title:
High-precision Absolute Distance and Vibration Measurement using
  Frequency Scanned Interferometry

abstract:
  In this paper, we report high-precision absolute distance and vibration
measurements performed with frequency scanned interferometry using a pair of
single-mode optical fibers. Absolute distance was determined by counting the
interference fringes produced while scanning the laser frequency. A
high-finesse Fabry-Perot interferometer(F-P) was used to determine frequency
changes during scanning. Two multiple-distance-measurement analysis techniques
were developed to improve distance precision and to extract the amplitude and
frequency of vibrations. Under laboratory conditions, measurement precision of
$\sim$ 50 nm was achieved for absolute distances ranging from 0.1 meters to 0.7
meters by using the first multiple-distance-measurement technique. The second
analysis technique has the capability to measure vibration frequencies ranging
from 0.1 Hz to 100 Hz with amplitude as small as a few nanometers, without a
priori knowledge.


title:
Polaritonics in complex structures: Confinement, bandgap materials, and
  coherent control

abstract:
  We report on the design, fabrication, and testing of ferroelectric patterned
materials in the guided-wave and polaritonic regime. We demonstrate their
functionality and exploit polariton confinement for amplification and coherent
control using temporal pulse shaping.


title:
Multistability and memory effect in a highly turbulent flow:
  experimental evidence for a global bifurcation

abstract:
  We report an experimental evidence of a global bifurcation on a highly
turbulent von Karman flow. The mean flow presents multiple solutions: the
canonical symmetric solution becomes marginally unstable towards a flow which
breaks the basic symmetry of the driving apparatus even at very large Reynolds
number. The global bifurcation between these states is highly subcritical and
the system thus keeps a memory of its history. The transition recalls
low-dimension dynamical systems transitions and exhibits a very peculiar
statistics. We discuss the role of turbulence in two ways: the multiplicity of
hydrodynamical solutions and the effect of fluctuations on the nature of
transitions.


title:
Coordinate Conditions for a Uniformly Accelerated or Static Plane
  Symmetric Metric

abstract:
  The coordinate conditions for three exact solutions for the metric components
of a coordinate system with constant acceleration or of a static plane
symmetric gravitational field are presented. First, the coordinate condition
that the acceleration of light is constant is applied to the field equations to
derive the metric of a coordinate system of constant acceleration. Second, the
coordinate conditions required to produce the metrics of Rindler and Lass are
applied to the field equations to calculate the components of these two metrics
and the coordinate velocities and coordinate accelerations for light of these
two metrics are compared to the coordinate system of constant acceleration.


title:
Research and Development in Front-End Electronics for Future Linear
  Collider Detectors

abstract:
  To probe physics of interest a decade after the LHC begins to take data, the
Linear Collider will need to have the capability of performing precision
measurements of masses and couplings. We discuss the demands that this places
on its associated detectors, and the status of and plans for continued R&D in
front-end electronics that is necessary to meet these demands.


title: On Cremonian Dimensions Qualitatively Different from Time and Space

abstract:
  We examine a particular kind of six-dimensional Cremonian universe featuring
one dimension of space, three dimensions of time and other two dimensions that
can*not* be ranked as either time or space. One of these two, generated by a
one-parametric aggregate of (straight-)lines lying on a quadratic cone, is more
similar to the spatial dimension. The other, represented by a
singly-parametrical set of singular space quartic curves situated on a proper
ruled quadric surface, bears more resemblance to time. Yet, the two dimensions
differ profoundly from both time and space because, although being macroscopic,
they are not accessible to (detectable by) every Cremonian observer. This
toy-model thus demonstrates that there might exist extra-dimensions that need
not necessarily be compactified to remain unobservable.


title:
Peculiarities of Thermodynamic Simulation with the Method of Bound
  Affinity

abstract:
  Thermodynamic simulation of chemical and metallurgical systems is the only
method to predict their equilibrium composition and is the most important
application of chemical thermodynamics. The conventional strategy of simulation
is always to find the most probable composition of the system, corresponding to
thermodynamic equilibrium. Traditional simulation methods do not account for
interactions within the chemical system. The Method of Bound Affinity (MBA) is
based on the theory that explicitly takes into account interactions between
subsystems of a complex chemical system and leads sometimes to essential
differences in simulation results. This article discusses peculiarities of MBA
application, exemplified by results for a complex system with a set of
subsystems.


title:
The Inconstancy of the Fundamental Physical Constants: Computational
  Status

abstract:
  It is argued that the CODATA recommended values of the fundamental physical
constants could not be used as the reference data in searching the hypothetical
space-time variations of the fundamental physical constants. It is shown that
the CODATA data permanently suffers a loss of self-consistency of the released
data due to unjustified over-rounding of their estimates. The simple estimates
of the critical numbers of decimal digits that should be saved in the
independently rounded correlation coefficients, the average values and
uncertainties to save the self-consistency is obtained. The set of high level
quality requirements to the computerized presentation of the numerical data on
the jointly measured or estimated physical values are formulated. It is argued
(once again) that the common standard for presentation of the numerical values
of correlated quantities in publications and sites is urgently needed.


title:
The Proof that Maxwell Equations with the 3D E and B are not Covariant
  upon the Lorentz Transformations but upon the Standard Transformations. The
  New Lorentz Invariant Field Equations

abstract:
  In this paper the Lorentz transformations (LT) and the standard
transformations (ST) of the usual Maxwell equations (ME) with the
three-dimensional (3D) vectors of the electric and magnetic fields, E and B
respectively, are examined using both the geometric algebra and tensor
formalisms. Different 4D algebric objects are used to represent the usual
observer dependent and the new observer independent electric and magnetic
fields. It is found that the ST of the ME differ from their LT and consequently
that the ME with the 3D E and B are not covariant upon the LT but upon the ST.
The obtained results do not depend on the character of the 4D algebric objects
used to represent the electric and magnetic fields. The Lorentz invariant field
equations are presented with 1-vectors E and B, bivectors E_{Hv} and B_{Hv} and
the abstract tensors, the 4-vectors E^{a} and B^{a}. All these quantities are
defined without reference frames, i.e., as absolute quantities. When some basis
has been introduced, they are represented as coordinate-based geometric
quantities comprising both components and a basis. It is explicitly shown that
this geometric approach agrees with experiments, e.g., the Faraday disk, in all
relatively moving inertial frames of reference, which is not the case with the
usual approach with the 3D E and B and their ST.


title: Variational formulations of exact and reduced Vlasov-Maxwell equations

abstract:
  The foundations of gyrokinetic theory are reviewed with an emphasis on the
applications of Lagrangian and Hamiltonian methods used in the derivation of
nonlinear gyrokinetic Vlasov-Maxwell equations. These reduced dynamical
equations describe the turbulent evolution of low-frequency electromagnetic
fluctuations in nonuniform magnetized plasmas with arbitrary magnetic geometry.


title:
Characterization and Modeling of Non-Uniform Charge Collection in CVD
  Diamond Pixel Detectors

abstract:
  A pixel detector with a CVD diamond sensor has been studied in a 180 GeV/c
pion beam. The charge collection properties of the diamond sensor were studied
as a function of the track position, which was measured with a silicon
microstrip telescope. Non-uniformities were observed on a length scale
comparable to the diamond crystallites size. In some regions of the sensor, the
charge drift appears to have a component parallel to the sensor surface (i.e.,
normal to the applied electric field) resulting in systematic residuals between
the track position and the hits position as large as 40 $\mu$m. A numerical
simulation of the charge drift in polycrystalline diamond was developed to
compute the signal induced on the electrodes by the electrons and holes
released by the passing particles. The simulation takes into account the
crystallite structure, non-uniform trapping across the sensor, diffusion and
polarization effects. It is in qualitative agreement with the data. Additional
lateral electric field components result from the non-uniform trapping of
charges in the bulk. These provide a good explanation for the large residuals
observed.


title:
Three levels of understanding physical relativity: Galileo's relativity,
  Up-to-date Galileo's relativity and Einstein's relativity: A historical
  survey

abstract:
  We present a way of teaching Einstein's special relativity. It starts with
Galileo's relativity, the learners know from previous lectures. The lecture
underlines that we can have three transformation equations for the space-time
coordinates of the same event, which lead to absolute clock readings, time
intervals and lengths (Galileo's relativity), to absolute clock readings but to
relative time intervals and lengths (up-to-date Galileo transformations) and to
relative clock readings time intervals and lengths.


title:
Strongly Coupled Matter-Field and Non-Analytic Decay Rate of Dipole
  Molecules in a Waveguide

abstract:
  The decay rate $\gam$ of an excited dipole molecule inside a waveguide is
evaluated for the strongly coupled matter-field case near a cutoff frequency
$\ome_c$ without using perturbation analysis. Due to the singularity in the
density of photon states at the cutoff frequency, we find that $\gam$ depends
non-analytically on the coupling constant $\ggg$ as $\ggg^{4/3}$. In contrast
to the ordinary evaluation of $\gam$ which relies on the Fermi golden rule
(itself based on perturbation analysis), $\gam$ has an upper bound and does not
diverge at $\ome_c$ even if we assume perfect conductance in the waveguide
walls. As a result, again in contrast to the statement found in the literature,
the speed of emitted light from the molecule does not vanish at $\ome_c$ and is
proportional to $c\ggg^{2/3}$ which is on the order of $10^3 \sim 10^4$ m/s for
typical dipole molecules.


title:
On climate response to changes in the cosmic ray flux and radiative
  budget

abstract:
  We examine the results linking cosmic ray flux (CRF) variations to global
climate change. We then proceed to study various periods over which there are
estimates for the radiative forcing, temperature change and CRF variations
relative to today. These include the Phanerozoic as a whole, the Cretaceous,
the Eocene, the Last Glacial Maximum, the 20th century, as well as the 11-yr
solar cycle. This enables us to place quantitative limits on climate
sensitivity to both changes in the CRF, Phi_CR, and the radiative budget, F,
under equilibrium. Under the assumption that the CRF is indeed a climate
driver, we find that the sensitivity to CRF variations is consistently fitted
with mu := -Phi_0 (dT_global/ d Phi_CR) = 6.5 +/- 2.5 K (where Phi_0 is the CR
energy flux today). Additionally, the sensitivity to radiative forcing changes
is lambda := dT_global/ dF_0 = 0.35 +/- 0.09 K/(W/m^2), at the current
temperature, while its temperature derivative is negligible with d lambda /
dT_0 = 0.01 +/- 0.03 1/(W/m^2). If the observed CRF/climate link is ignored,
the best sensitivity obtained is lambda = 0.54 +/- 0.12 K/(W/m^2) and d lambda
/ dT_0 = -0.02 +/- 0.05 1/(W/m^2). The CRF/climate link therefore implies that
the increased solar luminosity and reduced CRF over the previous century should
have contributed a warming of 0.37+/-0.13 K, while the rest should be mainly
attributed to anthropogenic causes. Without any effect of cosmic rays, the
increase in solar luminosity would correspond to an increased temperature of
0.16+/-0.04 K.


