10,146 research outputs found
Tensor Spectra Templates for Axion-Gauge Fields Dynamics during Inflation
gauge fields can generate large gravitational waves during inflation,
if they are coupled to an axion which can be either the inflaton or a spectator
field. The shape of the produced tensor power spectrum depends
on the form of the axion potential. We derive analytic expressions and provide
general templates for for various types of the spectator axion
potential. Furthermore, we explore the detectability of the oscillatory
feature, which is present in in the case of an axion monodromy
model, by possible future CMB B-mode polarization observations.Comment: 31 pages, 11 figure
Optical Constants of Silver and Barium in the Vacuum Ultraviolet Spectral Region
Optical constants of silver and barium in vacuum ultraviolet spectral regio
Studies on Regioselective Binding Mode of Steroid Molecules in Homology Modeled Cytochrome P450-2C11
In this study, we investigated the regioselective binding mode of steroid molecules and structure requirements for steroid molecules for 16[alpha]-hydroxylation by Cytochrome P450-2C11. Docking study by using the homology Cytochrome P450-2C11 indicated that 16[alpha]-hydroxylation is favored with steroidal molecules possessing the following components, 1) a bent A-B ring configuration (5[beta]-reduced), 2) C-3[alpha]-hydroxyl group, 3) C-17[beta]-acetyl group, and 4) methyl group at both the C-18 and C-19. These respective steroid components requirements such as A-B ring configuration and functional groups at C-3 and C-17 were defined as the inhibitory contribution factor. Overall results by rat CYP2C11 revealed that steroidal structure requirements resulted in causing an effective inhibition of [^3^H]progesterone 16[alpha]-hydroxylation by the adult male rat liver microsome. As far as docking of homology modeled CYP2C11 against investigated steroids is concerned, they are docked at the active site superimposed with flurbiprofen. It was also found that the distance between heme iron and C16[alpha]-H was between 4 to 6 Å and that the related angle was in the range of 180±45°
Delta Effects in Pion-Nucleon Scattering and the Strength of the Two-Pion-Exchange Three-Nucleon Interaction
We consider the relationship between P-wave pi-N scattering and the strength
of the P-wave two-pion-exchange three-nucleon interaction (TPE3NI). We explain
why effective theories that do not contain the delta resonance as an explicit
degree of freedom tend to overestimate the strength of the TPE3NI. The
overestimation can be remedied by higher-order terms in these ``delta-less''
theories, but such terms are not yet included in state-of-the-art chiral EFT
calculations of the nuclear force. This suggests that these calculations can
only predict the strength of the TPE3NI to an accuracy of +/-25%.Comment: 13 pages, 2 figures, uses eps
Mechanism of Anomalous Tunneling in Condensed Bose System
We clarify the origin of anomalous tunneling [Yu. Kagan et al. Phys. Rev.
Lett. 90 (2003) 130402] i.e. the perfect transmission at low energy limit of
tunneling of phonon excitations across the potential barrier separating two
Bose condensates. The perfect transmission is a consequence of the coincidence
of the wave function of the excited state at low energy limit and the
macroscopic wave function of the condensate. We show that the perfect
transmission at low energy occurs even at finite temperatures within the scheme
of Popov approximation.Comment: 4 pages 1 figur
Transport properties and electronic states of the thermoelectric oxide NaCo_2O_4
Physical properties of the thermoelectric oxide NaCo_2O_4 are briefly
reviewed. The high thermoelectric properties of this material are attributed to
the substantially enhanced effective mass, which comes from the large entropy
of Co in the low spin state. The large entropy confined in the CoO_2
block causes a spin-density-wave transition at 22 K upon Cu substitution for
Co, which can be regarded as ``order from disorder''.Comment: 4 Pages, $ figures, Proceedings of The 2nd Hiroshima Workshop:
Transport and Thermal Properties of Advanced Material
Direct Imaging of Spatially Modulated Superfluid Phases in Atomic Fermion Systems
It is proposed that the spatially modulated superfluid phase, or the
Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state could be observed in resonant
Fermion atomic condensates which are realized recently. We examine optimal
experimental setups to achieve it by solving Bogoliubov-de Gennes equation both
for idealized one-dimensional and realistic three-dimensional cases. The
spontaneous modulation of this superfluid is shown to be directly imaged as the
density profiles either by optical absorption or by Stern-Gerlach experiments.Comment: 4 pages, 3 figure
Hyperfine Anomaly of Be Isotopes and Anomalous Large Anomaly in Be
A new result of investigations of the hyperfine structure (hfs) anomaly in Be
isotopes is presented. The hfs constant for Be is obtained by using the
core plus neutron type wave function: . A large hfs anomaly of Be is found, which is mainly due
to a large radius of the halo single particle state.Comment: 14 pages, Late
Effects of boundary roughness on a Q-factor of whispering-gallery-mode lasing microdisk cavities
We perform numerical studies of the effect of sidewall imperfections on the
resonant state broadening of the optical microdisk cavities for lasing
applications. We demonstrate that even small edge roughness causes a drastic
degradation of high-Q whispering gallery (WG) mode resonances reducing their
Q-values by many orders of magnitude. At the same time, low-Q WG resonances are
rather insensitive to the surface roughness. The results of numerical
simulation obtained using the scattering matrix technique, are analyzed and
explained in terms of wave reflection at a curved dielectric interface combined
with the examination of Poincare surface of sections in the classical ray
picture.Comment: 4 pages, 3 figure
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