title: On the GNSS-R Interferometric Complex Field Coherence Time

abstract:
  In this paper we focus on the microwave bistatic scattering process, with the
aim of deriving an expression for the interferometric complex field
auto-correlation function from a static platform. We start from the Fresnel
integral and derive the auto-correlation function in the Fraunhofer and
Modified Fraunhofer regime. The autocorrelation function at short times can be
expressed as a Gaussian with a direction dependent time scale. The directional
modulation is a function of the angle between the scattering direction and the
wave direction. The obtained relation can be used for directional sea state
estimation using one or more GNSS-R coastal receivers.


title: Electrodynamics of a Magnet Moving through a Conducting Pipe

abstract:
  The popular demonstration involving a permanent magnet falling through a
conducting pipe is treated as an axially symmetric boundary value problem.
Specifically, Maxwell's equations are solved for an axially symmetric magnet
moving coaxially inside an infinitely long, conducting cylindrical shell of
arbitrary thickness at nonrelativistic speeds. Analytic solutions for the
fields are developed and used to derive the resulting drag force acting on the
magnet in integral form. This treatment represents a significant improvement
over existing models which idealize the problem as a point dipole moving slowly
inside a pipe of negligible thickness. It also provides a rigorous study of
eddy currents under a broad range of conditions, and can be used for precision
magnetic braking applications. The case of a uniformly magnetized cylindrical
magnet is considered in detail, and a comprehensive analytical and numerical
study of the properties of the drag force is presented for this geometry.
Various limiting cases of interest involving the shape and speed of the magnet
and the full range of conductivity and magnetic behavior of the pipe material
are investigated and corresponding asymptotic formulas are developed.


title: Production of Enhanced Beam Halos via Collective Modes and Colored Noise

abstract:
  We investigate how collective modes and colored noise conspire to produce a
beam halo with much larger amplitude than could be generated by either
phenomenon separately. The collective modes are lowest-order radial eigenmodes
calculated self-consistently for a configuration corresponding to a
direct-current, cylindrically symmetric, warm-fluid Kapchinskij-Vladimirskij
equilibrium. The colored noise arises from unavoidable machine errors and
influences the internal space-charge force. Its presence quickly launches
statistically rare particles to ever-growing amplitudes by continually kicking
them back into phase with the collective-mode oscillations. The halo amplitude
is essentially the same for purely radial orbits as for orbits that are
initially purely azimuthal; orbital angular momentum has no statistically
significant impact. Factors that do have an impact include the amplitudes of
the collective modes and the strength and autocorrelation time of the colored
noise. The underlying dynamics ensues because the noise breaks the
Kolmogorov-Arnol'd-Moser tori that otherwise would confine the beam. These tori
are fragile; even very weak noise will eventually break them, though the time
scale for their disintegration depends on the noise strength. Both collective
modes and noise are therefore centrally important to the dynamics of halo
formation in real beams.


title: Spreadsheet Filtering by FFT Gaussian-based Convolution

abstract:
  Filtering of digital signals is accomplished on an Excel spreadsheet using
fast Fourier transform (FFT) convolution in which the kernel is either a
Gaussian or a cosine modulated Gaussian. Pedagogical examples of low-pass and
band-pass filtering are provided, and the practical value of the spreadsheet is
illustrated with some cases involving an earthquake record generated by a
folded pendulum seismometer.


title:
Non-Destructive Identification of Cold and Extremely Localized Single
  Molecular Ions

abstract:
  A simple and non-destructive method for identification of a single molecular
ion sympathetically cooled by a single laser cooled atomic ion in a linear Paul
trap is demonstrated. The technique is based on a precise determination of the
molecular ion mass through a measurement of the eigenfrequency of a common
motional mode of the two ions. The demonstrated mass resolution is sufficiently
high that a particular molecular ion species can be distinguished from other
equally charged atomic or molecular ions having the same total number of
nucleons.


title: Renormalisation and hierarchies

abstract:
  We describe a new method of calculating the renormalised energy of a field
obeying the Maxwell and Dirac equations. The method does not involve evaluating
integrals but relies instead on summing a geometric series. We show that the
new solution is equivalent to summing over the levels in the gravitational
hierarchies explored previously by Bell and Diaz. We augment our gravitational
model by the introduction of a shell composed of a smooth mixture of negative
and positive energy. This separates the charge from the mass of a body and
leads to a more general hierarchy. Summing over the levels in this then
produces the renormalisation series found above for the electromagnetic field,
as well as the renormalisation series required by gravity.


title: Rotational structures of long-range diatomic molecules

abstract:
  We present a systematic understanding of the rotational structure of a
long-range (vibrationally highly-excited) diatomic molecule. For example, we
show that depending on a quantum defect, the least-bound vibrational state of a
diatomic molecule with $-C_n/r^n$ ($n>2$) asymptotic interaction can have only
1, 2, and up to a maximum of $n-2$ rotational states. A classification scheme
of diatomic molecules is proposed, in which each class has a distinctive
rotational structure and corresponds to different atom-atom scattering
properties above the dissociation limit.


title: Innovation flow through social networks: Productivity distribution

abstract:
  A detailed empirical analysis of the productivity of non financial firms
across several countries and years shows that productivity follows a
non-Gaussian distribution with power law tails. We demonstrate that these
empirical findings can be interpreted as consequence of a mechanism of
exchanges in a social network where firms improve their productivity by direct
innovation or/and by imitation of other firm's technological and organizational
solutions. The type of network-connectivity determines how fast and how
efficiently information can diffuse and how quickly innovation will permeate or
behaviors will be imitated. From a model for innovation flow through a complex
network we obtain that the expectation values of the productivity level are
proportional to the connectivity of the network of links between firms. The
comparison with the empirical distributions reveals that such a network must be
of a scale-free type with a power-law degree distribution in the large
connectivity range.


title:
Discovery of Daemons Makes Power Generation by Daemon-Assisted Catalysis
  of Light Nuclei Fusion in a Ball Lightning a Reality

abstract:
  In 1997, we proposed a model of the ball lightning (BL) whose activity is
accounted for by energy release in the fusion of light nuclei, most probably,
carbon in organic fibers (Proc. ISBL 97, p.157). The fusion is provided by
catalytic action of superheavy negative particles making up the Galactic Dark
Matter. We called them DArk Electric Matter Objects, or daemons. The daemons
are assumed to be elementary black holes (M ~ 10^-5 g) carrying a charge of up
to Ze = 10e. Experiments have culminated in 2000 by the discovery of daemons.
We used the two-screen scintillation technique with a scintillator ZnS(Ag).
Measurements showed the daemon flux striking the Earth to be ~10^-9 cm^-2s^-1
for an object velocity of as low as ~<10-30 km/s. The half-year periodicity of
the flux was revealed, which can be assigned to daemons being captured into
helio- and geocentric orbits as the Solar system moves through the DM
background (see astro-ph/0402367). The next step in creating a daemon-mediated
BL to achieve controlled energy generation through catalytic fusion of carbon
nuclei will be a search for methods of capture and stable holding of a daemon,
which could involve the use of the tip of a carbon fiber, as it apparently
occurs in nature.


title:
Conformational properties of neutral and charged alanine and glycine
  chains

abstract:
  We have investigated the potential energy surface for neutral and charged
alanine and glycine chains consisting of up to 6 amino acids. For these
molecules we have calculated potential energy surfaces as a function of the
Ramachandran angles phi and psi. Our calculations are performed within it ab
initio theoretical framework based on the density functional theory and also
within semi-empirical model approaches. We have demonstrated that the excessive
positive charge of the system influences strongly its geometrical and
conformational properties. With increasing of the excessive charge amino acid
chains become unstable and decay into two or more fragments. We have analysed
how the secondary structure of polypeptide chains influences the formation of
the potential energy landscapes. We have calculated the energy barriers for
transitions between different molecular conformations and determined the ones
being energetically the most favourable.


title: Fission of charged alanine dipeptides

abstract:
  In this work we have performed for the first time a systematic analysis of
the dissociation and fission pathways of neutral, singly and doubly charged
alanine dipeptide ions with the aim to identify the fission mechanism and the
most probable fragmentation channels of these type of molecules. We demonstrate
the importance of rearrangement of the molecule structure during the fission
process. This rearrangement may include transition to another isomer or a
quasi-molecular state before actual separation of the daughter fragments
begins.


title:
A Scintillator Tile-Fiber Preshower Detector for the CDF Central
  Calorimeter

abstract:
  The front face of the CDF central calorimeter is being equipped with a new
Preshower detector, based on scintillator tiles read out by WLS fibers, in
order to cope with the luminosity increase provided by the Main Injector during
the Tevatron's Run II data taking. A light yield of about 40 pe/MIP at the tile
exit was obtained, exceeding the design requirements.


title: Gravity waves over topographical bottoms: Comparison with the experiment

abstract:
  In this paper, the propagation of water surface waves over one-dimensional
periodic and random bottoms is investigated by the transfer matrix method. For
the periodic bottoms, the band structure is calculated, and the results are
compared to the transmission results. When the bottoms are randomized, the
Anderson localization phenomenon is observed. The theory has been applied to an
existing experiment (Belzons, et al., J. Fluid Mech. {\bf 186}, 530 (1988)). In
general, the results are compared favorably with the experimental observation.


title: CVD Diamonds in the BaBar Radiation Monitoring System

abstract:
  To prevent excessive radiation damage to its Silicon Vertex Tracker, the
BaBar experiment at SLAC uses a radiation monitoring and protection system that
triggers a beam abort whenever radiation levels are anomalously high. The
existing system, which employs large area Si PIN diodes as radiation sensors,
has become increasingly difficult to operate due to radiation damage.
  We have studied CVD diamond sensors as a potential alternative for these
silicon sensors. Two diamond sensors have been routinely used since their
installation in the Vertex Tracker in August 2002. The experience with these
sensors and a variety of tests in the laboratory have shown CVD diamonds to be
a viable solution for dosimetry in high radiation environments. However, our
studies have also revealed surprising side-effects.


title: An automated and versatile ultra-low temperature SQUID magnetometer

abstract:
  We present the design and construction of a SQUID-based magnetometer for
operation down to temperatures T = 10 mK, while retaining the compatibility
with the sample holders typically used in commercial SQUID magnetometers. The
system is based on a dc-SQUID coupled to a second-order gradiometer. The sample
is placed inside the plastic mixing chamber of a dilution refrigerator and is
thermalized directly by the 3He flow. The movement though the pickup coils is
obtained by lifting the whole dilution refrigerator insert. A home-developed
software provides full automation and an easy user interface.


