title:
Spontaneous-emission rates in finite photonic crystals of plane
  scatterers

abstract:
  The concept of a plane scatterer that was developed earlier for scalar waves
is generalized so that polarization of light is included. Starting from a
Lippmann-Schwinger formalism for vector waves, we show that the Green function
has to be regularized before T-matrices can be defined in a consistent way.
After the regularization, optical modes and Green functions are determined
exactly for finite structures built up of an arbitrary number of parallel
planes, at arbitrary positions, and where each plane can have different optical
properties. The model is applied to the special case of finite crystals
consisting of regularly spaced identical planes, where analytical methods can
be taken further and only light numerical tasks remain. The formalism is used
to calculate position- and orientation-dependent spontaneous-emission rates
inside and near the finite photonic crystals. The results show that emission
rates and reflection properties can differ strongly for scalar and for vector
waves. The finite size of the crystal influences the emission rates. For
parallel dipoles close to a plane, emission into guided modes gives rise to a
peak in the frequency-dependent emission rate.


title:
Capture into resonance in dynamics of a classical hydrogen atom in an
  oscillating electric field

abstract:
  We consider a classical hydrogen atom in a linearly polarized electric field
of slow changing frequency. When the system passes through a resonance between
the driving frequency and the Kepler frequency of the electron's motion, a
capture into the resonance can occur. We study this phenomenon in the case of
2:1 resonance and show that the capture results in growth of the eccentricity
of the electron's orbit. The capture probability for various initial values of
the eccentricity is defined and calculated.


title:
System for Nuclear Waste Transmutation Driven by Target-Distributed
  Accelerators

abstract:
  A design concept and characteristics for an epithermal breeder controlled by
variable feedback and external neutron source intensity are presented. By
replacing the control rods with neutron sources, we could improve safety and
perform radioactive waste burning in high flux subcritical reactors (HFSR). To
increase neutron source intensity the HFSR is divided into two zones: a booster
and a blanket operating with solid and liquid fuels. Use of a liquid actinide
fuel permits transport of the delayed-neutron emitters from the blanket to the
booster where they can provide additional neutrons or all the necessary
excitation. With blanket and booster multiplication factors of k=0.95 and 0.98,
respectively, an external photoneutron source rate of at least 10.sup.15 n/s
(electron beam power 2.5MW) is needed to control the HFSR that produces 300MWt.
An inexpensive method of obtaining large neutron fluxes is target-distributed
accelerators (TDA), in which a fission electrical cell (FEC) compensates for
lost beam energy in the thin photon production targets. The FEC is essentially
a high-voltage power source that directly converts the kinetic energy of the
fission fragments into electrical potential of about 2 MV.


title:
Observation of Large Atomic-Recoil Induced Asymmetries in Cold Atom
  Spectroscopy

abstract:
  The atomic recoil effect leads to large (25 %) asymmetries in simple
spectroscopic investigations of Ca atoms that have been laser-cooled to 10
microkelvin. Starting with spectra from the more familiar Doppler-broadened
domain, we show how the fundamental asymmetry between absorption and stimulated
emission of light manifests itself when shorter spectroscopic pulses lead to
the Fourier transform regime. These effects occur on frequency scales much
larger than the size of the recoil shift itself, and have not been observed
before in saturation spectroscopy. These results are relevant to
state-of-the-art optical atomic clocks based on freely expanding neutral atoms.


title:
Pouzyry: a novel class of algorithms for restoring a function from a
  random sample

abstract:
  A novel class of algorithms for restoring a function from a random sample is
based on the concept of weak convergence, borrows algorithmic solutions from
the Optimal Jet Finder (hep-ph/0301185), offers a considerable algorithmic
flexibility, is applicable to non-positive functions, is insensitive to the
choice of coordinate axes. A first implementation demonstrates feasibility of
the approach.


title:
Existence of Dynamical Scaling in the Temporal Signal of Time Projection
  Chamber

abstract:
  The temporal signals from a large gas detector may show dynamical scaling due
to many correlated space points created by the charged particles while passing
through the tracking medium. This has been demonstrated through simulation
using realistic parameters of a Time Projection Chamber (TPC) being fabricated
to be used in ALICE collider experiment at CERN. An interesting aspect of this
dynamical behavior is the existence of an universal scaling which does not
depend on the multiplicity of the collision. This aspect can be utilised
further to study physics at the device level and also for the online monitoring
of certain physical observables including electronics noise which are a few
crucial parameters for the optimal TPC performance.


title:
Photofragmentation of the H_3 molecule, including Jahn-Teller coupling
  effects

abstract:
  We have developed a theoretical method for interpretation of photoionization
experiments with the H_3 molecule. In the present study we give a detailed
description of the method, which combines multichannel quantum defect theory,
the adiabatic hyperspherical approach, and the techniques of outgoing Siegert
pseudostates. The present method accounts for vibrational and rotation
excitations of the molecule, deals with all symmetry restrictions imposed by
the geometry of the molecule, including vibrational, rotational, electronic and
nuclear spin symmetries. The method was recently applied to treat dissociative
recombination of the H_3^+ ion. Since H_3^+ dissociative recombination has been
a controversial problem, the present study also allows us to test the method on
the process of photoionization, which is understood better than dissociative
recombination. Good agreement with two photoionization experiments is obtained.


title:
Nuclear Waste Transmutation in Subcritical Reactors Driven by
  Target-Distributed Accelerators

abstract:
  A radioactive waste transmutation system based extensively on existing
nuclear power technology is presented. By replacing the control rods with
neutron sources, we could maintain good power distribution and perform
long-lived waste burning in high flux subcritical reactors. The design is based
on a small pressurized water reactor, fission electric cell (FEC),
target-distributed accelerator (TDA) and power monitoring system with in-core
gamma-ray detectors, now under development in several countries. The TDA, in
which an FEC electric field compensates for lost beam energy in the target,
offers a new approach to obtain large neutron fluxes. The analysis takes into
consideration a wide range of TDA design aspects including the wave model of
observed relativistic phenomena, in-core microwave power source, the FEC with a
multistage collector (anode) and layered cathode.


title: What happened to modern physics?