title:
Bending of Light Near a Star and Gravitational Red/Blue Shift :
  Alternative Explanation Based on Refraction of Light

abstract:
  Many of the general-relativity-tests such as bending of light near a star and
gravitational red/blue shift are explained without general-relativity and
without Newtonian-approach. The author first casts doubts on both, the
Newtonian and the relativistic approach; and proposes a novel
alternative-explanation. The new alternative-explanation is based on
refraction-phenomenon of optics. It predicts that as the ray passes
through/near the stars atmospheric-medium, it bends due to
refraction-phenomenon towards star-core, like a ray bends while passing through
a prism or water-drop. A semi-empirical estimation of the atmospheric-height
and its refractive-index are made to find the refraction-results. The
refraction-based theory also suggests new explanation for gravitational
red/blue shift; it tells that frequency remains constant (as it is so in
refraction-phenomenon) and the red/blue shift is due to change in wavelength
due to change in velocity of light in the medium . Estimated results for
bending of light and the red/blue shift etc. with the new approach though agree
well with known values, but important thing is that the physics is quite
different. The proposed refraction-based theory proposes a new-look on
black-hole, suggesting that black-hole formation is critically due to
total-internal-reflection within atmosphere and subsequent absorption into the
star-core. Gravitational-lensing is explained as real refraction-lensing. The
present paper also suggests a possible-alternative and meaning to the curved
geometry of space-time, and indicates that the fabric of space-time which
warps(curves) around the mass is not the empty-vacuum but the
atmospheric-medium.


abstract:
  First observation of generation in the backward wave oscillator with a "grid"
diffraction grating and lasing of the volume FEL with a "grid" volume resonator
that is formed by a perodic set of metallic threads inside a rectangular
waveguide is considered.


title:
Surface plasma resonance in small rare gas clusters by mixing IR and VUV
  laser pulses

abstract:
  The ionization dynamics of a Xenon cluster with 40 atoms is analyzed under a
pum p probe scenario of laser pulses where an infrared laser pulse of 50 fs
length follows with a well defined time delay a VUV pulse of the same length
and peak intensity. The mechanism of resonant energy absorption due to the
coinc idence of the IR laser frequency with the frequency of collective motion
of quasi free electrons in the cluster is mapped out by varying the time delay
between the pulses.


title:
Probabilistic forecasting of temperature: comments on the Bayesian Model
  Averaging approach

abstract:
  A specific implementation of Bayesian model averaging has recently been
suggested as a method for the calibration of ensemble temperature forecasts. We
point out the similarities between this new approach and an earlier method
known as kernel regression. We also argue that the Bayesian model averaging
method (as applied) has a number of flaws that would result in forecasts with
suboptimally calibrated mean and uncertainty.


title: The Scaling of Maximum and Basal Metabolic Rates of Mammals and Birds

abstract:
  Allometric scaling is one of the most pervasive laws in biology. Its origin,
however, is still a matter of dispute. Recent studies have established that
maximum metabolic rate scales with an exponent larger than that found for basal
metabolism. This unpredicted result sets a challenge that can decide which of
the concurrent hypotheses is the correct theory. Here we show that both scaling
laws can be deduced from a single network model. Besides the 3/4-law for basal
metabolism, the model predicts that maximum metabolic rate scales as $M^{6/7}$,
maximum heart rate as $M^{-1/7}$, and muscular capillary density as $M^{-1/7}$,
in agreement with data.


title:
Interval estimation in the presence of nuisance parameters. 1. Bayesian
  approach

abstract:
  We address the common problem of calculating intervals in the presence of
systematic uncertainties. We aim to investigate several approaches, but here
describe just a Bayesian technique for setting upper limits. The particular
example we study is that of inferring the rate of a Poisson process when there
are uncertainties on the acceptance and the background. Limit calculating
software associated with this work is available in the form of C functions.


title:
3D etching profile evolution simulation using sparse field level set
  method

abstract:
  Level set method, introduced by Osher and Sethian [1], is a highly robust and
accurate computational technique for tracking of moving interfaces in etching,
deposition and photolithography processes. It originates from the idea to view
the moving front as a particular level set of a higher dimensional function, so
the topological merging and breaking, sharp gradients and cusps can form
naturally, and the effects of curvature can be easily incorporated. The
corresponding equations of motion for the propagating surfaces, which resemble
Hamilton-Jacobi equations with parabolic right-hand sides, can be solved using
methods for solving hyperbolic conservation laws, ensuring in that the way
correct entropy-satisfying solution [2]. In this paper we describe an
application of the sparse field method for solving level set equations in 3D
plasma etching simulations. Sparse field method itself, developed by Whitaker
[3] and broadly used in image processing community, is an alternative to the
usual combination of narrow band and fast marching procedures for the
computationally effective solving of level set equations. The obtained results
for convex and non-convex Hamiltonians show correct behavior of etching
profiles in simple model cases.


title: Particle-in-cell simulations of rf breakdown

abstract:
  Breakdown voltages of a capacitively coupled radio frequency argon discharge
at 27 MHz are studied. We use a one-dimensional electrostatic PIC code to
investigate the effect of changing the secondary emission properties of the
electrodes on the breakdown voltage, particularly at low pd values. Simulation
results are compared with the available experimental results and a satisfactory
agreement is found.


title:
Thermohaline circulation stability: a box model study - Part I:
  uncoupled model

abstract:
  A thorough analysis of the stability of the uncoupled Rooth interhemispheric
3-box model of thermohaline circulation (THC) is presented. The model consists
of a northern high latitudes box, a tropical box, and a southern high latitudes
box, which respectively correspond to the northern, tropical and southern
Atlantic ocean. We adopt restoring boundary conditions for the temperature
variables and flux boundary conditions for the salinity variables. We study how
the strength of THC changes when the system undergoes forcings that are
analogous to those of global warming conditions by applying to the equilibrium
state perturbations to the moisture and heat fluxes into the three boxes. In
each class of experiments, we determine, using suitably de- fined metrics, the
boundary dividing the set of forcing scenarios that lead the system to
equilibria characterized by a THC pattern similar to the present one, from
those that drive the system to equilibria with a reversed THC. Fast increases
in the moisture flux into the northern high-latitude box are more effective
than slow increases in leading the THC to a breakdown, while the increases of
moisture flux into the southern high-latitude box strongly inhibits the
breakdown and can prevent it, in the case of slow increases in the Northern
Hemisphere. High rates of heat flux increase in the North Hemisphere
destabilize the system more effectively than low ones, and increases in the
heat fluxes in the Southern Hemisphere tend to stabilize the system.


title:
Thermohaline circulation stability: a box model study - Part II: coupled
  atmosphere-ocean model

abstract:
  A thorough analysis of the stability of a coupled version of an
inter-hemispheric 3-box model of Thermohaline Circulation (THC) is presented.
This study follows a similarly structured analysis on an uncoupled version of
the same model presented in Part I. We study how the strength of THC changes
when the system undergoes forcings representing global warming conditions. Each
perturbation to the initial equilibrium is characterized by the total radiative
forcing realized, by the rate of increase, and by the North-South asymmetry.
The choice of suitably defined metrics allows us to determine the boundary
dividing the set of radiative forcing scenarios that lead the system to
equilibria characterized by a THC pattern similar to the present one, from
those that drive the system to equilibria where the THC is reversed. We also
consider different choices for the atmospheric transport parameterizations and
for the ratio between the high latitude to tropical radiative forcing. We
generally find that fast forcings are more effective than slow forcings in
disrupting the present THC pattern, forcings that are stronger in the northern
box are also more effective in destabilizing the system, and that very slow
forcings do not destabilize the system whatever their asymmetry, unless the
radiative forcings are very asymmetric and the atmospheric transport is a
relatively weak function of the meridional temperature gradient. The changes in
the strength of the THC are primarily forced by changes in the latent heat
transport in the hemisphere, because of its sensitivity to temperature that
arises from the Clausius-Clapeyron relation.


title: Geodesics and distance in classical physics

abstract:
  We formulate geodesics on a manifold in terms of a parallel transfer of a
particle state vector transformed by local Lorentz and Yang-Mills symmetry
groups. This formulation leads to an introduction of a canonical one-form the
eigenvalues of which define distance on a manifold. We suggest an action based
on the canonical distance form and apply it to describe classical particles
with spin. Arguments are presented in favour of scaling distance in the
space-time with a scalar field.


title:
Various Newtonian stresses from macroscopic fluid to microscopic celled
  fluid

abstract:
  We showed that various expressions of stress in different models of fluids
and in different forms of applying Newton's Second Law can be chosen, however
there is always one Newton's Second Law which restricts and provides
flexibility in these expressions. When fluids are regarded as being made of
cells from a microscopic point of view, temperature force (gradient of internal
kinetic energy) can also drive them flow.


title: Phase boundary detection for dilution refrigerators

abstract:
  We describe a device to conveniently measure the positions of the phase
boundaries in a dilution refrigerator. We show how a simple modification of a
standard capacitive level gauge (segmentation of one of the electrodes) permits
a direct calibration of the capacitance versus phase boundary position. We
compare this direct calibration with the indirect procedure that must be
adopted for a conventional capacitive level gauge. The device facilitates the
correct adjustment of the 3He/4He fraction in the dilution refrigerator.


