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The steady-state operation of high-performance plasmas in the Large Helical Device (LHD) has progressed since the 2010 IAEA Conference in Korea by means of a newly installed ion cyclotron heating (ICH) antenna (HAS antenna) and an improved electron cyclotron heating (ECH) system. The HAS antenna can control the launched parallel wave number and heat the core plasma efficiently in the case of dipole mode operation. Understanding of the physics and technology of wave heating, particle and heat flow balances, and plasma-wall interactions in LHD has also improved. The heating power of steady-state ICH and ECH exceeded 1MWand 500kW, respectively, and a higher density helium plasma with minority hydrogen ions was maintained using the HAS antenna and new 77 GHz gyrotrons. As a result, plasma performance improved, e.g. electron temperature of more than 2 keV at a density of more than 2 × 1019 m-3became possible for more than 1 min. Heat flow balance and particle flux balance of steady-state operation were evaluated. Particle balance analysis indicated that externally fed helium and hydrogen particles were mainly absorbed by the chamber wall and divertor plates, even after the 54 min operation. [ABSTRACT FROM AUTHOR]

We have installed a shift register system of extensive air show (EAS) particles in a compact EAS array built on the rooftop of the Faculty of Engineering building in the campus of Okayama University of Science and being operated since April 2006 as part of Large Area Air Shower (LAAS) experiments , in order to register each arrival time of EAS particles within 5 µs. Detector simulations based on the database obtained from one of the standard cosmic ray propagation simulator in the atmosphere (AIRES) have also been carried out and the procedures to estimate the primary cosmic ray energy from the Linsley's method have been developed and examined. Applying Linsley's method to the EAS data obtained by our EAS arrays and the simulation results, we derived the energy spectrum from 1016 eV to 1019.5 eV Consequently, we obtained the power-law index of -3.2 (+0.46 -0.8) in the primary energy range of 1016 eV to 1018.5 eV, and obtained that a change around 1018 eV appeared if not taking account of the zenith angle distribution of primary cosmic rays. We compared the obtained energy spectrum with other experimental data above 1016 eV energies, and showed the two components of power-law energy spectra well described our data. We also showed the improvement of energy resolution by applying the restriction of zenith angle of primary cosmic rays in our simulation results, as well as the potential of the Linsley's method with a compact EAS array. [ABSTRACT FROM AUTHOR]

Proposed a new method which is suitable for systematic calculations in few-body systems, we call it the Jacobi-coordinate-basis antisymmetrized molecular dynamics (JAMD). We show good abilities of the method by demonstrating some examples in atoms, molecules, nuclei, and baryons systems. [ABSTRACT FROM AUTHOR]

A wave detector, a newly designed magnetic probe, is installed in the large helical device (LHD). This wave detector is a 100-turn loop coil with electrostatic shield. Comparing a one-loop coil to this detector, this detector has roughly constant power coupling in the lower frequency range of 40 MHz, and it can easily detect magnetic wave in the frequency of a few megahertz. During high-harmonic fast wave heating, lower frequency waves (<10 MHz) were observed in the LHD for the first time, and for the power density threshold of lower frequency wave excitation (7.5 MHz) the power density of excited pumped wave (38.47 MHz) was approximately -46 dBm/Hz. These lower frequencies are kept constant for electron density and high energy particle distribution, and these lower frequency waves seem to be ion cyclotron waves caused by nonlinear wave-particle interaction, for example, parametric decay instability. [ABSTRACT FROM AUTHOR]

Abstract: Low-resistivity n-type ZnO thin films were grown by atomic layer deposition (ALD) using diethylzinc (DEZ) and H2O as Zn and O precursors. ZnO thin films were grown on -plane sapphire (- Al2O3) substrates at 300 ∘C. For undoped ZnO thin films, it was found that the intensity of ZnO () reflection peak increased and the electron concentration increased from 6.8×1018 to 1.1×1020 cm−3 with the increase of DEZ flow rate, which indicates the increase of O vacancies () and/or Zn interstitials (Zn i ). Ga-doping was performed under Zn-rich growth conditions using triethylgallium (TEG) as Ga precursor. The resistivity of 8.0×10−4 Ω cm was achieved at the TEG flow rate of 0.24 μmol/min. [Copyright &y& Elsevier]