abstract:
  Relativity, Quantum Mechanics and Chaos theory are three of the most
significant scientific advances of the 20th Century - each fundamentally
changing our understanding of the physical universe. The authors ask why the UK
National Curriculum in science almost entirely ignores them. Children and young
people regularly come into contact with the language, concepts and implications
of these theories through the media and through new technologies, and they are
the basis of many contemporary scientific and technological developments. There
is surely, therefore, an urgent need to include the concepts of '20th Century
physics' within the curriculum.


title:
Lorentz Electrodynamics, Matter/Antimatter Cosmology and Astroparticle
  Physics

abstract:
  It is shown that the noncommutative Lorentz metric satisfies so-called
nonpropagating waves. The long-range forces are obtained as a description of
these wave motions. It leads to the natural introduction of the field values
(group velocity and intensity of de Broglie waves) into Maxwell's equations and
antimatter into Newtonian mechanics. One of the early predictions of the wave
theory was existence of antiparticles (modes with the negative group velocity).
They are attracted by ordinary matter, but repulse ordinary matter and each
other gravitationally. The interaction between the two types of matter might
lead to the expansion of the universe and maintain the energy reservoir for
cosmic sources of intense radiation.


title: The Domino Effect

abstract:
  The physics of a row of toppling dominoes is discussed. In particular the
forces between the falling dominoes are analyzed and with this knowledge, the
effect of friction has been incorporated. A set of limiting situations is
discussed in detail, such as the limit of thin dominoes, which allows a full
and explicit analytical solution. The propagation speed of the domino effect is
calculated for various spatial separations. Also a formula is given, which
gives explicitly the main dependence of the speed as function of the domino
width, height and interspacing.


title: Anomalous cooling of the parallel velocity in seeded beams

abstract:
  We have measured the parallel velocity distribution of a lithium supersonic
beam produced by seeding lithium in argon. The parallel temperature for lithium
is considerably lower than the calculated parallel temperature of the argon
carrier gas. We have extended the theory of supersonic cooling to calculate the
parallel temperature of the seeded gas, in the limit of high dilution. The
theoretical result thus obtained is in good agreement with ourobservations.


title: Continuum model for Couette-Poiseuille flow in a drag molecular pump

abstract:
  A continuum one-dimensional model of the plane Couette-Poiseuille flow is
developed to describe the pressure distribution in a drag stage of molecular
pump of either the Gaede or Holweck type. In spite of its simplicity and
approximate nature the model provides a good qualitative representation of the
drag pump operation in the whole range of the regimes from the continuum to
free molecular ones.


title: Spatial Coherence of Synchrotron Radiation

abstract:
  Theory and measurement of spatial coherence of synchrotron radiation beams
are briefly reviewed. Emphasis is given to simple relationships between
electron beam characteristics and far field properties of the light beam.


title: Ion Transit Pathways and Gating in ClC Chloride Channels

abstract:
  ClC chloride channels possess a homodimeric structure in which each monomer
contains an independent chloride ion pathway. ClC channel gating is regulated
by chloride ion concentration, pH, and voltage. Based on structural and
physiological evidence, it has been proposed that a glutamate residue on the
extracellular end of the selectivity filter acts as a fast gate. We utilize a
new search algorithm which incorporates electrostatic information to explore
the ion transit pathways through wild-type and mutant bacterial ClC channels.
Examination of the chloride ion permeation pathways supports the proposed
important role of the glutamate residue in gating. An external chloride binding
site previously postulated in physiological experiments is located near a
conserved basic residue adjacent to the gate. In addition, access pathways are
found for proton migration to the gate, enabling pH control at hyperpolarized
membrane potentials. A chloride ion in the selectivity filter is required for
the pH-dependent gating mechanism.


title:
Comment on "On the negative value of dielectric permittivity of the
  water surface layer" [Appl. Phys. Lett. 83, 4506 (2003)]

abstract:
  The recent interpretation of the positive resonance frequency shift in
dielectric resonators loaded by water is reviewed. Instead of the invoked
negative dielectric constant of water surface layer, it is demonstrated that
the experimental results are fully reproduced by taking into account the
dielectric losses of the sample.


title:
Enhanced hard X-ray emission from femtosecond laser irradiated
  microdroplets

abstract:
  We make a comparative study of hard x-ray emission from 15 $\mu$m methanol
microdroplets and a plain slab target of similar atomic composition at similar
laser intensities. The hard X-ray yield from droplet plasmas is $\simeq$ 35
times more than that obtained from solid plasmas. A prepulse that is about 10ns
and about 5% of the main pulse is essential for hard x-ray generation from the
droplets.
  A hot electron temperature of 36 keV is measured from the droplets at
8$\times10^{14}$ W cm$^{-2}$; three times higher intensity is needed to obtain
similar hot electron temperature from solid plasmas with similar composition.
We use 1D PIC simulation to obtain qualitative correlation to the experimental
observations.


title:
Non-reciprocal optical reflection from a bidimensional array of
  subwavelength holes in a metallic film

abstract:
  Using simulations and theoretical arguments we investigate the specular
reflection of a perforated gold film deposited on a glass substrate. A square
lattice of cylindrical holes is assumed to produce the periodic lateral
corrugation needed to hybridize the surface plasmons with radiative states. It
is shown that, contrasting transmission approaches, a knowledge of the
reflection on either side of the film provides separate information on the
gold-vacuum surface plasmons and on the gold-glass interface plasmons. Recent
experimental data on a specific implementation of this system are reexamined;
these show a good agreement between the measured reflections and the
simulations in both directions of incident wave probes. This confirms the
importance of taking into account the reflection asymmetry in the far-field
assessment of surface plasmons properties.


title:
Angular momentum conservative algorithm of collisional process in DSMC
  method

abstract:
  The traditional algorithm of collisional process in DSMC method, used for
calculation of velocities of molecules after collision, is based on the
conservation laws for linear momentum and total energy. This algorithm does not
provide conservation of angular momentum with respect to some axis, but for
non-rotating flow this circumstance is insignificant, since the mean value of
angular momentum of such kind of flow is equal to zero. The situation changes
for axisymmetric flow with rotation. In this case the traditional procedure
leads to some internal source or sink of angular momentum that may distort the
flowfield. In the paper the discussed effect is recognized and investigated.
The angular momentum conservative (AMC) algorithm of collisional process is
proposed.


