• Attractive electromagnetic Casimir stress on a spherical dielectric shell 

      Graham, N.; Quandt, M.; Weigel, H. (Elsevier, 2013)
      Based on calculations involving an idealized boundary condition, it has long been assumed that the stress on a spherical conducting shell is repulsive. We use the more realistic case of a Drude dielectric to show that the ...
    • Chiral bands in 193Tl 

      Ndayishimye, J.; Lawrie, E. A.; Shirinda, O.; Easton, J. L.; Wyngaardt, S. M.; Bark, R. A.; Bvumbi, S. P.; Dinoko, T. R. S.; Jones, P.; Kheswa, N. Y.; Lawrie, J. J.; Majola, S. N. T.; Masiteng, P. L.; Negi, D.; Orce, J. N.; Papka, P.; Sharpey-Schafer, J. F.; Stankiewicz, M.; Wiedeking, M. (Jagiellonian University, 2017-03)
      Since the introduction of chirality in nuclei, the search for chiral candidates in different mass regions has been a hot topic for about two decades. At iThemba LABS, a new chiral symmetry region, the thallium isotopes with ...
    • A class of spatio-temporal and causal stochastic processes, with application to multiscaling and multifractality 

      Schmiegel, Schmiegel; Barndorff-Nielsen, Ole E.; Eggers, Hans C. (Academy of Science for South Africa, 2005)
      We present a general class of spatio-temporal stochastic processes describing the causal evolution of a positive-valued field in space and time. The field construction is based on independently scattered random measures ...
    • Classical and quantum filaments in the ground state of trapped dipolar Bose gases 

      Cinti, Fabio; Boninsegni, Massimo (American Physical Society, 2017)
      We study, by quantum Monte Carlo simulations, the ground state of a harmonically confined dipolar Bose gas with aligned dipole moments and with the inclusion of a repulsive two-body potential of varying range. Two different ...
    • Defect-induced supersolidity with soft-core bosons 

      Cinti, F.; Macri, T.; Lechner, W.; Pupillo, G.; Pohl, T. (Nature Publishing Group, 2014)
      More than 40 years ago, Andreev, Lifshitz and Chester suggested the possible existence of a peculiar solid phase of matter, the microscopic constituents of which can flow superfluidly without resistance due to the formation ...
    • Diffusions conditioned on occupation measures 

      Angeletti, Florian; Touchette, Hugo (AIP, 2016-02)
      A Markov process fluctuating away from its typical behavior can be represented in the long-time limit by another Markov process, called the effective or driven process, having the same stationary states as the original ...
    • Distorted-wave Born approximation study of the 11Li(p,t) 9Li reaction 

      Cowley, A. A. (IOP Publishing, 2016)
      The reaction 11Li(p,t) 9Li(gs) at an incident energy of 4 MeV is treated in terms of a simplistic distorted-wave Born approximation transfer. The halo neutrons involved in the reaction are treated as a di-neutron cluster ...
    • Duality constructions from quantum state manifolds 

      Kriel, J. N.; Van Zyl, H. J. R.; Scholtz, F. G. (Springer, 2015-11-20)
      The formalism of quantum state space geometry on manifolds of generalised coherent states is proposed as a natural setting for the construction of geometric dual descriptions of non-relativistic quantum systems. These state ...
    • Emerging translational variance : vacuum polarization energy of the 𝜙6 kink 

      Weigel, H. (Hindawi, 2017-07-30)
      We propose an efficient method to compute the vacuum polarization energy of static field configurations that do not allow decomposition into symmetric and antisymmetric channels in one space dimension. In particular, we ...
    • Entanglement-enhanced spreading of correlations 

      Kastner, Michael (IOP Publishing, 2015-12-17)
      Starting from a product initial state, equal-time correlations in nonrelativistic quantum lattice models propagate within a light cone-like causal region. The presence of entanglement in the initial state can modify this ...
    • Examination of evidence for collinear cluster tri-partition 

      Pyatkov, Yu. V.; Kamanin, D. V.; Alexandrov, A. A.; Alexandrova, I. A.; Goryainova, Z. I.; Malaza, V.; Mkaza, N.; Kuznetsova, E. A.; Strekalovsky, A. O.; Strekalovsky, O. V.; Zhuchko, V. E. (American Physical Society, 2017)
      Background: In a series of experiments at different time-of-flight spectrometers of heavy ions we have observed manifestations of a new at least ternary decay channel of low excited heavy nuclei. Due to specific features ...
    • Exchange-induced crystallization of soft-core bosons 

