Transitions to Proton States in the 90-Zr(p,p') Reaction at 160 MeV

This work was supported by National Science Foundation Grant PHY 76-84033 and Indiana Universit

Excitation of Neutron, Proton and Neutron-Hole States in the (p,p') Reaction at 160 MeV and 96 MeV

This work was supported by National Science Foundation Grant PHY 76-84033 and Indiana Universit

Core Polarization Amplitudes for Single-Neutron-Hole Transitions Excited in the 207-Pb(p,p') Reaction at 135 MeV and 61 MeV

This work was supported by National Science Foundation Grants PHY 76-84033A01, PHY 78-22774, and Indiana Universit

Novel glassy behavior in a ferromagnetic p-spin model

Recent work has suggested the existence of glassy behavior in a ferromagnetic model with a four-spin interaction. Motivated by these findings, we have studied the dynamics of this model using Monte Carlo simulations with particular attention being paid to two-time quantities. We find that the system shares many features in common with glass forming liquids. In particular, the model exhibits: (i) a very long-lived metastable state, (ii) autocorrelation functions that show stretched exponential relaxation, (iii) a non-equilibrium timescale that appears to diverge at a well defined temperature, and (iv) low temperature aging behaviour characteristic of glasses.Comment: 6 pages, 5 figure

Operation of a hybrid modular multilevel converter during grid voltage unbalance

The recently proposed parallel hybrid modular multilevel converter is considered to be a low loss, low component count converter with soft switching capability of the ‘main’ H-bridge. The converter has similar advantages to other emerging modular multilevel converter circuits being considered for HVDC power transmission and can be made compact which is desirable for offshore application. However, during ac network unbalance the individual ‘chain-links’ exchange unequal amounts of power with the grid which requires appropriate remedial action. This paper presents research into the performance of the converter and proposes a suitable control method that enables the converter to operate during grid voltage unbalance. The proposed control concept involves the use of asymmetric third harmonic voltage generation in the ‘chain-links’ of the converter to redistribute the power exchanged between the individual ‘chain-links’ and the grid. Mathematical analysis and simulation modelling with results are presented to support the work described

Spin-Orbit Effects in the Excitation of Proton and Neutron States in the (p,p') Reaction at 160 MeV, 120 MeV, and 95 MeV

Supported by the National Science Foundation and Indiana Universit

Youth perceptions of how neighborhood physical environment and peers affect physical activity: a focus group study

Abstract Objective There is need for a youth-informed conceptualization of how environmental and social neighborhood contexts influence physical activity. We assessed youths’ perceptions of their neighborhood physical and peer environments as affecting physical activity. Methods Thirty-three students (20 girls; ages 12-14 years) participated in focus groups about the physical environment and peers within their neighborhoods, and their understanding of how they affect physical activity. Results Inductive analysis identified themes of access (e.g., to equipment); aesthetics; physical and social safety; peer proximity and behavior (e.g., bullying); adult support or interference; and adult boundary setting. Participants also identified interconnections among themes, such as traffic shaping parent boundary setting and, in turn, access to physical spaces and peers. Conclusions Young adolescents view neighborhoods in ways similar to and different from adults. Examining physical and social environments in tandem, while mindful of how adults shape and youth perceive these environments, may enhance understanding of youth physical activity behavior

Pair production of the heavy leptons in future high energy linear e^{+}e^{-} colliders

The littlest Higgs model with T-parity predicts the existence of the T-odd particles, which can only be produced in pair. We consider pair production of the T-odd leptons in future high energy linear $e^{+}e^{-}$ collider ($ILC$). Our numerical results show that, as long as the T-odd leptons are not too heavy, they can be copiously produced and their possible signals might be detected via the processes $e^{+}e^{-}\to \bar{L}_{i}L_{j}$ in future $ILC$ experiments.Comment: Discussions added, typos and references correcte

Temperature dependence of the breakdown of the quantum Hall effect studied by induced currents

Copyright © 2004 The American Physical SocietyWe have developed a model of the high-current breakdown of the integer quantum Hall effect, as measured in contactless experiments using a highly-sensitive torsion balance magnetometer. The model predicts that, for empirically “low-mobility” samples (μ<75 m2 V−1 s−1), the critical current for breakdown should decrease with, and have a linear dependence on, temperature. This prediction is verified experimentally with the addition of a low-temperature saturation of the critical current at a temperature that depends on both sample number density and filling factor. It is shown that this saturation is consistent with quasielastic inter-Landau-level scattering when the maximum electric field in the sample reaches a large enough value. In addition we show how this model can be extended to give qualitative agreement with experiments on high-mobility samples