title:
Similarity of skeletal structures in laboratory and space and the
  probable role of self-assembling of a fractal dust in fusion devices

abstract:
  This papers briefly reviews the progress in studying the long-lived
filamentary structures of a skeletal form (namely, tubules and cartwheels, and
their simple combinations) in electric discharges in various fusion devices.
These include fast Z-pinch, tokamak and laser produced plasmas. We also report
on the results of a search for the phenomenon of skeletal structures --
formerly revealed in laboratory data from fusion devices -- at larger and much
larger length scales, including the powerful electromagnetic phenomena in the
Earth atmosphere and cosmic space. It is found that the similarity of, and a
trend toward self-similarity in, the observed skeletal structures more or less
uniformly covers the range 10^{-5} cm - 10^{23} cm. These evidences suggest all
these skeletal structures, similarly to skeletons in the particles of dust and
hail, to possess a fractal condensed matter of particular topology of the
fractal. The probable role of the phenomenon of self-assembling of a fractal
dust in fusion devices and outside the fusion is discussed briefly.


title: Some features of the flow in the Holweck pump

abstract:
  Numerical algorithm for direct simulation of the gas flow in the Holweck pump
is developed. The results illustrating the important features of the flow in
the pump are reported. An attention is paid to the problem of the pump design
optimization.


title: Lattice for Longitudinal Low-Beta

abstract:
  The guidelines for a phi-factory at very high luminosity are described. A
preliminary design for a double ring collider, DAPHNE-II, is presented,
fulfilling the requirements of luminosity of the order of 10^34 cm-2sec-1


title: Trends in Pixel Detectors: Tracking and Imaging

abstract:
  For large scale applications, hybrid pixel detectors, in which sensor and
read-out IC are separate entities, constitute the state of the art in pixel
detector technology to date. They have been developed and start to be used as
tracking detectors and also imaging devices in radiography, autoradiography,
protein crystallography and in X-ray astronomy. A number of trends and
possibilities for future applications in these fields with improved
performance, less material, high read-out speed, large radiation tolerance, and
potential off-the-shelf availability have appeared and are momentarily matured.
Among them are monolithic or semi-monolithic approaches which do not require
complicated hybridization but come as single sensor/IC entities. Most of these
are presently still in the development phase waiting to be used as detectors in
experiments. The present state in pixel detector development including hybrid
and (semi-)monolithic pixel techniques and their suitability for particle
detection and for imaging, is reviewed.


title: Upgrades of Particle Factories

abstract:
  Recently the luminosity frontier has been raised by the Beauty factories.
Higher precision measurements at the energies between the PHI and the Beauty
are being projected, and the corresponding increase of luminosity by orders of
magnitude is being faced by the accelerator community. The main upgrades and
plans in the factories presently in operation or construction around the world
are here summarized.


title: Dark Energy, Gravitation and Electromagnetism

abstract:
  In the context of the fact that the existence of dark energy causing the
accelerated expansion of the universe has been confirmed by the WMAP and the
Sloan Digital Sky Survey, we re-examine gravitation itself, starting with the
formulation of Sakharov and show that it is possible to obtain gravitation in
terms of the electromagnetic charge of elementary particles, once the ZPF and
its effects at the Compton scale are taken into account.


title: La peche dans les trous noires

abstract:
  The problem of a thread whose extremity is beyond the Schwarzschild horizon
is discussed.
  We present a new coordinate system allowing to write the Schwarzschild metric
in all regions.
  The system of coordinates introduced appears to be particulary indicated to
study the passage of extended bodies throuth the Schwarzschild horizon,as it is
the case of a thread that continues to attach a fisherman to a fish that
entered a black hole.


title:
Detection of antihydrogen annihilations with a Si-micro-strip and pure
  CsI detector

abstract:
  In 2002, the ATHENA collaboration reported the creation and detection of cold
(~15 K) antihydrogen atoms [1]. The observation was based on the complete
reconstruction of antihydrogen annihilations, simultaneous and spatially
correlated annihilations of an antiproton and a positron. Annihilation
byproducts are measured with a cylindrically symmetric detector system
consisting of two layers of double sided Si-micro-strip modules that are
surrounded by 16 rows of 12 pure CsI crystals (13 x 17.5 x 17 mm^3). This paper
gives a brief overview of the experiment, the detector system, and event
reconstruction.
  Reference 1. M. Amoretti et al., Nature 419, 456 (2002).


title: A Didactic Approach to Linear Waves in the Ocean

abstract:
  The general equations of motion for ocean dynamics are presented and the
waves supported by the (inviscid, unforced) linearized system with respect to a
state of rest are derived. The linearized dynamics sustains one zero frequency
mode (called buoyancy mode) in which salinity and temperature rearrange in such
a way that seawater density does not change. Five nonzero frequency modes (two
acoustic modes, two inertia--gravity or Poincar\'{e} modes, and one planetary
or Rossby mode) are also sustained by the linearized dynamics, which satisfy an
asymptotic general dispersion relation. The most usual approximations made in
physical oceanography (namely incompressibility, Boussinesq, hydrostatic, and
quasigeostrophic) are also consider, and their implications in the reduction of
degrees of freedom (number of independent dynamical fields or prognostic
equations) of, and compatible waves with, the linearized governing equations
are particularly discussed and emphasized.


title: Thermodynamic Sampling of Molecular Conformations

abstract:
  Torsional-space Monte Carlo simulations of flexible molecules are usually
based on the assumption that all values of dihedral angles have equal
probability in the absence of atomic interactions. In the present paper it is
shown that this assumption is not valid. Thermodynamic sampling using dihedral
angles or other internal coordinates has to account for both the correct metric
in conformational space and the conformation-dependence of the moment of
inertia tensor. Metric and moment of inertia terms appear as
conformation-dependent factors in the partition function and are obtained by
proper separation of internal and rotational degrees of freedom. The importance
of both factors is discussed for a number of short peptides as well as for the
folded and unfolded states of a protein. It is concluded that thermodynamic
Monte Carlo simulations of protein folding that neglect these correction
factors tend to underestimate the stability of the folded state.