title:
Rank distributions of words in additive many-step Markov chains and the
  Zipf law

abstract:
  The binary many-step Markov chain with the step-like memory function is
considered as a model for the analysis of rank distributions of words in
stochastic symbolic dynamical systems. We prove that the envelope curve for
this distribution obeys the power law with the exponent of the order of unity
in the case of rather strong persistent correlations. The Zipf law is shown to
be valid for the rank distribution of words with lengths about and shorter than
the correlation length in the Markov sequence. A self-similarity in the rank
distribution with respect to the decimation procedure is observed.


title:
Rotational cooling of heteronuclear molecular ions with ^1-Sigma,
  ^2-Sigma, ^3-Sigma and ^2-Pi electronic ground states

abstract:
  The translational motion of molecular ions can be effectively cooled
sympathetically to translational temperatures below 100 mK in ion traps through
Coulomb interactions with laser-cooled atomic ions. The ro-vibrational degrees
of freedom, however, are expected to be largely unaffected during translational
cooling. We have previously proposed schemes for cooling of the internal
degrees of freedom of such translationally cold but internally hot
heteronuclear diatomic ions in the simplest case of ^1-Sigma electronic ground
state molecules. Here we present a significant simplification of these schemes
and make a generalization to the most frequently encountered electronic ground
states of heteronuclear molecular ions: ^1-Sigma, ^2-Sigma, ^3-Sigma and ^2-Pi.
The schemes are relying on one or two laser driven transitions with the
possible inclusion of a tailored incoherent far infrared radiation field.


title:
Rayleigh scattering, mode coupling, and optical loss in silicon
  microdisks

abstract:
  High refractive index contrast optical microdisk resonators fabricated from
silicon-on-insulator wafers are studied using an external silica fiber taper
waveguide as a wafer-scale optical probe. Measurements performed in the 1500 nm
wavelength band show that these silicon microdisks can support
whispering-gallery modes with quality factors as high as 5.2 x 10^5, limited by
Rayleigh scattering from fabrication induced surface roughness. Microdisks with
radii as small as 2.5 microns are studied, with measured quality factors as
high as 4.7 x 10^5 for an optical mode volume of 5.3 cubic wavelengths in the
material.


title:
Methods for 3-D vector microcavity problems involving a planar
  dielectric mirror

abstract:
  We develop and demonstrate two numerical methods for solving the class of
open cavity problems which involve a curved, cylindrically symmetric conducting
mirror facing a planar dielectric stack. Such dome-shaped cavities are useful
due to their tight focusing of light onto the flat surface. The first method
uses the Bessel wave basis. From this method evolves a two-basis method, which
ultimately uses a multipole basis. Each method is developed for both the scalar
field and the electromagnetic vector field and explicit ``end user'' formulas
are given. All of these methods characterize the arbitrary dielectric stack
mirror entirely by its 2\times2 transfer matrices for s- and p-polarization. We
explain both theoretical and practical limitations to our method. Non-trivial
demonstrations are given, including one of a stack-induced effect (the mixing
of near-degenerate Laguerre-Gaussian modes) that may persist arbitrarily far
into the paraxial limit. Cavities as large as 50 \lambda are treated, far
exceeding any vectorial solutions previously reported.


title:
Integral equation for the interfacial tension of liquid metal in contact
  with ionic melt

abstract:
  The closed integral equations for the interfacial tension as a function of
external polarization at the liquid metal - ionic melt interface are derived.
The version of Popel'-Pavlov isotherm is applied to the analysis of
electrocapillary curves (ecc), i.e. the dependences of interfacial tension on
electrode potential. The interaction between adsorbed particles is taken into
account within 'two exchange parameters' approximation. The type of the
distribution of electric potential in the double electric layer (del) is
assumed to be like 'in series connected capacitors'. The methods of solution
are proposed for the analysis of the experimental ecc's.


title: The constancy, or otherwise, of the speed of light

abstract:
  New varying speed of light (VSL) theories as alternatives to the inflationary
model of the universe are discussed and evidence for a varying speed of light
reviewed. Work linked with VSL but primarily concerned with deriving Planck's
black body energy distribution for a gas-like aether using Maxwell statistics
is considered also. Doubly Special Relativity, a modification of special
relativity to account for observer dependent quantum effects at the Planck
scale, is introduced and it is found that a varying speed of light above a
threshold frequency is a necessity for this theory.


title: A high-sensitivity laser-pumped $M_x$-magnetometer

abstract:
  We discuss the design and performance of a laser-pumped cesium vapor
magnetometer in the $M_x$-configuration. The device will be implemented for the
control and stabilization of fluctuating magnetic fields and gradients in a new
experiment searching for a permanent electric dipole moment of the neutron. We
have determined the intrinsic sensitivity of the device to be 21 fT with a 1 s
integration time, limited by low frequency noise of the laser power. In the
shot noise limit the magnetometer can reach a sensitivity of 7 fT with a 1 s
integration time. We have used the device to study the magnetic field
fluctuations in a three layer mu-metal shield for integration times in the
range of 2-100 seconds. The lowest values of the fluctuations are traced back
to the stability of the power supply used to generate the field.


title:
The photomultiplier tube testing facility for the Borexino experiment at
  LNGS

abstract:
  A facility to test the photomultiplier tubes (PMTs) for the solar neutrino
detector Borexino was built at the Gran Sasso laboratory. Using the facility
2200 PMTs with optimal characteristics were selected from the 2350 delivered
from the manufacturer.
  The details of the hardware used are presented.


title:
Free Energy Approach to the Formation of an Icosahedral Structure during
  the Freezing of Gold Nanoclusters

abstract:
  The freezing of metal nanoclusters such as gold, silver, and copper exhibits
a novel structural evolution. The formation of the icosahedral (Ih) structure
is dominant despite its energetic metastability. This important phenomenon,
hitherto not understood, is studied by calculating free energies of gold
nanoclusters. The structural transition barriers have been determined by using
the umbrella sampling technique combined with molecular dynamics simulations.
Our calculations show that the formation of Ih gold nanoclusters is attributed
to the lower free energy barrier from the liquid to the Ih phases compared to
the barrier from the liquid to the face-centered-cubic crystal phases.


title: Positronium lifetime in polymers

abstract:
  A model describing the relationship between the ortho--positronium lifetime
and the volume of a void, located in a synthetic zeolite, is analyzed. Our
idea, which allows us to take into account the effects of temperature,
comprises the introduction of a non--hermitian term in the Hamiltonian, which
accounts for the annihilation of the ortho--positronium. The predictions of the
present model are also confronted against an already known experimental result.


title:
Experimental demonstration of the slow group velocity of light in
  two-dimensional coupled photonic crystal microcavity arrays

abstract:
  We recently proposed two-dimensional coupled photonic crystal microcavity
arrays as a route to achieve a slow-group velocity of light (flat band) in all
crystal directions. In this paper we present the first experimental
demonstration of such structures with a measured group velocity below 0.008c
and discuss the feasibility of applications such as low-threshold photonic
crystal lasers with increased output powers, optical delay components and
sensors.


title: Two-dimensional coupled photonic crystal resonator arrays

abstract:
  We present the design and fabrication of photonic crystal structures
exhibiting electromagnetic bands that are flattened in all crystal directions,
i.e., whose frequency variation with wavevector is minimized. Such bands can be
used to reduce group velocity of light propagating in arbitrary crystal
direction, which is of importance for construction of miniaturized tunable
optical delay components, low-threshold photonic crystal lasers, and study of
nonlinear optics phenomena.


title:
The Clausius inequality: implications for nonequilibrium thermodynamic
  steady states with NEMD corroboration

abstract:
  The Clausius inequality for closed systems was deduced from the Riemann
integration of closed Carnot cycle loops for irreversible transitions. The
corresponding inequalities for the recently developed open system Carnot cycles
are derived here and their properties indicate that no new nonequilibrium
entropy results from them as has been proposed over the decades. A simulation
using a unique dimer molecule with a hysteresis potential - which fulfills all
the dynamical laws - is used to show breakdown of the local equilibrium
hypothesis. The cardinal Curie principle is shown inadequate as a paradigm to
select force-flux relationships


title:
Boltzmann-Gibbs Entropy Versus Tsallis Entropy: Recent Contributions to
  Resolving the Argument of Einstein Concerning "Neither Herr Boltzmann nor
  Herr Planck has given a definition of W"?

abstract:
  Classical statistical mechanics of macroscopic systems in equilibrium is
based on Boltzmann's principle. Tsallis has proposed a generalization of
Boltzmann-Gibbs statistics. Its relation to dynamics and nonextensivity of
statistical systems are matters of intense investigation and debate. This essay
review has been prepared at the occasion of awarding the 'Mexico Prize for
Science and Technology 2003'to Professor Constantino Tsallis from the Brazilian
Center for Research in Physics.


title:
Relativistic hodograph equation for a two-dimensional stationary
  isentropic hydrodynamical motion

abstract:
  We derive a relativistic hodograph equation for a two-dimensional stationary
isentropic hydrodynamical motion. For the case of stiff matter, when the
velocity of sound coincides with the light speed, the singularity in this
equation disappears and the solutions become regular in all hodograph plane.

categories: physics.flu-dyn astro-ph cond-mat.other gr-qc


title: Negative Ion Drift and Diffusion in a TPC near 1 Bar

abstract:
  Drift velocity and longitudinal diffusion measurements are reported for a
Negative Ion TPC (NITPC) operating with Helium + carbon disulfide gas mixtures
at total pressures from 160 to 700 torr. Longitudinal diffusion at the
thermal-limit was observed for drift fields up to at least 700 V/cm in all gas
mixtures tested. The results are of particular interest in connection with
mechanical simplification of Dark Matter searches such as DRIFT, and for high
energy physics experiments in which a low-Z, low density, gaseous tracking
detector with no appreciable Lorentz drift is needed for operation in very high
magnetic fields.


title: Kinoform refraction lens with diffraction calculation

abstract:
  By direct numerical simulations of the kinoform refractive lens within the
quazioptical approach the effects of shape misalinement were investigated. The
quazioptical approach was based on numerical integration of parabolic equation
for complex wave amplitude by spep-by-step method with "splitting" procedure.
The effect of 2pi- shift compensation was calculated for different orders and
imperfections. The performance of kinoform lens was compared with the compound
refractive lens and thin lens approximation.