title: The OPERA magnetic spectrometer

abstract:
  The OPERA neutrino oscillation experiment foresees the construction of two
magnetized iron spectrometers located after the lead-nuclear emulsion targets.
The magnet is made up of two vertical walls of rectangular cross section
connected by return yokes. The particle trajectories are measured by high
precision drift tubes located before and after the arms of the magnet.
Moreover, the magnet steel is instrumented with Resistive Plate Chambers that
ease pattern recognition and allow a calorimetric measurement of the hadronic
showers. In this paper we review the construction of the spectrometers. In
particular, we describe the results obtained from the magnet and RPC prototypes
and the installation of the final apparatus at the Gran Sasso laboratories. We
discuss the mechanical and magnetic properties of the steel and the techniques
employed to calibrate the field in the bulk of the magnet. Moreover, results of
the tests and issues concerning the mass production of the Resistive Plate
Chambers are reported. Finally, the expected physics performance of the
detector is described; estimates rely on numerical simulations and the outcome
of the tests described above.


title: Laser wakefield acceleration by petawatt ultra-short laser pulses

abstract:
  An ultra-short (about 30 fs) petawatt laser pulse focused with a wide focal
spot (about 100 microns) in a rarefied plasma (electron density of order
10^{17} per cm^3) excites a nonlinear plasma wakefield which can accelerate
injected electrons up to the GeV energy without any pulse channelling. In these
conditions, propagation of the laser pulse with an over-critical power for
relativistic self-focusing is almost the same as in vacuum. The nonlinear
quasi-plane wake plasma wave, whose amplitude and phase velocity vary along the
laser path, effectively traps and accelerates injected electrons with a wide
range of initial energies. Electrons accelerated along two Rayleigh lengths
(about eight centimeters) can gain an energy up to 1 GeV. In particular, the
electrons trapped from quite a long (of order 330 fs) non-resonant electron
beamlet of 1 MeV particles eventually form a low emittance bunch with energies
in the range 900 MeV and energy spread about 10%. All these conclusions follow
from two-dimensional simulations performed in cylindrical geometry by means of
the fully relativistic time-averaged particle code WAKE.


title: Spatially incoherent modulational instability in a non local medium

abstract:
  We investigate one-dimensional transverse modulational instability in a non
local medium excited with a spatially incoherent source. Employing undoped
nematic liquid crystals in a planar pre-tilted configuration, we investigate
the role of the spectral broadening induced by incoherence in conjunction with
the spatially non local molecular reorientation. The phenomenon is modeled
using the Wigner transform.


title:
Complex-Dynamic Origin of Consciousness and the Critical Choice of
  Sustainability Transition

abstract:
  A quite general interaction process of a multi-component system is analysed
by the extended effective potential method liberated from usual limitations of
perturbation theory or integrable model. The obtained causally complete
solution of the many-body problem reveals the phenomenon of dynamic
multivaluedness, or redundance, of emerging, incompatible system realisations
and dynamic entanglement of system components within each realisation. The
ensuing concept of dynamic complexity (and related intrinsic chaoticity) is
absolutely universal and can be applied to the problem of (natural and
artificial) intelligence and consciousness that dynamically emerge now as a
high enough, properly specified levels of unreduced complexity of a suitable
interaction process. Emergent consciousness can be identified with the
appearance of bound, permanently localised states in the multivalued brain
dynamics from strongly chaotic states of unconscious intelligence, by analogy
with classical behaviour emergence from quantum states at the lowest levels of
complex world dynamics. We show that the main properties of this dynamically
emerging consciousness (and intelligence, at the preceding complexity level)
correspond to empirically derived properties of natural consciousness and
obtain causally substantiated conclusions about their artificial realisation,
including the fundamentally justified paradigm of genuine machine
consciousness. This rigorously defined machine consciousness is different from
both natural consciousness and any mechanistic, dynamically single-valued
imitation of the latter. We use then the same, truly universal concept of
complexity to derive equally rigorous conclusions about mental and social
implications of this complex-dynamic consciousness concept, demonstrating its
critical importance for further progress of science and civilisation.


title: Rational paradigm of plasma physics

abstract:
  In recent studies we have multiply envisioned the irrationality of the
traditional plasma kinetis [1--5]. Its basic false cornerstone was shown to be
the substitution of real plasmas by plasma probabilistic ensembles [1--3]. We
have created culture of plasma studies with refrain from an ensemble
substitution [1-8]. We discovered intense decay of Langmuir quanta, as opposite
to traditional deduction of their conservation [1-3]. The quanta decay prevents
formation of Langmuir condensate in a weak Langmuir turbulence [1, Appendix],
suppresses long-wavelength plasma modulational instability [3], precludes
Langmuir wave collapses [1-3]. Besides, it helped to highlight the uselessness
of hydrodynamic modelling of plasma nonlinear phenomena [2-3], to state an
inadequateness of modelling collisionless plasma by the Vlasov equation [3], to
state of inadequateness of ``Particle in Cell'' method of numerical plasma
simulation to the plasma nature [3]. Finally, it was shown that existed theory
undervalued notably the intensity of induced scattering of short Langmuir waves
[4] and distorted physics of the electron distribution evolution during this
scattering [8]. With this, an extensive revision of the plasma physics and of
the theoretical physics in general are needed.


title: On the Frequency-magnitude Law for Fractal Seismicity

abstract:
  Scaling analysis of seismicity in the space-time-magnitude domain very often
starts from the relation N(m,L)=a(L)*10**(-bm)*L**c for the rate of seismic
events of magnitude M>m in an area of size L. There are some evidences in favor
of multifractal property of seismic process. In this case the choice of the
scale exponent 'c' is not unique. It is shown how different 'c''s are related
to different types of spatial averaging applied to lambda(m, L) and what are
the 'c''s for which the distributions of a(L) best agree for small L.
Theoretical analysis is supplemented with an analysis of California data for
which the above issues were recently discussed on an empirical level.


title: Statistical thermodynamics of strongly coupled plasma

abstract:
  To analyze nonidealities inherent to degenerate plasma, a quantum collective
approach is developed. Thermodynamic functions of a system of partially
degenerate electrons and strongly coupled ions are derived from first
principles. The model takes into account the energy eigenvalues of i) the
thermal translational particle motions, ii) the random collective electron and
ion motions, and iii) the static Coulomb interaction energy of the electrons
and ions in their oscillatory equilibrium positions. These statistical
thermodynamic calculations lead to simple analytical expressions for internal
energy as well as an equation of state (EOS). A dispersion relation for the
high frequency branch of the plasma oscillations is introduced to take into
account the partial degeneracy character and thereby to quantify temperature
finiteness effects on thermodynamic properties of a partially degenerate
plasma. The present results are in good quantitative agreement with the
existing models. These latter being based mainly on numerical experiments while
in the present model more physical insight is explicitly stated. This makes a
contribution to the theoretical knowledge of coupled plasma for thermonuclear
fusion as well as of astrophysical interests.


title:
Multiple micro-optical atom traps with a spherically aberrated laser
  beam

abstract:
  We report on the loading of atoms contained in a magneto-optic trap into
multiple optical traps formed within the focused beam of a CO_{2} laser. We
show that under certain circumstances it is possible to create a linear array
of dipole traps with well separated maxima. This is achieved by focusing the
laser beam through lenses uncorrected for spherical aberration. We demonstrate
that the separation between the micro-traps can be varied, a property which may
be useful in experiments which require the creation of entanglement between
atoms in different micro-traps. We suggest other experiments where an array of
these traps could be useful.


title:
Kinematic dynamo action in a sphere: Effects of periodic time-dependent
  flows on solutions with axial dipole symmetry

abstract:
  Choosing a simple class of flows, with characteristics that may be present in
the Earth's core, we study the ability to generate a magnetic field when the
flow is permitted to oscillate periodically in time. The flow characteristics
are parameterised by D, representing a differential rotation, M, a meridional
circulation, and C, a component characterising convective rolls. Dynamo action
is sensitive to these flow parameters and fails spectacularly for much of the
parameter space where magnetic flux is concentrated into small regions.
  Oscillations of the flow are introduced by varying the flow parameters in
time, defining a closed orbit in the space (D,M). Time-dependence appears to
smooth out flux concentrations, often enhancing dynamo action. Dynamo action
can be impaired, however, when flux concentrations of opposite signs occur
close together as smoothing destroys the flux by cancellation.
  It is possible to produce geomagnetic-type reversals by making the orbit
stray into a region where the steady flows generate oscillatory fields. In this
case, however, dynamo action was not found to be enhanced by the
time-dependence.
  A novel approach is taken to solving the time-dependent eigenvalue problem,
where by combining Floquet theory with a matrix-free Krylov-subspace method we
avoid large memory requirements for storing the matrix required by the standard
approach.


title: Hyperfine Spectroscopy of Optically Trapped Atoms

abstract:
  We perform spectroscopy on the hyperfine splitting of $^{85}$Rb atoms trapped
in far-off-resonance optical traps. The existence of a spatially dependent
shift in the energy levels is shown to induce an inherent dephasing effect,
which causes a broadening of the spectroscopic line and hence an inhomogeneous
loss of atomic coherence at a much faster rate than the homogeneous one caused
by spontaneous photon scattering. We present here a number of approaches for
reducing this inhomogeneous broadening, based on trap geometry, additional
laser fields, and novel microwave pulse sequences. We then show how hyperfine
spectroscopy can be used to study quantum dynamics of optically trapped atoms.

categories: physics.atom-ph cond-mat.soft nlin.CD quant-ph


title:
Calculation of Radiative Corrections to E1 matrix elements in the
  Neutral Alkalis

abstract:
  Radiative corrections to E1 matrix elements for ns-np transitions in the
alkali metal atoms lithium through francium are evaluated. They are found to be
small for the lighter alkalis but significantly larger for the heavier alkalis,
and in the case of cesium much larger than the experimental accuracy. The
relation of the matrix element calculation to a recent decay rate calculation
for hydrogenic ions is discussed, and application of the method to parity
nonconservation in cesium is described.


title: Ultracold Collisions of Fermionic OD Radicals

abstract:
  We discuss consequences of Fermi exchange symmetry on collisions of polar
molecules at low temperatures (below 1 K), considering the OD radical as a
prototype. At low fields and low temperatures, Fermi statistics can stabilize a
gas of OD molecules against state-changing collisions. We find, however, that
this stability does not extend to temperatures high enough to assist with
evaporative cooling. In addition, we establish that a novel ``field-linked''
resonance state of OD dimers exists, in analogy with the similar states
predicted for bosonic OH.


