title: Microwave traps for cold polar molecules

abstract:
  We discuss the possibility of trapping polar molecules in the standing-wave
electromagnetic field of a microwave resonant cavity. Such a trap has several
novel features that make it very attractive for the development of ultracold
molecule sources. Using commonly available technologies, microwave traps can be
built with large depth (up to several Kelvin) and acceptance volume (up to
several cm^3), suitable for efficient loading with currently available sources
of cold polar molecules. Unlike most previous traps for molecules, this
technology can be used to confine the strong-field seeking absolute ground
state of the molecule, in a free-space maximum of the microwave electric field.
Such ground state molecules should be immune to inelastic collisional losses.
We calculate elastic collision cross-sections for the trapped molecules, due to
the electrical polarization of the molecules at the trap center, and find that
they are extraordinarily large. Thus, molecules in a microwave trap should be
very amenable to sympathetic and/or evaporative cooling. The combination of
these properties seems to open a clear path to producing large samples of polar
molecules at temperatures much lower than has been possible previously.


title: Polarization forces in water deduced from single molecule data

abstract:
  Intermolecular polarization interactions in water are determined using a
minimal atomic multipole model constructed with distributed polarizabilities.
Hydrogen bonding and other properties of water-water interactions are
reproduced to fine detail by only three multipoles $\mu_H$, $\mu_O$, and
$\theta_O$ and two polarizabilities $\alpha_O$ and $\alpha_H$, which
characterize a single water molecule and are deduced from single molecule data.

categories: physics.atm-clus cond-mat.soft physics.bio-ph physics.chem-ph


title: A High Flux Source of Cold Rubidium

abstract:
  We report the production of a continuous, slow, and cold beam of 87-Rb atoms
with an unprecedented flux of 3.2 x 10^12 atoms/s and a temperature of a few
milliKelvin. Hot atoms are emitted from a Rb candlestick atomic beam source and
transversely cooled and collimated by a 20 cm long atomic collimator section,
augmenting overall beam flux by a factor of 50. The atomic beam is then
decelerated and longitudinally cooled by Zeeman slowing.


title:
Exactly Integrable Dynamics of Interface between Ideal Fluid and Light
  Viscous Fluid

abstract:
  It is shown that dynamics of the interface between ideal fluid and light
viscous fluid is exactly integrable in the approximation of small surface
slopes for two-dimensional flow. Stokes flow of viscous fluid provides a
relation between normal velocity and pressure at interface. Surface elevation
and velocity potential of ideal fluid are determined from two complex Burgers
equations corresponding to analytical continuation of velocity potential at the
interface into upper and lower complex half planes, respectively. The interface
loses its smoothness if complex singularities (poles) reach the interface.


title: Two problems in Classical Mechanics

abstract:
  A problem about the present structure of dimensional analysis, and another
one about the differences between solids and fluids are suggested. Both
problems appear to have certain foundational aspects.


title: Cell inactivation by diverse ions along their tracks

abstract:
  Irradiation of cell monolayers by monoenergetic ions has made it possible to
establish survival curves at individual values of linear energy transfer. The
two-step model of radiobiological mechanism proposed recently by Judas and
Lokajicek (Judas L., Lokajicek M., 2001: Cell inactivation by ionizing
particles and the shapes of survival curves. J. Theor. Biol. 210 (1), 15-21.,
doi:10.1006/jtbi.2001.2283) has then enabled to show that some significant
deviations from the generally used linear-quadratic model should exist at
higher values of linear energy transfer, which has been also demonstrated
experimentally. However, the new model has been expressed in the form being
applicable rightfully to low-dose parts of survival curves only. It has been
now reformulated to be applicable in analyses of whole survival curves.
Inactivation probabilities after different numbers of particles traversing cell
nuclei (chromosomal systems) may be then derived from experimental data.
Analyses of published data obtained in irradiating by protons and deuterons
will be presented and discussed.


title: On-Shell Description of Stationary Flames

abstract:
  The problem of non-perturbative description of stationary flames with
arbitrary gas expansion is considered. On the basis of the Thomson circulation
theorem an implicit integral of the flow equations is constructed. With the
help of this integral, a simple explicit expression for the vortex mode of the
burnt gas flow near the flame front is obtained. Furthermore, a dispersion
relation for the potential mode at the flame front is written down, thus
reducing the initial system of bulk equations and jump conditions for the flow
variables to a set of integro-differential equations for the flame front
position and the flow velocity at the front. The developed approach is applied
to the case of thin flames. Finally, an asymptotic expansion of the derived
equations is carried out in the case \theta\to 1 where \theta is the gas
expansion coefficient, and a single equation for the front position is obtained
in the second post-Sivashinsky approximation. It is demonstrated, in
particular, how the well-known problem of correct normalization of the front
velocity is resolved in the new approach. It is verified also that in the first
post-Sivashinsky approximation, the new equation reduces to the
Sivashinsky-Clavin equation corrected according to Cambray and Joulin.
Analytical solutions of the derived equations are found, and compared with the
results of numerical simulations.


title: Three's a Crowd: On Causes, Entropy, and Physical Eschatology

abstract:
  Recent discussions of the origins of the thermodynamical asymmetry ("the
arrow of time") by Huw Price and others are critically assessed. This serves as
a motivation for consideration of relationship between thermodynamical and
cosmological causes. Although the project of clarification of the
thermodynamical explanandum is certainly welcome, Price excludes another
interesting option, at least as viable as the sort of Acausal-Particular
approach he favors, and arguably more in the spirit of Boltzmann himself. Thus,
the competition of explanatory projects includes three horses, not two. In
addition, it is the Acausal-Particular approach that could benefit enormously
from dissociation from fanciful ideas of low-entropy future boundary conditions
entertained by Price. Novel revolutionary developments in observational
cosmology, as well as in the nascent astrophysical discipline of physical
eschatology, have obliterated such hypotheses. Also, the Acausal-Anthropic
approach we propose, offers another clear instance of disteleological nature of
the anthropic principle.


title: On the topology of the world exchange arrangements web

abstract:
  Exchange arrangements among different countries over the world are
foundations of the world economy, which generally stand behind the daily
economic evolution. As the first study of the world exchange arrangements web
(WEAW), we built a bipartite network with countries as one type of nodes and
currencies as the other, and found it to have a prominent scale-free feature
with a power-law degree distribution. In a further empirical study of the
currency section of the WEAW, we calculated the clustering coefficients,
average nearest-neighbors degree, and average shortest distance. As an
essential economic network, the WEAW is found to be a correlated disassortative
network with a hierarchical structure, possessing a more prominent scale-free
feature than the world trade web (WTW).


title: Fast and slow nonlinear tearing mode reconnection

abstract:
  This is a brief account of our numerical study of the tearing mode
reconnection. We demonstrate two main points. First, we show that, given
sufficiently small resistivity, the Rutherford regime always exists; larger
values of Delta' require smaller values of resistivity. Rutherford's
negligible-inertia assumption is validated and the asymptotically linear
dependence of the time derivative of the island width on the resistivity and
Delta' is confirmed. Second, we find that, at large Delta', the Rutherford
regime is followed by a nonlinear stage of fast growth linked to X-point
collapse and formation of a current sheet. This causes the reconnection to
become Sweet-Parke (SP) like. The signature resistivity^{1/2} scaling of the
effective island growth rate is, indeed, found in this nonlinear stage. The SP
stage culminates in the saturation of the mode, which can, thus, be achieved
much faster than via Rutherford regime.


title: Zeros of Rydberg-Rydberg Foster Interactions

abstract:
  Rydberg states of atoms are of great current interest for quantum
manipulation of mesoscopic samples of atoms. Long-range Rydberg-Rydberg
interactions can inhibit multiple excitations of atoms under the appropriate
conditions. These interactions are strongest when resonant collisional
processes give rise to long-range C_3/R^3 interactions. We show in this paper
that even under resonant conditions C_3 often vanishes so that care is required
to realize full dipole blockade in micron-sized atom samples.


title: Circular Orbits under Central Forces in Special Relativity

abstract:
  We discuss the existence and stability of circular orbits of a relativistic
point particle moving in a central force field. The stability condition is
somewhat more restrictive in Special Relativity. In the particular case of
attractive central force fields proportional to $1/r^n$, we find the values the
angular momentum may have in circular orbits and show that, unlike in the
non-relativistic limit, the latter are not always stable in Special Relativity
for $2<n<3$.


title:
On Two Complementary Types of Directional Derivative and Flow Field
  Specification in the Classical Field Theory

abstract:
  We discuss a general definition of directional derivative of any tensor flow
field and its practical applications in physics. It is shown that both
Lagrangian and Eulerian descriptions as complementary types of flow field
specifications adopted in modern theoretical hydrodynamics, imply two
complementary types of directional derivatives as corresponding mathematical
constructions. One of them is the Euler substantive derivative useful only in
the contexts of initial Cauchy problem and the other, called here as the local
directional derivative, arises only in the context of so-called final Cauchy
problem. The choice between Lagrangian and Eulerian specifications is
demonstrated to be equivalent to the choice between space-time with Euclidean
or Minkowski metric for any flow field domain, respectively. Mathematical
consideration is developed within the framework of diffeomorfic transformations
for general 4-dimensional differentiable manifold. The analytical expression
for local directional derivative is formulated in form of a theorem. Although
the consideration is developed for ideal one-component (scalar) flow field, it
can be easily generalized to any tensor field. Some implications of the local
directional derivative concept for the classical theory of fields are also
explored.


title:
Observation of modified radiative properties of cold atoms in vacuum
  near a dielectric surface

abstract:
  We have observed a distance-dependent absorption linewidth of cold $^{87}$Rb
atoms close to a dielectric-vacuum interface. This is the first observation of
modified radiative properties in vacuum near a dielectric surface. A cloud of
cold atoms was created using a magneto-optical trap (MOT) and optical molasses
cooling. Evanescent waves (EW) were used to observe the behavior of the atoms
near the surface. We observed an increase of the absorption linewidth with up
to 25% with respect to the free-space value. Approximately half the broadening
can be explained by cavity-quantum electrodynamics (CQED) as an increase of the
natural linewidth and inhomogeneous broadening. The remainder we attribute to
local Stark shifts near the surface. By varying the characteristic EW length we
have observed a distance dependence characteristic for CQED.