      Cinti, Fabio; Boninsegni, Massimo; Pohl, Thomas (Institute of Physics, 2014-03-28)
      We study the phase diagram of a two-dimensional assembly of bosons interacting via a soft-core repulsive pair potential of varying strength, and compare it to that of the equivalent system in which particles are regarded ...
    • Femtosecond laser diagnostics of thin films, surfaces and interfaces 

      Scheidt, T.; Rohwer, E. G.; Bergmann, H. M. V.; Stafast, H. (Academy of Science for South Africa, 2005)
      An overview is given of optical second harmonic generation (SHG) using femtosecond laser pulses to analyse technologically important crystalline materials. The principle of SHG is briefly explained and a typical experimental ...
    • Femtosecond pump probe spectroscopy for the study of energy transfer of light-harvesting complexes from extractions of spinach leaves 

      Ombinda-Lemboumba, S.; Du Plessis, A.; Sparrow, R. W.; Molukanele, P.; Botha, L. R.; Rohwer, E. G.; Steenkamp, C. M.; Van Rensburg, L. (Academy of Science of South Africa (ASSAf), 2009-10)
      Measurements of ultrafast transient processes, of temporal durations in the picosecond and femtosecond regime, are made possible by femtosecond pump probe transient absorption spectroscopy. Such an ultrafast pump probe ...
    • Galactic production of 138La : Impact of 138,139La statistical properties 

      Kheswa, B. V.; Wiedeking, M.; Giacoppo, F.; Goriely, S.; Guttormsen, M.; Larsen, A. C.; Bello Garrote, F. L.; Eriksen, T. K.; Gorgen, A.; Hagen, T. W.; Koehler, P. E.; Klintefjord, M.; Nyhus, H. T.; Papka, P.; Renstrom, T.; Rose, S.; Sahin, E.; Siem, S.; Tornyi, T. (Elsevier, 2015)
      The γ-ray strength functions and nuclear level densities of 138La and 139La have been measured below the neutron separation energies. These new data were used to calculate astrophysical Maxwellian-averaged (n, γ) cross-sections ...
    • Heavy baryons with strangeness in a soliton model 

      Blanckenberg, J. P.; Weigel, H. (Elsevier, 2015-09)
      We present results from a chiral soliton model calculation for the spectrum of baryons with a single heavy quark (charm or bottom) and non-zero strangeness. We treat the strange components within a three flavor collective ...
    • High-power excimer and CO2 TEA laser technology 

      Von Bergmann, H. M. (Academy of Science for South Africa, 2005)
      This article reviews the physical background and design of high-power excimer and CO2 TEA lasers, including a detailed discussion of electrode structures and pre-ionization, gas circulation and acoustic wave management as ...
    • High-resolution vacuum ultraviolet laser spectroscopy of molecules in a free supersonic jet : in search of rare CO isotopomers and CO-Ar van der Waals molecules 

      Steinmann, C. M.; Du Plessis, A.; Rohwer, E. G. (Academy of Science for South Africa, 2005)
      Tunable vacuum ultraviolet radiation (in the range 142.7-146.7 nm) from a novel laser source was used to probe the electronic excitation spectrum of cold carbon monoxide molecules in a supersonic noble gas jet. Rotationally ...
    • Higher-order interference and single-system postulates characterizing quantum theory 

      Barnum, Howard; Muller, Markus P.; Ududec, Cozmin (Institute of Physics, 2014-12-10)
      We present a new characterization of quantum theory in terms of simple physical principles that is different from previous ones in two important respects: first, it only refers to properties of single systems without any ...
    • An improved experimental setup for high-resolution vacuum ultraviolet laser spectroscopy 

      Steenkamp, C. M.; Du Plessis, A.; Rohwer, E. G. (Academy of Science for South Africa, 2005)
      The experimental setup for vacuum ultraviolet (VUV) laser spectroscopy at Stellenbosch University's Laser Research Institute, has been improved by the addition of a VUV monochromator. The VUV source has been characterized ...