title: Accumulation of three-body resonances above two-body thresholds

abstract:
  We calculate resonances in three-body systems with attractive Coulomb
potentials by solving the homogeneous Faddeev-Merkuriev integral equations for
complex energies. The equations are solved by using the Coulomb-Sturmian
separable expansion approach. This approach provides an exact treatment of the
threshold behavior of the three-body Coulombic systems. We considered the
negative positronium ion and, besides locating all the previously know $S$-wave
resonances, we found a whole bunch of new resonances accumulated just slightly
above the two-body thresholds. The way they accumulate indicates that probably
there are infinitely many resonances just above the two-body thresholds, and
this might be a general property of three-body systems with attractive Coulomb
potentials.


title:
Influence of molecular symmetry on strong-field ionization: Studies on
  ethylene, benzene, fluorobenzene, and chlorofluorobenzene

abstract:
  Using the molecular strong-field approximation we consider the effects of
molecular symmetry on the ionization of molecules by a strong, linearly
polarized laser pulse. Electron angular distributions and total ionization
yields are calculated as a function of the relative orientation between the
molecule and the laser polarization. Our studies focus on ethylene
(C$_2$H$_4$), benzene (C$_6$H$_6$), fluorobenzene (C$_6$H$_5$F), and ortho
chlorofluorobenzene (1,2 C$_6$H$_4$ClF), the molecules representing four
different point groups. The results are compared with experiments, when
available, and with the molecular tunneling theory appropriately extended to
non-linear polyatomic molecules. Our investigations show that the orientational
dependence of ionization yields is primarily determined by the nodal surface
structure of the molecular orbitals.


title: Microwave Spectroscopy of Cold Rubidium Atoms

abstract:
  The effect of microwave radiation on the resonance fluorescence of a cloud of
cold $^{85}Rb$ atoms in a magnetooptical trap is studied. The radiation
frequency was tuned near the hyperfine splitting frequency of rubidium atoms in
the 5S ground state. The microwave field induced magnetic dipole transitions
between the magnetic sublevels of the 5S(F=2) and 5S(F=3) states, resulting in
a change in the fluorescence signal. The resonance fluorescence spectra were
recorded by tuning the microwave radiation frequency. The observed spectra were
found to be substantially dependent on the transition under study and the
frequency of a repump laser used in the cooling scheme.


title: Mott scattering of polarized electrons in a strong laser field

abstract:
  We present analytical and numerical results of the relativistic calculation
of the transition matrix element $S_{fi}$ and differential cross section for
Mott scattering of initially polarized Dirac particles (electrons) in the
presence of strong laser field with linear polarization. We use exact
Dirac-Volkov wave functions to describe the dressed electrons and the collision
process is treated in the first Born approximation. The influence of the laser
field on the degree of polarization of the scattered electron is reported.


title: Spillover on supported catalysts - Dynamic Monte Carlo study

abstract:
  The kinetics of a 2A + B2 = 2AB reaction on supported metal catalyst with
spillover effects is investigated using Dynamic Monte Carlo simulations. In the
presented model A particles can adsorb reversibly on both metal clusters and
the support whereas B2 particles can adsorb dissociatively only on metal
clusters. Particles A can diffuse from the support to metal clusters and vice
versa. The model describes CO oxidation on Pd/Al2O3 catalyst. Steady-state
reaction rates and surface coverages are investigated as functions of partial
pressures of reactants in the gas phase. Simulations show that spillover
effects change the reaction rate dramatically by increasing it and widening the
pressure window of the reaction. In systems with spillover the reaction driven
by an adsorption channel, in addition to a spillover channel, is observed. The
character of the dependence of the reaction rate on reactants' partial
pressures can be controlled by changes of spillover and adsorption channel
contributions.


title: Where will a pen fall to?

abstract:
  We propose a simple experiment that everybody can carry out just while
reading this paper. The only thing we need is a pen or a pencil and a finger.
The dynamics of the falling pen, which is in touch with the finger, depends
essentially on the initial inclination angle of the long axis of the pen. We
point out two different types of trajectories of the falling pen and we
investigate initial conditions for each of them to be realized. We write
differential equations describing the dynamics of the pen and analyze them both
numerically and analytically.

categories: physics.class-ph math-ph math.CA math.MP physics.ed-ph


title: On possible skewon effects on light propagation

abstract:
  We start from a local and linear spacetime relation between the
electromagnetic excitation and the field strength. Then we study the generally
covariant Fresnel surfaces for light rays and light waves. The metric and the
connection of spacetime are left unspecified. Accordingly, our framework is
ideally suited for a search of possible violations of the Lorentz symmetry in
the photon sector of the extended standard model. We discuss how the skewon
part of the constitutive tensor, if suitably parametrized, influences the
Fresnel surfaces and disturbs the light cones of vacuum electrodynamics.
Conditions are specified that yield the reduction of the original quartic
Fresnel surface to the double light cone structure (birefringence) and to the
single light cone. Qualitatively, the effects of the real skewon field can be
compared to those in absorbing material media. In contrast, the imaginary
skewon field can be interpreted in terms of non-absorbing media with natural
optical activity and Faraday effects. The astrophysical data on gamma-ray
bursts are used for deriving an upper limit for the magnitude of the skewon
field.


title: On the first Townsend coefficient at high electric field

abstract:
  Based on the simplified approach it is shown and experimentally confirmed
that gas gain in wire chambers at very low pressure becomes higher on thicker
wires at the same applied high voltage. This is a consequence of the fact that
the first Townsend coefficient at high reduced electric field depends almost
entirely on the mean free path of electrons.


title:
Physics of high-intensity high-energy particle beam propagation in open
  air and outer-space plasmas

abstract:
  This report is a self-contained and comprehensive review of the physics of
propagating pulses of high-intensity high-energy particle beams in pre-existing
or self-generated plasmas. Consideration is given to beams of electrons,
protons, muons, and their antiparticles, as well as to neutral-hydrogen,
positronium, and electron-positron-plasmoid beams. The first part is a
systematic overview of the theory pertaining to propagation, plasma
self-generation, energy/current-losses, and stability of such pulses. The
second part reviews the major full-scale propagation experiments which have
been carried out, in atmospheric and outer-space plasmas, to assess the
validity of theoretical models. It is found that the data available on these
experiments demonstrate that range and stability are in agreement with theory.
In particular, stable self-pinched propagation of high-current charged-particle
beams in the atmosphere is possible over distances equal to several Nordsieck
lengths. In order not to be deflected by Earth's magnetic field, electron-beam
pulses need to be guided by a pre-formed channel, while proton-beam pulses may
under suitable conditions propagate undeflected through both the low- and
high-atmosphere. In ionospheric or outer-space plasmas, very-long-range
propagation across Earth's magnetic field requires GeV to TeV electrons or
positron beams in order for the transverse deflection to be acceptable, while
undeflected propagation is possible for plasmoid beams consisting of co-moving
high-energy particle pairs such as electrons and positrons.


title:
Local spinor structures in V. Fock's and H. Weyl's work on the Dirac
  equation (1929)

abstract:
  In early 1929, V. Fock (initially in collaboration with D. Iwanenko) and H.
Weyl developed independently from each other a general relativistic
generalization of the Dirac equation. In the core, they arrived at the same
theory by the introduction of a local (topologically trivial) spinor structures
and a lifting of the Levi-Civita connection of underlying space-time. They both
observed, in slightly different settings, a characteristic underdetermination
of the spin connection by a complex phase factor, which gave the symbolical
possibility for a reformulation of Weyl's old (1918) idea to characterize the
electromagnetic potential by a differential form transforming as a gauge field.
Weyl and Fock realized the common mathematical core of their respective
approaches in summer 1929, but insisted on differences in perspective. An
interesting difference was discussed by Weyl in his Rouse Ball lecture in
1930,. He contrasted the new type of unification strongly to the earlier
geometrically unified field theories (including his own). He was quite explicit
that he now considered his earlier ideas on geometrization of ``all of
physics'' as premature and declared that the new, more empirically based
approach would have to go a long way before it could be considered as a true
"geometrization" of matter structures.


title:
Global and local perspectives of gravitationally assisted
  negative-phase-velocity propagation of electromagnetic waves in vacuum

abstract:
  Consistently with the Einstein equivalence principle and using an
electromagnetic formulation first suggested by Tamm, we show that a local
observer cannot observe negative-phase-velocity (NPV) propagation of
electromagnetic waves in vacuum, whereas a global observer can appreciate that
phenomenon. Using the specific example of the Kerr metric, we also demonstrate
the possibility of NPV propagation within the ergosphere of a rotating black
hole.


title: Frozen light in periodic stacks of anisotropic layers

abstract:
  We consider a plane electromagnetic wave incident on a periodic stack of
dielectric layers. One of the alternating layers has an anisotropic refractive
index with an oblique orientation of the principal axis relative to the normal
to the layers. It was shown recently (A. Figotin and I. Vitebskiy, Phys. Rev.
E68, 036609 2003) that an obliquely incident light, upon entering such a
periodic stack, can be converted into an abnormal axially frozen mode with
drastically enhanced amplitude and zero normal component of the group velocity.
The stack reflectivity at this point can be very low, implying nearly total
conversion of the incident light into the frozen mode with huge energy density,
compared to that of the incident light. Supposedly, the frozen mode regime
requires strong birefringence in the anisotropic layers - by an order of
magnitude stronger than that available in common anisotropic dielectric
materials. In this paper we show how to overcome the above problem by
exploiting higher frequency bands of the photonic spectrum. We prove that a
robust frozen mode regime at optical wavelengths can be realized in stacks
composed of common anisotropic materials, such as YVO₄, LiNb,
CaCO₃, and the like.


title: Superconducting and Resistive Tilted Coil Magnets

abstract:
  The mathematical foundation is laid for a relatively new type of magnets
generating uniform transverse field - tilted coil magnets. These consist of
concentric nested solenoidal coils with elliptical turns tilted at a certain
angle to the central axis and current flowing in opposite directions in the
coils tilted at opposite angles, generating a perfectly uniform transverse
field. Both superconducting wire-wound and resistive Bitter tilted coils are
discussed. An original analytical method is used to prove that the wire-wound
tilted coils have the ideal distribution of the axial linear current density -
"cosine-theta". Magnetic fields are calculated for a tilted Bitter coil magnet
using an original exact solution for current density in an elliptical Bitter
disk. Superconducting wire-wound tilted coil magnets may become an alternative
for traditional dipole magnets for accelerators, and Bitter tilted coil magnets
are attractive for rotation experiments with a large access port perpendicular
to the field.