title:
Force measurements in positive unipolar wire-to-plane corona discharges
  in air

abstract:
  Measurements of force generated by a positive unipolar wire-to-plane corona
discharge in air are compared with numerical simulations. The generated force
does not depend on the ion or electron mobilities, preventing the influence of
uncertainty and variation of these parameters. A method is described to
simulate the voltage and charge distribution for a wire-to-plane set-up. This
method enables the determination of the transition between unipolar and bipolar
discharges. In the experimental set-up breakdown electric field of air reduces
with increasing discharge current.


title: Multifractal Scaling of Thermally-Activated Rupture Processes

abstract:
  We propose a ``multifractal stress activation'' model combining thermally
activated rupture and long memory stress relaxation, which predicts that
seismic decay rates after mainshocks follow the Omori law $\sim 1/t^p$ with
exponents $p$ linearly increasing with the magnitude $M_L$ of the mainshock and
the inverse temperature. We carefully test this prediction on earthquake
sequences in the Southern California Earthquake catalog: we find power law
relaxations of seismic sequences triggered by mainshocks with exponents $p$
increasing with the mainshock magnitude by approximately $0.1-0.15$ for each
magnitude unit increase, from $p(M_L=3) \approx 0.6$ to $p(M_L=7) \approx 1.1$,
in good agreement with the prediction of the multifractal model.


title:
FDTD Simulation of Exposure of Biological Material to Electromagnetic
  Nanopulses

abstract:
  Ultra-wideband (UWB) electromagnetic pulses of nanosecond duration, or
nanopulses, are of considerable interest to the communications industry and are
being explored for various applications in biotechnology and medicine. The
propagation of a nanopulse through biological matter has been computed in the
time domain using the finite difference-time domain method (FDTD). The approach
required existing Cole-Cole model-based descriptions of dielectric properties
of biological matter to be re-parametrized using the Debye model, but without
loss of accuracy. The approach has been applied to several tissue types.
Results show that the electromagnetic field inside a biological tissue depends
on incident pulse rise time and width. Rise time dominates pulse behavior
inside a tissue as conductivity increases. It has also been found that the
amount of energy deposited by 20 $kV/m$ nanopulses is insufficient to change
the temperature of the exposed material for the pulse repetition rates of 1
$MHz$ or less.


title: Measurement of gamma-T with the gamma-T Quads On and Off

abstract:
  An experimental procedure for measuring gamma-T has been developed and tested
in two different measurements, with the gamma-T quads on and off. The results
were compared to MAD calculations. The discrepancy between the measured gamma-T
and the calculated gamma-T is less than 5%.


title: Indicators of the Energy Error in the Linac to Booster Transfer

abstract:
  The match between the Linac beam energy and the energy determined by the
bending field of the Booster magnets is crucial for rf capture, beam quality,
and the transmission efficiency in a Booster cycle. The observation of the
injection energy match is important for injection tuning. Several signals, such
as phase shift drive (PSD), radial position error (RPOS), synchrotron phase
(SPD), and fast phase error (FPERR), provide consistent information on the
energy match and can be used for a injection match tuning.


title: Booster Synchrotron Frequency Below Transition

abstract:
  The dipole mode synchrotron frequency is a basic beam parameter; it and a few
similarly basic quantities measured at small time intervals serve to
characterize the longitudinal beam dynamics throughout the acceleration cycle.
The effective accelerating voltage, in conjunction with the amount of rf
voltage required for the acceleration, is important for the estimate of the
beam energy loss per turn. The dipole mode frequency can be used to obtain the
effective accelerating rf voltage, providing that it can be measured precisely.
The synchrotron frequency measured from the synchrotron phase detector signal
(SPD) generally agrees well with calculation, and it can be applied for such
purposes as inferring the effective rf voltage.


title: Implications of beam phase and RFSUM measured near transition

abstract:
  Understanding the transition-crossing process is crucial for improving
Booster performance at high intensity. The synchronous phase appears to drop
toward 90 degrees right after transition regardless of beam intensity, more so
at higher beam intensity. The implication is that the effective rf voltage
(RFSUM) will run into a limit right after transition when the synchronous phase
reaches 90 degrees for high intensity beam. A reduction in RFSUM is also
observed at the same time. Solutions, such as raising the rf voltage during the
transition period or controlling the RFSUM reduction by increasing longitudinal
emittance before transition, are potentially important for high intensity
operation.


title:
RF Bucket Reduction as an Experimental Tool for Beam Diagnostics and
  Manipulation

abstract:
  A technique using RF bucket reduction for acquiring information about the
particle distribution in longitudinal phase space has been applied in the
Fermilab Booster. Data sets were obtained at six important time intervals of a
Booster cycle for three different beam intensities. Controlled RF bucket
reduction also provides other opportunities for beam manipulation.


title:
Applying Synchrotron Phase Measurement to the Estimation of Maximum Beam
  Intensity in the Fermilab Booster

abstract:
  It is important to have experimental methods to estimate the maximum beam
intensity for the Fermilab Booster as objective input into long term program
commitments. An important existing limit is set by the available rf power. This
limit is difficult to set a priori because the real longitudinal impedance is
not well known. The synchrotron phase at transition crossing was measured using
both the mountain range plot and the direct phase measurement of the RF
accelerating voltage relative to the beam, and results were consistent. They
were applied to predict 6E12 maximum Booster beam intensity with present
running conditions.


title:
Stability Analysis of the Laser System for the TTF Photoinjector at
  Fermilab

abstract:
  A solid-state laser system that produces a 1MHz pulse train of 800 pulses
with 18 mJ per pulse at the wavelength of 263.5 nm has been developed to meet
the requirements of the TESLA Test Facility (TTF) at Fermilab and in operation
since 1998.[1,2] Besides the production of high charges, high brightness
electron beams, the need for high bunch charge stability requires that each
laser pulse in the pulse train must have the same energy, and the energy per
laser pulse should not vary significantly from shot to shot. This motivates the
stability analysis of the laser system for the TTF photoinjector.


title:
Experimental Estimate of Beam Loading and Minimum rf Voltage for
  Acceleration of High Intensity Beam in the Fermilab Booster

abstract:
  The difference between the rf voltage seen by the beam and the accelerating
voltage required to match the rate of change of the Booster magnetic field is
used to estimate the energy loss per beam turn. Because the rf voltage (RFSUM)
and the synchronous phase can be experimentally measured, they can be used to
calculate the effective accelerating voltage. Also an RFSUM reduction technique
has been applied to measure experimentally the RFSUM limit at which the beam
loss starts. With information on beam energy loss, the running conditions,
especially for the high intensity beam, can be optimized in order to achieve a
higher intensity beam from the Fermilab Booster.


title: A gradient index metamaterial

abstract:
  Metamaterials--artificially structured materials with tailored
electromagnetic response--can be designed to have properties difficult to
achieve with existing materials. Here we present a structured metamaterial,
based on conducting split ring resonators (SRRs), which has an effective
index-of-refraction with a constant spatial gradient. We experimentally confirm
the gradient by measuring the deflection of a microwave beam by a planar slab
of the composite metamaterial over a broad range of frequencies. The gradient
index metamaterial represents an alternative approach to the development of
gradient index lenses and similar optics that may be advantageous, especially
at higher frequencies. In particular, the gradient index material we propose
may be suited for terahertz applications, where the magnetic resonant response
of SRRs has recently been demonstrated.


title:
First observation of feshbach resonances at very low magnetic field in a
  133Cs fountain

abstract:
  One of the main limitations of cesium atomic fountains has been the cold
collision frequency shift. By using a method based on a transfer of population
by adiabatic passage allowing to prepare cold atomic samples with a well
defined ratio of atomic density as well as atom number the collisional shift is
controlled at the 10E-3 of its value. A calibration of Zeeman sub-states
contribution to the clock shift as a function of the field has been performed.
Feshbach resonances have been observed for the first time at very low magnetic
field and with a very good resolution. A Monte Carlo simulation has been
performed and could fit properly some of experimental data. This constrains
some parameters of the theory of collisions.


title: Lithium in strong magnetic fields

abstract:
  The electronic structure of the lithium atom in a strong magnetic field 0 <=
gamma <= 10 is investigated. Our computational approach is a full configuration
interaction method based on a set of anisotropic Gaussian orbitals that is
nonlinearly optimized for each field strength. Accurate results for the total
energies and one-electron ionization energies for the ground and several
excited states for each of the symmetries ^20^+, ^2(-1)^+, ^4(-1)^+, ^4(-1)^-,
^2(-2)^+, ^4(-2)^+, $^4(-3)^{+}$ are presented. The behaviour of these energies
as a function of the field strength is discussed and classified. Transition
wave lengths for linear and circular polarized transitions are presented as
well.


title:
Latitudinal dependence of low cloud amount on cosmic ray induced
  ionization

abstract:
  A significant correlation between the annual cosmic ray flux and the amount
of low clouds has recently been found for the past 20 years. However, of the
physical explanations suggested, none has been quantitatively verified in the
atmosphere by a combination of modelling and experiment. Here we study the
relation between the global distributions of the observed low cloud amount and
the calculated tropospheric ionization induced by cosmic rays. We find that the
time evolution of the low cloud amount can be decomposed into a long-term trend
and inter-annual variations, the latter depicting a clear 11-year cycle. We
also find that the relative inter-annual variability in low cloud amount
increases polewards and exhibits a highly significant one-to-one relation with
inter-annual variations in the ionization over the latitude range
20--55$^\circ$S and 10--70$^\circ$N. This latitudinal dependence gives strong
support for the hypothesis that the cosmic ray induced ionization modulates
cloud properties.


title: Gravitation as a weak electromagnetism and other issues

abstract:
  In the context of a Planck scale underpinning for the universe, we argue that
both gravitation and electromagnetism can be characterized in a unified way, in
a Sakharov like description. We also consider the issue of observed gamma
radiation, which recent observations seem to indicate are caused by the
annihilation of exotic $Mev$ particles, as indeed was theoretically predicted
earlier. Some other problems are also considered.


title: Structure of the most singular vortices in fully developed turbulence

abstract:
  Using high Reynolds number experimental data, we search for most dissipative,
most intense vortices. These structures possess a scaling predicted by
log-Poisson model for the dissipation field $\epsilon_r$. These new
experimental data suggest that the most intense structures have co-dimension
less than 2. The log-Poisson statistics is compared with log-binomial which
follows from the random $\beta$-model.


