contributions in neutron skins. We present calculations for nuclei in the stability valley and for the isotopic chains of Sn and Pb.Comment: 13 pages, 9 figure

Hubungan Persepsi Mutu Pelayanan dengan Tingkat Kepuasan Pasien Puskesmas Perumnas di Kota Kendari Tahun 2016

Berkembangnya jenis pelayanan kesehatan terutama di puskesmas membuat mutu pelayanan kesehatan di puskesmas mudah terabaikan.Penelitian ini bertujuan untuk melihat korelasiantara persepsi mutu pelayanan administrasi, dokter, perawat, obat dan kelengkapan sarana dengantingkat kepuasan pasien puskesmas Perumnas. Penelitian ini adalah penelitian observasional analitikdengan metode survey dan pendekatan crossectional. Penelitian dilaksanakan pada bulan maret2016 di puskesmas Perumnas. Populasi dalam penelitian ini adalah 14.553 orang dengan besarsampel 100 orang. Analisis data menggunakan dispersi data, uji korelasi spearman dan analisis faktordengan metode varimax. Hasil penelitian menunjukkan bahwa terdapat korelasi yang bermaknaantara persepsi mutu pelayanan administrasi, dokter, perawat, obat dan kelengkapan sarana dengantingkat kepuasan pasien (p0,9,transformation matrix 0,771> 0,5) dan faktor kedua yaitu persepsi mutu pelayanan obat dankelengkapan sarana (rotated component matriks> 0,8, transformation matrix 0,637> 0,5),dimanafaktor pertama dapat menjelaskan faktor sebesar 95%. Terdapat korelasi yang positif antara keduafaktor dengan kepuasan pasien dengan kekuatan korelasi yang kuat (>0,5), dimana faktor pertama(persepsi pelayanan dokter dan perawat) memiliki kekuatan korelasi yang paling besar (0,70).Disarankan terutama bagi puskesmas untuk membenahi pelayanan yang diberikan kepada pasienterutama pelayanan dokter dan perawat