12,833 research outputs found
Single Superconducting Split-Ring Resonator Electrodynamics
We investigate the microwave electrodynamic properties of a single
superconducting thin film split-ring resonator (SRR). The experiments were
performed in an all-Nb waveguide, with Nb wires and Nb SRRs. Transmission data
showed a high-Q stopband for a single Nb SRR ( at 4.2 K)
below , and no such feature for a Cu SRR, or closed Nb loops, of similar
dimensions. Adding SRRs increased the bandwidth, but decreased the insertion
loss of the features. Placing the Nb SRR into an array of wires produced a
single, elementary negative-index passband ( at 4.2 K).
Changes in the features due to the superconducting kinetic inductance were
observed. Models for the SRR permeability, and the wire dielectric response,
were used to fit the data.Comment: 4 pages, 3 figures, RevTex, submitted to Applied Physics Letters.
Updated version includes mention of bianisotropy, better looking figures, and
different temperature dat
Baryon form factors in a diquark-quark bound state description
Nucleon form factors are calculated in a relativistic diquark--quark picture
based on the Nambu--Jona-Lasinio model. The nucleon wave function is obtained
in a static approximation to the quark exchange interaction between the valence
quark and the diquark. We evaluate the valence quark and --diquark
contribution to the nucleon electromagnetic and weak currents. We find
reasonable electric charge radii, magnetic moments as in the additive diquark
model, and . We discuss the dependence on the model parameters.Comment: 10 pages, latex, 1 postscript figure included (uuencoded
Faddeev approach to the octet and decuplet baryons
A relativistic Faddeev model for the baryon octet is extended to treat the
baryon decuplet. We find that after determining the model parameters in the
mesonic sector the masses of both nucleon and delta deviate by less than 5\%
from the experimental data and show only a very weak dependence on the
constituent quark mass.Comment: 9 page
Designation of newly identified mutagen-sensitive mutations in Neurospora crassa and their linkage data
Two years ago, Dr. Käfer and Dr. Schroeder independently summarized genetic information on mutagen-sensitive mutants in Neurospora crassa (Fungal Genetics Newsletter 35:11-13, 1988; DNA Repair 3:77-98, 1988). So far, 30 genetic loci related to mutagen-sensitivity have been indentified. The mutants are more sensitive to UV, X-rays and/or chemical mutagens than the wild-type strain. We have studied DNA-repair mechanisms of Neurospora for several years. During the study, several mutagen-sensitive mutants were isolated and the mutations were mapped. To confirm that they are mutations in new genes, we tested allelism between these mutations and previously reported mutagen-sensitive mutations. Here, new mutations are listed and new mus numbers are given to them as follows
Analyses of collective flow and space-time evolution based on relativistic hydrodynamical model
We numerically solve fully (3+1)-dimensional relativistic hydrodynamical
equation with the baryon number conservation law. For realistic initial
conditions we adopt the results from the event generator (URASiMA). Using this
model we discuss collective flow.Comment: 4 pages, 11 figures, to apper in Proceedings of Quark Matter '9
Scalable Parallel Numerical Constraint Solver Using Global Load Balancing
We present a scalable parallel solver for numerical constraint satisfaction
problems (NCSPs). Our parallelization scheme consists of homogeneous worker
solvers, each of which runs on an available core and communicates with others
via the global load balancing (GLB) method. The parallel solver is implemented
with X10 that provides an implementation of GLB as a library. In experiments,
several NCSPs from the literature were solved and attained up to 516-fold
speedup using 600 cores of the TSUBAME2.5 supercomputer.Comment: To be presented at X10'15 Worksho
Spin Gap of S=1/2 Heisenberg Model on Distorted Diamond Chain
We study the spin gap of the S=1/2 Heisenberg model on the distorted diamond
chain, which is recently proposed to represent magnetic properties of Cu_3 Cl_6
(H_2 O)_2 2H_8 C_4 SO_2. This model is composed of stacked trimers and has
three kinds of exchange interactions J_1, J_2 and J_3. Using the numerical
diagonalization, we obtain a contour map of the spin gap in the J_2/J_1-J_3/J_1
plane. We argue possible values of the exchange constants based on the contour
map and the observed value of the spin gap.Comment: 2 pages, 4 figure
Analysis of one- and two-particle spectra at RHIC based on a hydrodynamical model
We calculate the one-particle hadronic spectra and correlation functions of
pions based on a hydrodynamical model. Parameters in the model are so chosen
that the one-particle spectra reproduce experimental results of
GeV Au+Au collisions at RHIC. Based on the numerical solution,
we discuss the space-time evolution of the fluid. Two-pion correlation
functions are also discussed. Our numerical solution suggests the formation of
the quark-gluon plasma with large volume and low net baryon density.Comment: LaTeX, 4pages, 4 figures. To appear in the proceedings of Fourth
International Conference on Physics and Astrophysics of Quark-Gluon Plasma
(ICPAQGP-2001), Nov 26-30, 2001, Jaipur, Indi
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