title:
Experimental Demonstration of Signal-to-Noise-Ratio Improvement of
  Fourier-Domain Optical Coherence Tomography

abstract:
  A recent advance in optical coherence tomography (OCT), termed swept-source
OCT, is generalized into a new technique, Fourier-domain OCT. It represents a
realization of a full-field OCT system in place of the conventional serial
image acquisition in transverse directions typically implemented in
"flying-spot" mode. To realize the full-field image acquisition, a Fourier
holography system illuminated with a swept-source is employed instead of a
Michelson interferometer commonly used in OCT. Fourier-domain OCT offers a new
leap in signal-to-noise ratio improvement, as compared to flying-spot OCT
systems. This paper presents experimental evidence that the signal-to-noise
ratio of this new technique is indeed improved.


title:
Vortex-like surface wave and its role in the transient phenomena of
  meta-material focusing

abstract:
  We show that a slab of meta-material (with $\epsilon=\mu=-1+i\Delta$)
possesses a vortex-like surface wave with no ability to transport energy, whose
nature is completely different from a localized mode or a standing wave.
Through computations based on a rigorous time-dependent Green's function
approach, we demonstrate that such a mode inevitably generates characteristic
image oscillations in two dimensional focusing with even a monochromatic
source, which were observed in many numerical simulations, but such
oscillations are weak in three dimensional focusing.


title: The Inverted Big-Bang

abstract:
  Our universe appears to have been created not out of nothing but from a
strange space-time dust. Quantum geometry (loop quantum gravity) makes it
possible to avoid the ominous beginning of our universe with its physically
unrealistic (i.e. infinite) curvature, extreme temperature, and energy density.
This could be the long sought after explanation of the big-bang and perhaps
even opens a window into a time before the big-bang: Space itself may have come
from an earlier collapsing universe that turned inside out or inverted and
began to expand again. - Key words: Loop quantum cosmology, Wheeler-DeWitt
equation, singularity, Abhay Ashtekar, Martin Bojowald.


title: Beryllium in strong magnetic fields

abstract:
  We investigate the electronic structure of the beryllium atom subjected to a
strong magnetic field in the regime 0 <= gamma <= 10 a.u. The ground as well as
many excited states of spin singlet, triplet and quintet multiplicity covering
the magnetic quantum numbers |M|=0,1,3,6 for both positive and negative
z-parity are discussed and analyzed. Total and one-particle ionization energies
are presented. Transition wavelengths as a function of the field strengths for
allowed dipole transitions are provided.


title:
An Analytical Theory for the Early Stage of the Development of
  Hurricanes: Part I

abstract:
  A theoretical formulation for the early stage (Tropical Storm stage) of
hurricane development is proposed. These solutions are not only consistent with
observations but also offer some new insights into hurricane properties. This
is the first time a theoretical model for the early growing of hurricanes is
proposed for which analytical solutions have been found, based on an assumption
of a positive feedback of a self-induced developing system.


title:
Altitude dependence of atmospheric temperature trends: Climate models
  versus observation

abstract:
  As a consequence of greenhouse forcing, all state of the art general
circulation models predict a positive temperature trend that is greater for the
troposphere than the surface. This predicted positive trend increases in value
with altitude until it reaches a maximum ratio with respect to the surface of
as much as 1.5 to 2.0 at about 200 to 400 hPa. However, the temperature trends
from several independent observational data sets show decreasing as well as
mostly negative values. This disparity indicates that the three models examined
here fail to account for the effects of greenhouse forcings.


title: Disparity of tropospheric and surface temperature trends: New evidence

abstract:
  Observations suggest that the earth's surface has been warming relative to
the troposphere for the last 25 years; this is not only difficult to explain
but also contrary to the results of climate models. We provide new evidence
that the disparity is real. Introducing an additional data set, R2 2 meter
temperatures, a diagnostic variable related to tropospheric temperature
profiles, we find trends derived from it to be in close agreement with
satellite measurements of tropospheric temperature. This suggests that the
disparity likely is a result of near-surface processes. We find that the
disparity does not occur uniformly across the globe, but is primarily confined
to tropical regions which are primarily oceanic. Since the ocean measurements
are sea surface temperatures, we suggest that the disparity is probably
associated with processes at the ocean-atmosphere interface. Our study thus
makes unlikely some of the explanations advanced to account for the disparity;
it also demonstrates the importance of distinguishing between land, sea and air
measurements


title: Comments on the Discrete Variable Representation

abstract:
  We discuss the application of the Discrete Variable Representation to
Schr\"odinger problems which involve singular Hamiltonians. Unlike recent
authors who invoke transformations to rid the eigenvalue equation of
singularities at the cost of added complexity, we show that an approach based
solely on an orthogonal polynomial basis is adequate, provided the
Gauss-Lobatto or Gauss-Radau quadrature rule is used. This ensures that the
mesh contains the singular points and by simply discarding the DVR functions
corresponding to those points, all matrix elements become well-behaved, the
boundary conditions are satisfied and the calculation is rapidly convergent.
The accuracy of the method is demonstrated by applying it to the hydrogen atom.
We emphasize that the method is equally capable of describing bound states and
continuum solutions.


title: Redshift and Energy Conservation

abstract:
  It has always been considered a serious error to treat the cosmological
redshift as a Doppler velocity effect rather than the result of space
expansion. It is demonstrated here that in practical terms this is not the
case, and that the apparent distance - redshift relation derived from a Doppler
interpretation is reasonably consistent with supernova data (though not as good
as the standard model with dark energy). The normal Doppler effect is examined
in detail and shown to conserve energy as expected. Because of the equivalence
between the general relativistic space expansion paradigm and the Doppler
effect (as demonstrated) the long-standing problem of energy loss associated
with the expansion of the Universe is treated in a similar manner to the normal
well-behaved Doppler effect. The mechanism by which energy is conserved with
the normal Doppler shift is applied to the cosmological redshift and the energy
violation disappears. However, an additional luminosity-dependent recession
factor is introduced. The effect on astronomical objects is examined and it is
found to add only a small additional redshift to a body generating power by
nuclear means but can be very large for objects powered by gravity. A possible
connection to the claimed anomalous redshift of quasars is considered.


title: Mach's Principle

abstract:
  We briefly review the history of Mach's principle and discuss its
significance in the light of modern physics.

categories: physics.hist-ph astro-ph gr-qc physics.gen-ph


title:
Relationship between Horizontal Flow Velocity and Cell Lifetime for
  Supergranulation

abstract:
  A study of 50 supergranular cells obtained from SOHO Dopplergrams was
undertaken in order to investigate the relationship between the lifetime ($T$)
and the horizontal flow velocity ($v_h$) of the cells. For this sample we find
that the two parameters are correlated with a relation $v_h\propto T^{0.5}$ and
$T$ is identified with the eddy turn-over time. This is in agreement with the
turbulent convective model of the solar atmosphere where the velocity spectrum
of supergranular field given by '$v_h \propto L^{1/3}$' can be identified with
the Kolmogorov spectrum for the eddy size $L$.


title: Exponential versus linear amplitude decay in damped oscillators

abstract:
  We comment of the widespread belief among some undergraduate students that
the amplitude of any harmonic oscillator in the presence of any type of
friction, decays exponentially in time. To dispel that notion, we compare the
amplitude decay for a harmonic oscillator in the presence of (i) viscous
friction and (ii) dry friction. It is shown that, in the first case, the
amplitude decays exponentially with time while in the second case, it decays
linearly with time.


title:
On the existence of statistics intermediate between those of Fermi-Dirac
  and Bose-Einstein

abstract:
  Once again the possibility of the existence of particle statistics
intermediate between those of Fermi-Dirac and Bose-Einstein surfaces. Here
attention is drawn to the fact that some fifteen years ago it was shown that
such so-called 'intermediate' statistics correspond to no physical process and
the stationary probability distributions of intermediate statistics are not
compatible with any mechanism which allows a variation between Fermi-Dirac and
Bose-Einstein statistics.


title: A link between an ice age era and a rapid polar shift

abstract:
  The striking asymmetry of the ice cover during the Last Global Maximum
suggests that the North Pole was in Greenland and then rapidly shifted to its
present position in the Arctic See. A scenario which causes such a rapid
geographic polar shift is physically possible. It involves an additional
planet, which disappeared by evaporation within the Holocene. This is only
possible within such a short period, if the planet was in an extremely
eccentric orbit and hot. Then, since this produced an interplanetary gas cloud,
the polar shift had to be preceded by a cold period with large global
temperature variations during several million years.


title:
Structural Effects of Small Molecules on Phospholipid Bilayers
  Investigated by Molecular Simulations

abstract:
  We summarize and compare recent Molecular Dynamics simulations on the
interactions of dipalmitoylphosphatidylcholine (DPPC) bilayers in the liquid
crystalline phase with a number of small molecules including trehalose, a
disaccharide of glucose, alcohols, and dimethylsulfoxide (DMSO). The sugar
molecules tend to stabilize the structure of the bilayer as they bridge
adjacent lipid headgroups. They do not strongly change the structure of the
bilayer. Alcohols and DMSO destabilize the bilayer as they increase its area
per molecule in the bilayer plane and decrease the order parameter. Alcohols
have a stronger detrimental effect than DMSO. The observables which we compare
are the area per molecule in the plane of the bilayer, the membrane thickness,
and the NMR order parameter of DPPC hydrocarbon tails. The area per molecule
and the order parameter are very well correlated whereas the bilayer thickness
is not necessarily correlated with them.


title: Evidence for a Universe expanding at the speed of light

abstract:
  Although big bang cosmology effectively models even the most puzzling
observational data, it offers no insight into why the cosmological expansion
should occur at all. In this paper it is suggested that a finite Universe poses
particular problems at the boundary point when time begins. An alternative
model is proposed where the expansion arises from a need to incorporate the
boundary effects into observation in a consistent way that avoids
discontinuities and singularities. The theory predicts that the Universe is
expanding at a constant rate, the speed of light, and is a reasonable match for
apparent magnitude - redshift data for both supernovae and 3CR radio sources
using only one adjustable parameter, the absolute visual magnitude. Values of
-21.8 for the 3CR galaxies and -25.2 for the 3CR quasars give the best fit. The
new model is mapped to standard cosmology and predicts a deceleration parameter
with a time dependence of the form q(t)=1-2t/T, where T is the current age of
the Universe. The model of expanding space-time with expansion retarded by
gravity is usually associated with Friedmann's equation(s) but here is
considered erroneous, giving rise to spurious concepts such as dark energy - in
this new model mass and gravity have no effect on expansion.