title:
Leaking method approach to surface transport in the Mediterranean Sea
  from a numerical ocean model

abstract:
  We use Lagrangian diagnostics (the leaking and the exchange methods) to
characterize surface transport out of and between selected regions in the
Western Mediterranean. Velocity fields are obtained from a numerical model.
Residence times of water of Atlantic origin in the Algerian basin, with a
strong seasonal dependence, are calculated. Exchange rates between these waters
and the ones occupying the northern basin are also evaluated. At surface,
northward transport is dominant, and involves filamental features and eddy
structures that can be identified with the Algerian eddies. The impact on these
results of the presence of small scale turbulent motions is evaluated by adding
Lagrangian diffusion.


title:
Gas gain on single wire chambers filled with pure isobutane at low
  pressure

abstract:
  The gas gain of single-wire chambers filled with isobutane, with cell
cross-section 12x12 mm and wire diameters of 15, 25, 50 and 100 $\mu$m, has
been measured at pressures ranging 12-92 Torr. Contrary to the experience at
atmospheric pressure, at very low pressures the gas gain on thick wires is
higher than that on thin wires at the same applied high voltage as was recently
shown. Bigger wire diameters should be used in wire chambers operating at very
low pressure if multiple scattering on wires is not an issue.


title:
Photoassociation inside an optical dipole trap: absolute rate
  coefficients and Franck-Condon factors

abstract:
  We present quantitative measurements of the photoassociation of cesium
molecules inside a far-detuned optical dipole trap. A model of the trap
depletion dynamics is derived which allows to extract absolute photoassociation
rate coefficients for the initial single-photon photoassociation step from
measured trap-loss spectra. The sensitivity of this approach is demonstrated by
measuring the Franck-Condon modulation of the weak photoassociation transitions
into the low vibrational levels of the outer well of the 0g- state that
correlates to the 6s+6p3/2 asymptote. The measurements are compared to
theoretical predictions. In a magneto-optical trap these transitions have
previously only been observed indirectly through ionization of ground state
molecules.


title: Saturation of Cs2 Photoassociation in an Optical Dipole Trap

abstract:
  We present studies of strong coupling in single-photon photoassociation of
cesium dimers using an optical dipole trap. A thermodynamic model of the trap
depletion dynamics is employed to extract absolute rate coefficents. From the
dependence of the rate coefficient on the photoassociation laser intensity, we
observe saturation of the photoassociation scattering probability at the
unitarity limit in quantitative agreement with the theoretical model by Bohn
and Julienne [Phys. Rev. A, 60, 414 (1999)]. Also the corresponding power
broadening of the resonance width is measured. We could not observe an
intensity dependent light shift in contrast to findings for lithium and
rubidium, which is attributed to the absence of a p or d-wave shape resonance
in cesium.


title:
Comment on 'Towards gravitationally assisted negative refraction of
  light by vacuum'

abstract:
  Reference arXiv:physics/0408021 claims that matter--free regions of spacetime
may support electromagnetic waves for which the phase velocity 3-vector is
oppositely directed to the power flow 3-vector. This was the definition of
negative refraction adopted in \cite{ML}. We here show that this cannot occur
in regions of spacetime for which the electromagnetic energy density is
positive.


title:
Cluster excitation and ionization in high velocity collisions:the atomic
  approach

abstract:
  The independent atom and electron model [1] is introduced in a quantum
context and associated approximations tentatively estimated. Confrontation of
the model to measured ionization and excitation cross sections of small ionic
carbon clusters Cn+ in collisions with helium at an impact velocity of 2.6 a.u
is presented.


title: Resonant Laser Cooling of Circular Accelerator Beams

abstract:
  The resonant laser cooling of circular accelerator beams of relativistic
charged particle is studied. It is shown that in the approximation of the given
external electromagnetic wave amplitude (small gain free electron laser) the
emittance of a beam of charged particles decreases. In the field of particle
energy about 100 in the mass energy units the beam energy losses are
negligible. The discovered effect can be used for cooling of charged particle
beams in various accelerators. The significant cooling rates are possible to
achieve by placing of the cooling device in the appropriate points of the
accelerator orbit. Resonant laser cooling for various cases are considered.
This method of charged particle beams cooling can be applied to circular
accelerators of electron and various relativistic heavy particle beams and has
significantly, about 3-4 orders of magnitude, shorter cooling time in
comparison to any other cooling method.


title:
Structural and energetic properties of nickel clusters: $2 \le N \le
  150$

abstract:
  The four most stable structures of Ni$_N$ clusters with $N$ from 2 to 150
have been determined using a combination of the embedded-atom method in the
version of Daw, Baskes and Foiles, the {\it variable metric/quasi-Newton}
method, and our own {\it Aufbau/Abbau} method. A systematic study of
energetics, structure, growth, and stability of also larger clusters has been
carried through without more or less severe assumptions on the initial
geometries in the structure optimization, on the symmetry, or on bond lengths.
It is shown that cluster growth is predominantly icosahedral with $islands$ of
{\it fcc}, {\it tetrahedral} and {\it decahedral} growth. For the first time in
unbiased computations it is found that Ni$_{147}$ is the multilayer (third
Mackay) icosahedron. Further, we point to an enhanced ability of {\it fcc}
clusters to compete with the icosahedral and decahedral structures in the
vicinity of N=79. In addition, it is shown that conversion from the {\it
hcp}/anti-Mackay kind of icosahedral growth to the {\it fcc}/Mackay one occurs
within a transition layer including several cluster sizes. Moreover, we present
and apply different analytical tools in studying structural and energetic
properties of such a large class of clusters. These include means for
identifying the overall shape, the occurrence of atomic shells, the similarity
of the clusters with, e.g., fragments of the {\it fcc} crystal or of a large
icosahedral cluster, and a way of analysing whether the $N$-atom cluster can be
considered constructed from the $(N-1)$-atom one by adding an extra atom. In
addition, we compare in detail with results from chemical-probe experiment.
Maybe the most central result is that first for clusters with $N$ above 80
general trends can be identified.


title:
Polarizabilities and Effective Parameters for Collections of Spherical
  Nano-Particles Formed by Pairs of Concentric Double-Negative (DNG),
  Single-Negative (SNG) and/or Double-Positive (DPS) Metamaterial Layers

abstract:
  Unusual scattering effects from tiny spherical particles may be obtained when
concentric shells are designed by pairing together 'complementary'
double-negative (DNG), single-negative (SNG), and/or standard double-positive
(DPS) materials. By embedding these highly polarizable scatterers in a host
medium one can achieve a bulk medium with interesting effective parameters.
Some physical insights and justifications for the anomalous polarizability of
these concentric spherical nano-particles and the effective parameters of the
bulk composite medium are discussed.


title:
"Dressing" lines and vertices in calculations of matrix elements with
  the coupled-cluster method and determination of Cs atomic properties

abstract:
  We consider evaluation of matrix elements with the coupled-cluster method.
Such calculations formally involve infinite number of terms and we devise a
method of partial summation (dressing) of the resulting series. Our formalism
is built upon an expansion of the product $C^\dagger C$ of cluster amplitudes
$C$ into a sum of $n$-body insertions. We consider two types of insertions:
particle/hole line insertion and two-particle/two-hole
random-phase-approximation-like insertion. We demonstrate how to ``dress''
these insertions and formulate iterative equations. We illustrate the dressing
equations in the case when the cluster operator is truncated at single and
double excitations. Using univalent systems as an example, we upgrade
coupled-cluster diagrams for matrix elements with the dressed insertions and
highlight a relation to pertinent fourth-order diagrams. We illustrate our
formalism with relativistic calculations of hyperfine constant $A(6s)$ and
$6s_{1/2}-6p_{1/2}$ electric-dipole transition amplitude for Cs atom. Finally,
we augment the truncated coupled-cluster calculations with otherwise omitted
fourth-order diagrams. The resulting analysis for Cs is complete through the
fourth-order of many-body perturbation theory and reveals an important role of
triple and disconnected quadruple excitations.


title:
Transverse Beam Envelope Measurements and the Limitations of the
  3-Screen Emittance Method for Space-Charge Dominated Beams

abstract:
  In its normal mode of operation the Argonne Wakefield Accelerator Facility
uses a high charge (10-100 nC), short pulse (3-5 psec) drive bunch to excite
high-gradient accelerating fields in various slow-wave structures. To generate
this bunch, we designed a 1.5 cell, L-band, rf photocathode gun with an
emittance compensating solenoid to give optimal performance at high-charge; it
has recently completed commissioning. More recently, we have begun to
investigate the possibility of using this gun in a high-brightness, low-charge
operating mode, with charge equal to approximately 1 nC, for high-precision
measurements of wakefields. Two related measurements are reported on in this
paper: (1) measurements of the transverse beam envelope are compared to
predictions from the beam dynamics code PARMELA; and (2) investigations into
the use of a modified 3-screen emittance measurement method that uses a beam
envelope model that includes both space-charge and emittance effects. Both
measurements were made for the 1 nC, 8 MeV beam in the drift region directly
following the rf photocathode gun.


title:
A joint theoretical and experimental study of phenylene-acetylene
  molecular wires

abstract:
  The excited state electronic structure of $\pi$ conjugated
phenylene-acetylene oligomers is calculated using time-dependent density
functional theory (TD-DFT) approaches. The theoretical fluorescence spectra are
analyzed in terms of Frank-Condon active nuclear normal modes and shown to
compare well with experiment. Theoretical and experimental results for the
optical absorption and emission spectra of these molecules indicate that the
conjugation length can be significantly reduced by conformational rotations
about the triple-bonded carbon links. This has serious implications on the
electronic functionalities of polyphenylene-acetylene based molecular wires and
their possible use as charge/energy conduits in nano-assemblies.


title: Extended Born-Oppenheimer equation for tri-state system

abstract:
  We present explicit form of non-adiabatic coupling (NAC) elements of nuclear
Schroedinger equation (SE) for a coupled tri-state electronic manifold in terms
of mixing angles of real electronic basis functions. If the adiabatic-diabatic
transformation (ADT) angles are the mixing angles of electronic basis, ADT
matrix transforms NAC terms to exactly zeros and brings diabatic form of SE.
ADT and NAC matrices satisfy a curl condition and find a novel relation among
the mixing angles for irrotational case. We also find that extended
Born-Oppenheimer (EBO) equations have meaningful solution and can reproduce
numerically exact results only when the equations are gauge invariant.