title: World Space Observatory/Ultraviolet (WSO/UV): Progress Report

abstract:
  The World Space Observatory/Ultraviolet (WSO/UV) represents a new mission
implementation model for large space missions for astrophysics. The process has
been brought up to enable, fully scientific needs driven, a logic to be applied
to the demands for large collection powers required to undertake space missions
which are complementary to the continuously increasing sensitivity of
ground-based telescopes. One of the assumptions associated with the idea of a
WSO is to avoid the excessive complexity required for multipurpose missions.
Although there may exist purely technological or programmatic policy issues,
which would suggest such more complex missions to be more attractive, many
other aspects, which do not need to be explored in this report, may argue
against such a mission model. Following this precept and other reasons, the
first implementation model for a WSO has been done for the ultraviolet domain
WSO/UV. WSO/UV is a follow-up project of the UN/ESA Workshops on Basic Space
Science, organised annually since 1991.


title: Developing Basic Space Science World Wide: Progress Report

abstract:
  The UN/ESA Workshops on Basic Space Science is a long-term effort for the
development of astronomy and regional and international co-operation in this
field on a world wide basis, particularly in developing nations. The first four
workshops in this series (India 1991, Costa Rica and Colombia 1992, Nigeria
1993, and Egypt 1994) addressed the status of astronomy in Asia and the
Pacific, Latin America and the Caribbean, Africa, and Western Asia,
respectively. One major recommendation that emanated from the first four
workshops was that small astronomical facilities should be established in
developing nations for research and education programmes at the university
level and that such facilities should be networked. Subsequently, material for
teaching and observing programmes for small optical telescopes were developed
or recommended and astronomical telescope facilities have been inaugurated at
UN/ESA Workshops on Basic Space Science in Sri Lanka (1995), Honduras (1997),
and Jordan (1999). UN/ESA Workshops on Basic Space Science in Germany (1996),
France (2000), Mauritius (2001), Argentina (2002), and P.R. China (2004)
emphasised the particular importance of astrophysical data systems and the
virtual observatory concept for the development of astronomy on a world wide
basis. Since 1996, the workshops are contributing to the development of the
World Space Observatory concept. Achievements of the series of workshops are
briefly summarised in this report.


title: A conserved Parity Operator

abstract:
  The symmetry of Nature under a Space Inversion is described by a Parity
operator. Contrary to popular belief, the Parity operator is not unique. The
choice of the Parity operator requires several arbitrary decisions to be made.
It is shown that alternative, equally plausible, choices leads to the
definition of a Parity operator that is conserved by the Weak Interactions. The
operator commonly known as CP is a more appropriate choice for a Parity
operator.


title:
Frictional sliding modes along an interface between identical elastic
  plates subject to shear impact loading

abstract:
  Frictional sliding along an interface between two identical isotropic elastic
plates under impact shear loading is investigated experimentally and
numerically. The plates are held together by a compressive stress and one plate
is subject to edge impact near the interface. The experiments exhibit both a
crack-like and a pulse-like mode of sliding. Plane stress finite element
calculations modeling the experimental configuration are carried out, with the
interface characterized by a rate and state dependent frictional law. For low
values of the initial compressive stress and impact velocity, sliding occurs in
a crack-like mode. For higher values of the initial compressive stress and/or
impact velocity, sliding takes place in a pulse-like mode. A variety of sliding
modes are obtained in the calculations depending on the impact velocity, the
initial compressive stress and the values of interface variables. One
pulse-like mode involves well-separated pulses with the pulse amplitude
increasing with propagation distance. Another pulse-like mode involves a pulse
train of essentially constant amplitude. The propagation speed of the leading
pulse (or of the tip of the crack-like sliding region) is near the longitudinal
wave speed and never less than $\sqrt{2}$ times the shear wave speed.
Supersonic trailing pulses are seen both experimentally and computationally.
The trends in the calculations are compared with those seen in the experiments.
These observations can lead to new insights into the mechanisms of earthquakes.


title: Asymmetric Statistical Errors

abstract:
  Asymmetric statistical errors arise for experimental results obtained by
Maximum Likelihood estimation, in cases where the number of results is finite
and the log likelihood function is not a symmetric parabola. This note
discusses how separate asymmetric errors on a single result should be combined,
and how several results with asymmetric errors should be combined to give an
overall measurement. In the process it considers several methods for
parametrising curves that are approximately parabolic.


title: Novel Gravity Probe B Frame-Dragging Effect

abstract:
  The Gravity Probe B (GP-B) satellite experiment will measure the precession
of on-board gyroscopes to extraordinary accuracy. Such precessions are
predicted by General Relativity (GR), and one component of this precession is
the `frame-dragging' or Lense-Thirring effect, which is caused by the rotation
of the earth. A new theory of gravity, which passes the same extant tests of
GR, predicts, however, a second and much larger `frame-dragging' precession.
The magnitude and signature of this larger effect is given for comparison with
the GP-B data.


title:
The Open Path Phase for Degenerate and Non-degenerate Systems and its
  Relation to the Wave-function Modulus

abstract:
  We calculate the open path phase in a two state model with a slowly (nearly
adiabatically) varying time-periodic Hamiltonian and trace its continuous
development during a period. We show that the topological (Berry) phase attains
$\pi$ or $2 \pi$ depending on whether there is or is not a degeneracy in the
part of the parameter space enclosed by the trajectory. Oscillations are found
in the phase. As adiabaticity is approached, these become both more frequent
and less pronounced and the phase jump becomes increasingly more steep.
Integral relations between the phase and the amplitude modulus (having the form
of Kramers-Kronig relations, but in the time domain) are used as an alternative
way to calculate open path phases. These relations attest to the observable
nature of the open path phase.


title: A Variational Procedure for Time-Dependent Processes

abstract:
  A simple variational Lagrangian is proposed for the time development of an
arbitrary density matrix, employing the "factorization" of the density. Only
the "kinetic energy" appears in the Lagrangian. The formalism applies to pure
and mixed state cases, the Navier-Stokes equations of hydrodynamics, transport
theory, etc. It recaptures the Least Dissipation Function condition of
Rayleigh-Onsager {\bf and in practical applications is flexible}. The
variational proposal is tested on a two level system interacting that is
subject, in one instance, to an interaction with a single oscillator and, in
another, that evolves in a dissipative mode.


title:
Parallel Temperatures in Supersonic Beams: Ultra Cooling of Light Atoms
  seeded in a Heavier Carrier Gas

abstract:
  We have found recently that, in a supersonic expansion of a mixture of two
monoatomic gases, the parallel temperatures of the two gases can be very
different. This effect is large if the seeded gas is highly diluted and if its
atomic mass is considerably smaller than the one of the carrier gas. In the
present paper, we present a complete derivation of our theoretical analysis of
this effect. Our calculation is a natural extension of the existing theory of
supersonic cooling to the case of a gas mixture, in the high dilution limit.
Finally, we describe a set of temperature measurements made on a beam of
lithium seeded in argon. Our experimental results are in very good agreement
with the results of our calculation.


title:
Space-frequency model of amplified spontaneous emission and
  super-radiance in free electron laser operating in the linear and non-linear
  regimes

abstract:
  A three-dimensional, space-frequency model for the excitation of
electromagnetic radiation in a free-electron laser is presented. The approach
is applied in a numerical particle code WB3D, simulating the interaction of a
free-electron laser operating in the linear and non-linear regimes. Solution of
the electromagnetic excitation equations in the frequency domain inherently
takes into account dispersive effects arising from the cavity and the gain
medium. Moreover, it facilitates the consideration of statistical features of
the electron beam and the excited radiation, necessary for the study of
spontaneous emission, synchrotron amplified spontaneous emission (SASE),
super-radiance and noise. We employ the code to study the statistical and
spectral characteristics of the radiation generated in a pulsed beam
free-electron laser operating in the millimeter wavelengths. The evolution of
radiation spectrum, excited when a Gaussian shaped bunch with a random
distribution of electrons is passing through the wiggler, was investigated.


title: Hierarchical Construction of Finite Diabatic Sets, By Mathieu Functions

abstract:
  An extension is given for the standard two component model of adiabatic,
  Born-Oppenheimer (BO) electronic states in a polyatonic molecule, by use of
Mathieu functions of arbitrary order. The curl or compatibility conditions for
the construction of a diabatic set of states based on a finite- dimensional
subset of BO states are not satisfied exactly. It is shown, however, that, by
successively adding higher order Mathieu functions to the BO set, the
compatibility conditions are satisfied with increasingly better accuracy. We
then generalize to situations in which the nonadiabatic couplings (the dynamic
corrections to the BO approximation) are small (though not necessarily zero)
between a finite-dimensional BO subset and the rest of the BO states. We prove
that approximate diabatic sets exist, with an error that is of the order of the
square of the neglected nonadiabatic couplings.


title: Photo-Chemical Applications of Phase-Modulus Interdependencies

abstract:
  After an accolade to Joshua Jortner, we trace the influences of his Chemistry
background in his Physics writings. On the way, we note the richness of Physics
in principles (or large-scale laws) and the fact-orientedness of Chemistry.
  Next we turn to a recent laser-induced electron-detachment experiment and
utilize analytic properties of the developing wave-packet in the (complex) time
domain, studied by us previously, to relate the phase of the optimized laser
field to its intensity. It is suggested that these results can be used to
reduce the labor of pulse optimization in phase-intensity controlled reaction
dynamics. Phase-intensity interdependencies are also established in simulated
results (obtained with the END-algorithm) for photo-excited hydrogen-molecules.


title:
Energy Density of a Dissipative Polarizable Solid by a Lagrangean
  Formalism

abstract:
  A Lagrangean for the dynamics of an electromagnetic field in a dispersive and
dissipative material is constructed (adapting some ideas by Bekenstein and
Hannay) and an expression for the energy density that is positive is obtained
from it. The expression contains extra (sink) degrees of freedom that represent
dissipating modes. In simplified cases the sink modes can be eliminated to
yield an energy density expression in terms of the electromagnetic fields, the
polarization and the magnetization only, but which contains parameters
associated with the sink modes. The method of adding extra modes can be used to
set up a Lagrangean formalism for dissipative systems in general, such that
will reinstate time-translation invariance and will yield a unique energy
density.