title: Accelerator Physics Issues in the Bepcii

abstract:
  The Beijing Electron-Positron Collider (BEPC) has been running for both high
energy physics (HEP) and synchrotron radiation (SR) researches since 1989. Good
performance of BEPC accomplishes a lot of achievements in the tau-charm region
over the past decade, and in many fields of SR applications as well. As an
upgrading scheme from BEPC, the BEPCII project was approved by the Chinese
government in the early time of this year, with a micro-beta scheme and
multi-bunch collision in a doublering machine installed in the current BEPC
tunnel. The design work of the BEPCII is being carried on. This paper will
describe the main progresses on the design of the BEPCII in the field of
accelerator physics.


title: Neural Network Approach to Study of Langmuir Layers at the Water Surface

abstract:
  The structure of the layers of a phthalocyanines is studied through a
measurement of surface pressure-area isotherms at various initial surface
concentrations of the spreaded compound. Layer characteristics are determined
from experimental data by replotting the isotherms in accordance with M. Volmer
s equation. Neural networks taught on approximations of the isoterms. The
method is compared with the traditional least square one. Another task for NN
is a forecast of main characteristics of the layers.


title:
Frequency-domain "single-shot" (FDSS) ultrafast transient absorption
  spectroscopy using compressed laser pulses. Part I. Basic treatment

abstract:
  Single-shot ultrafast absorbance spectroscopy based on the frequency encoding
of the kinetics is analyzed theoretically and implemented experimentally. The
kinetics are sampled in the frequency domain using linearly chirped, amplified
33 fs FWHM pulses derived from a Ti:sapphire laser. A variable length grating
pair compressor is used to achieve the time resolution of 500-1000 channels per
a 2-to-160 ps window with sensitivity > 5x10-4. In terms of the acquisition
time, FDSS has an advantage over the pump-probe spectroscopy in a situation
when the "noise" is dominated by amplitude variations of the signal, due to the
pump and flow instabilities. The possibilities of FDSS are illustrated with the
kinetics obtained in multiphoton ionization of water and aqueous iodide and
one-photon excitation of polycrystalline ZnSe and thin-film amorphous Si:H.
Unlike other "single-shot" techniques, FDSS can be implemented for fluid
samples flowing in a high-speed jet and for thin solid samples that exhibit
interference fringes; no a priori knowledge of the excitation profile of the
pump across the beam is needed. 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 pattern
is unique and can be used to determine the complex dielectric function of the
photogenerated species.


title:
Frequency-domain "single-shot" (FDSS) ultrafast transient absorption
  spectroscopy using compressed laser pulses. Part II. Supplemetary Material

abstract:
  Single-shot ultrafast absorbance spectroscopy based on the frequency encoding
of the kinetics is analyzed theoretically and implemented experimentally. In
Part II of the series, arbitrary thickness sample is analysed theroretically.
The model is then used to simulate the results for a-Si:H films.


title: 1D and 2D optical lattices on a chip for quantum computing

abstract:
  We propose a way to make arrays of optical frequency dipole-force microtraps
for cold atoms above a dielectric substrate. Traps are nodes in the evanescent
wave fields above an optical waveguide resulting from interference of different
waveguide modes. The traps have features sought in developing neutral atom
based architectures for quantum computing: ~ 1 mW of laser power yields very
tight traps 150 nm above a waveguide with trap vibrational frequencies ~ 1 MHz
and vibrational ground state sizes ~ 10 nm. The arrays are scalable and allow
addressing of individual sites for quantum logic operations.


title: Asymmetric Errors

abstract:
  Errors quoted on results are often given in asymmetric form. An account is
given of the two ways these can arise in an analysis, and the combination of
asymmetric errors is discussed. It is shown that the usual method has no basis
and is indeed wrong. For asymmetric systematic errors, a consistent method is
given, with detailed examples. For asymmetric statistical errors a general
approach is outlined.


title: Relaxation effect and radiative corrections in many-electron atoms

abstract:
  We illuminate the importance of a self-consistent many-body treatment in
calculations of vacuum polarization corrections to the energies of atomic
orbitals in many-electron atoms. Including vacuum polarization in the atomic
Hamiltonian causes a substantial re-adjustment (relaxation) of the
electrostatic self-consistent field. The induced change in the electrostatic
energies is substantial for states with the orbital angular momentum $l &;gt;
0$. For such orbitals, the relaxation mechanism determines the sign and even
the order of magnitude of the total vacuum polarization correction. This
relaxation mechanism is illustrated with numerical results for the Cs atom.


title: Still Shrouded in Mystery: The Photon in 1925

abstract:
  We present a translation of Albert Einstein's Rio de Janeiro manuscript on
light quanta. In it, Einstein evaluates the Bohr-Kramers-Slater refutation of
light quanta, which was concurrently the subject of intense empirical scrutiny
on two continents. Written shortly before Heisenberg's discovery of quantum
mechanics, the manuscript represents Einstein's last published remark on the
constitution of light in the historical period known as the old quantum theory.
It crystallizes the fact that by 1925 the photon concept was still incomplete,
even as the corpuscular properties of light gained decisive empirical
confirmation.


title: Comments on Likelihood fits with variable resolution

abstract:
  Unbinned likelihood fits are frequent in Physics, and often involve complex
functions with several components. We discuss the potential pitfalls of
situations where the templates used in the fit are not fixed but depend on the
event observables, as it happens when the resolution of the measurement is
event--dependent, and the procedure to avoid them.


title: The problem with the Brier score

abstract:
  The Brier score is frequently used by meteorologists to measure the skill of
binary probabilistic forecasts. We show, however, that in simple idealised
cases it gives counterintuitive results. We advocate the use of an alternative
measure that has a more compelling intuitive justification.


title: Gravitation, the 'Dark Matter' Effect and the Fine Structure Constant

abstract:
  Gravitational anomalies such as the mine/borehole g anomaly, the
near-flatness of the spiral galaxy rotation-velocity curves, currently
interpreted as a `dark matter' effect, the absence of that effect in ordinary
elliptical galaxies, and the ongoing problems in accurately determining
Newton's gravitational constant G_N are explained by a generalisation of the
Newtonian theory of gravity to a fluid-flow formalism with one new
dimensionless constant. By analysing the borehole data this constant is shown
to be the fine structure constant alpha=1/137. The spiral galaxy `dark matter'
effect and the globular cluster `black hole' masses are then correctly
predicted. This formalism also explains the cause of the long-standing
uncertainties in G_N and leads to the introduction of a fundamental
gravitational constant G not = G_N with value G=(6.6526 +/- 0.013)x 10^-11
m^3s^{-2}kg^{-1}. The occurrence of alpha implies that space has a quantum
structure, and we have the first evidence of quantum gravity effects.