We study the bound-nucleon sigma term and the quark condensate in nuclear matter. In the quark-meson coupling (QMC) model the nuclear correction to the sigma term is small and negative, i.e., it decelerates the decrease of the quark condensate in nuclear matter. However, the quark condensate in nuclear matter is controlled primarily by the scalar-isoscalar σ field. Compared to the leading term, it moderates the decrease more than that of the nuclear sigma term alone at densities around and larger than the normal nuclear-matter density. [ABSTRACT FROM AUTHOR]

The neoclassical magnetohydrodynamic equilibrium of reversed-field pinch (RFP) is self-consistently solved considering the self-induced plasma current I[lowercase_phi_synonym]SI in a reactor relevant parameter regime. The current I[lowercase_phi_synonym]SI consists of bootstrap currents due to α particles as well as the bulk plasma, where the conventional neoclassical transport theory is applied without considering the finite banana-width effect, Pfirsch–Schluter current, and diamagnetic current. The neoclassical effect enhances I[lowercase_phi_synonym]SI in a low-aspect-ratio RFP (aspect ratio A=2), when β is high. An I[lowercase_phi_synonym]SI as high as 94.4% of the plasma current in the equilibrium with ellipticity κ=1.4 and triangularity δ=0.4 is obtained with a flat pressure profile, which provides a toroidal β of βt=63% (volume-averaged β, 〈β〉=66%) stable against both the ideal kink mode and Mercier mode. This dominant self-induced current makes the steady-state approach feasible. Its hollow current profile gives a strong magnetic shear and a high-stability β. [ABSTRACT FROM AUTHOR]

Abstract: Effect of bound nucleon internal structure change on nuclear structure functions is investigated based on local quark–hadron duality. The bound nucleon structure functions calculated for charged-lepton and (anti)neutrino scattering are all enhanced in symmetric nuclear matter at large Bjorken-x () relative to those in a free nucleon. This implies that a part of the enhancement observed in the nuclear structure function (in the resonance region) at large Bjorken-x (the EMC effect) is due to the effect of the bound nucleon internal structure change. However, the x dependence for the charged-lepton and (anti)neutrino scattering is different. The former (latter) is enhanced (quenched) in the region () due to the difference of the contribution from axial vector form factor. Because of these differences charge symmetry breaking in parton distributions will be enhanced in nuclei. [Copyright &y& Elsevier]

A new high-spin isomer in 150Dy has been observed at an excitation energy of 10.3 MeV by combining the inverse-kinematic reaction induced by a pulsed beam of 152Xe and the γ-ray recoil-shadow technique. The half-life of this isomeric state has been determined to be T⅛ = 1.6±0.6 ns using the conventional centroid-shift method with the 141Pr(16O, p6n)150Dy reaction at 165 MeV. The mechanism producing high-spin isomers in N = 83,84 isotones is qualitatively discussed in terms of the difference of the neutron particle-hole configuration between the high-spin isomer and the lower-lying state. [ABSTRACT FROM AUTHOR]

The authors observe relaxation dynamics of spin-polarized electrons excited at a higher-energy spin-split subband in a diluted magnetic semiconductor quantum well by means of pump-probe absorption spectroscopy. Time dependences of the circularly polarized saturated absorbance directly show the relaxation of spin-polarized electrons, which is inaccessible by photoluminescence. The probe-energy dependence of the relaxation time is obtained ranging from 2 to 100 ps at 2.5 T within the absorption band. This dependence is systematically explained by both the intraband energy relaxation of the spin-polarized electrons and the subsequent electron-spin relaxation that is modified by effects of the exciton localization. [ABSTRACT FROM AUTHOR]

Reaction cross sections for 11Be and 8B on proton targets at 40A - 120A MeV have been measured by the transmission method. With these data, we can discuss the proton- and neutron- density distributions at the nuclear surface independently in principle using the Glauber theory. Our experimental results support that the constituent of halo in 11Be is neutron dominantly and that of 8B is proton dominantly. [ABSTRACT FROM AUTHOR]

Abstract: Using the volume coupling version of the cloudy bag model, the quark–meson coupling model is extended to study the role of pion field and the properties of nuclear matter. The extended model includes the effect of gluon exchange as well as the pion-cloud effect, and provides a good description of the nuclear matter properties. The relationship between the extended model and the EFT approach to nuclear matter is also discussed. [Copyright &y& Elsevier]