title: An optical fiber-based probe for photonic crystal microcavities

abstract:
  We review a novel method for characterizing both the spectral and spatial
properties of resonant cavities within two-dimensional photonic crystals (PCs).
An optical fiber taper serves as an external waveguide probe whose micron-scale
field is used to source and couple light from the cavity modes, which appear as
resonant features in the taper's wavelength-dependent transmission spectrum
when it is placed within the cavity's near field. Studying the linewidth and
depth of these resonances as a function of the taper's position with respect to
the resonator produces quantitative measurements of the quality factor Q and
modal volume Veff of the resonant cavity modes. Polarization information about
the cavity modes can be obtained by studying their depths of coupling when the
cavity is probed along different axes by the taper. This fiber-based technique
has been used to measure Q ~ 40,000 and Veff ~ 0.9 cubic wavelengths in a
graded square lattice PC microcavity fabricated in silicon. The speed and
versatility of this fiber-based probe is highlighted, and a discussion of its
applicability to other wavelength-scale resonant elements is given.


title: Visualization of Cytoskeletal Elements by the Atomic Force Microscope

abstract:
  We describe a novel application of atomic force microscopy (AFM) to directly
visualize cytoskeletal fibers in human foreskin epithelial cells. The nonionic
detergent Triton X-100 in a low concentration was used to remove the membrane,
soluble proteins, and organelles from the cell. The remaining cytoskeleton can
then be directly visualized in either liquid or air-dried ambient conditions.
These two types of scanning provide complimentary information. Scanning in
liquid visualizes the surface filaments of the cytoskeleton, whereas scanning
in air shows both the surface filaments and the total "volume" of the
cytoskeletal fibers. The smallest fibers observed were ca. 50 nm in diameter.
The lateral resolution of this technique was ca.20 nm, which can be increased
to a single nanometer level by choosing sharper AFM tips. Because the AFM is a
true three dimensional technique, we are able to quantify the observed
cytoskeleton by its density and volume. The types of fibers can be identified
by their size, similar to electron microscopy.

categories: physics.bio-ph physics.ins-det physics.med-ph q-bio.CB


title:
Spatial and polarization structure in micro-dome resonators: effects of
  a Bragg mirror

abstract:
  Micro-domes based on a combination of metallic and dielectric multilayer
mirrors are studied using a fully vectorial numerical basis-expansion method
that accurately accounts for the effects of an arbitrary Bragg stack and can
efficiently cover a large range of dome shapes and sizes. Results are examined
from three different viewpoints: (i) the ray-optics limit, (ii) the (semi-)
confocal limit for which exact wave solutions are known, and (iii) the paraxial
approximation using vectorial Gaussian beams.


title:
Two-fluid magnetic island dynamics in slab geometry: I - Isolated
  islands

abstract:
  A set of reduced, 2-D, two-fluid, drift-MHD equations is derived. Using these
equations, a complete and fully self-consistent solution is obtained for an
isolated magnetic island propagating through a slab plasma with uniform but
different ion and electron fluid velocities. The ion and electron fluid flow
profiles around the island are uniquely determined, and are everywhere
continuous. Moreover, the island phase-velocity is uniquely specified by the
condition that there be zero net electromagnetic force acting on the island.
Finally, the ion polarization current correction to the Rutherford island width
evolution equation is evaluated, and found to be stabilizing provided that the
anomalous perpendicular ion viscosity significantly exceeds the anomalous
perpendicular electron viscosity.


title:
Two-fluid magnetic island dynamics in slab geometry: II - Islands
  interacting with resistive walls or static external resonant magnetic
  perturbations

abstract:
  The dynamics of a propagating magnetic island interacting with a resistive
wall or a static external magnetic perturbation is investigated using
two-fluid, drift-MHD theory in slab geometry. In both cases, the island
equation of motion is found to take exactly the same form as that predicted by
single-fluid MHD theory. Three separate ion polarization terms are found in the
Rutherford island width evolution equation. The first is the drift-MHD
polarization term for an isolated island, and is completely unaffected by
interaction with a wall or magnetic perturbation. Next, there is the
polarization term due to interaction with a wall or magnetic perturbation which
is predicted by single-fluid MHD theory. Finally, there is a hybrid of the
other two polarization terms. The sign of this term depends on many factors.
However, under normal conditions, it is stabilizing if the unperturbed island
propagates in the ion diamagnetic direction (in the lab. frame), and
destabilizing if it propagates in the electron diamagnetic direction.


title: 2-d Microcavities: Theory and Experiments

abstract:
  An overview is provided over the physics of dielectric microcavities with
non-paraxial mode structure; examples are microdroplets and edge-emitting
semiconductor microlasers. Particular attention is given to cavities in which
two spatial degrees of freedom are coupled via the boundary geometry. This
generally necessitates numerical computations to obtain the electromagnetic
cavity fields, and hence intuitive understanding becomes difficult. However, as
in paraxial optics, the ray picture shows explanatory and predictive strength
that can guide the design of microcavities. To understand the ray-wave
connection in such asymmetric resonant cavities, methods from chaotic dynamics
are required.


title:
Calculation of the Critical Temperature for 2- and 3-Dimensional Ising
  Models and for 2-Dimensional Potts Models Using the Transfer Matrix Method

abstract:
  A new graphical method is developed to calculate the critical temperature of
2- and 3-dimensional Ising models as well as that of the 2-dimensional Potts
models. This method is based on the transfer matrix method and using the
limited lattice for the calculation. The reduced internal energy per site has
been accurately calculated for different 2-D Ising and Potts models using
different size-limited lattices. All calculated energies intersect at a single
point when plotted versus the reduced temperature. The reduced temperature at
the intersection is 0.4407, 0.2746, and 0.6585 for the square, triangular, and
honeycombs Ising lattices and 1.0050, 0.6309, and 1.4848 for the square,
triangular, and honeycombs Potts lattices, respectively. These values are
exactly the same as the critical temperatures reported in the literature,
except for the honeycomb Potts lattice. For the two-dimensional Ising model, we
have shown that the existence of such an intersection point is due to the
duality relation. The method is then extended to the simple cubic Ising model,
in which the intersection point is found to be dependent on the lattice sizes.
We have found a linear relation between the lattice size and the intersection
point. This relation is used to obtain the critical temperature of the
unlimited simple cubic lattice. The obtained result, 0.221(2), is in a good
agreement with the accurate value of 0.22165 reported by others.


title: Massless Electron and Fractional Spin as Electronic Charge

abstract:
  The standard model (SM) of particle physics has been supported by several
experimental findings, the most remarkable of them being the discovery of the
weak gauge bosons, W and Z. It is expected that the Higgs boson could show up
by 2007 at LHC, CERN. In spite of this, the unsatisfactory features of the SM
at conceptual level, and exclusion of gravity from the unification scheme have
led to explore 'the physics beyond the SM'.
  A critique and comprehensive review of the contemporary fundamental physics
was presented in a monograph completed in the centenary year,1997 of the
discovery of the electron. A radically new approach to address foundational
problems was outlined: masslessness of bare electron, interpretation of the
squared electronic charge in terms of the fractional spin, $e^2/c$; new
physicalsignificance of the electromagnetic potentials, 2+1 dimensional
internal structure of electron and neutrino, and composite photon are some of
the ideas proposed. Though the monograph was reviewed by E. J. Post(Physics
Essays, June1999), it has remained largely inaccessible. I believe some of
these unconventional ideas have a potential to throw light on the fundamental
questions in physics, and therefore deserve a wider dissemination.
  The reader may find illuminating to supplement Section 3 on the weak gauge
bosons with a candid, graceful and personal recollection by Pierre
Darriulat(CERN Courier, April 2004, p.13).


title:
The (absence of a) relationship between thermodynamic and logical
  reversibility

abstract:
  Landauer erasure seems to provide a powerful link between thermodynamics and
information processing (logical computation). The only logical operations that
require a generation of heat are logically irreversible ones, with the minimum
heat generation being $kT \ln 2$ per bit of information lost. Nevertheless, it
will be shown logical reversibility neither implies, nor is implied by
thermodynamic reversibility. By examining thermodynamically reversible
operations which are logically irreversible, it is possible to show that
information and entropy, while having the same form, are conceptually
different.


title:
The measurements of 2200 ETL9351 type photomultipliers for the Borexino
  experiment with the photomultiplier testing facility at LNGS

abstract:
  The results of tests of more than 2200 ETL9351 type PMTs for the Borexino
detector with the PMT test facility are presented. The PMTs characteristics
relevant for the proper detector operation and modeling are discussed in
detail.


title: On the Clock Paradox in the case of circular motion of the moving clock

abstract:
  In this paper we deal analytically with a version of the so called clock
paradox in which the moving clock performs a circular motion of constant
radius. The rest clock is denoted as (1), the rotating clock is (2), the
inertial frame in which (1) is at rest and (2) moves is I and, finally, the
accelerated frame in which (2) is at rest and (1) rotates is A. By using the
General Theory of Relativity in order to describe the motion of (1) as seen in
A we will show the following features. I) A differential aging between (1) and
(2) occurs at their reunion and it has an absolute character, i.e. the proper
time interval measured by a given clock is the same both in I and in A. II)
  From a quantitative point of view, the magnitude of the differential aging
between (1) and (2) does depend on the kind of rotational motion performed by
A. Indeed, if it is uniform there is no any tangential force in the direction
of motion of (2) but only normal to it. In this case, the proper time interval
reckoned by (2) does depend only on its constant velocity v=romega. On the
contrary, if the rotational motion is uniformly accelerated, i.e. a constant
force acts tangentially along the direction of motion, the proper time
intervals $do depend$ on the angular acceleration alpha. III) Finally, in
regard to the sign of the aging, the moving clock (2) measures always a
$shorter$ interval of proper time with respect to (1).