title:
Influence of electron-ion collisions on Coulomb crystallization of
  ultracold neutral plasmas

abstract:
  While ion heating by elastic electron-ion collisions may be neglected for a
description of the evolution of freely expanding ultracold neutral plasmas, the
situation is different in scenarios where the ions are laser-cooled during the
system evolution. We show that electron-ion collisions in laser-cooled plasmas
influence the ionic temperature, decreasing the degree of correlation
obtainable in such systems. However, taking into account the collisions
increases the ion temperature much less than what would be estimated based on
static plasma clouds neglecting the plasma expansion. The latter leads to both
adiabatic cooling of the ions as well as, more importantly, a rapid decrease of
the collisional heating rate.


title: A Muon Collider Scheme Based on Frictional Cooling

abstract:
  Muon Colliders would usher in a new era of scientific investigation in the
field of high energy particle physics. The cooling of muon beams is proving to
be the greatest obstacle in the realization of a Muon Collider. Monte Carlo
simulations of a muon cooling scheme based on Frictional Cooling were
performed. Critical issues, which require further study, relating to the
technical feasibility of such a scheme are identified. Frictional Cooling, as
outlined in this paper, provides sufficient six-dimensional emittance to make
luminous collisions possible. It holds exciting potential in solving the
problem of Muon Cooling.


title: A 15.2 TFlops Simulation of Geodynamo on the Earth Simulator

abstract:
  For realistic geodynamo simulations, one must solve the magnetohydrodynamic
equations to follow time development of thermal convection motion of
electrically conducting fluid in a rotating spherical shell. We have developed
a new geodynamo simulation code by combining the finite difference method with
the recently proposed spherical overset grid called Yin-Yang grid. We achieved
performance of 15.2 Tflops (46% of theoretical peak performance) on 4096
processors of the Earth Simulator.


title: Ultracold Neutral Plasmas

abstract:
  Ultracold neutral plasmas are formed by photoionizing laser-cooled atoms near
the ionization threshold. Through the application of atomic physics techniques
and diagnostics, these experiments stretch the boundaries of traditional
neutral plasma physics. The electron temperature in these plasmas ranges from
1-1000 K and the ion temperature is around 1 K. The density can approach
$10^{11}$ cm$^{-3}$. Fundamental interest stems from the possibility of
creating strongly-coupled plasmas, but recombination, collective modes, and
thermalization in these systems have also been studied. Optical absorption
images of a strontium plasma, using the Sr$^+$ ${^2S\_{1/2}} -> {^2P\_{1/2}}$
transition at 422 nm, depict the density profile of the plasma, and probe
kinetics on a 50 ns time-scale. The Doppler-broadened ion absorption spectrum
measures the ion velocity distribution, which gives an accurate measure of the
ion dynamics in the first microsecond after photoionization.


title: On the New Symmetries in Electrodynamics and Quantum Theory

abstract:
  The generalized definition of symmetry is formulated. Application of this
definition for symmetric analysis of theoretical physics equations is
considered. The version of electrodynamics is constructed permitting the
faster-than-light motions of particles with real masses. Some elements of
physical interpretation of the proposed theory are presented.


title: Gaussian, Hermite-Gaussian, and Laguerre-Gaussian beams: A primer

abstract:
  The paper aims at presenting a didactic and self-contained overview of
Gauss-Hermite and Gauss-Laguerre laser beam modes. The usual textbook approach
for deriving these modes is to solve the Helmoltz electromagnetic wave equation
within the paraxial approximation. Here, a different technique is presented:
Using the plane wave representation of the fundamental Gaussian mode as seed
function, all higher-order beam modes are derived by acting with differential
operators on this fundamental solution. Even special beam modes as the recently
introduced Bessel beams are easily described within that framework.


title:
Design of a Quantum Source of High-Frequency Gravitational Waves (HFGW)
  and Test Methodology

abstract:
  The generation of High-Frequency Gravitational Waves (HFGW) has been
identified as the required breakthrough that will lead to new forms of space
propulsion. Many techniques have been devised to generate HFGW, but most of
them exhibit marginal efficiency, therefore the power emitted in form of
gravitational waves (GW) is orders of magnitude lower than the input power. The
gravitational wave counterpart of the LASER, termed Gravitational-wave LASER or
"GASER" is the quantum approach to the efficient generation of gravitational
waves. Electrons, protons, muons, etc, all have charge and mass, if accelerated
they usually lose energy through the very fast electric and magnetic channels,
this causes a negligible emission through the gravitational channel. Quantum
systems can be engineered to forbid electric and magnetic transitions,
therefore the gravitational spin-2 transitions can take place. A class of
active materials, suitable for making a GASER based on electronic transitions
in the solid state, is identified along with their relevant physical
properties. Means for creating coherence and population inversion and means to
increase the emission probability are described. The expected performances of
the device are derived from quantum gravitational theories. Additional
properties of the active materials are considered to enforce the theoretical
foundation of the device. A proof-of-concept device, operating at about 1 THz,
is described. Experiments are proposed as a natural starting point of the
research.


title: Influence of magnetic fields on cold collisions of polar molecules

abstract:
  We consider cold collisions of OH molecules in the $^2\Pi_{3/2}$ grounds
state, under the influnce of a magnetic field. We find that modest fields of
several thousand gauss can act to suppress inelastic collisions of weak-field
seeking states by two orders of magnitude. We attribute this suppression to two
factors: (i) An indirect coupling of the entrance and the exit channel, in
contrast to the effect of an applied electric field; and (ii) the realtive
motion of the entrance and exit scattering thresholds. In view of these
results, magnetic trapping of OH may prove feasible.


title: Scaling of the Background Brain Dynamics and Alpha Rhythm

abstract:
  The scaling property of the brain dynamics is studied based on the
zero-crossing of the local electroencephalographic (EEG) recording taken from
healthy young adults in eyes closed and eyes open. Evidence of coupling between
the EEG fractal dynamics and the $\alpha$ rhythm is presented. An organization
principle that governs this coupling relationship is proposed. In the $\alpha$
dominant brain state, a possible interpretation using the self-organized
criticality similar to the punctuated equilibrium is discussed.


title: Triatomic Molecular Systems and Three-body forces: The Ar_3 case

abstract:
  We performed bound state calculations to obtain the first few vibrational
states for the Ar_3 molecular system. The equations used are of Faddeev-type
and are solved directly as three-dimensional equations in configuration space,
i.e. without resorting to an explicit partial wave decomposition. In addition
to realistic pairwise interactions, we employ long range three-body forces. Our
results are in good agreement with those obtained by other methods based on
partial wave expansion and show a significant contribution of the three-body
forces (>10%) to the binding energy and thus their inclusion is, in general,
warranted in studying similar triatomic systems.


title:
Above-well, Stark, and potential-barrier resonances of an open square
  well in a static external electric field

abstract:
  Besides the well known Stark resonances, which are localized in the potential
well and tunnel through the potential barrier created by the dc-field,
"strange" long and short-lived resonances are analytically obtained. These
resonances are not localized inside the potential well. We show that the narrow
ones are localized above the potential well. These narrow resonances give rise
to a {\it peak structure} in a 1D scattering experiment. We also show that the
broad overlapping resonances are associated with the static electric field
potential barrier. These "strange" overlapping resonances do not give rise to a
{\it peak structure} in a 1D scattering experiment. We propose a 2D
experimental set-up where in principle these short-lived states should be
observed as {\it peaks}. Broad overlapping resonances, associated only with the
static electric field potential barrier, could also have observable effects in
a $N>1$ array of quantum wells in the presence of a truncated static electric
field. This last problem is associated with the resonance tunnelling phenomena
which are used in the construction of resonance-tunnelling diodes and
transistors.


title: Low-energy excitations of a linearly Jahn-Teller coupled orbital quintet

abstract:
  The low-energy spectra of the single-mode h x (G+H) linear Jahn-Teller model
is studied by means of exact diagonalization. Both eigenenergies and
photoemission spectral intensities are computed. These spectra are useful to
understand the vibronic dynamics of icosahedral clusters with partly filled
orbital quintet molecular shells, for example C60 positive ions.


title: Intrabeam scattering growth rates for a bi-gaussian beam

abstract:
  This note finds results for the intrabeam scattering growth rates for a
bi-gaussian distribution. The bi-gaussian distribution is interesting for
studying the possibility of using electron cooling in RHIC. Experiments and
computer studies indicate that in the presence of electron cooling, the beam
distribution changes so that it developes a strong core and a long tail which
is not described well by a gaussian, but may be better described by a
bi-gaussian. Being able to compute the effects of intrabeam scattering for a
bi-gaussian distribution would be useful in computing the effects of electron
cooling, which depend critically on the details of the intrabeam scattering.
The calculation is done using the reformulation of intrabeam scattering theory
given in [1] based on the treatments given by A. Piwinski [2] and J. Bjorken
and S.K. Mtingwa [3]. The bi-gaussian distribution is defined below as the sum
of two gaussians in the particle coordinates $x,y,s,p_x,p_y,p_s$. The gaussian
with the smaller dimensions produces most of the core of the beam, and the
gaussian with the larger dimensions largely produces the long tail of the beam.
The final result for the growth rates are expressed as the sum of three terms
which can be interperted respectively as the contribution to the growth rates
due to the scattering of the particles in the first gaussian from themselves,
the scattering of the particles in the second gaussian from themselves, and the
scattering of the particles in the first gaussian from the particles in the
second gaussian.


title:
Applicability of Gaussian Noise Approximation for Optically
  Pre-Amplified DPSK Receivers with Balanced Detection

abstract:
  This letter presents a comparison of exact probability density function with
the Gaussian noise approximation in optically pre-amplified DPSK receivers with
optical Mach-Zehnder interferometer demodulation (MZI) and balanced detection,
including the impact of phase noise. It is found that the Gaussian noise
approximation significantly over-estimates ASE-ASE beat noise in DPSK receivers
with balanced detection particularly when phase noise is negligible, compared
to IM/DD receivers, ASE- amplified spontaneous emission. However, the Gaussian
noise approximation is still applicable for DPSK receivers with balanced
detection and the measured 3-dB advantage is predicted by the Gaussian noise
distribution.