title: Compton shift and de Broglie frequency

abstract:
  Compton scattering is usually explained in terms of the relativistic mass and
momentum. Here, a mathematically equivalent and simple non-relativistic
interpretation shows that the Compton frequency shift is equal to the de
Broglie frequency associated with the moving charged particle (e.g., an
electron). In this work, the moving electron is considered as a particle and
the electromagnetic energy associated with it is shown to be proportional to
the de Broglie frequency. This energy is released when its motion is arrested,
as for example on a diffraction screen, where it causes the observed
interfernce patterns. Thus, electrons transport electromagnetic energy from a
source to a sink.


title: Anomalous magnetic moment and Compton wavelength

abstract:
  The relativistic and quantum theoretical explanations of the magnetic moment
anomaly of the electron (or proton) show that it is a complicated function of
the fine structure constant. In this work, a simple non-relativistic approach
shows that the translational motion of the particle during its spin is
responsible for the observed effects.


title: Compton wavelength, Bohr radius, Balmer's formula and g-factors

abstract:
  The Balmer formula for the spectrum of atomic hydrogen is shown to be
analogous to that in Compton effect and is written in terms of the difference
between the absorbed and emitted wavelengths. The g-factors come into play when
the atom is subjected to disturbances (like changes in the magnetic and
electric fields), and the electron and proton get displaced from their fixed
positions giving rise to Zeeman effect, Stark effect, etc.


title: Coherency is the ether of XXI century

abstract:
  The concept of coherent states in explanation of a nature of nonlinear
phenomena in optics will be inevitably replaced by the concept of inequality of
forward and reversed transitions.


title: Making sense of studying physics

abstract:
  With an investigation into how students in a physics Master of science
program make sense of their whole first year study experience in one of the
years following a programme reform, we try to offer insights and advice to
consider when involved in similar changes. We conclude and argue that by trying
to support the students' in making sense of their studying in terms of physics
and empowering them in their understanding of the nature of physics and their
study situation, both the potential for productive, meaningful and positive
learning of physics as something which is relevant in the students life, and
the way in which the students analyse and make sense of things they encounter,
both physically and academically, are advanced.


title: Learning-focuses in physics simulation learning situations

abstract:
  This is a report on a qualitative study of students' learning where a physics
computer simulation session is used to supplement lectures on the topic.
Drawing on phenomenography as the analytical framework, the students'
learning-focuses were analysed. The result is a description of four distinctly
different learning-focuses that emerged when the students involved in the study
interacted with the computer simulations. These learning-focuses were then
analysed in terms of the level of interaction, the nature of physics knowledge
and views of learning experienced by the students. These results were then used
to identify advantages and disadvantages of learning through interaction with
simulations.


title:
Fano-type interpretation of red shifts and red tails in hole array
  transmission spectra

abstract:
  We present a unifying point of view which allows to understand spectral
features reported in recent experiments with two-dimensional arrays of
subwavelength holes in metal films. We develop a Fano analysis of the related
scattering problem by distinguishing two interfering contributions to the
transmission process, namely a non-resonant contribution (direct scattering)
and a resonant contribution (surface plasmon excitation). The introduction of a
coupling strength between these two contributions naturally induces resonance
shifts and asymmetry of profiles which satisfy simple scaling relations. We
also report an experiment to confirm this analysis.


title: Narrow Line Cooling: Finite Photon Recoil Dynamics

abstract:
  We present an extensive study of the unique thermal and mechanical dynamics
for narrow-line cooling on the 1S0 - 3P1 88Sr transition. For negative
detuning, trap dynamics reveal a transition from the semiclassical regime to
the photon-recoil-dominated quantum regime, yielding an absolute minima in the
equilibrium temperature below the single-photon recoil limit. For positive
detuning, the cloud divides into discrete momentum packets whose alignment
mimics lattice points on a face-centered-cubic crystal. This novel behavior
arises from velocity selection and "positive feedback" acceleration due to a
finite number of photon recoils. Cooling is achieved with blue-detuned light
around a velocity where gravity balances the radiative force.


title: On final states of 2D decaying turbulence

abstract:
  Numerical and analytical studies of "final states" of two-dimensional (2D)
decaying turbulence are reported. The first part of this work is trying to give
a definition for final states of 2D decaying turbulence. Although the
functional relation of $\omega-\psi$ is frequently used as the characterization
of those "final states," it is just a sufficient but not necessary condition so
it is not proper to be used as the definition. It is found the way through the
value of the effective area S covered by the scatter $\omega-\psi$ plot, which
is initially suggested by Read, is more general, and more suitable for the
definition. Based on this concept, we gave out a definition that can cover all
existing results in late states of decaying 2D flows, including some weird
double-valued $\omega-\psi$ scatter plots that can not be explained before. The
rest part of the paper is trying to further investigate 2D decaying turbulence
with the assistance of our new definition. Some new numerical results, which
lead to "bar" final states and further verify the predictive ability of
statistical mechanics [2], are reported. It is realized that some simulations
with narrow-band energy spectral initial conditions, which can be called
"turbulence" doubtfully, lead to some final states that can not be very well
explained by the statistical theory (in the meanwhile, they are still in the
scope of our new definition of the "final state"). For those simulations with
initial conditions of broadband energy spectra that lead to the famous dipole,
we give out a mathematical re-interpreting for the so-called sin-hyperbolic
("sinh") $\omega-\psi$ scatter plot in final states. We suggest the term "sinh"
here should be replaced by "sinh-like." The corresponding physical meaning of
this re-interpreting will also be discussed.


title:
Recombination of Geminate (OH,eaq-) Pairs in Concentrated Alkaline
  Solutions: Lack of Evidence For Hydroxyl Radical Deprotonation

abstract:
  Picosecond dynamics of hydrated electrons and hydroxyl radicals generated in
200 nm photodissociation of aqueous hydroxide and 400 nm (3-photon) ionization
of water in concentrated alkaline solutions were obtained. No deprotonation of
hydroxyl radicals was observed on sub-nanosecond time scale, even in 1-10 M KOH
solutions. This result is completely at odds with the kinetic data for
deprotonation of OH radical in dilute alkaline solutions. We suggest that the
deprotonation of hydroxyl radical is slowed down dramatically in concentrated
alkaline solutions.