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


title: Mass-symmetry breaking in three-body ions

abstract:
  The ground-state energy of three-body ions $(M^+,M^+,m^-)$ evolves when the
like-charge constituents are given different masses. The comparison of
$(m_1^+,m_2^+,m^-)$ with the average of $(m_1^+,m_1^+,m^-)$ and
$(m_2^+,m_2^+,m^-)$ reveals a competition between the symmetric term and the
antisymmetric one. The former dominates in the Born--Oppenheimer regime such as
the (p,t,e) case, while the latter wins for H$^-$-like systems with two
negative light particles surrounding a heavy nucleus. A comparison is also made
with the case of baryons in simple quark models with flavour independence.


title: Exact solution of the Zeeman effect in single-electron systems

abstract:
  Contrary to popular belief, the Zeeman effect can be treated exactly in
single-electron systems, for arbitrary magnetic field strengths, as long as the
term quadratic in the magnetic field can be ignored. These formulas were
actually derived already around 1927 by Darwin, using the classical picture of
angular momentum, and presented in their proper quantum-mechanical form in 1933
by Bethe, although without any proof. The expressions have since been more or
less lost from the literature; instead, the conventional treatment nowadays is
to present only the approximations for weak and strong fields, respectively.
However, in fusion research and other plasma physics applications, the magnetic
fields applied to control the shape and position of the plasma span the entire
region from weak to strong fields, and there is a need for a unified treatment.
In this paper we present the detailed quantum-mechanical derivation of the
exact eigenenergies and eigenstates of hydrogen-like atoms and ions in a static
magnetic field. Notably, these formulas are not much more complicated than the
better-known approximations. Moreover, the derivation allows the value of the
electron spin gyromagnetic ratio $g_s$ to be different from 2. For
completeness, we then review the details of dipole transitions between two
hydrogenic levels, and calculate the corresponding Zeeman spectrum. The various
approximations made in the derivation are also discussed in details.


title:
A simplified model of the source channel of the Leksell Gamma
  Knife$^(R)$: testing multisource configurations with PENELOPE

abstract:
  A simplification of the source channel geometry of the Leksell Gamma
Knife$^{\circledR}$, recently proposed by the authors and checked for a single
source configuration (Al-Dweri et al 2004), has been used to calculate the dose
distributions along the $x$, $y$ and $z$ axes in a water phantom with a
diameter of 160~mm, for different configurations of the Gamma Knife including
201, 150 and 102 unplugged sources. The code PENELOPE (v. 2001) has been used
to perform the Monte Carlo simulations. In addition, the output factors for the
14, 8 and 4~mm helmets have been calculated. The results found for the dose
profiles show a qualitatively good agreement with previous ones obtained with
EGS4 and PENELOPE (v. 2000) codes and with the predictions of
GammaPlan$^{\circledR}$. The output factors obtained with our model agree
within the statistical uncertainties with those calculated with the same Monte
Carlo codes and with those measured with different techniques. Owing to the
accuracy of the results obtained and to the reduction in the computational time
with respect to full geometry simulations (larger than a factor 15), this
simplified model opens the possibility to use Monte Carlo tools for planning
purposes in the Gamma Knife$^{\circledR}$.


title:
Accounting for correlations with core electrons by means of the
  generalized relativistic effective core potentials: Atoms Hg and Pb and their
  compounds

abstract:
  A way to account for correlations between the chemically active (valence) and
innermore (core) electrons in the framework of the generalized relativistic
effective core potential (GRECP) method is suggested. The "correlated" GRECP's
(CGRECP's) are generated for the Hg and Pb atoms. Only correlations for the
external twelve and four electrons of them, correspondingly, should be treated
explicitly in the subsequent calculations with these CGRECP's whereas the
innermore electrons are excluded from the calculations. Results of atomic
calculations with the correlated and earlier GRECP versions are compared with
the corresponding all-electron Dirac-Coulomb values. Calculations with the
above GRECP's and CGRECP's are also carried out for the lowest-lying states of
the HgH molecule and its cation and for the ground state of the PbO molecule as
compared to earlier calculations and experimental data. The accuracy for the
vibrational frequencies is increased up to an order of magnitude and the errors
for the bond lengths (rotational constants) are decreased in about two times
when the correlated GRECP's are applied instead of earlier GRECP versions
employing the same innercore-outercore-valence partitioning.


title:
Do Cosmic Backgrounds Cyclical Renew by Matter and Quanta Emissions? The
  Origin of Backgrounds, Space Distributions and Cyclical Earth Phenomena by
  Two Phase Dynamics

abstract:
  A numerical coincidence Dp of -0.000489 was found between the ratios of
proton emission at 459-keV and cosmic background at 0.25-keV respect to proton
and to electron proper energy respectively. Multiplying 459-keV and 0.25-keV by
Dp, two more numerical coincidences were found with 0.1-keV background and
0.06-eV of neutrino energy, respectively. Global criticality phenomena plus c
and G discontinued decreasing provoke small cyclical reorganization of
particles and quanta originating background emissions every 30-Myr are propose.
At the beginning of each cycle, gradually emissions from electrons lasting 0.1
Myr originate the 0.25-keV background and, a possible 459-keV background from
proton emissions. At following cycle, the 459-keV quanta makes two emissions of
0.1-keV originating a diffuse background, and 0.25-keV quanta makes two of
0.06-eV originating the relic neutrinos. The Dp is a possible physical constant
that characterize the threshold, which trigger cyclical phenomena at space and
Earth every 30-Myr


title:
Orbit and Optics Improvement by Evaluating the Nonlinear BPM Response in
  CESR

abstract:
  We present an improved system for orbit and betatron phase measurement
utilizing nonlinear models of BPM pickup response. We first describe the
calculation of the BPM pickup signals as nonlinear functions of beam position
using Green's reciprocity theorem with a two-dimensional formalism. We then
describe the incorporation of these calculations in our beam position
measurements by inverting the nonlinear functions, giving us beam position as a
function of the pickup signals, and how this is also used to improve our
measurement of the betatron phase advance. Measurements are presented comparing
this system with the linearized pickup response used historically at CESR.


title:
Analytical Solutions for the Nonlinear Longitudinal Drift Compression
  (Expansion) of Intense Charged Particle Beams

abstract:
  To achieve high focal spot intensities in heavy ion fusion, the ion beam must
be compressed longitudinally by factors of ten to one hundred before it is
focused onto the target. The longitudinal compression is achieved by imposing
an initial velocity profile tilt on the drifting beam. In this paper, the
problem of longitudinal drift compression of intense charged particle beams is
solved analytically for the two important cases corresponding to a cold beam,
and a pressure-dominated beam, using a one-dimensional warm-fluid model
describing the longitudinal beam dynamics.


title: Fuzzy Spacetime: Further Considerations

abstract:
  We consider fuzzy spacetime, quanta of area and related concepts in the
context of latest approaches to Quantum Gravity and show its interface with
usual non-Abelian gauge theory. We also discuss in this context a cosmology
which correctly predicted a dark energy driven acceleratling universe with a
small cosmological constant, amongst other things.


title: 3D Reconstruction Using Optical Images

abstract:
  Various imaging methods for small animals are rapidly gaining acceptance in
biology and medical research. Optical imaging is a very fast and convenient
method of biological interrogation, but suffers from significant disadvantages,
such as the absence of 3D image reconstruction algorithms. This have up until
now impeded progress to a quantitative stage. Here we propose a 3D
reconstruction algorithm for imaging light emitted at depths in small living
animals. We believe the methods discussed here are novel and lead to a novel
imaging paradigm, which we call Light Emission Tomography.


title: Complex States of Simple Molecular Systems

abstract:
  A review is given of phase properties in molecular wave functions, composed
of a number of (and, at least, two) electronic states that become degenerate at
some nearby values of the nuclear configuration. Apart from discussing phases
and interference in classical (non-quantal) systems, including light-waves, the
review looks at the constructability of complex wave functions from observable
quantities ("the phase problem"), at the controversy regarding quantum
mechanical phase-operators, at the modes of observability of phase and at the
role of phases in some non-demolition measurements. Advances in experimental
and (especially) theoretical aspects of Aharonov-Bohm and topological (Berry)
phases are described, including those involving two-electron and relativistic
systems. Several works in the phase control and revivals of molecular
wave-packets are cited as developments and applications of complex-function
theory. Further topics that this review touches on are: coherent states,
semiclassical approximations and the Maslov index. The interrelation between
time and the complex state is noted in the contexts of time delays in
scattering, of time-reversal invariance and of the existence of a molecular
time-arrow.


title: A spaceship with a thruster - one body, one force

abstract:
  A spaceship with one thruster producing a constant magnitude force is
analyzed for various initial conditions. This elementary problem, with one
object acted upon by one force, has value as a challenge to one's physical
intuition and in demonstrating the benefits and limitations of dimensional
analysis. In addition, the problem can serve to introduce a student to special
functions, provide a mechanical model for Fresnel integrals and the associated
Cornu spiral, or be used as an example in a numerical methods course. The
problem has some interesting and perhaps unexpected features.


title:
A pulsed, low-temperature beam of supersonically cooled free radical OH
  molecules

abstract:
  An improved system for creating a pulsed, low-temperature molecular beam of
OH radicals has been developed. We use a pulsed discharge to create OH from
H$_2$O seeded in Xe during a supersonic expansion, where the high-voltage pulse
duration is significantly shorter than the width of the gas pulse. The pulsed
discharge allows for control of the mean speed of the molecular packet as well
as maintains a low temperature supersonic expansion. A hot filament is placed
in the source chamber to initiate the discharge for shorter durations and at
lower voltages, resulting in a translationally and rotationally colder packet
of OH molecules.


title:
Electron-molecule scattering calculations in a 3D finite element
  R-matrix approach

abstract:
  We have implemented a three-dimensional finite element approach, based on
tricubic polynomials in spherical coordinates, which solves the Schrodinger
equation for scattering of a low energy electron from a molecule, approximating
the electron exchange as a local potential. The potential is treated as a sum
of three terms: electrostatic, exchange and polarization. The electrostatic
term can be extracted directly from ab initio codes (GAUSSIAN 98 in the work
described here), while the exchange term is approximated using different local
density functionals. A local polarization potential approximately describes the
long range attraction to the molecular target induced by the scattering
electron.


title:
Surface plasmon polariton propagation around bends at a metal-dielectric
  interface

abstract:
  We analyze theoretically the propagation of surface plasmon polaritons about
a metallic corner with a finite bend radius, using a one-dimensional model
analogous to the scattering from a finite-depth potential well. We obtain
expressions for the energy reflection and transmission coefficients in the
short wavelength limit, as well as an upper bound for the transmittance. In
certain cases we find that propagation on non-planar interfaces may result in
lower losses than on flat surfaces, contrary to expectation. In addition, we
also find that the maximum transmittance depends non-monotonously on the bend
radius, allowing increased transmission with decreasing radius.


title:
Erratum: Light-induced desorption of alkali-metal atoms from paraffin
  coating [Phys. Rev. A 66, 042903 (2002)]

abstract:
  Erratum for paper "Light-induced desorption of alkali-metal atoms from
paraffin coating" [Phys. Rev. A 66, 042903 (2002).