title: Atomic gallium laser spectroscopy with violet/blue diode lasers

abstract:
  We describe the operation of two GaN-based diode lasers for the laser
spectroscopy of gallium at 403 nm and 417 nm. Their use in an external cavity
configuration enabled the investigation of absorption spectroscopy in a gallium
hollow cathode. We have analyzed the Doppler broadened profiles accounting for
hyperfine and isotope structure and extracting both the temperature and
densities of the neutral atomic sample produced in the glow discharge. We have
also built a setup to produce a thermal atomic beam of gallium. Using the
GaN-based diode lasers we have studied the laser induced fluorescence and
hyperfine resolved spectra of gallium.


title: Electron--phonon coupling and anharmonic effects in metal clusters

abstract:
  The periods of the harmonic oscillations of the ion core of charged sodium
clusters around the equilibrium shapes are considered. It is found that these
periods are of the order of magnitude of the experimentally measured relaxation
times of the plasmons, which suggests the importance of the electron-ion
coupling and stresses the role played by the electron-phonon interaction in the
dissipation of the plasmon energy. The relation of the process to fission is
briefly discussed.


title:
A simple method for the determination of the structure of ultrashort
  relativistic electron bunches

abstract:
  In this paper we propose a new method for measurements of the longitudinal
profile of 100 femtosecond electron bunches for X-ray Free Electron Lasers
(XFELs). The method is simply the combination of two well-known techniques,
which where not previously combined to our knowledge. We use seed 10-ps 1047 nm
quantum laser to produce exact optical replica of ultrafast electron bunches.
The replica is generated in apparatus which consists of an input undulator
(energy modulator), and the short output undulator (radiator) separated by a
dispersion section. The radiation in the output undulator is excited by the
electron bunch modulated at the optical wavelength and rapidly reaches 100
MW-level peak power. We then use the now-standard method of ultrashort laser
pulse-shape measurement, a tandem combination of autocorrelator and spectrum
(FROG -- frequency resolved optical gating). The FROG trace of the optical
replica of electron bunch gives accurate and rapid electron bunch shape
measurements in a way similar to a femtosecond oscilloscope. Real-time
single-shot measurements of the electron bunch structure could provide
significant information about physical mechanisms responsible for generation
ultrashort electron bunches in bunch compressors. The big advantage of proposed
technique is that it can be used to determine the slice energy spread and
emittance in multishot measurements. It is possible to measure bunch structure
completely, that is to measure peak current, energy spread and transverse
emittance as a function of time. We illustrate with numerical examples the
potential of the proposed method for electron beam diagnostics at the European
X-ray FEL.


title: Discovery of dumbbell-shaped Cs*He_n exciplexes in solid He 4

abstract:
  We have observed several new spectral features in the fluorescence of cesium
atoms implanted in the hcp phase of solid helium following laser excitation to
the 6$^{2}$P states. Based on calculations of the emission spectra using
semiempirical Cs-He pair potentials the newly discovered lines can be assigned
to the decay of specific Cs*He$_{n}$ exciplexes: an apple-shaped Cs$(A\Pi
_{3/2})$He$_{2}$ and a dumbbell-shaped Cs$(A\Pi_{1/2}) $He$_{n}$ exciplex with
a well defined number $n$ of bound helium atoms. While the former has been
observed in other enviroments, it was commonly believed that exciplexes with
$n>2$ might not exist. The calculations suggest Cs$(A\Pi_{1/2}) $He$_{6}$ to be
the most probable candidate for that exciplex, in which the helium atoms are
arranged on a ring around the waist of the dumbbell shaped electronic density
distribution of the cesium atom.


title:
Holographic imaging with multimode, large free spectral range lasers in
  photorefractive sillenite crystals

abstract:
  The holographic imaging of rigid objects with diode lasers emitting in many
wavelengths in a sillenite Bi12TiO20 photorefractive crystal is both
theoretically and experimentally investigated. It is shown that, due to the
multi-wavelength emission and the typically large free spectral range of this
light source, contour fringes appear on the holographic image corresponding to
the surface relief, even in single-exposure recordings. The influence of the
number of emitted modes on the fringe width is analysed, and the possible
applications of the contour fringes in the field of optical metrology are
pointed out.


title: Physical model for the latent heat of fusion

abstract:
  The atomic movement induced on melting has to overcome a viscous drag
resistance. It is suggested that the latent heat of fusion supplies the
required energy for this physical process. The viscosity model introduced here
allows computation of the latent heat from viscosity, molar volume, melting
temperature, and atomic mass and diameter. The correlation between these
parameters and the latent heat of 14 elements with body and face centered cubic
structures was exceptional, with the correlation coefficients of 0.97 and 0.95
respectively.


title: Detection of coherent reflections with GPS bipath interferometry

abstract:
  Results from a GPS reflectometry experiment with a 12 channel ground-based
GPS receiver above two lakes in the Bavarian Alps are presented. The receiver
measures in open-loop mode the coarse/aquisition code correlation function of
the direct and the reflected signal of one GPS satellite simultaneously. The
interference between the coherently reflected signal and a model signal, which
is phase-locked to the direct signal, causes variations in the amplitude of the
in-phase and quad-phase components of the correlation sums. From these
amplitude variations the relative altimetric height is determined within a
precision of 2 cm.


title: Principle of relativity in physics and in epistemology

abstract:
  The conceptual evolution of principle of relativity in the theory of special
relativity is discussed in detail. It is intimately related to a series of
difficulties in quantum mechanics,relativistic quantum mechanics and quantum
field theory as well as to new predictions about antigravity and tachyonic
neutrinos etc.


title: Huygens description of resonance phenomena in subwavelength hole arrays

abstract:
  We develop a point-scattering approach to the plane-wave optical transmission
of subwavelength metal hole arrays. We present a real space description instead
of the more conventional reciprocal space description; this naturally produces
interfering resonant features in the transmission spectra and makes explicit
the tensorial properties of the transmission matrix. We give transmission
spectra simulations for both square and hexagonal arrays; these can be
evaluated at arbitrary angles and polarizations.


title: Atom chips in the real world: the effects of wire corrugation

abstract:
  We present a detailed model describing the effects of wire corrugation on the
trapping potential experienced by a cloud of atoms above a current carrying
micro wire. We calculate the distortion of the current distribution due to
corrugation and then derive the corresponding roughness in the magnetic field
above the wire. Scaling laws are derived for the roughness as a function of
height above a ribbon shaped wire. We also present experimental data on micro
wire traps using cold atoms which complement some previously published
measurements and which demonstrate that wire corrugation can satisfactorily
explain our observations of atom cloud fragmentation above electroplated gold
wires. Finally, we present measurements of the corrugation of new wires
fabricated by electron beam lithography and evaporation of gold. These wires
appear to be substantially smoother than electroplated wires.


title:
Construction of accurate Kohn-Sham potentials for the lowest states of
  the helium atom: Accurate test of the ionization-potential theorem

abstract:
  Accurate local Kohn-Sham potentials have been constructed for the ground
$1s^2 ^1S$ state and, in particular, for the lowest triplet $1s2s ^{3}S$ state
of the helium atom, using electron densities from many-body calculations and
the procedure of van Leeuwen and Baerends (Phys. Rev. A{\bf49}, 2138 (1994)).
The resulting Kohn-Sham orbitals reproduce the many-body densities very
accurately, and furthermore we have demonstrated that the negative of the
energy eigenvalue of the outermost electron orbital agrees with the
corresponding ionization energy with extreme accuracy. The procedure is also
applied to the Hartree-Fock density of the $1s2s ^{3}S$ state, and the
Kohn-Sham eigenvalue of the $2s$ orbital is found to agree very well with the
corresponding Hartree-Fock eigenvalue, which is the negative of the ionization
energy in this model due to Koopmans' theorem. The results for the $1s2s ^{3}S$
state clearly demonstrate that there is no conflict between the locality of the
Kohn-Sham potential and the exclusion principle, as claimed by Nesbet (Phys.
Rev. A{\bf58}, R12 (1998)).


title:
Electrodynamics under a Possible Alternative to the Lorentz
  Transformation

abstract:
  A generalization of the classical electrodynamics for systems in absolute
motion is presented using a possible alternative to the Lorentz transformation.
The main hypothesis assumed in this work are: a) The inertial transformations
relate two inertial frames: the privileged frame S and the moving frame S' with
velocity v with respect to S. b) The transformation of the fields from S to the
moving frame S' is given by H'=a(H - v D) and E'=a(E + v B) where a is a matrix
whose elements depend of the absolute velocity of the system. c) The
constitutive relations in the moving frame S' are given by D'= \epsilon E', B'=
\mu H' and J'=\eta E'. It is found that Maxwell's equations, which are
transformed to the moving frame, take a new form depending on the absolute
velocity of the system. Moreover, differing from classical electrodynamics, it
is proved that the electrodynamics proposed explains satisfactorily the Wilson
effect.


title:
Four-wave mixing of linear waves and solitons in fibres with higher
  order dispersion

abstract:
  We derive phase-matching conditions for four-wave mixing between solitons and
linear waves in optical fibres with arbitrary dispersion and demonstrate
resonant excitation of new spectral components via this process.


title: BFKL, MM, Alpert-Rokhlin's transform, FFTW, ARPACK and all that

abstract:
  The evolution equation for $q \bar q$ production introduced by Marchesini and
Mueller posed some intriguing mathematical puzzles, both numerical and
analytic. I give a detailed account of the numerical approach which led
eventually to the exact solution. While part of the work was in fact along a
wrong track, it turns out that some of the techniques involved are interesting
in their own and applicable to many other problems, i.e. to the numerical study
of Ricci flows.


title: SI, CGSG, and ch units: metrology and special relativity

abstract:
  Invited report at the 8th Meeting of the Working Group ``Base units and
fundamental constants'' of the French Academy of Sciences. June 14, 2004.
  The text consists of seven sections:
  1. Great importance of SI. 2. The necessity of updating SI. 3. Special
relativity: four-dimensional quantities. 4. Maxwell equations in vacuum in CGSG
units. 5. Maxwell equations in vacuum in SI. 6. $c \hbar$ units. 7. Systems
CGSG and $c \hbar$ should be legalized.