title:
Multimer Radical Ions and Electron/Hole Localization in Polyatomic
  Molecular Liquids: A critical review

abstract:
  While ionization of some polyatomic molecular liquids (such as water and
aliphatic alcohols) yields so-called "solvated electrons" in which the excess
electron density is localized in the interstices between the solvent molecules,
most organic and inorganic liquids yield radical anions and cations in which
the electron and spin densities reside on the solvent molecule or, more
commonly, a group of such molecules. The resulting multimer ions have many
unusual properties, such as high rates of diffusive hopping. The "solvated
electron" can be regarded as a variant of a multimer radical anion in which the
charge, while perturbing the solvent molecules, mainly resides in the space
between these molecules. We give several examples of less known modes for
electron localization in liquids that yield multimer radical anions (such as
C6F6, benzene, acetonitrile, carbon disulfide and dioxide, etc.) and holes
localization in liquids that yield multimer radical cations (such as
cycloalkanes). Current understanding of the reaction properties for these
high-mobility solvent radical anions and cations is discussed.


title:
Efficient, rapid one-electron photooxidation of chemisorbed polyhydroxyl
  alcohols and carbohydrates by TiO2 nanoparticles in an aqueous solution

abstract:
  Time-resolved transient absorption spectroscopy has been used to study
nanosecond and sub-microsecond electron dynamics in aqueous anatase
nanoparticles in the presence of hole scavengers: chemisorbed polyols and
carbohydrates. These polyhydroxylated compounds are rapidly oxidized by the
holes; 50-60% of these holes are scavenged within the duration of 355 nm
excitation laser pulse. The scavenging efficiency rapidly increases with the
number of anchoring hydroxyl groups and varies considerably as a function of
the carbohydrate structure. A specific binding site for the polyols and
carbohydrates is suggested that involves an octahedral Ti atom chelated by the
poly-OH ligand. This mode of binding accounts for the depletion of
undercoordinated Ti atoms observed in the XANES spectra of polyol coated
nanoparticles. We suggest that these binding sites trap a substantial fraction
of holes before the latter descend to surface traps and/or recombine with free
electrons. The resulting oxygen hole center rapidly loses a CH proton to the
environment, yielding a metastable C-centered radical.


title: Inconsistencies between lifetime and polarizability measurements in Cs

abstract:
  Electric-dipole matrix elements for 6p-nd, n=5, 6, 7 transitions in cesium
are calculated using a relativistic all-order method. The resulting matrix
elements are used to evaluate 5d lifetimes and 6p polarizabilities. The data
are compared with experimental lifetime and polarizability measurements made by
different groups. Domination of the 6p scalar polarizabilities by 5d-6p dipole
matrix elements facilitates an exacting consistency check of 5d lifetime and 6p
polarizability data. Values of 5d-6p matrix elements obtained from experimental
5d lifetime data are found to be inconsistent with those inferred from 6p
polarizabilities derived from experimental Stark shift data. Our ab initio
calculated 6p polarizabilities agree well with experimental determinations.


title:
Semi-empirical boundary conditions for strong evaporation of a
  polyatomic gas

abstract:
  Semi-empirical procedure of obtaining the boundary conditions for strong
evaporation of a polyatomic gas from a plane surface is proposed. The procedure
is based on specifying the dependencies of specific momentum and enthalpy of
the flow from the gas flow rate. The latter are derived from the analysis of
the available data concerning the evaporation of polyatomic and monatomic
gases. The procedure predicts the exactly sonic terminal velocity of the flow
and leads to some corrections of existing boundary conditions in transonic
region. Thus, for j = 2 and sonic flow the corrections for pressure,
temperature and fraction of back-scattered molecules are about 0.7%, -3% and
-8%.


title: Following Weyl on Quantum Mechanics: the contribution of Ettore Majorana

abstract:
  After a quick historical account of the introduction of the group-theoretical
description of Quantum Mechanics in terms of symmetries, as proposed by Weyl,
we examine some unpublished papers by Ettore Majorana. Remarkable results
achieved by him in frontier research topics as well as in physics teaching
point out that the Italian physicist can be well considered as a follower of
Weyl in his reformulation of Quantum Mechanics.

categories: physics.hist-ph hep-ph hep-th physics.gen-ph


title: Inaccurate use of asymptotic formulas

abstract:
  The asymptotic form of the plane wave decomposition into spherical waves,
which is used to express the scattering amplitude in terms of phase shifts, is
incorrect. We explain why and show how to circumvent the mathematical
inconsistency.


title:
On the CODATA Recommended Values of the Fundamental Physical Constants:
  V3.2(1998) & V4.0(2002)

abstract:
  With the help of special program package PAREVAL designed in {\sl
Mathematica} system we reproduce values of basic fundamental physical constants
obtained by NIST and recommended by CODATA for international usage since 1998.
In our adjustment we use the input data and methods published by NIST in 1998.
It is shown, that the detected earlier inaccuracy of published by NIST
correlations (that made the NIST 1998&2002 results doubtful) are, most
probably, due to inadmissible independent rounding. The simple estimate of the
critical numbers of decimal digits in the independently rounded correlation
coefficients is obtained. Further independent rounding of ``critically
rounded'' correlations can lead to the non positive semi definite correlation
matrices and hence is inadmissable. It is demonstrated by a few examples that
the poor presentation of the correlated random quantities in the scientific
literature is a common bad practice and is argued (once again) that the common
standard for presentation numerical values of correlated quantities in
publications and sites is urgently and badly needed.


title:
Velocity excitations and impulse responses of strings - Aspects of
  continuous and discrete models

abstract:
  This paper discusses aspects of the second order hyperbolic partial
differential equation associated with the ideal lossless string under tension
and it's relationship to two discrete models. These models are finite
differencing in the time domain and digital waveguide models. It is known from
the theory of partial differential operators that in general one has to expect
the string to accumulate displacement as response to impulsive excitations.
Discrete models should be expected to display comparable behavior. As a result
it is shown that impulsive propagations can be interpreted as the difference of
step functions and hence how the impulsive response can be seen as one case of
the general integrating behavior of the string. Impulsive propagations come
about in situations of time-symmetry whereas step-function occur as a result of
time-asymmetry. The difference between the physical stability of the wave
equation, which allows for unbounded growth in displacement, and computational
stability, that requires bounded growth, is derived.