title:
Nanoporous compound materials for optical applications - microlasers and
  microresonators

abstract:
  This book chapter is the first part of a review of nanoporous materials for
optical applications. Whereas the second part [J.Sauer, F. Marlow and
F.Schueth, pp. 153-172 of the same volume] discusses material properties, this
part gives a self-contained discussion of fluorescence and lasing in dielectric
microresonators, with special emphasis on the hexagonal morphology found in
molecular-sieve-dye compounds.


title: Direct measurement of diurnal polar motion by ring laser gyroscopes

abstract:
  We report the first direct measurements of the very small effect of forced
diurnal polar motion, successfully observed on three of our large ring lasers,
which now measure the instantaneous direction of Earth's rotation axis to a
precision of 1 part in 10^8 when averaged over a time interval of several
hours. Ring laser gyroscopes provide a new viable technique for directly and
continuously measuring the position of the instantaneous rotation axis of the
Earth and the amplitudes of the Oppolzer modes. In contrast, the space geodetic
techniques (VLBI, SLR, GPS, etc.) contain no information about the position of
the instantaneous axis of rotation of the Earth, but are sensitive to the
complete transformation matrix between the Earth-fixed and inertial reference
frame. Further improvements of gyroscopes will provide a powerful new tool for
studying the Earth's interior.

categories: physics.geo-ph astro-ph gr-qc physics.space-ph


title: Optimization and performance of an optical cardio-magnetometer

abstract:
  Cardiomagnetometry is a growing field of noninvasive medical diagnostics that
has triggered a need for affordable high-sensitivity magnetometers. Optical
pumping magnetometers are promising candidates satisfying that need since it
was demonstrated that they can map the heart magnetic field. For the
optimization of such devices theoretical limits on the performance as well as
an experimental approach is presented. The promising result is a intrinsic
magnetometric sensitivity of 63 fT / Hz^1/2 a measurement bandwidth of 140 Hz
and a spatial resolution of 28 mm.


title: Relativity in Introductory Physics

abstract:
  A century after its formulation by Einstein, it is time to incorporate
special relativity early in the physics curriculum. The approach advocated here
employs a simple algebraic extension of vector formalism that generates
Minkowski spacetime, displays covariant symmetries, and enables calculations of
boosts and spatial rotations without matrices or tensors. The approach is part
of a comprehensive geometric algebra with applications in many areas of
physics, but only an intuitive subset is needed at the introductory level. The
approach and some of its extensions are given here and illustrated with
insights into the geometry of spacetime.


title: Black hole immunity theorem and dark matter

abstract:
  We prove that the primordial black holes in the early universe did not decay
until the gravity decoupled from the other interactions. Rabinowitz' two
objections to the formation of Holeums are shown to be inapplicable. We show
that primordial black holes having masses beween 8x10^18 GeV and 10^19 GeV
formed gravitational bound states called Holeums when the temperature of the
universe was between 10^30 K and 10^29 K. We prove that the black holes in a
fire ball produced in an accelerator such as the LHC, modified into an inertial
confinement type set up, will not emit Hawking radiation as long as the fire
ball is maintained in thermal equilibrium or is allowed to expand
adiabatically.


title: Size Information Obtained by Using Static Light Scattering Technique

abstract:
  Detailed investigation of static light scattering $(SLS) $ has been attempted
in this work using dilute water dispersions of homogenous spherical particles,
poly($N$-isopropylacrylamide) microgels and simulated data. When
Rayleigh-Gan-Debye approximation is valid, for large particles, the simple size
information, the static radius $R_{s}$ and distribution $G(R_{s}) $, can be
accurately obtained from SLS. For small particles, the root mean-square radius
of gyration $< R_{g}^{2}>_{Zimm}^{1/2}$ and the molar mass of particles
measured using the Zimm plot are discussed. The results show that the molar
mass measured using the Zimm plot over the average molar mass of particles is a
function of the size distribution. With the assistance of simulated data, the
effects of the reflected light and noises have been investigated in detail.
Measuring the static radius from the SLS data provides one method to avoid the
stringent requirements for the sample quantity and the instrument capability at
small scattering angles.


title:
Solution to two-dimensional Incompressible Navier-Stokes Equations with
  SIMPLE, SIMPLER and Vorticity-Stream Function Approaches. Driven-Lid Cavity
  Problem: Solution and Visualization

abstract:
  In that report solution to incompressible Navier - Stokes equations in non -
dimensional form will be presented. Standard fundamental methods: SIMPLE,
SIMPLER (SIMPLE Revised) and Vorticity-Stream function approach are compared
and results of them are analyzed for standard CFD test case - Drived Cavity
flow. Different aspect ratios of cavity and different Reynolds numbers are
studied.


title: Pressure Model of Soft Body Simulation

abstract:
  Motivated by existing models used for soft body simulation which are rather
complex to implement, we present a novel technique which is based on simple
laws of physics and gives high quality results in real-time. We base the
implementation on simple thermodynamics laws and use the Clausius-Clapeyron
state equation for pressure calculation. In addition, this provides us with a
pressure force that is accumulated into a force accumulator of a 3D mesh object
by using an existing spring-mass engine. Finally after integration of Newtons
second law we obtain the behavior of a soft body with fixed or non-fixed air
pressure inside of it.


title: Soliton trains in photonic lattices

abstract:
  We address the formation and propagation of multi-spot soliton packets in
saturable Kerr nonlinear media with an imprinted harmonic transverse modulation
of the refractive index. We show that, in sharp contrast to homogeneous media
where stable multi-peaked solitons do not exist, the photonic lattices support
stable higher-order structures in the form of soliton packets, or soliton
trains. Intuitively, such trains can be viewed as made of several lowest order
solitons bound together with appropriate relative phases and their existence as
stable objects puts forward the concept of compact manipulation of several
solitons as a single entity.


title: The glacial cycles and cosmic rays

abstract:
  The cause of the glacial cycles remains a mystery. The origin is widely
accepted to be astronomical since paleoclimatic archives contain strong
spectral components that match the frequencies of Earth's orbital modulation.
Milankovitch insolation theory contains similar frequencies and has become
established as the standard model of the glacial cycles. However, high
precision paleoclimatic data have revealed serious discrepancies with the
Milankovitch model that fundamentally challenge its validity and re-open the
question of what causes the glacial cycles. We propose here that the ice ages
are initially driven not by insolation cycles but by cosmic ray changes,
probably through their effect on clouds. This conclusion is based on a wide
range of evidence, including results presented here on speleothem growth in
caves in Austria and Oman, and on a record of cosmic ray flux over the past 220
kyr obtained from the 10Be composition of deep-ocean sediments.


title:
On the Probability distribution function of particle density at the edge
  of fusion devices

abstract:
  The Probability Distribution Function (PDF) Pn(n) of the particle density at
the edge of several magnetic fusion devices, including tokamaks, stellarators,
and linear devices, is known to be strongly non-gaussian. In this paper we
present experimental results from RFX Reversed Field Pinch [G. Rostagni, Fus.
Eng. Design 25, 301 (1995)], confirming the universal shape of Pn also for
RFP's. An explanation for the form of Pn is attempted, on the basis of simple
conservation equations. The model result is shown to fitted fairly well
empirical data in a few different experimental scenarios.


title:
Synchronization of the Fermilab Booster and Main Injector for Multiple
  Batch Injection

abstract:
  To date, the 120 GeV Fermilab Main Injector accelerator has accelerated a
single batch of protons from the 8 GeV rapid-cycling Booster synchrotron for
production of antiprotons for Run II. In the future, the Main Injector must
accelerate 6 or more Booster batches simultaneously; the first will be
extracted to the antiproton source, while the remaining are extracted for the
NuMI/MINOS (Neutrinos at the Main Injector / Main Injector Neutrino Oscillation
Search) neutrino experiment. Performing this multi-batch operation while
avoiding unacceptable radioactivation of the beamlines requires a previously
unnecessary synchronization between the accelerators. We describe a mechanism
and present results of advancing or retarding the longitudinal progress of the
Booster beam by active feedback radial manipulation of the beam during the
acceleration period.


title: Optical Deformability of Fluid Interfaces

abstract:
  The formation, deformation, and break-up of liquid interfaces are ubiquitous
phenomena in nature. In the present article we discuss the deformation of a
liquid interface produced by optical radiation forces. Usually, the bending of
such an interface by the radiation pressure of a c.w. laser beam is weak.
However, the effect can be enhanced significantly if one works with a
near-critical phase-separated liquid mixture, whereby the surface tension
becomes weak. The bending may in this way become as large as several tenths of
micrometers, even with the use of only moderate laser power. This
near-criticality is a key element in our experimental investigations as
reviewed in the article. The effect is achieved by working with a micellar
phase of microemulsions, at room temperature. We give a brief survey of the
theory of electromagnetic forces on continuous matter, and survey earlier
experiments in this area, such as the Ashkin-Dziedzic optical radiation force
experiment on a water/air surface (1973), the Zhang-Chang experiment on the
laser-induced deformation of a micrometer-sized spherical water droplet (1988),
and the experiment of Sakai et al. measuring surface tensions of interfaces in
a non-contact manner (2001). Thereafter, we survey results we obtained in
recent years by performing experiments on near-critical interfaces, such as
interface bending in the linear regime, stationary large deformations of liquid
interfaces, asymmetric pressure effects on interfaces under intense
illumination, nonlinear deformations, and laser-sustained liquid columns.


title:
Hadronic Calibration of the ATLAS Liquid Argon End-Cap Calorimeter in
  the Pseudorapidity Region 1.6 < |eta| < 1.8 in Beam Tests

abstract:
  A full azimuthal phi-wedge of the ATLAS liquid argon end-cap calorimeter has
been exposed to beams of electrons, muons and pions in the energy range 6 GeV
<= E <= 200 GeV at the CERN SPS. The angular region studied corresponds to the
ATLAS impact position around the pseudorapidity interval 1.6 < |eta| < 1.8. The
beam test set-up is described. A detailed study of the performance is given as
well as the related intercalibration constants obtained. Following the ATLAS
hadronic calibration proposal, a first study of the hadron calibration using a
weighting ansatz is presented. The results are compared to predictions from
Monte Carlo simulations, based on GEANT 3 and GEANT 4 models.