title:
Chaotic quantum ratchets and filters with cold atoms in optical
  lattices: properties of Floquet states

abstract:
  Recently, cesium atoms in optical lattices subjected to cycles of
unequally-spaced pulses have been found to show interesting behavior: they
represent the first experimental demonstration of a Hamiltonian ratchet
mechanism, and they show strong variability of the Dynamical Localization
lengths as a function of initial momentum. The behavior differs qualitatively
from corresponding atomic systems pulsed with equal periods, which are a
textbook implementation of a well-studied quantum chaos paradigm, the quantum
delta-kicked particle (delta-QKP). We investigate here the properties of the
corresponding eigenstates (Floquet states) in the parameter regime of the new
experiments and compare them with those of the eigenstates of the delta-QKP at
similar kicking strengths. We show that, with the properties of the Floquet
states, we can shed light on the form of the observed ratchet current as well
as variations in the Dynamical Localization length.


title: Sharp vorticity gradients in two-dimensional hydrodynamic turbulence

abstract:
  The appearance of sharp vorticity gradients in two-dimensional hydrodynamic
turbulence and their influence on the turbulent spectra is considered. We have
developed the analog of the vortex line representation as a transformation to
the curvilinear system of coordinates moving together with the di-vorticity
lines. Compressibility of this mapping can be considered as the main reason for
the formation of the vorticity discontinuities at high Reynolds numbers. For
two-dimensional turbulence in the case of strong anisotropy the vorticity
discontinuities can generate spectra with the fall-off at large $k$
proportional to $k^{-3}$ resembling the Kraichnan spectrum for the enstrophy
cascade. For turbulence with weak anisotropy the $k$ dependence of the spectrum
due to discontinuities coincides with that of the Saffman spectrum: $k^{-4}$.
We have compared the analytical predictions with direct numerical solutions of
the two-dimensional Euler equation for decaying turbulence. We observe that the
di-vorticity is reaching very high values and is distributed locally in space
along piecewise straight lines. Thus, indicating strong anisotropy and
accordingly we found a spectrum close to the $k^{-3}$-spectrum.


title:
Elementary Integration Methods for Velocity Excitations in Displacement
  Digital Waveguides

abstract:
  Elementary integration methods for waveguides are compared. One using
non-local loading rules based on Heaviside step functions, one using input side
integration and one using integration of the output of traveling velocity
waves. We show that most approaches can be made consistent with the wave
equation in principle, under proper circumstances. Of all methods studied the
Heaviside method is the only method shown to not suffer from undesirable
numerical difficulties and amendable to standard waveguide loop filtering
practices, yet it gives incorrect results for Neumann boundary conditions. We
also discuss localized velocity excitations, time-limited input-side
excitations and the relation of loop filters to wave variable type.


title:
Polarization control and sensing with two-dimensional coupled photonic
  crystal microcavity arrays

abstract:
  We have experimentally studied polarization properties of the two-dimensional
coupled photonic crystal microcavity arrays, and observed a strong polarization
dependence of the transmission and reflection of light from the structures -
the effects that can be employed in building miniaturized polarizing optical
components. Moreover, by combining these properties with a strong sensitivity
of the coupled bands on the surrounding refractive index, we have demonstrated
a detection of small refractive index changes in the environment, which is
useful for construction of bio-chemical sensors.


title:
Ultra-large bandwidth hollow-core guiding in all-silica Bragg fibers
  with nano-supports

abstract:
  We demonstrate a new class of hollow-core Bragg fibers that are composed of
concentric cylindrical silica rings separated by nanoscale support bridges. We
theoretically predict and experimentally observe hollow-core confinement over
an octave frequency range. The bandwidth of bandgap guiding in this new class
of Bragg fibers exceeds that of other hollow-core fibers reported in the
literature. With only three rings of silica cladding layers, these Bragg fibers
achieve propagation loss of the order of 1 dB/m.


title: Fractional diffusion modeling of ion channel gating

abstract:
  An anomalous diffusion model for ion channel gating is put forward. This
scheme is able to describe non-exponential, power-law like distributions of
residence time intervals in several types of ion channels. Our method presents
a generalization of the discrete diffusion model by Millhauser, Salpeter and
Oswald [Proc. Natl. Acad. Sci. USA 85, 1503 (1988)] to the case of a
continuous, anomalous slow conformational diffusion. The corresponding
generalization is derived from a continuous time random walk composed of
nearest neighbor jumps which in the scaling limit results in a fractional
diffusion equation. The studied model contains three parameters only: the mean
residence time, a characteristic time of conformational diffusion, and the
index of subdiffusion. A tractable analytical expression for the characteristic
function of the residence time distribution is obtained. In the limiting case
of normal diffusion, our prior findings [Proc. Natl. Acad. Sci. USA 99, 3552
(2002)] are reproduced. Depending on the chosen parameters, the fractional
diffusion model exhibits a very rich behavior of the residence time
distribution with different characteristic time-regimes. Moreover, the
corresponding autocorrelation function of conductance fluctuations displays
nontrivial features. Our theoretical model is in good agreement with
experimental data for large conductance potassium ion channels.


title:
Global minima of Al_N, Au_N and Pt_N, N=2-80, clusters described by
  Voter-Chen version of embedded-atom potentials

abstract:
  Using the basin-hopping Monte Carlo minimization approach we report the
global minima for aluminium, gold and platinum metal clusters modelled by the
Voter-Chen version of the embedded-atom model potential containing up to 80
atoms. The virtue of the Voter-Chen potentials is that they are derived by
fitting to experimental data of both diatomic molecules and bulk metals
simultaneously. Therefore, it may be more appropriate for a wide range of the
size of the clusters. This is important since almost all properties of the
small clusters are size dependent. The results show that the global minima of
the Al, Au and Pt clusters have structures based on either octahedral,
decahedral, icosahedral or a mixture of decahedral and icosahedral packing. The
54-atom icosahedron without a central atom is found to be more stable than the
55-atom complete icosahedron for all of the elements considered in this work.
The most of the Al global minima are identified as some fcc structures and many
of the Au global minima are found to be some low symmetric structures, which
are both in agreement with the previous experimental studies.


title:
The conversion of nonlocal one-body operators into local ones: The
  Slater potential revisited

abstract:
  One-particle Schrodinger equations are considered, e.g., the Hartree--Fock
equations, that contain a nonlocal operator, e.g., the Hartree--Fock exchange
operator, where this operator depends on the one-particle density-matrix of a
determinantal state. One-body nonlocal operators of this type are converted
into approximate local potentials that depend on the kernel of the nonlocal
operator and, also, the one-particle density matrix that, as mentioned above,
the nonlocal operator also depends on. When the non-local operator is the
exchange operator, the method yields the Slater potential.


title: On the possible discovery of precessional effects in ancient astronomy

abstract:
  The possible discovery of astronomical effects due to precession - such as
the shift in the declination of heliacal raising of bright stars or the
precession of the equinoxes - is reviewed for various ancient cultures in the
world. Although definitive evidence of the discovery is still lacking, the
quantity of hints (for instance, coming from ancient Egypt) is impressive and
stimulating in view of further research.


title:
Photoassociation spectroscopy of cold alkaline earth atoms near the
  intercombination line

abstract:
  The properties of photoassociation (PA) spectra near the intercombination
line (the weak transition between $^{1}S_{0}$ and $^{3}P_{1}$ states) of group
II atoms are theoretically investigated. As an example we have carried out a
calculation for Calcium atoms colliding at ultra low temperatures of 1 mK, 1
$\mu$K, and 1 nK. Unlike in most current photoassociation spectroscopy the
Doppler effect can significantly affect the shape of the investigated lines.
Spectra are obtained using Ca--Ca and Ca--Ca$^*$ short-range {\it ab initio}
potentials and long-range van der Waals and resonance dipole potentials. The
similar van der Waals coefficients of ground $^{1}S_{0} + ^{1}S_{0}$ and
excited $^{1}S_{0} + ^{3}P_{1}$ states cause the PA to differ greatly from
those of strong, allowed transitions with resonant dipole interactions. The
density of spectral lines is lower, the Condon points are at relatively short
range, and the reflection approximation for the Franck-Condon factors is not
applicable, and the spontaneous decay to bound ground-state molecules is
efficient. Finally, the possibility of efficient production of cold molecules
is discussed.


title: Dynamics of the Pionium with the Density Matrix Formalism

abstract:
  The evolution of pionium, the $\pi^+ \pi^-$ hydrogen-like atom, while passing
through matter is solved within the density matrix formalism in the first Born
approximation. We compare the influence on the pionium break-up probability
between the standard probabilistic calculations and the more precise picture of
the density matrix formalism accounting for interference effects. We focus our
general result in the particular conditions of the DIRAC experiment at CERN.


title: Vortex Tubes in Turbulence Velocity Fields at Reynolds Numbers 300-1300

abstract:
  The most elementary structures of turbulence, i.e., vortex tubes, are studied
using velocity data obtained in a laboratory experiment for boundary layers
with microscale Reynolds numbers 295-1258. We conduct conditional averaging for
enhancements of a small-scale velocity increment and obtain the typical
velocity profile for vortex tubes. Their radii are of the order of the
Kolmogorov length. Their circulation velocities are of the order of the
root-mean-square velocity fluctuation. We also obtain the distribution of the
interval between successive enhancements of the velocity increment as the
measure of the spatial distribution of vortex tubes. They tend to cluster
together below about the integral length and more significantly below about the
Taylor microscale. These properties are independent of the Reynolds number and
are hence expected to be universal.


title:
Optimizing the photoassociation of cold atoms by use of chirped laser
  pulses

abstract:
  Photoassociation of ultracold atoms induced by chirped picosecond pulses is
analyzed in a non-perturbative treatment by following the wavepackets dynamics
on the ground and excited surfaces. The initial state is described by a
Boltzmann distribution of continuum scattering states. The chosen example is
photoassociation of cesium atoms at temperature T=54 $\mu K$ from the $a^3
\Sigma_u^+(6s,6s)$ continuum to bound levels in the external well of the
$0_g^-(6s+6p_{3/2})$ potential. We study how the modification of the pulse
characteristics (carrier frequency, duration, linear chirp rate and intensity)
can enhance the number of photoassociated molecules and suggest ways of
optimizing the production of stable molecules.