title: Statistical Physics in Meteorology

abstract:
  Various aspects of modern statistical physics and meteorology can be tied
together. The historical importance of the University of Wroclaw in the field
of meteorology is first pointed out. Next, some basic difference about time and
space scales between meteorology and climatology is outlined. The nature and
role of clouds both from a geometric and thermal point of view are recalled.
Recent studies of scaling laws for atmospheric variables are mentioned, like
studies on cirrus ice content, brightness temperature, liquid water path
fluctuations, cloud base height fluctuations, .... Technical time series
analysis approaches based on modern statistical physics considerations are
outlined.


title: Expressing Maxwell's equations independently of the unit system

abstract:
  A procedure to teach Electrodynamics independently of unit systems is
presented and compared with some of those given in physics literature.


title: The ATLAS Pixel Detector

abstract:
  The ATLAS Pixel Detector is the innermost layer of the ATLAS tracking system
and will contribute significantly to the ATLAS track and vertex reconstruction.
The detector consists of identical sensor-chip-hybrid modules, arranged in
three barrels in the centre and three disks on either side for the forward
region.
  The position of the Pixel Detector near the interaction point requires
excellent radiation hardness, mechanical and thermal robustness, good long-term
stability, all combined with a low material budget. The detector layout,
results from final prototyping and the status of production are presented.


title:
Peculiarities of localization of several sonoluminescent bubbles in
  spherical resonators

abstract:
  Experiments on generation of 1, 2, 4, and 6 sonoluminescent bubbles in water
with an external ultrasound source in an acoustic sphere resonator with glass
walls have been carried out. Theoretical examination has shown that the
observed excitation frequencies could be described with a good accuracy taking
into account that the velocities and pressures of the contacting media on the
external and internal resonator surfaces are equal. The necessity of accounting
for oscillations with non--zero self--values of angular momentum operator has
been shown when describing the features of localization of several bubbles. To
explain a strangely small distance between the bubbles in the case of
two--bubble sonoluminescence the following possible explanations have been
proposed: a) mechanism of space splitting of a mode with a singular angular
momentum and b) mechanism of secondary excitation when one of the bubbles is
trapped into the acoustic trap created by high--frequency vibrations arising
simultaneously when the other bubble sonoluminescence occurs.


title: Spin and Statistics in Classical Mechanics

abstract:
  The spin-statistics conection is obtained for classical point particles. The
connection holds within pseudomechanics, a theory of particle motion that
extends classical physics to include anticommuting Grassmann variables, and
which exhibits classical analogs of both spin and statistics. Classical
realizations of Lie groups can be constructed in a canonical formalism
generalized to include Grassmann variables. The theory of irreducible canonical
realizations of the Poincare group is developed in this framework, with
particular emphasis on the rotation subgroup. The behavior of irreducible
realizations under time inversion and charge conjugation is obtained. The
requirement that the Lagrangian retain its form under the cominbed operation CT
leads directly to the spin-statistics connection, by an adaptation of
Schwinger's 1951 proof to irreducible canonical realizations of the Poincare
group of spin j: Generalized spin coordinates and momenta satisfy fundamental
Poisson bracket relations for 2j=even, and fundamental Poisson antibracket
relations for 2j=odd.


title: Ultrafast Dynamics for Electron Photodetachment from Aqueous Hydroxide

abstract:
  Charge-transfer-to-solvent (CTTS) reactions of hydroxide induced by 200 nm
monophotonic or 337 nm and 389 nm biphotonic excitation of this anion in
aqueous solution have been studied by means of pump-probe ultrafast laser
spectroscopy. Transient absorption kinetics of the hydrated electron, eaq-,
have been observed, from a few hundred femtoseconds out to 600 ps, and studied
as function of hydroxide concentration and temperature. The geminate decay
kinetics are bimodal, with a fast exponential component (ca. 13 ps) and a
slower power "tail" due to the diffusional escape of the electrons. For the
biphotonic excitation, the extrapolated fraction of escaped electrons is 1.8
times higher than for the monophotonic 200 nm excitation (31% vs. 17.5% at 25
oC, respectively), due to the broadening of the electron distribution. The
biphotonic electron detachment is very inefficient; the corresponding
absorption coefficient at 400 nm is < 4 cm TW-1 M-1 (assuming unity quantum
efficiency for the photodetachment). For [OH-] between 10 mM and 10 M, almost
no concentration dependence of the time profiles of solvated electron kinetics
was observed. At higher temperature, the escape fraction of the electrons
increases with a slope of 3x10-3 K-1 and the recombination and
diffusion-controlled dissociation of the close pairs become faster. Activation
energies of 8.3 and 22.3 kJ/mol for these two processes were obtained. The
semianalytical theory of Shushin for diffusion controlled reactions in the
central force field was used to model the geminate dynamics. The implications
of these results for photoionization of water are discussed.


title: Liquid Xe scintillation calorimetry and Xe optical properties

abstract:
  The optical properties of LXe in the vacuum ultra violet (VUV), determining
the performance of a scintillation calorimeter, are discussed in detail. The
available data, measured in a wider spectral region from visible to UV light,
and in a large range of Xe densities, from gas to liquid, are examined. It is
shown that this information can be used for deriving the LXe optical properties
in the VUV. A comparison is made with the few direct measurements in LXe for
VUV light resulting from the LXe excitation by ionizing particles. A useful
relation is obtained which connects the Rayleigh scattering length to the
refractive index in LXe.


title:
Chain-induced effects in the Faraday instability on ferrofluids in a
  horizontal magnetic field

abstract:
  The linear stability analysis of the Faraday instability on a viscous
ferrofluid in a horizontal magnetic field is performed. Strong dipole-dipole
interactions lead to the formation of chains elongated in the field direction.
The formation of chains results in a qualitative new behaviour of the
ferrofluid. This new behaviour is characterized by a neutral stability curve
similar to that observed earlier for Maxwell viscoelastic liquids and causes a
significant weakening of the energy dissipation at high frequencies. In the
case of a ferrofluid with chains in a horizontal magnetic field, the effective
viscosity is anisotropic and depends on the field strength as well as on the
wave frequency.