title: Multiphoton ionization of xenon in the VUV regime

abstract:
  In a recent experiment at the VUV free-electron laser facility at DESY in
Hamburg, the generation of multiply charged ions in a gas of atomic xenon was
observed. This paper develops a theoretical description of multiphoton
ionization of xenon and its ions. The numerical results lend support to the
view that the experimental observation may be interpreted in terms of the
nonlinear absorption of several VUV photons. The method rests on the
Hartree-Fock-Slater independent-particle model. The multiphoton physics is
treated within a Floquet scheme. The continuum problem of the photoelectron is
solved using a complex absorbing potential. Rate equations for the ionic
populations are integrated to take into account the temporal structure of the
individual VUV laser pulses. The effect of the spatial profile of the
free-electron laser beam on the distribution of xenon charge states is
included. An Auger-type many-electron mechanism may play a role in the VUV
multiphoton ionization of xenon ions.


title:
Canonical Lie-transform method in Hamiltonian gyrokinetics: a new
  approach

abstract:
  The well-known gyrokinetic problem regards the perturbative expansion related
to the dynamics of a charged particle subject to fast gyration motion due to
the presence of a strong magnetic field. Although a variety of approaches have
been formulated in the past to this well known problem, surprisingly a purely
canonical approach based on Lie transform methods is still missing. This paper
aims to fill in this gap and provide at the same time new insight in
Lie-transform approaches.


title: Rotary solitons in Bessel photonic lattices

abstract:
  We introduce solitons supported by Bessel photonic lattices in cubic
nonlinear media. We show that the cylindrical geometry of the lattice, with
several concentric rings, affords unique soliton properties and dynamics. In
particular, besides the lowest-order solitons trapped in the center of the
lattice, we find soliton families trapped at different lattice rings. Such
solitons can be set into controlled rotation inside each ring, thus featuring
novel types of in-ring and inter-ring soliton interactions.


title: Efficient Stark deceleration of cold polar molecules

abstract:
  Stark deceleration has been utilized for slowing and trapping several species
of neutral, ground-state polar molecules generated in a supersonic beam
expansion. Due to the finite physical dimension of the electrode array and
practical limitations of the applicable electric fields, only molecules within
a specific range of velocities and positions can be efficiently slowed and
trapped. These constraints result in a restricted phase space acceptance of the
decelerator in directions both transverse and parallel to the molecular beam
axis; hence, careful modeling is required for understanding and achieving
efficient Stark decelerator operation. We present work on slowing of the
hydroxyl radical (OH) elucidating the physics controlling the evolution of the
molecular phase space packets both with experimental results and model
calculations. From these results we deduce experimental conditions necessary
for efficient operation of a Stark decelerator.


title:
XMCD under pressure at the Fe K edge on the energy dispersive beamline
  of the ESRF

abstract:
  The present paper demonstrates the feasibility of X-ray Absorption
Spectroscopy (XAS) and X-ray Magnetic Circular Dichroism (XMCD) at high
pressure at the Fe-K edge on the ID24 energy dispersive beamline of the ESRF.
In 3d transition metals, performing experiments at the hard X-ray K-edge rather
than at the magnetically interesting soft X-ray L-edges represents, the only
way to access the high pressure regime obtainable with Diamond Anvil Cells. The
simultaneous availability of a local structure (XAS) and of a magnetic (XMCD)
probe on the sample in identical thermodynamical conditions is essential to
study correlations between local structural and magnetic properties. We briefly
summarize the state of the art theoretical understanding of K-edge XMCD data,
then illustrate the setup of beamline ID24 for high pressure XMCD experiments
and underline the conditions required to perform measurements at the K-edges of
3d transition metals. Finally, we present two examples of recent high pressure
results at the Fe-K edge in pure Fe and Fe3O4 powder.


title: Relativistic kinetic theory of magnetoplasmas

abstract:
  Recently, an increasing interest in astrophysical as well as laboratory
plasmas has been manifested in reference to the existence of relativistic
flows, related in turn to the production of intense electric fields in
magnetized systems. Such phenomena require their description in the framework
of a consistent relativistic kinetic theory, rather than on relativistic MHD
equations, subject to specific closure conditions. The purpose of this work is
to apply the relativistic single-particle guiding-center theory developed by
Beklemishev and Tessarotto, including the nonlinear treatment of
small-wavelength EM perturbations which may naturally arise in such systems. As
a result, a closed set of relativistic gyrokinetic equations, consisting of the
collisionless relativistic kinetic equation, expressed in hybrid gyrokinetic
variables, and the averaged Maxwell's equations, is derived for an arbitrary
four-dimensional coordinate system.


title:
Theoretical Analysis of Frequency-domain "single-shot" (FDSS) ultrafast
  spectroscopy

abstract:
  "Single-shot" ultrafast spectroscopy based on the frequency encoding of
transient absorbance kinetics using chirped probe pulses is analyzed
theoretically. FDSS has an advantage over pump-probe spectroscopy in a
situation where the "noise" is dominated by amplitude variations of the signal.
Unlike "single-shot" techniques based on spatial encoding of the kinetics, no a
priori knowledge of the excitation profile of the pump is needed. FDSS
spectroscopy can be used for many types of samples, liquid or solid, including
those comparable in thickness to the wavelength of the probe light. Another
advantage is that due to the interference of quasimonochromatic components of
the chirped probe pulse, an oscillation pattern near the origin of the FDSS
kinetics emerges. This interference pattern is unique and can be used to
determine the complex dielectric function of the photogenerated species.


title:
Frequency-domain "single-shot" (FDSS) transient absorption spectroscopy
  using a variable-length grating pair compressor

abstract:
  Single-shot ultrafast spectroscopy based on the frequency encoding of
transient absorbance kinetics (FDSS) is demonstrated. These kinetics are
sampled spectrally using linearly chirped pulses derived from a Ti:sapphire
laser. A variable length grating pair compressor is used to provide group
velocity dispersion out to -1.6 ps^2 and achieve the sampling of 512 channels
per a 2-to-160 ps window with sensitivity > 5e-4. The possibilities of FDSS are
illustrated with studies of three photon ionization of liquid water and
one-photon excitation of a thin-film


title:
Importance of small earthquakes for stress transfers and earthquake
  triggering

abstract:
  We estimate the relative importance of small and large earthquakes for static
stress changes and for earthquake triggering, assuming that earthquakes are
triggered by static stress changes and that earthquakes are located on a
fractal network of dimension D. This model predicts that both the number of
events triggered by an earthquake of magnitude m and the stress change induced
by this earthquake at the location of other earthquakes increase with m as
\~10^(Dm/2). The stronger the spatial clustering, the larger the influence of
small earthquakes on stress changes at the location of a future event as well
as earthquake triggering. If earthquake magnitudes follow the Gutenberg-Richter
law with b>D/2, small earthquakes collectively dominate stress transfer and
earthquake triggering, because their greater frequency overcomes their smaller
individual triggering potential. Using a Southern-California catalog, we
observe that the rate of seismicity triggered by an earthquake of magnitude m
increases with m as 10^(alpha m), where alpha=1.00+-0.05. We also find that the
magnitude distribution of triggered earthquakes is independent of the
triggering earthquake magnitude m. When alpha=b, small earthquakes are roughly
as important to earthquake triggering as larger ones. We evaluate the fractal
correlation dimension of hypocenters D=2 using two relocated catalogs for
Southern California, and removing the effect of short-term clustering. Thus
D=2alpha as predicted by assuming that earthquake triggering is due to static
stress. The value D=2 implies that small earthquakes are as important as larger
ones for stress transfers between earthquakes.


title:
Variational principle for the relativistic hydrodynamic flows with
  discontinuities, and local invariants of motion

abstract:
  A rigorous method for introducing the variational principle describing
relativistic ideal hydrodynamic flows with all possible types of
discontinuities (including shocks) is presented in the framework of an exact
Clebsch type representation of the four-velocity field as a bilinear
combination of the scalar fields. The boundary conditions for these fields on
the discontinuities are found. We also discuss the local invariants caused by
the relabeling symmetry of the problem and derive recursion relations linking
invariants of different types. These invariants are of specific interest for
stability problems. In particular, we present a set of invariants based on the
relativistic generalization of the Ertel invariant.


title:
Optical Coupling of Mie Particles Adsorbed on a Whispering Gallery
  Resonator

abstract:
  We present an experimental observation on particles adsorbed to a whispering
gallery mode (WGM) optical resonator produced from a glass sphere of about 100
micro meter in radius. For spherical adsorbates of radius about 100 nm, we find
a striking nonlinear dependence of the induced wavelength shift on the adsorbed
particle density, whereas for Rayleigh particles with dimensions much smaller
than the infrared wavelength the dependence is linear with particle density. An
explanation of the anamalous effect based on optical coupling between
meso-optic adsorbates is suggested.


title: Narrow Line Cooling and Momentum-Space Crystals

abstract:
  Narrow line laser cooling is advancing the frontier for experiments ranging
from studies of fundamental atomic physics to high precision optical frequency
standards. In this paper, we present an extensive description of the systems
and techniques necessary to realize 689 nm 1S0 - 3P1 narrow line cooling of
atomic 88Sr. Narrow line cooling and trapping dynamics are also studied in
detail. By controlling the relative size of the power broadened transition
linewidth and the single-photon recoil frequency shift, we show that it is
possible to continuously bridge the gap between semiclassical and quantum
mechanical cooling. Novel semiclassical cooling process, some of which are
intimately linked to gravity, are also explored. Moreover, for laser
frequencies tuned above the atomic resonance, we demonstrate momentum-space
crystals containing up to 26 well defined lattice points. Gravitationally
assisted cooling is also achieved with blue-detuned light. Theoretically, we
find the blue detuned dynamics are universal to Doppler limited systems. This
paper offers the most comprehensive study of narrow line laser cooling to date.


title: Dimensions and Units in Electrodynamics

abstract:
  We sketch the foundations of classical electrodynamics, in particular the
transition that took place when Einstein, in 1915, succeeded to formulate
general relativity. In 1916 Einstein demonstrated that, with a choice of
suitable variables for the electromagnetic field, it is possible to put
Maxwell's equation into a form that is covariant under general coordinate
transformations. This unfolded, by basic contributions of Kottler, Cartan, van
Dantzig, Schouten & Dorgelo, Toupin & Truesdell, and Post, to what one may call
{\em premetric classical electrodynamics.} This framework will be described
shortly. An analysis is given of the physical dimensions involved in
electrodynamics and subsequently the question of units addressed. It will be
pointed out that these results are untouched by the generalization of classical
to quantum electrodynamics (QED). We compare critically our results with those
of {\sl L.B. Okun} which he had presented at a recent conference.