title: Photoassociative spectroscopy at long range in ultracold strontium

abstract:
  We report photoassociative spectroscopy of $^{88}$Sr$_2$ in a magneto-optical
trap operating on the ${^1S_0}\to{^3P_1}$ intercombination line at 689 nm.
Photoassociative transitions are driven with a laser red-detuned by 600-2400
MHz from the ${^1S_0}\to{^1P_1}$ atomic resonance at 461 nm. Photoassociation
takes place at extremely large internuclear separation, and the
photoassociative spectrum is strongly affected by relativistic retardation. A
fit of the transition frequencies determines the ${^1P_1}$ atomic lifetime
($\tau=5.22 \pm 0.03$ ns) and resolves a discrepancy between experiment and
recent theoretical calculations.


title:
Synchronization of the Frenet-Serret linear system with a chaotic
  nonlinear system by feedback of states

abstract:
  A synchronization procedure of the generalized type in the sense of Rulkov et
al [Phys. Rev. E 51, 980 (1995)] is used to impose a nonlinear Malasoma chaotic
motion on the Frenet-Serret system of vectors in the differential geometry of
space curves. This could have applications to the mesoscopic motion of
biological filaments


title: Study on MHD activity in Tokamaks

abstract:
  The tearing mode instability and the associated magnetic islands can lead to
a degradation of tokamak plasma performance and eventually to a disruption. A
crucial issue for the extension of advanced tokamak scenarios to long pulse
operation is to avoid these MHD instabilities. Prevention of disruptions and
limitations of adverse effect on energy confinement depend on the avoidance of
formation of magnetic islands, and it depends also on the successful control of
the growth modes excited by intrinsic plasma effects such as the neo-classical
drive of unfavourable bootstrap current gradient at some q rational surfaces.
In this paper are described in the influence of mode coupling on the nonlinear
evolution of rotating magnetic islands.


title: On dynamical tunneling and classical resonances

abstract:
  This letter establishes a firm relationship between classical nonlinear
resonances and the phenomenon of dynamical tunneling. It is shown that the
classical phase space with its hierarchy of resonance islands completely
characterizes dynamical tunneling. In particular, it is not important to invoke
criteria such as the size of the islands and presence or absence of avoided
crossings for a consistent description of dynamical tunneling in
near-integrable systems.


title: Safe domain and elementary geometry

abstract:
  A classical problem of mechanics involves a projectile fired from a given
point with a given velocity whose direction is varied. This results in a family
of trajectories whose envelope defines the border of a 'safe' domain. In the
simple cases of a constant force, harmonic potential and Kepler or Coulomb
motion, the trajectories are conic curves whose envelope in a plane is another
conic section which can be derived either by simple calculus or by geometrical
considerations. The case of harmonic forces reveals a subtle property of the
maximal sum of distances within an ellipse.


title: The null subspace of G(4,1) as source of the main physical theories

abstract:
  It is the author's belief that a perfect theory will eventually be
formulated, where geometry and physics become indistinguishable, so that the
complete understanding of space properties, together with proper assignments
between geometric and physical entities, will provide all necessary
predictions. The author intends to show that GR and Quantum Mechanics (QM) can
be seen as originating from properties of the null subspace of 5-dimensional
space with signature (-++++), together with its associated geometric algebra
G(4,1). Besides generating GR and QM, the same space generates also
4-dimensional Euclidean space where dynamics can be formulated and is quite
often equivalent to the relativistic counterpart. Euclidean relativistic
dynamics resembles Fermat's principle extended to 4 dimensions and is thus
designated as 4-Dimensional Optics (4DO). In this presentation the author uses
G(4,1) with imposition of the null displacement length condition and derives
the method to transpose between the metrics of GR and 4DO; this transition is
proven viable for stationary metrics. It is hopeless to apply Einstein type
equations in 4DO, for the simple reason that a null Ricci tensor always leads
to a metric diverging to infinity. The author uses geometric arguments to
establish alternative equations which are solved for the case of a stationary
mass and produce a solution equivalent to Schwarzschild's metric in terms of
PPN parameters. As a further development, the author analyses the case of a
monogenic function in G(4,1). The monogenic condition produces an equation that
can be conveniently converted into Dirac's, with the added advantage that it
has built in standard model gauge group symmetry.


title:
Azimuthally polarized spatial dark solitons: exact solutions of
  Maxwell's equations in a Kerr medium

abstract:
  Spatial Kerr solitons, typically associated with the standard paraxial
nonlinear Schroedinger equation, are shown to exist to all nonparaxial orders,
as exact solutions of Maxwell's equations in the presence of vectorial Kerr
effect. More precisely, we prove the existence of azimuthally polarized,
spatial, dark soliton solutions of Maxwell's equations, while exact linearly
polarized (2+1)-D solitons do not exist. Our ab initio approach predicts the
existence of dark solitons up to an upper value of the maximum field amplitude,
corresponding to a minimum soliton width of about one fourth of the wavelength.


title: Parity and the Spin-Statistics Connection

abstract:
  The spin-statistics connection is obtained in a simple and elementary way for
general causal fields by using the parity operation to exchange spatial
coordinates in the scalar product of a locally commuting field operator,
evaluated at position x, with the same field operator evaluated at -x, at equal
times.


title:
Plasma synthesis of single crystal silicon nanoparticles for novel
  electronic device applications

abstract:
  Single-crystal nanoparticles of silicon, several tens of nm in diameter, may
be suitable as building blocks for single-nanoparticle electronic devices.
Previous studies of nanoparticles produced in low-pressure plasmas have
demonstrated the synthesis nanocrystals of 2-10 nm diameter but larger
particles were amorphous or polycrystalline. This work reports the use of a
constricted, filamentary capacitively coupled low-pressure plasma to produce
single-crystal silicon nanoparticles with diameters between 20-80 nm. Particles
are highly oriented with predominant cubic shape. The particle size
distribution is rather monodisperse. Electron microscopy studies confirm that
the nanoparticles are highly oriented diamond-cubic silicon.


title:
Probabilistic forecasts of temperature: measuring the utility of the
  ensemble spread

abstract:
  The spread of ensemble weather forecasts contains information about the
spread of possible future weather scenarios. But how much information does it
contain, and how useful is that information in predicting the probabilities of
future temperatures? One traditional answer to this question is to calculate
the spread-skill correlation. We discuss the spread-skill correlation and how
it interacts with some simple calibration schemes. We then point out why it is
not, in fact, a useful measure for the amount of information in the ensemble
spread, and discuss a number of other measures that are more useful.


title: Spontaneous decay rates in active waveguides

abstract:
  We present a new method to measure the guided, radiated and total decay rates
in one-dimensional waveguides. It is also theoretically shown that large
modifications of the total decay rate can be achieved in realistic EDFAs and
EDWAs with effective mode area radii smaller than ~ 1 micrometer.


title:
Gain and Efficiency Enhancement in Free Electron Laser by Means of
  Modulated Electron Beam

abstract:
  Beam premodulation on free electron laser (FEL) offers considerable
enhancement in gain and efficiency when the phase of the premodulated beam is
-pi/2 and the beam is highly modulated implying the maximum beam oscillatory
velocity due to wiggler. The growth rate of the FEL instability increases with
the modulation index and reaches maximum when the modulation index $\Delta \sim
1.0$.


title: Dusty plasma liquids

abstract:
  The dusty plasma liquid formed by micro-meter sized particles negatively
charged and suspended in a low pressure discharge background is a good
candidate to study the generic spatio-temporal dynamical behaviors at the
kinetic level through direct optical video-microscopy, because of the sub-mm
interparticle spacing and the slow time scale. In this paper, starting from the
basic picture of the avalanche type stick-slip cooperative hopping process
under the interplay of mutual coupling and the stochastic thermal agitation, we
briefly review our recent study on particle micro-motion and the associated
structural rearrangement. The effect of mesoscopic confinement and external
slow shear drive are also discussed.


title:
Analysis of OPM potentials for multiplet states of 3d transition metal
  atoms

abstract:
  We apply the optimized effective potential method (OPM) to the multiplet
energies of the 3d$^n$ transition metal atoms, where the orbital dependence of
the energy functional with respect to orbital wave function is the
single-configuration HF form. We find that the calculated OPM exchange
potential can be represented by the following two forms. Firstly, the
difference between OPM exchange potentials of the multiplet states can be
approximated by the linear combination of the potentials derived from the
Slater integrals $F^2({\rm 3d,3d})$ and $F^4({\rm 3d,3d})$ for the average
energy of the configuration. Secondly, the OPM exchange potential can be
expressed as the linear combination of the OPM exchange potentials of the
single determinants.


title:
Demonstration of an optical polarization magnifier with low
  birefringence

abstract:
  In any polarimetric measurement technique, enhancing the laser polarization
change of a laser beam before it reaches the analyzer can help in improving the
sensitivity. This can be performed using an optical component having a large
linear dichroism, the enhancement factor being equal to the square root of the
ratio of the two transmission factors. A pile of parallel plates at Brewster
incidence looks appropriate for realizing such a polarization magnifier. In
this paper, we address the problem raised by the interference in the plates and
between the plates, which affects the measurement by giving rise to
birefringence. We demonstrate that wedged plates provide a convenient and
efficient way to avoid this interference. We have implemented and characterized
devices with 4 and 6 wedged plates at Brewster incidence which have led to a
decisive improvement of the signal to noise ratio in our ongoing Parity
Violation measurement.


title: Is the Dirac particle composite?

abstract:
  Classical model S_{Dcl} of the Dirac particle S_D is constructed. S_D is the
dynamic system described by the Dirac equation. For investigation of S_D and
construction of S_{Dcl} one uses a new dynamic method: dynamic disquantization.
This relativistic purely dynamic procedure does not use principles of quantum
mechanics. The obtained classical analog S_{Dcl} is described by a system of
ordinary differential equations, containing the quantum constant $\hbar$ as a
parameter. Dynamic equations for S_{Dcl} are determined by the Dirac equation
uniquely. The dynamic system S_{Dcl} has ten degrees of freedom and cannot be a
pointlike particle, because it has an internal structure. There are two ways of
interpretation of the dynamic system S_{Dcl}: (1) dynamical interpretation and
(2) geometrical interpretation. In the dynamical interpretation the classical
Dirac particle S_{Dcl} is a two-particle structure (special case of a
relativistic rotator). It explains freely such properties of S_D as spin and
magnetic moment, which are strange for pointlike structure. In the geometrical
interpretation the world tube of S_{Dcl} is a ''two-dimensional broken band'',
consisting of similar segments. These segments are parallelograms (or
triangles), but not the straight line segments as in the case of a
structureless particle. Geometrical interpretation of the classical Dirac
particle S_{Dcl} generates a new approach to the elementary particle theory.


