16,466 research outputs found
Odd Parity and Line Nodes in Heavy Fermion Superconductors
Group theory arguments have demonstrated that a general odd parity order
parameter cannot have line nodes in the presence of spin-orbit coupling. In
this paper, it is shown that these arguments do not hold on the
zone face of a hexagonal close packed lattice. In particular, three of the six
odd parity representations vanish identically on this face. This has potential
relevance to the heavy fermion superconductor .Comment: 5 pages, revte
Assessment of semicircular canal function. Part 1 - Measurements of subjective effects produced by triangular waveforms of angular velocity
Nystagmus and sensation of rotation from semicircular canal stimulation by triangular waveforms of angular velocit
Temperature-dependent quantum pair potentials and their application to dense partially ionized hydrogen plasmas
Extending our previous work \cite{filinov-etal.jpa03ik} we present a detailed
discussion of accuracy and practical applications of finite-temperature
pseudopotentials for two-component Coulomb systems. Different pseudopotentials
are discussed: i) the diagonal Kelbg potential, ii) the off-diagonal Kelbg
potential iii) the {\em improved} diagonal Kelbg potential, iv) an effective
potential obtained with the Feynman-Kleinert variational principle v) the
``exact'' quantum pair potential derived from the two-particle density matrix.
For the {\em improved} diagonal Kelbg potential a simple temperature dependent
fit is derived which accurately reproduces the ``exact'' pair potential in the
whole temperature range. The derived pseudopotentials are then used in path
integral Monte Carlo (PIMC) and molecular dynamics (MD) simulations to obtain
thermodynamical properties of strongly coupled hydrogen. It is demonstrated
that classical MD simulations with spin-dependent interaction potentials for
the electrons allow for an accurate description of the internal energy of
hydrogen in the difficult regime of partial ionization down to the temperatures
of about K. Finally, we point out an interesting relation between the
quantum potentials and effective potentials used in density functional theory.Comment: 18 pages, 11 figure
Immune cells and preterm labour:do invariant NKT cells hold the key?
We have developed our original made-to-measure (M2M) algorithm, PRIMAL, with the aim of modelling the Galactic disc from upcoming Gaia data. From a Milky Way like N-body disc galaxy simulation, we have created mock Gaia data using M0III stars as tracers, taking into account extinction and the expected Gaia errors. In PRIMAL, observables calculated from the N-body model are compared with the target stars, at the position of the target stars. Using PRIMAL, the masses of the N-body model particles are changed to reproduce the target mock data, and the gravitational potential is automatically adjusted by the changing mass of the model particles. We have also adopted a new resampling scheme for the model particles to keep the mass resolution of the N-body model relatively constant. We have applied PRIMAL to this mock Gaia data and we show that PRIMAL can recover the structure and kinematics of a Milky Way like barred spiral disc, along with the apparent bar structure and pattern speed of the bar despite the galactic extinction and the observational errors
In Defense of the Land Residual Theory and the Absence of a Business Value Component for Retail Property
The temptation is strong for arguing that property values can be broken down into land, improvements, and business value, as only land and improvements are subject to property tax. As sympathetic as the authors are to this motivation, the notion of a long-run business value component for retail property is refuted and the land residual value theory reasserted, while at the same time admitting the possibility of first owner entrepreneurial or development-based value creation. It is argued that any excess property productivity will eventually become attached to the land, and last that option values are an important aspect of land values that would be affected when suggesting that the appropriate value of a given property is the cost of substituting adjacent property.
Quasi-one and two-dimensional transitions of gases adsorbed on nanotube bundles
Grand canonical Monte Carlo simulations have been performed to determine the
adsorption behavior of Ar and Kr atoms on the exterior surface of a rope
(bundle) consisting of many carbon nanotubes. The computed adsorption isotherms
reveal phase transitions associated with the successive creation of quasi-one
dimensional lines of atoms near and parallel to the intersection of two
adjacent nanotubes.Comment: 12 pages, 6 figures, submitted to J. Chem. Phy
Simulation of spacecraft attitude dynamics using TREETOPS and model-specific computer Codes
The simulation of spacecraft attitude dynamics and control using the generic, multi-body code called TREETOPS and other codes written especially to simulate particular systems is discussed. Differences in the methods used to derive equations of motion--Kane's method for TREETOPS and the Lagrangian and Newton-Euler methods, respectively, for the other two codes--are considered. Simulation results from the TREETOPS code are compared with those from the other two codes for two example systems. One system is a chain of rigid bodies; the other consists of two rigid bodies attached to a flexible base body. Since the computer codes were developed independently, consistent results serve as a verification of the correctness of all the programs. Differences in the results are discussed. Results for the two-rigid-body, one-flexible-body system are useful also as information on multi-body, flexible, pointing payload dynamics
A Universal Temperature Profile for Galaxy Clusters
We investigate the predicted present-day temperature profiles of the hot,
X-ray emitting gas in galaxy clusters for two cosmological models - a current
best-guess LCDM model and standard cold dark matter (SCDM). Our
numerically-simulated "catalogs" of clusters are derived from high-resolution
(15/h kpc) simulations which make use of a sophisticated, Eulerian-based,
Adaptive Mesh-Refinement (AMR) code that faithfully captures the shocks which
are essential for correctly modelling cluster temperatures. We show that the
temperature structure on Mpc-scales is highly complex and non-isothermal.
However, the temperature profiles of the simulated LCDM and SCDM clusters are
remarkably similar and drop-off as
where and . This decrease
is in good agreement with the observational results of Markevitch et al.(1998)
but diverges, primarily in the innermost regions, from their fit which assumes
a polytropic equation of state. Our result is also in good agreement with a
recent sample of clusters observed by BeppoSAX though there is some indication
of missing physics at small radii (). We discuss the
interpretation of our results and make predictions for new x-ray observations
that will extend to larger radii than previously possible. Finally, we show
that, for , our universal temperature profile is consistent with
our most recent simulations which include both radiative cooling and supernovae
feedback.Comment: 8 pages, 6 figures, accepted for publication in ApJ, full-page
version of Fig. 2 at
http://www.cita.utoronto.ca/+AH4-cloken/PAPERS/UTP/f2.ep
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