1,069 research outputs found
Baryonic Matter in the Hidden Local Symmetry Induced from Holographic QCD Models
Baryonic matter is studied in the Skyrme model by taking into account the
roles of , and mesons through the hidden local symmetry
up to terms including the homogeneous Wess-Zumino (hWZ)
terms. Using the master formulas for the low energy constants derived from
holographic QCD models the skyrmion matter properties can be quantitatively
calculated with the input values of the pion decay constant and the
vector meson mass . We find that the hWZ terms are responsible for
the repulsive interactions of the meson. In addition, the
self-consistently included terms with the hWZ terms is found
to increase the half skyrmion phase transition point above the normal nucleon
density.Comment: Contribution to SCGT12 "KMI-GCOE Workshop on Strong Coupling Gauge
Theories in the LHC Perspective", 4-7 Dec. 2012, Nagoya Universit
Observation of the Josephson effect in Pb/(Ba,K)Fe2As2 single crystal junctions
We have fabricated c-axis Josephson junctions on single crystals of
(Ba,K)Fe2As2 by using Pb as the counter electrode in two geometries, planar and
point contact. Junctions in both geometries show resistively shunted junction
I-V curves below the Tc of the counter electrode. Microwave induced steps were
observed in the I-V curves, and the critical currents are suppressed with an
in-plane magnetic field in a manner consistent with the small junction limit.
ICRN products of up to 0.3 mV have been observed in these junctions at 4.2 K.
The observation of Josephson coupling along the c-axis between (Ba,K)Fe2As2 and
a conventional superconductor suggests the existence of a s-wave
superconducting order parameter in this class of iron pnictide superconductors.Comment: 16 pages and 3 figure
Natural durability of some hardwoods imported into korea for deck boards against decay fungi and subterranean termite in accelerated laboratory tests
This study evaluated the natural durability of seven imported hardwoods (bangkirai, burckella, ipe, jarrah, kempas, malas, and merbau) used for deck boards against decay fungi (Fomitopsis palustris, Gloeophyllum trabeum, Trametes versicolor, and Irpex lacteus) and the subterranean termite (Reticulitermes speratus kyushuensis) in accelerated laboratory tests. Ipe, jarrah, and merbau were very durable to fungal attack, with performance comparable to ACQ-treated wood. Bangkirai, burckella, kempas, and malas were classified as durable or moderately durable, depending on the fungal species tested. All wood species except for merbau were highly resistant to termite attack. Termite resistance was similar to ACQ-treated wood. Merbau showed somewhat less than all other species but still significant termite resistance. These results indicated that selected naturally durable hardwood species could inhibit fungal and termite attacks as effectively as ACQ treatment. The natural durability of wood species tested in this study is most likely due to the biocidal extractive content of the wood
Evidence of a universal and isotropic 2\Delta/kBTC ratio in 122-type iron pnictide superconductors over a wide doping range
We have systematically investigated the doping and the directional dependence
of the gap structure in the 122-type iron pnictide superconductors by point
contact Andreev reflection spectroscopy. The studies were performed on single
crystals of Ba1-xKxFe2As2 (x = 0.29, 0.49, and 0.77) and SrFe1.74Co0.26As2 with
a sharp tip of Pb or Au pressed along the c-axis or the ab-plane direction. The
conductance spectra obtained on highly transparent contacts clearly show
evidence of a robust superconducting gap. The normalized curves can be well
described by the Blonder-Tinkham-Klapwijk model with a lifetime broadening. The
determined gap value scales very well with the transition temperature, giving
the 2{\Delta}/kBTC value of ~ 3.1. The results suggest the presence of a
universal coupling behavior in this class of iron pnictides over a broad doping
range and independent of the sign of the doping. Moreover, conductance spectra
obtained on c-axis junctions and ab-plane junctions indicate that the observed
gap is isotropic in these superconductors
Geomagnetic field influences probabilistic abstract decision-making in humans
To resolve disputes or determine the order of things, people commonly use
binary choices such as tossing a coin, even though it is obscure whether the
empirical probability equals to the theoretical probability. The geomagnetic
field (GMF) is broadly applied as a sensory cue for various movements in many
organisms including humans, although our understanding is limited. Here we
reveal a GMF-modulated probabilistic abstract decision-making in humans and the
underlying mechanism, exploiting the zero-sum binary stone choice of Go game as
a proof-of-principle. The large-scale data analyses of professional Go matches
and in situ stone choice games showed that the empirical probabilities of the
stone selections were remarkably different from the theoretical probability. In
laboratory experiments, experimental probability in the decision-making was
significantly influenced by GMF conditions and specific magnetic resonance
frequency. Time series and stepwise systematic analyses pinpointed the
intentionally uncontrollable decision-making as a primary modulating target.
Notably, the continuum of GMF lines and anisotropic magnetic interplay between
players were crucial to influence the magnetic field resonance-mediated
abstract decision-making. Our findings provide unique insights into the impact
of sensing GMF in decision-makings at tipping points and the quantum mechanical
mechanism for manifesting the gap between theoretical and empirical probability
in 3-dimensional living space.Comment: 32 pages, 5 figures, 4 supplementary figures, 2 supplementary tables,
and separate 15 ancillary file
Hidden Local Symmetry and Infinite Tower of Vector Mesons for Baryons
In an effort to access dense baryonic matter relevant for compact stars in a
unified framework that handles both single baryon and multibaryon systems on
the same footing, we first address a holographic dual action for a single
baryon focusing on the role of the infinite tower of vector mesons
deconstructed from five dimensions. To leading order in 't Hooft coupling
, one has the Bogomol'nyi-Prasad-Sommerfield (BPS)
Skyrmion that results when the warping of the bulk background and the
Chern-Simons term in the Sakai-Sugimoto D4/D8- model are
ignored. The infinite tower was found by Sutcliffe to induce flow to a
conformal theory, i.e., the BPS. We compare this structure to that of the SS
model consisting of a 5D Yang-Mills action in warped space and the Chern-Simons
term in which higher vector mesons are integrated out while preserving hidden
local symmetry and valid to and in the chiral counting.
We point out the surprisingly important role of the meson that figures
in the Chern-Simons term that encodes chiral anomaly in the baryon structure
and that may be closely tied to short-range repulsion in nuclear interactions.Comment: 9 pages, REVTeX, to be published in Phys. Rev.
Vortex-glass phase transition and superconductivity in an under- doped (Ba,K)Fe2As2 single crystal
Measurements of magnetotransport and current-voltage (I-V) characteristics up
to 9 T were used to investigate the vortex phase diagram of an under-doped
Measurements of magnetotransport and current-voltage (I-V) characteristics up
to 9 T were used to investigate the vortex phase diagram of an under-doped
(Ba,K)Fe2As2 single crystal with Tc=26.2 K. It is found that the anisotropy
ratio of the upper critical field Hc2 decreases from 4 to 2.8 with decreasing
temperature from Tc to 24.8 K. Consistent with the vortex-glass theory, the I-V
curves measured at H=9 T can be well scaled with the vortex-glass transition
temperature of Tg=20.7 K and critical exponents z=4.1 and v=1. Analyses in
different magnetic fields produced almost identical critical exponent values,
with some variation in Tg, corroborating the existence of the vortex-glass
transition in this under-doped (Ba,K)Fe2As2 single crystal up to 9 T. A vortex
phase diagram is presented, based on the evolution of Tg and Hc2 with magnetic
field.Comment: 23 pages, 7 figures. accepted in Phys. Rev.
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