title: Titan's Atomic and Molecular Nitrogen Tori

abstract:
  Shematovich et al. (2003) recently showed plasma induced sputtering in
Titan's atmosphere is a source of neutral nitrogen in Saturn's magnetosphere
comparable to the photo-dissociation source. These sources form a toroidal
nitrogen cloud roughly centered at Titan's orbital radius but gravitationally
bound to Saturn. Once ionized, these particles contribute to Saturn's plasma.
When Titan is inside Saturn's magnetopause, newly formed ions can diffuse
inward becoming inner magnetospheric energetic nitrogen where they can sputter
and be implanted into icy satellite surfaces. Our 3-D simulation produces the
first consistent Titan generated N and N2 neutral clouds; solar UV radiation
and magnetospheric plasma subject these particles to dissociation and
ionization. The cloud morphologies and associated nitrogen plasma source rates
are predicted in anticipation of Cassini data. Since the amount of molecular
nitrogen ejected from Titan by photo-dissociation is small, molecular nitrogen
ions detection by Cassini will be an indicator of atmospheric sputtering.


title:
Fine Structure of the 1s3p ^3P_J Level in Atomic ^4He: Theory and
  Experiment

abstract:
  We report on a theoretical calculation and a new experimental determination
of the 1s3p ^3P_J fine structure intervals in atomic ^4He. The values from the
theoretical calculation of 8113.730(6) MHz and 658.801(6) MHz for the nu_{01}
and nu_{12} intervals, respectively, disagree significantly with previous
experimental results. However, the new laser spectroscopic measurement reported
here yields values of 8113.714(28) MHz and 658.810(18) MHz for these intervals.
These results show an excellent agreement with the theoretical values and
resolve the apparent discrepancy between theory and experiment.


title:
Statistical evaporation of rotating clusters. IV. Alignment effects in
  the dissociation of nonspherical clusters

abstract:
  Unimolecular evaporation in rotating, non-spherical atomic clusters is
investigated using Phase Space Theory in its orbiting transition state version.
The distributions of the total kinetic energy release epsilon_tr and the
rotational angular momentum J_r are calculated for oblate top and prolate top
main products with an arbitrary degree of deformation. The orientation of the
angular momentum of the product cluster with respect to the cluster symmetry
axis has also been obtained. This statistical approach is tested in the case of
the small 8-atom Lennard-Jones cluster, for which comparison with extensive
molecular dynamics simulations is presented. The role of the cluster shape has
been systematically studied for larger, model clusters in the harmonic
approximation for the vibrational densities of states. We find that the type of
deformation (prolate vs. oblate) plays little role on the distributions and
averages of epsilon_tr and J_r except at low initial angular momentum. However,
alignment effects between the product angular momentum and the symmetry axis
are found to be significant, and maximum at some degree of oblateness. The
effects of deformation on the rotational cooling and heating effects are also
illustrated.


title: Deceleration and electrostatic trapping of OH radicals

abstract:
  A pulsed beam of ground state OH radicals is slowed down using a Stark
decelerator and is subsequently loaded into an electrostatic trap.
Characterization of the molecular beam production, deceleration and trap
loading process is performed via laser induced fluorescence detection inside
the quadrupole trap. Depending on details of the trap loading sequence,
typically $10^5$ OH ($X^2\Pi_{3/2}, J=3/2$) radicals are trapped at a density
of around $10^7$ cm$^{-3}$ and at temperatures in the 50-500 mK range. The 1/e
trap lifetime is around 1.0 second.


title:
Application of Relativistic Coupled-cluster Theory to Heavy Atomic
  Systems with Strongly Interacting Configurations: Hyperfine Interactions in
  $^{207}Pb^+$

abstract:
  This work presents a first time accurate calculation of the magnetic dipole
hyperfine structure constants for the ground state and some low-lying excited
states of Pb$^+$. By comparing different levels of approximation with
experimental results, we demonstrate the importance of correlation effects
which reach beyond lower order relativistic many body perturbation theory.
Employing relativistic coupled-cluster theory we obtain a quantitative
understanding of the core-polarization and correlation effects inherent in this
system and observe completely different trends compared to $Ba^+$.


title:
Schottky-Enabled Photoemission in a RF Accelerator Photoinjector -
  Possible Generation of Ultra-Low Transverse Thermal Emittance Electron Beam

abstract:
  We present a clear signature of the Schottky effect in a RF photoinjector
using photons with energy lower than the Mg cathode work function. This
signature is manifested by the shift in the RF phase angle for the onset of the
detection of photoelectrons via single-photon absorption and allows for a
reasonable estimate of the field enhancement factor. This is a viable method to
generate an electron beam with very low thermal emittance and thus, a high
brightness beam.


title: Stacked clusters of polycyclic aromatic hydrocarbon molecules

abstract:
  Clusters of polycyclic aromatic hydrocarbon (PAH) molecules are modelled
using explicit all-atom potentials using a rigid body approximation. The PAH's
considered range from pyrene (C10H8) to circumcoronene (C54H18), and clusters
containing between 2 and 32 molecules are investigated. In addition to the
usual repulsion-dispersion interactions, electrostatic point-charge
interactions are incorporated, as obtained from density functional theory
calculations. The general electrostatic distribution in neutral or singly
charged PAH's is reproduced well using a fluctuating charges analysis, which
provides an adequate description of the multipolar distribution. Global
optimization is performed using a variety of methods, including basin-hopping
and parallel tempering Monte Carlo. We find evidence that stacking the PAH
molecules generally yields the most stable motif. A structural transition
between one-dimensional stacks and three-dimensional shapes built from mutiple
stacks is observed at larger sizes, and the threshold for this transition
increases with the size of the monomer. Larger aggregates seem to evolve toward
the packing observed for benzene in bulk.Difficulties met in optimizing these
clusters are analysed in terms of the strong anisotropy of the molecules. We
also discuss segregation in heterogeneous clusters and vibrational properties
in the context of astrophysical observations.


title:
A DAQ System for Linear Collider TPC Prototypes based on the ALEPH TPC
  Electronics

abstract:
  Within the international studies of a high energy linear electron positron
collider, several groups are developing and testing prototypes for a Linear
Collider TPC. This detector is planned to be used as a central part in the
tracking system of a detector at such a machine. In this note we describe a DAQ
system, which has been developed for the use in tests of TPC prototypes. It is
based on electronics used at the ALEPH experiment at CERN.


title:
Where To Go and How To Go: a Theoretical Study of Different Leader Roles
  in Networked Systems

abstract:
  This letter studies synchronization conditions for distributed dynamic
networks with different types of leaders. The role of a leader specifying a
desired global state trajectory through local interactions (the power leader)
has long been recognized and modeled. This paper introduces the complementary
notion of a knowledge leader holding information on the target dynamics, which
is propagated to the entire network through local adaptation mechanisms.
Knowledge-based leader-followers networks have many analogs in biology, e.g.,
in evolutionary processes and disease propagation. Different types of leaders
can co-exist in the same network.


title: UV spectra of benzene isotopomers and dimers in helium nanodroplets

abstract:
  We report spectra of various benzene isotopomers and their dimers in helium
nanodroplets in the region of the first Herzberg-Teller allowed vibronic
transition 610 1B2u<-1A1g (the A00 transition) at ~260 nm. Excitation spectra
have been recorded using both beam depletion detection and laser-induced
fluorescence. Unlike for many larger aromatic molecules, the monomer spectra
consist of a single "zero-phonon" line, blueshifted by ~30 cm-1 from the gas
phase position. Rotational band simulations show that the moments of inertia of
C6H6 in the nanodroplets are at least 6 times larger than in the gas phase. The
dimer spectra present the same vibronic fine structure (though modestly
compressed) as previously observed in the gas phase. The fluorescence lifetime
and quantum yield of the dimer are found to be equal to those of the monomer,
implying substantial inhibition of excimer formation in the dimer in helium.


title: Relativistic and QED corrections to the g factor of Li-like ions

abstract:
  Calculations of various corrections to the g factor of Li-like ions are
presented, which result in a significant improvement of the theoretical
accuracy in the region Z = 6-92. The configuration-interaction Dirac-Fock
method is employed for the evaluation of the interelectronic-interaction
correction of order 1/Z^2 and higher. This correction is combined with the 1/Z
interelectronic-interaction term derived within a rigorous QED approach. The
one-electron QED corrections of first in \alpha are calculated to all orders in
the parameter \alpha Z. The screening of QED corrections is taken into account
to the leading orders in \alpha Z and 1/Z.


title:
Cosmic Rays and Solar Insolation as the Main Control Parameters of the
  Catastrophe Theory of Climatic Response to Orbital Variations

abstract:
  The energy-balance model of global climate, which is taking into account a
nontrivial role of solar and galactic protons, is presented. The model is
described by the equation of fold catastrophe relative to increment of
temperature, where the variation of a solar insolation and cosmic rays are
control parameters. It is shown that the bifurcation equation of the model
describes one of two stable states of the climate system. The solution of this
equation exhibits the property of the determined bistable behavior of climate
at the global level and the possibility of appearance of the determined chaos
of "the weathers" at the local levels. The results of the comparative analysis
of the computer simulation of the time-dependent solution of energy-balance
model of global climate and the oxygen isotope records for deep-sea core
V28-238 over the past 730 kyr are presented, and the evolution of climate on
100 kyr forward is also predicted. It is shown that the proposed model
successfully explains the nicety of the paleoclimatic records. The model is
clear of all known difficulties of the Milankovich theory for the analysis and
the interpretation of physical mechanism, by which the climate system responds
to orbital forcing.


title:
AC Stark shift noise in QND measurement arising from quantum
  fluctuations of light polarization

abstract:
  In a recent letter [Auzinsh {\it{et. al.}} (physics/0403097)] we have
analyzed the noise properties of an idealized atomic magnetometer that utilizes
spin squeezing induced by a continuous quantum nondemolition measurement. Such
a magnetometer measures spin precession of $N$ atomic spins by detecting
optical rotation of far-detuned probe light. Here we consider maximally
squeezed probe light, and carry out a detailed derivation of the contribution
to the noise in a magnetometric measurement due to the differential AC Stark
shift between Zeeman sublevels arising from quantum fluctuations of the probe
polarization.