title: Numerical study of dynamo action at low magnetic Prandtl numbers

abstract:
  We present a three--pronged numerical approach to the dynamo problem at low
magnetic Prandtl numbers $P_M$. The difficulty of resolving a large range of
scales is circumvented by combining Direct Numerical Simulations, a
Lagrangian-averaged model, and Large-Eddy Simulations (LES). The flow is
generated by the Taylor-Green forcing; it combines a well defined structure at
large scales and turbulent fluctuations at small scales. Our main findings are:
(i) dynamos are observed from $P_M=1$ down to $P_M=10^{-2}$; (ii) the critical
magnetic Reynolds number increases sharply with $P_M^{-1}$ as turbulence sets
in and then saturates; (iii) in the linear growth phase, the most unstable
magnetic modes move to small scales as $P_M$ is decreased and a Kazantsev
$k^{3/2}$ spectrum develops; then the dynamo grows at large scales and modifies
the turbulent velocity fluctuations.


title:
Collisionless wave dissipation in a D-shaped tokamak with Soloviev type
  equilibrium

abstract:
  Parallel permittivity elements are derived for radio frequency waves in an
axisymmetric D-shaped tokamak with Soloviev type equilibrium under arbitrary
aspect ratio, arbitrary elongation and moderate triangularity. The
drift-kinetic equation is solved separately for untrapped (passing or
circulating) and three groups of trapped particles as a boundary-value problem,
accounting for the transit-time and bounce resonances, respectively. It is
shown that the new two groups of trapped particles can appear only in tokamaks
with large elongation and large central beta. Our dielectric characteristics
can be applied for both the large and low aspect ratio tokamaks with circular,
elliptic and D-shaped magnetic surfaces to study the wave propagation and wave
dissipation by electron Landau damping during the plasma heating and current
drive generation. The dissipated wave power is expressed by the summation of
terms including the imaginary parts of both the diagonal and non-diagonal
elements of the parallel permittivity.


title:
Identification of Local Alfven Wave Resonances with Reflectometry as a
  Diagnostic Tool in Tokamaks

abstract:
  Local Alfven wave (LAW) resonances are excited in tokamak plasmas by an
externally driven electro-magnetic field, with the frequency below the ion
cyclotron frequency, where using of the Alfven waves is assumed. Recently, wave
driven density fluctuations at the LAW resonance m=+/-1, N=+/-2 with few kW
power deposition and 4 MHz frequency were detected in TCABR (Bt =1.1T, q0 =1.1,
n0=1.4-2.0 10^{19}/ m^3) using a fixed frequency (32.4GHz) O-mode
reflectometer. Here, we show that combination of small power deposition in LAW
resonances, swept by plasma density variation or scanned with generator
frequencies, in combination with detection of the density fluctuations in the
LAW resonances by reflectometry can serve as diagnostic tool for identification
of the effective ion mass number Aef and q-profile in tokamaks. The idea is
based on the simultaneous detection of the position of m=+/-1 local AW
resonances, which are excited by M/N=+/-1/+/-2 antenna modes, and m=0 generated
by poloidal mode coupling effect in tokamaks. According to LAW dispersion, the
m=0 resonance depends only on the effective ion mass number and does not depend
on the q-profile. Then, using these data we can define q-value at the position
of m=+/-1 L AW resonances. Using TAE coils with even toroidal modes (N=2, 4,..)
and AW generator in the frequency band 0.6-1 MHz, an application of this method
to Joint European Torus (Bt=2.3T, q0 =1-1.3, n0=5-7 10^19/m^3) is demonstrated.


title: Kinetic approach to the cluster liquid-gas transition

abstract:
  The liquid-gas transition in free atomic clusters is investigated
theoretically based on simple unimolecular rate theories and assuming
sequential evaporations. A kinetic Monte Carlo scheme is used to compute the
time-dependent properties of clusters undergoing multiple dissociations, and
two possible definitions of the boiling point are proposed, relying on the
cluster or gas temperature. This numerical approach is supported by molecular
dynamics simulations of clusters made of sodium atoms or C60 molecules, as well
as simplified rate equation.


title:
Callen's Adiabatic Piston and the Limits of the Second Law of
  Thermodynamics

abstract:
  The limits of the Second Law of Thermodynamics, which reigns undisputed in
the macroscopic world, are investigated at the mesoscopic level, corresponding
to spatial dimensions of a few microns. An extremely simple isolated system,
modeled after Callen's adiabatic piston, [1] can, under appropriate conditions,
be described as a self-organizing Brownian motor and shown to exhibit a
perpetuum mobile behavior.


title: Lamb Shift in Muonic Hydrogen

abstract:
  The Lamb shift in muonic hydrogen continues to be a subject of experimental
and theoretical investigation. Here my older work on the subject is updated to
provide a complementary calculation of the energies of the 2p-2s transitions in
muonic hydrogen.


title: Ionization fronts in negative corona discharges

abstract:
  In this paper we use a hydrodynamic minimal streamer model to study negative
corona discharge. By reformulating the model in terms of a quantity called
shielding factor, we deduce laws for the evolution in time of both the radius
and the intensity of ionization fronts. We also compute the evolution of the
front thickness under the conditions for which it diffuses due to the geometry
of the problem and show its self-similar character.


title:
Probabilistic temperature forecasting: a comparison of four
  spread-regression models

abstract:
  Spread regression is an extension of linear regression that allows for the
inclusion of a predictor that contains information about the variance. It can
be used to take the information from a weather forecast ensemble and produce a
probabilistic prediction of future temperatures. There are a number of ways
that spread regression can be formulated in detail. We perform an empirical
comparison of four of the most obvious methods applied to the calibration of a
year of ECMWF temperature forecasts for London Heathrow.


title: The Four Space-times Model of Reality

abstract:
  We live in a 3+1 space-time that is intended as a description of the universe
with three space dimensions and one time dimension. Space-time dimensionality
seems so natural that it is rarely criticized. Experiments and the highly
successful relativistic theories teach us that there are four fundamental
dimensions, among them is time that is treated as a special dimension. The
specialty of time can be removed, leading to the concept that time is simply a
function of four new fundamental dimensions, which have now identical
properties, in combination with Lorentz invariance. A model is deduced in which
a 4-space, characterized by four space-like coordinates, may host four
"equivalent but orthogonal" space-times, each with three spatial coordinates
and one temporal coordinate. Coordinates are shared; therefore the 4-space and
the four space-times are all in one. Electromagnetic interaction is confined in
each space-time and the role of the speed of light appears to be that of a
barrier for the electromagnetic interaction. The motion of objects can be
described by four-dimensional optics in the 4-space. Each of the four
space-times may host a universe and, in agreement with recent observations, the
proposed model can be directly applied to problems like the cosmological
matter-antimatter asymmetry and dark-matter issues. Space travel may also
benefit from the concepts presented.


title: Wavefront and ray-density plots using seventh-order matrices

abstract:
  The optimization of an optical system benefits greatly from a study of its
aberrations and an identification of each of its elements' contribution to the
overall aberration figures. The matrix formalism developed by one of the
authors was the object of a previous paper and allows the expression of
image-space coordinates as high-order polynomials of object-space coordinates.
In this paper we approach the question of aberrations, both through the
evaluation of the wavefront evolution along the system and its departure from
the ideal spherical shape and the use of ray density plots. Using seventh-order
matrix modeling, we can calculate the optical path between any two points of a
ray as it travels along the optical system and we define the wavefront as the
locus of the points with any given optical path; the results are presented on
the form of traces of the wavefront on the tangential plane, although the
formalism would also permit sagital plane plots. Ray density plots are obtained
by actual derivation of the seventh-order polynomials.


title:
Quantitative analysis of directional spontaneous emission spectra from
  light sources in photonic crystals

abstract:
  We have performed angle-resolved measurements of spontaneous-emission spectra
from laser dyes and quantum dots in opal and inverse opal photonic crystals.
Pronounced directional dependencies of the emission spectra are observed:
angular ranges of strongly reduced emission adjoin with angular ranges of
enhanced emission. It appears that emission from embedded light sources is
affected both by the periodicity and by the structural imperfections of the
crystals: the photons are Bragg diffracted by lattice planes and scattered by
unavoidable structural disorder. Using a model comprising diffuse light
transport and photonic band structure, we quantitatively explain the
directional emission spectra. This provides detailed understanding of the
transport of spontaneously emitted light in real photonic crystals, which is
essential in the interpretation of quantum-optics in photonic band-gap crystals
and for applications wherein directional emission and total emission power are
controlled.


title:
Self-Energy Correction to the Two-Photon Decay Width in Hydrogenlike
  Atoms

abstract:
  We investigate the gauge invariance of the leading logarithmic radiative
correction to the two-photon decay width in hydrogenlike atoms. It is shown
that an effective treatment of the correction using a Lamb-shift "potential"
leads to equivalent results in both the length as well as the velocity gauges
provided all relevant correction terms are taken into account. Specifically,
the relevant radiative corrections are related to the energies that enter into
the propagator denominators, to the Hamiltonian, to the wave functions, and to
the energy conservation condition that holds between the two photons; the form
of all of these effects is different in the two gauges, but the final result is
shown to be gauge invariant, as it should be. Although the actual calculation
only involves integrations over nonrelativistic hydrogenic Green functions, the
derivation of the leading logarithmic correction can be regarded as slightly
more complex than that of other typical logarithmic terms. The dominant
radiative correction to the 2S two-photon decay width is found to be -2.020536
(alpha/pi) (Zalpha)^2 ln[(Zalpha)^-2] in units of the leading nonrelativistic
expression. This result is in agreement with a length-gauge calculation [S. G.
Karshenboim and V. G. Ivanov, e-print physics/9702027], where the coefficient
was given as -2.025(1).


title: An exact expression for the image error in a catadioptric sensor

abstract:
  A catadioptric sensor induces a projection between a given object surface and
an image plane. The prescribed projection problem is the problem of finding a
catadioptric sensor that realizes a given projection. Here we present a
functional that describes the image error induced by a given mirror when
compared with a given projection. This expression can be minimized to find
solutions to the prescribed projection problem. We present an example of this
approach, by finding the optimum spherical mirror that serves as a passenger
side mirror on a motor vehicle.