categories: physics.class-ph gr-qc hep-th physics.gen-ph


title: Anharmonic quantum contribution to vibrational dephasing

abstract:
  Based on a quantum Langevin equation and its corresponding Hamiltonian within
a c-number formalism we calculate the vibrational dephasing rate of a cubic
oscillator. It is shown that leading order quantum correction due to
anharmonicity of the potential makes a significant contribution to the rate and
the frequency shift. We compare our theoretical estimates with those obtained
from experiments for small diatomics $N_2$, $O_2$ and $CO$.


title:
Theory of space-charge waves on gradient-profile relativistic electron
  beam: an analysis in propagating eigenmodes

abstract:
  We developed an exact analytical treatment for space-charge waves within a
relativistic electron beam in terms of (self-reproducing) propagating
eigenmodes. This result is of obvious theoretical relevance as it constitutes
one of the few exact solution for the evolution of charged particles under the
action of self-interactions. It also has clear numerical applications in
particle accelerator physics where it can be used as the first self-consistent
benchmark for space-charge simulation programs. Today our work is of practical
relevance in FEL technology in relation with all those schemes where an
optically modulated electron beam is needed and with the study of longitudinal
space-charge instabilities in magnetic bunch compressors.


title: Thermodynamics of MHD flows with axial symmetry

abstract:
  We present strategies based upon extremization principles, in the case of the
axisymmetric equations of magnetohydrodynamics (MHD). We study the equilibrium
shape by using a minimum energy principle under the constraints of the MHD
axisymmetric equations. We also propose a numerical algorithm based on a
maximum energy dissipation principle to compute in a consistent way the
equilibrium states. Then, we develop the statistical mechanics of such flows
and recover the same equilibrium states giving a justification of the minimum
energy principle. We find that fluctuations obey a Gaussian shape and we make
the link between the conservation of the Casimirs on the coarse-grained scale
and the process of energy dissipation.


title:
The ATLAS liquid argon hadronic end-cap calorimeter: construction and
  selected beam test results

abstract:
  ATLAS has chosen for its Hadronic End-Cap Calorimeter (HEC) the copper-liquid
argon sampling technique with flat plate geometry and GaAs pre-amplifiers in
the argon. The contruction of the calorimeter is now approaching completion.
Results of production quality checks are reported and their anticipated impact
on calorimeter performance discussed. Selected results, such as linearity,
electron and pion energy resolution, uniformity of energy response, obtained in
beam tests both of the Hadronic End-Cap Calorimeter by itself, and in the ATLAS
configuration where the HEC is in combination with the Electromagnetic End-Cap
Calorimeter (EMEC) are described.


title: On linear momentum in quasistatic electromagnetic systems

abstract:
  The analysis of Aguirregabiria, Hernandez, and Rivas [2004 Eur. J. Phys. 25,
555--567] of the electromagnetic linear momentum in quasistatic systems omits
the presence of an equal and opposite hidden mechanical momentum in such
systems. The existence of hidden mechanical momentum ensures that the
action--reaction law holds for the forces between the charge- and
current-carrying bodies of a quasistatic system, and thus the total mechanical
momentum associated with the motion of such bodies in a closed quasistatic
system is conserved.


title:
Coherent stacking of laser pulses in a high-Q optical cavity for
  accelerator applications

abstract:
  We have performed the harmonic analysis of the steady-state coherent
pulse-stacking process in a high-Q Fabry-Perot cavity. The expression for the
stacked pulse shape is obtained as a function of both the laser cavity and
pulse-stacking cavity parameters. We have also estimated the pulse power gains
attainable in the laser-optical system of NESTOR storage ring, which is under
development at Kharkov Institute of Physics and Technology. It is shown that
high power gains (~10000) can be, in principle, achieved in a cavity, formed
with low-absorption, high reflectivity (R~0.9999) mirrors, if the laser carrier
frequency will be matched to the second harmonic frequency of the
pulse-stacking cavity. This means a development of the sophisticated frequency
stabilization loop for maintaining the cavity length constant within a
sub-nanometer range.


title:
Forward-backward equations for nonlinear propagation in
  axially-invariant optical systems

abstract:
  We present a novel general framework to deal with forward and backward
components of the electromagnetic field in axially-invariant nonlinear optical
systems, which include those having any type of linear or nonlinear transverse
inhomogeneities. With a minimum amount of approximations, we obtain a system of
two first-order equations for forward and backward components explicitly
showing the nonlinear couplings among them. The modal approach used allows for
an effective reduction of the dimensionality of the original problem from 3+1
(three spatial dimensions plus one time dimension) to 1+1 (one spatial
dimension plus one frequency dimension). The new equations can be written in a
spinor Dirac-like form, out of which conserved quantities can be calculated in
an elegant manner. Finally, these new equations inherently incorporate
spatio-temporal couplings, so that they can be easily particularized to deal
with purely temporal or purely spatial effects. Nonlinear forward pulse
propagation and non-paraxial evolution of spatial structures are analyzed as
examples.


title: Electron Impact Ionization of Atoms

abstract:
  A one parameter expression for the single ionization cross-section of atoms
by electron impact is presented. Using this expression, the agreement obtained
with available experimental data for 45 elements (from ionization threshold up
to 200 eV ionizing electron energy) is shown to be comparable with (or better
than) that achieved using other multi-parameter approaches. We suggest that the
single parameter used here is associated with the effective reduction in the
number of equivalent electrons within a given shell accessible for ionization
by electron impact. We attribute this reduction effect to intra-shell shadowing
of part of the shell electrons by other electrons of the same shell. For atoms
with 2s^2p^i (i = 3,4,5,6) outer shell configurations we suggest also an
intershell shadowing effect. Finally, we discuss the possibility of a
meaningful contribution of inner shell ionization to the single ionization
cross-section due to various post-collision interactions. These interactions
may be responsible for decreasing the formation probability of doubly charged
ions.


title:
Electronic structure, vibrational stability, infra-red, and Raman
  spectra of B24N24 cages

abstract:
  We examine the vibrational stability of three candidate structures for the
B24N24 cage and report their infra-red (IR) and Raman spectra. The candidate
structures considered are a round cage with octahedral O symmetry, a cage with
S_4 symmetry that satisfies the isolated square rule, and a cage of S_8
symmetry, which combines the caps of the (4,4) nanotube, and contains two extra
squares and octagons. The calculations are performed within density functional
theory, at the all electron level, with large basis sets, and within the
generalized gradient approximation. The vertical ionization potential (VIP) and
static dipole polarizability are also reported. The
  S_4 and S_8 cages are energetically nearly degenerate and are favored over
the O cage which has six extra octagons and squares. The IR and Raman spectra
of the three clusters show notable differences providing thereby a way to
identify and possibly synthesize the cages.


title:
On the Equivalence of the Digital Waveguide and Finite Difference Time
  Domain Schemes

abstract:
  It is known that the digital waveguide (DW) method for solving the wave
equation numerically on a grid can be manipulated into the form of the standard
finite-difference time-domain (FDTD) method (also known as the ``leapfrog''
recursion). This paper derives a simple rule for going in the other direction,
that is, converting the state variables of the FDTD recursion to corresponding
wave variables in a DW simulation. Since boundary conditions and initial values
are more intuitively transparent in the DW formulation, the simple means of
converting back and forth can be useful in initializing and constructing
boundaries for FDTD simulations.


title:
Absorption of Scintillation Light in a 100 $\ell$ Liquid Xenon$\gamma$
  Ray Detector and Expected Detector Performance

abstract:
  An 800L liquid xenon scintillation $\gamma$ ray detector is being developed
for the MEG experiment which will search for $\mu^+\to\mathrm{e}^+\gamma$ decay
at the Paul Scherrer Institut. Absorption of scintillation light of xenon by
impurities might possibly limit the performance of such a detector. We used a
100L prototype with an active volume of 372x372x496 mm$^3$ to study the
scintillation light absorption. We have developed a method to evaluate the
light absorption, separately from elastic scattering of light, by measuring
cosmic rays and $\alpha$ sources. By using a suitable purification technique,
an absorption length longer than 100 cm has been achieved. The effects of the
light absorption on the energy resolution are estimated by Monte Carlo
simulation.


title: Linear Waves in Imperfect Relativistic MHD Fluid

abstract:
  Linear relativistic anisotropic magnetohydrodynamic waves are investigated
for an Imperfect fluid. Consideration is carried out for the plasma with finite
bulk viscosity. Conditions for growth and decay of these waves are obtained in
special cases of isotropy and Chew-Goldberger-Low (CGL) state.


title: Combinational processes in dense high-temperature plasmas

abstract:
  The dependence of the real and imaginary parts of the refractive index on the
dielectric capacity was obtained for different values of the nonideality
parameter, by the help of an ion-ion psevdopotential of fully ionized dense
high-temperature plasma, taking into account local fields, quantum and
collective effects.


title:
Path-integral Monte-Carlo simulations for electronic dynamics on
  molecular chains: I. Sequential hopping and super exchange

abstract:
  An improved real-time quantum Monte Carlo procedure is presented and applied
to describe the electronic transfer dynamics along molecular chains. The model
consists of discrete electronic sites coupled to a thermal environment which is
integrated out exactly within the path integral formulation. The approach is
numerically exact and its results reduce to known analytical findings (Marcus
theory, golden rule) in proper limits. Special attention is paid to the role of
superexchange and sequential hopping at lower temperatures in symmetric
donor-bridge-acceptor systems. In contrast to previous approximate studies,
superexchange turns out to play a significant role only for extremely high
lying bridges where the transfer is basically frozen or for extremely low
temperatures where for weaker dissipation a description in terms of rate
constants is no longer feasible. For bridges with increasing length an
algebraic decrease of the yield is found for short as well as for longer
bridges. The approach can be extended to electronic systems with more
complicated topologies including impurities and in presence of external time
dependent forces.


title:
The Eddy Experiment: GNSS-R speculometry for directional sea-roughness
  retrieval from low altitude aircraft

abstract:
  We report on the retrieval of directional sea surface roughness, in terms of
its full directional mean square slope (including direction and isotropy), from
Global Navigation Satellite System Reflections (GNSS-R) Delay-Doppler-Map (DDM)
data collected during an experimental flight at 1 km altitude. This study
emphasizes the utilization of the entire DDM to more precisely infer ocean
roughness directional parameters. In particular, we argue that the DDM exhibits
the impact of both roughness and scatterer velocity. Obtained estimates are
analyzed and compared to co-located Jason-1 measurements, ECMWF numerical
weather model outputs and optical data.