title: Tangent planes and the mean-field approximation

abstract:
  Local linearization is highlighted to explain the success of the orbital
approximation in positive response to Scerri's comments on the electronic
configuration model. The relevance of Rydberg states is made clear.


title: Engineering of directional emission from photonic crystal waveguides

abstract:
  We analyze, by the finite-difference time-domain numerical methods, several
ways to enhance the directional emission from photonic crystal waveguides
through the beaming effect recently predicted by Moreno et al. [Phys. Rev. E
69, 121402(R) (2004)], by engineering the surface modes and corrugation of the
photonic crystal surface. We demonstrate that the substantial enhancement of
the light emission can be achieved by increasing the refractive index of the
surface layer. We also measure power of surface modes and reflected power and
confirm that the enhancement of the directional emission is related to the
manipulation of the photonic crystal surface modes.


title:
Frozen Waves: Stationary optical wavefields with arbitrary longitudinal
  shape, by superposing equal-frequency Bessel beams

abstract:
  In this paper it is shown how one can use Bessel beams to obtain a stationary
localized wavefield with high transverse localization, and whose longitudinal
intensity pattern can assume any desired shape within a chosen interval 0 < z <
L of the propagation axis. This intensity envelope remains static, i.e., with
velocity v=0; and because of this we call "Frozen Waves" such news solutions to
the wave equations (and, in particular, to the Maxwell equations). These
solutions can be used in many different and interesting applications, as
optical tweezers, atom guides, optical or acoustic bistouries, various
important medical purposes, etc.


title: Theory of electrical conductivities of ferrogels

abstract:
  Conductive organic polymers can be formulated with polymers that incorporate
fine dispersed metallic particles.
  In this work, we present a general model for ferrogels which are chemically
cross-linked polymer networks swollen with a ferrofluid. Our aim is to study
the effect of the shape and/or material (conductivity) anisotropy on the
effective electrical conductivity of the ferrogel in the presence of an
external magnetic field. Our theory can reproduce the known results, and
provides a link between the particle property and orientation distribution and
the effective electrical conductivity. To this end, we find that material
(conductivity) anisotropies are more important to yield a high effective
electrical conductivity than shape anisotropies, while magnetic fields can
offer a correction.


title: Second-harmonic generation in graded metallic films

abstract:
  We study the effective second-harmonic generation (SHG) susceptibility in
graded metallic films by invoking the local field effects exactly, and further
numerically demonstrate that the graded metallic films can serve as a novel
optical material for producing a broad structure in both the linear and SHG
response and an enhancement in the SHG signal.


title:
Statistical-mechanical theory of the overall magnetic properties of
  mesocrystals

abstract:
  The mesocrystal showing both electrorheological and magnetorheological
effects is called electro-magnetorheological (EMR) solids. Prediction of the
overall magnetic properties of the EMR solids is a challenging task due to the
coexistence of the uniaxially anisotropic behavior and structural transition as
well as long-range interaction between the suspended particles. To consider the
uniaxial anisotropy effect, we present an anisotropic Kirkwood-Fr\"{o}hlich
equation for calculating the effective permeabilities by adopting an explicit
characteristic spheroid rather than a characteristic sphere used in the
derivation of the usual Kirkwood-Fr\"{o}hlich equation. Further, by applying an
Ewald-Kornfeld formulation we are able to investigate the effective
permeability by including the structural transition and long-range interaction
explicitly. Our theory can reduce to the usual Kirkwood-Fr\"{o}hlich equation
and Onsager equation naturally. To this end, the numerical simulation shows the
validity of monitoring the structure of EMR solids by detecting their effective
permeabilities.


title: Nonlinear ac responses of electro-magnetorheological fluids

abstract:
  We apply a Langevin model to investigate the nonlinear ac responses of
electro-magnetorheological (ERMR) fluids under the application of two crossed
dc magnetic (z axis) and electric (x axis) fields and a probing ac sinusoidal
magnetic field. We focus on the influence of the magnetic fields which can
yield nonlinear behaviors inside the system due to the particles with a
permanent magnetic dipole moment.
  Based on a perturbation approach, we extract the harmonics of the magnetic
field and orientational magnetization analytically. To this end, we find that
the harmonics are sensitive to the degree of anisotropy of the structure as
well as the field frequency. Thus, it is possible to real-time monitor the
structure transformation of ERMR fluids by detecting the nonlinear ac
responses.


title:
The Dynamical Velocity Superposition Effect in the Quantum-Foam In-Flow
  Theory of Gravity

abstract:
  The new `quantum-foam in-flow' theory of gravity has explained numerous
so-called gravitational anomalies, particularly the `dark matter' effect which
is now seen to be a dynamical effect of space itself, and whose strength is
determined by the fine structure constant, and not by Newton's gravitational
constant G. Here we show an experimentally significant approximate dynamical
effect, namely a vector superposition effect which arises under certain
dynamical conditions when we have absolute motion and gravitational in-flows:
the velocities for these processes are shown to be approximately vectorially
additive under these conditions. This effect plays a key role in interpreting
the data from the numerous experiments that detected the absolute linear motion
of the earth. The violations of this superposition effect lead to observable
effects, such as the generation of turbulence. The flow theory also leads to
vorticity effects that the Gravity Probe B gyroscope experiment will soon begin
observing. As previously reported General Relativity predicts a smaller
vorticity effect (therein called the Lense-Thirring `frame-dragging' effect)
than the new theory of gravity.


title: On the origin of the notion of GW et cetera

abstract:
  The notion of gravitational wave (GW) came forth originally as a by-product
of the linear approximation of general relativity (GR). Now, it can be proved
that this approximation is quite inadequate to a proper study of the hypothetic
GW's. The significant role of the approximations beyond the linear stage is
emphasized.


title: Dark resonances as a probe for the motional state of a single ion

abstract:
  Single, rf-trapped ions find various applications ranging from metrology to
quantum computation. High-resolution interrogation of an extremely weak
transition under best observation conditions requires an ion almost at rest. To
avoid line-broadening effects such as the second order Doppler effect or rf
heating in the absence of laser cooling, excess micromotion has to be
eliminated as far as possible. In this work the motional state of a confined
three-level ion is probed, taking advantage of the high sensitivity of observed
dark resonances to the trapped ion's velocity. Excess micromotion is controlled
by monitoring the dark resonance contrast with varying laser beam geometry. The
influence of different parameters such as the cooling laser intensity has been
investigated experimentally and numerically.


title:
Generalized Stress Concentration Factors for Equilibrated Forces and
  Stresses

abstract:
  As a sequel to a recent work we consider the generalized stress concentration
factor, a purely geometric property of a body that for the various external
loading fields indicates the worst ratio between the maximum of the optimal
stress and maximum of the external loading. The optimal stress concentration
factor pertains to a stress field that satisfies the principle of virtual work
and for which the stress concentration factor is minimal. Unlike the previous
work, we require that the external loading be equilibrated and that the stress
field be a symmetric tensor field.


title: Citation Statistics From More Than a Century of Physical Review

abstract:
  We study the statistics of citations from all Physical Review journals for
the 110-year period 1893 until 2003. In addition to characterizing the citation
distribution and identifying publications with the highest citation impact, we
investigate how citations evolve with time. There is a positive correlation
between the number of citations to a paper and the average age of citations.
Citations from a publication have an exponentially decaying age distribution;
that is, old papers tend to not get cited. In contrast, the citations to a
publication are consistent with a power-law age distribution, with an exponent
close to -1 over a time range of 2 -- 20 years. We also identify a number of
strongly-correlated citation bursts and other dramatic features in the time
history of citations to individual publications.


title: Absorption Imaging and Spectroscopy of Ultracold Neutral Plasmas

abstract:
  Absorption imaging and spectroscopy can probe the dynamics of an ultracold
neutral plasma during the first few microseconds after its creation.
Quantitative analysis of the data, however, is complicated by the inhomogeneous
density distribution, expansion of the plasma, and possible lack of global
thermal equilibrium for the ions. In this article we describe methods for
addressing these issues. Using simple assumptions about the underlying
temperature distribution and ion motion, the Doppler-broadened absorption
spectrum obtained from plasma images can be related to the average temperature
in the plasma.


title: An Alternative Approach to Explaining Magnetospheric Processes

abstract:
  This paper gives a brief outline of the progression from the first substorm
model developed in [Ponomarev, 1985; Sedykh, Ponomarev, 2002] based on C.F.
Kennel's ideas, to the present views about the mechanism by which solar wind
kinetic energy is converted to electromagnetic energy at the Bow Shock and by
which this energy is transferred to the magnetosphere in the form of current;
about the transformation of the energy of this current to gas kinetic energy of
convecting plasma tubes, and, finally, the back transformation of gas kinetic
energy to electromagnetic energy in secondary magnetospheric MHD generators.
The questions of the formation of the magnetospheric convection system, the
nature of substorm break-up, and of the matching of currents in the
magnetosphere-ionosphere system are discussed.


title: Scaling and Formulary cross sections for ion-atom impact ionization

abstract:
  The values of ion-atom ionization cross sections are frequently needed for
many applications that utilize the propagation of fast ions through matter.
When experimental data and theoretical calculations are not available,
approximate formulas are frequently used. This paper briefly summarizes the
most important theoretical results and approaches to cross section calculations
in order to place the discussion in historical perspective and offer a concise
introduction to the topic. Based on experimental data and theoretical
predictions, a new fit for ionization cross sections is proposed. The range of
validity and accuracy of several frequently used approximations (classical
trajectory, the Born approximation, and so forth) are discussed using, as
examples, the ionization cross sections of hydrogen and helium atoms by various
fully stripped ions.


title:
Atomic Clocks and the Search for Variation of the Fine Structure
  Constant

abstract:
  Evidence that the fine structure constant, alpha, was different in an early
epoch has recently been found in quasar (QSO) absorption spectra. An accurate
laboratory measurement of alpha variation could help to distinguish between
space and time variation of alpha and possibly confirm the QSO results. We have
performed calculations of the relativistic energy shifts that a variation of
alpha would cause in a wide range of atomic spectra. A laboratory measurement
of how these transition frequencies vary over time is vital in determining
whether alpha is varying today.


title:
The resonant behaviour of the Faraday rotation in a medium with linear
  birefringence

abstract:
  It is shown that the monochromatic optical wave propagating through the
medium with linear birefringence in presence of a signal electromagnetic wave
(whose wavelength is equal to the polarization beats length), displays Faraday
rotation having the frequency of the signal wave and unsuppressed by linear
birefringence. The effect is resonant with respect to the frequency of a signal
wave. The "sharpness" of the resonance is defined by length of the birefringent
medium.


title:
Computation of a homogeneous coordinate time series for European GPS
  stations by reprocessing of the weekly EPN solutions

abstract:
  Weekly coordinate time series for the all EPN (European Permanent GPS
Network) stations for the period of observations beginning from GPS week 834
was obtained by a reprocessing of the official EPN solutions. Comparison of
this series with EPN Central Bureau (EPN CB) and the previous IAA two-year
solution for selected EPN stations obtained by reprocessing of the original
observations is performed. Results of comparison show that new solution based
on fiducial-free strategy is most likely free of seasonal errors. Now the new
IAA EPN solution is being computed regularly (on availability of the official
EPN solution) and is available to any interested group.


title:
Optic-Mechanical Analogy and Gravitational Effects in the Extended Space
  Model

abstract:
  New approach to the description of a gravitation using analogy between the
optical and mechanical phenomenon is advanced. For this purpose in extended
(1+4)-dimensional space G(1,4) the gravitational effects are considered: the
speed of escape, red shift, radar echo, deviation light and perihelion
precession of Mercury. It is shown, that methods of the Extended Space Model
(ESM) give the same outcomes, as General Theory of Relativity (GR). The various
ways of introduction of refraction index are discussed, which appropriate to
the gravitational field.


title:
Statistics of the seasonal cycle of the 1951-2000 surface temperature
  records in Italy

abstract:
  We present an analysis of seasonal cycle of the last 50 years of records of
surface temperature in Italy. We consider two data sets which synthesize the
surface temperature fields of Northern and Southern Italy. Such data sets
consist of records of daily maximum and minimum temperature. We compute the
best estimate of the seasonal cycle of the variables considered by adopting the
cyclograms' technique. We observe that in general the minimum temperature cycle
lags behind the maximum temperature cycle, and that the cycles of the Southern
Italy temperatures records lag behind the corresponding cycles referring to
Northern Italy. All seasonal cycles lag considerably behind the solar cycle.
The amplitude and phase of the seasonal cycles do not show any statistically
significant trend in the time interval considered.

categories: physics.ao-ph physics.data-an physics.geo-ph physics.soc-ph


title: Geometric Phase From Dielectric Matrix

abstract:
  The dielectric property $(2\times2)$ of the anisotropic optical medium is
found out considering the polarized photon as two component spinor of spherical
harmonics.The Geometric Phase of single polarized photon has been evaluated in
two ways. The phase two-form of the dielectric matrix through a twist and the
Pancharatnam phase (GP) through the change of angular momentum of the incident
polarized photon over a closed triangular path on the extended Poincare sphere.
The helicity in connection with the spin angular momentum of the chiral photon
plays the key role in developing these phase holonomies.


title:
Destabilization of the thermohaline circulation by transient
  perturbations to the hydrological cycle

abstract:
  We reconsider the problem of the stability of the thermohaline circulation as
described by a two-dimensional Boussinesq model with mixed boundary conditions.
We determine how the stability properties of the system depend on the intensity
of the hydrological cycle. We define a two-dimensional parameters' space
descriptive of the hydrology of the system and determine, by considering
suitable quasi-static perturbations, a bounded region where multiple equilibria
of the system are realized. We then focus on how the response of the system to
finite-amplitude surface freshwater forcings depends on their rate of increase.
We show that it is possible to define a robust separation between slow and fast
regimes of forcing. Such separation is obtained by singling out an estimate of
the critical growth rate for the anomalous forcing, which can be related to the
characteristic advective time scale of the system.

categories: physics.ao-ph physics.comp-ph physics.flu-dyn physics.geo-ph


title:
Geminate recombination of electrons generated by above-the-gap (12.4 eV)
  photoionization of liquid water

abstract:
  The picosecond geminate recombination kinetics for hydrated electrons
generated by 200 nm two photon absorption (12.4 eV total energy) has been
measured in both light and heavy water. The geminate kinetics are observed to
be almost identical in both H2O and D2O. Kinetic analysis based upon the
independent reaction time approximation indicates that the average separation
between the electron and its geminate partners in D2O is 13% narrower than in
H2O (2.1 nm vs. 2.4 nm). These observations suggest that, even at this high
ionization energy, autoionization of water competes with direct ionization.


title:
Observation of Vertical Betatron Sideband due to Electron Clouds in the
  KEKB LER

abstract:
  The effects of electron clouds on positively-charged beams have been an
active area of research in recent years at particle accelerators around the
world. Transverse beam-size blow-up due to electron clouds has been observed in
some machines, and is considered to be a major limiting factor in the
development of higher-current, higher-luminosity electron-positron colliders.
The leading proposed mechanism for beam blow-up is the excitation of a fast
head-tail instability due to short-range wakes within the electron cloud. We
present here observations of betatron oscillation sidebands in bunch-by-bunch
spectra that may provide direct evidence of such head-tail motion in a positron
beam.


title: Laboratory Physics and Cosmology

abstract:
  We find five fundamental reasons demanding that any gravitational mass m, and
the speed of light c, vary with cosmological time such that mc remains
constant. This is required by the universal condition of conservation of
momentum in a Universe with spatial homogeneity. We prove that this is
consistent with Einstein's Theory of General Relativity. We call this effect a
"MASS BOOM". At the LAB system no such time variations can be detected, unless
we make comparisons with cosmological observations. We have to stress that the
physical conditions implied by a time varying mass, together with a time
varying speed of light, preserving the constancy of momentum, are compatible
with Einstein's field equations. We then integrate his cosmological equations
and find the solution for the cosmological scale factor a(t) proportional to
the square of time, implying an apparent accelerated expansion for the
Universe, as seen from the LAB frame. This is the interpretation given to
recent observations obtained from the Supernova Type Ia. This determination of
the scale factor a(t) is based upon a LAB interpretation and therefore is an
apparent effect. On the other hand we note that the product ct being a constant
determines the real Universe as a static one, of constant size. The observed
red shift at the LAB system is due to a real shrinkage of the quantum world,
due to the decrease in size of the quantum particles determined by a decreasing
Planck's "constant".


title: Harmonic generation in a two dimensional nonlinear quasicrystal

abstract:
  Second harmonic generation in a two dimensional nonlinear quasi-crystal is
demonstrated for the first time. Temperature and wavelength tuning of the
crystal reveal the uniformity of the pattern while angle tuning reveals the
dense nature of the crystal's Fourier spectrum. These results compare well with
theoretical predictions showing the excellent uniformity of the crystal and
suggest that more complicated ``nonlinear holograms'' should be possible.


title: PC Cluster Machine Equipped with Low-Latency Communication Software

abstract:
  A high performance Beowulf (PC cluster) machine installed with Linux
operating system and MPI (Message Passing Interface) for interprocessor
communications has been constructed using Gigabit Ethernet and the
communication software GAMMA (Genoa Active Message Machine), instead of the
standard TCP/IP protocol. Fast C/Fortran compilers have been exploited with the
GAMMA communication libraries. This method has eliminated large communication
overhead of TCP/IP and resulted in significant increase in the computational
performance of real application programs including the first-principle
molecular dynamics simulation code. Scalability on the number of processors and
reliability over a long period of time (days) have also been confirmed for the
GAMMA communications.
  Keywords: non TCP/IP, active messages, small latency, fast C/Fortran
compilers, first-principle (quantum mechanical) molecular dynamics, advanced
materials


title: A New Free Core Nutation Model with Variable Amplitude and Period

abstract:
  Three most long and dense VLBI nutation series obtained at the Goddard Space
Flight Center, Institute of Applied Astronomy, and U.S. Naval Observatory were
used for investigation of the Free Core Nutation (FCN) contribution to the
celestial pole offset. Some recent studies have showed that the FCN period
or/and phase does not remain constant, but varies in a rather wide range of
about 410--490 days (for equivalent period). To implement this result in the
practice, a new FCN model with variable amplitude and period (phase) is
developed. Comparison of this model with observations shows better agreement
than existing one. After correction of the differences between observed VLBI
nutation series and the IAU2000A model, they decreased to a level about 100
microarcseconds.


title: A Scaling Approach to Ideal Quantum Gases

abstract:
  The thermodynamic properties of ideal quantum gases are derived solely from
dimensional arguments, the Pauli principle and thermodynamic relations, without
resorting to statistical mechanics.

categories: physics.ed-ph cond-mat.stat-mech physics.gen-ph quant-ph


title:
Weibel instability on weakly relativistic produced plasma by circular
  polarization microwave electric field

abstract:
  The production of weakly relativistic plasma by microwave electric field with
circular polarization has been studied. Electron distribution function obtained
for this produced plasma and shown that it is non-equilibrium and anisotropic.
It is shown that produced plasma accelerated on direction of propagation
microwave electric field. The electron velocity on this direction strongly
depends on electron origination phase during ionization and microwave electric
field phase and it s amplitude. The dielectric tensor obtained for this plasma
and the weibel instability studied for it.


title: Enhancement of microcavity lifetimes using highly dispersive materials

abstract:
  We show analytically, and numerically that highly-dispersive media can be
used to drastically increase lifetimes of high-Q microresonators. In such a
resonator, lifetime is limited either by undesired coupling to radiation, or by
intrinsic absorption of the constituent materials. The presence of dispersion
weakens coupling to the undesired radiation modes and also effectively reduces
the material absorption.


title:
Integral analysis of laminar indirect free convection boundary layers
  with weak blowing for Schmidt no. ~ 1

abstract:
  Laminar natural convection at unity Schmidt number over a horizontal surface
with a weak normal velocity at the wall is studied using an integral analysis.
To characterise the strength of the blowing, we define a non-dimensional
parameter called the blowing parameter. After benchmarking with the no blowing
case, the effect of the blowing parameter on boundary layer thickness, velocity
and concentration profiles is obtained. Weak blowing is seen to increase the
wall shear stress. For blowing parameters greater than unity, the diffusional
flux at the wall becomes negligible and the flux is almost entirely due to the
blowing.