title:
Light-Pressure-Induced Shifts of 2^3S(J=1) = 2^3P(J=0,1,2) Helium Lines
  in a Vapor Cell and Implications for the Fine Structure Constant Measurement

abstract:
  This paper has been temporarily withdrawn by the authors. In the process of
4He 2P fine structure measurement in a vapor cell, highly nonlinear dependences
of 2S_1 - 2P_J intervals on helium density are observed and attributed to light
pressure. If total angular momentum of the excited state is not greater than
that of the ground state, there are large polarization dependences and
variations of shifts with helium pressure that exhibit apparent singularities.
A pressure-variable cell may be a better system for control of this effect than
an atomic beam. A method of avoiding the shifts for the fine structure
measurement is suggested.


title:
Nonlinear Variation of Light-Pressure-Induced Multilevel Atomic Line
  Shifts with Vapor Pressure in Helium Spectroscopy

abstract:
  This paper has been temporarily withdrawn. Highly nonlinear dependences of
4He 2^3S - 2^3P lines on pressure were observed in vapor cell saturation
spectroscopy. Line shifts agree with those expected from light-pressure-induced
perturbation of atomic velocity distribution. In the lin-perp-lin pump and
probe polarization configuration, multilevel atomic structure must be taken
into account. For a two-level atom, the shift magnitude is determined by the
collisional time constant, but when the system has dark states there is an
additional time constant due to optical pumping. The collisional and optical
time constants compete, and become equal at a certain pressure p_0. Saturation
signal vanishes at p_0 whereas signal due to light pressure remains. This leads
to a dependence of line centers on pressure that exhibits apparently singular
behavior at p_0. The 2S - 2P(J=1) line shift reaches the natural half width.
Vapor cells may be more suitable for investigation of this effect than atomic
beams since the shifts vanish at sufficiently high pressures. Two ways of
controlling the shifts for the helium 2P fine structure measurement are
discussed.


title: Air-core photonic band-gap fibers: the impact of surface modes

abstract:
  We study the dispersion and leakage properties for the recently reported
low-loss photonic band-gap fiber by Smith et al. [Nature 424, 657 (2003)]. We
find that surface modes have a significant impact on both the dispersion and
leakage properties of the fundamental mode. Our dispersion results are in
qualitative agreement with the dispersion profile reported recently by Ouzounov
et al. [Science 301, 1702 (2003)] though our results suggest that the observed
long-wavelength anomalous dispersion is due to an avoided crossing (with
surface modes) rather than band-bending caused by the photonic band-gap
boundary of the cladding.


title: Is Computation Reversible?

abstract:
  Recent investigations into the physical nature of information and fundamental
limits to information transmission have revealed questions such as the
possibility of superluminal data transfer or not; and whether reversible
computation (information processing) is feasible. In some respects these
uncertainties stem from the determination of whether information is inherent in
points of non-analyticity (discontinuities) or smoother functions. The close
relationship between information and entropy is also well known, e.g.
Brillouin's concept of negentropy (negative entropy) as a measure for
information. Since the leading edge of a step-discontinuity propagates in any
dispersive medium at the speed of light in vacuum as a precursor to the main
body of the dispersed pulse, we propose in this paper to treat information as
being intrinsic to points of non-analyticity (discontinuities). This allows us
to construct a theory addressing these dilemmas in a fashion consistent with
causality, and the fundamental laws of thermodynamics. A consequence of our
proposition is that the movement of information is always associated with the
dissipation of heat, and therefore that the concept of reversible classical
computation is not tenable.


title:
Linear waves and baroclinic instability in an inhomogeneous-density
  layered primitive-equation ocean model

abstract:
  We consider a multilayer generalization of Ripa's inhomogeneous-density
single-layer primitive-equation model. In addition to vary arbitrarily in
horizontal position and time, the horizontal velocity and buoyancy fields are
allowed to vary linearly with depth within each layer of the model. Preliminary
results on linear waves and baroclinic instability suggest that a configuration
involving a few layers may set the basis for a quite accurate and numerically
efficient ocean model.


title:
Optimizing the vertebrate vestibular semicircular canal: could we
  balance any better?

abstract:
  The fluid-filled semicircular canals (SCCs) of the vestibular system are used
by all vertebrates to sense angular rotation. Despite masses spanning seven
decades, all mammalian SCCs are nearly the same size. We propose that the SCC
represents a sensory organ that evolution has `optimally designed'. Four
geometric parameters are used to characterize the SCC, and `building materials'
of given physical properties are assumed. Identifying physical and
physiological constraints on SCC operation, we find that the most sensitive SCC
has dimensions consistent with available data.


title:
Electron Photodetachment from Aqueous Anions. I. Quantum Yields for
  Generation of Hydrated Electron by 193 and 248 nm Laser Photoexcitation of
  Miscellaneous Inorganic Anions

abstract:
  Time resolved transient absorption spectroscopy has been used to determine
quantum yields for electron photodetachment in 193 nm and (where possible) 248
nm laser excitation of miscellaneous aqueous anions, including
hexacyanoferrate(II), sulfate, sulfite, halide anions (Cl-, Br-, and I-),
pseudohalide anions (OH-, HS-, CNS-), and several common inorganic anions for
which no quantum yields have been reported heretofore: SO3=, NO2-, NO3-, ClO3-
and ClO4-. Molar extinction coefficients for these anions and photoproducts of
electron detachment from these anions at the excitation wavelengths were also
determined. These results are discussed in the context of recent ultrafast
kinetic studies and compared with the previous data obtained by product
analyses. We suggest using electron photodetachment from the aqueous halide and
pseudohalide anions as actinometric standard for time-resolved studies of
aqueous photosystems in the UV.


title: Non-Hermitian Rayleigh-Schroedinger Perturbation Theory

abstract:
  We devise a non-Hermitian Rayleigh-Schroedinger perturbation theory for the
single- and the multireference case to tackle both the many-body problem and
the decay problem encountered, for example, in the study of electronic
resonances in molecules. A complex absorbing potential (CAP) is employed to
facilitate a treatment of resonance states that is similar to the
well-established bound-state techniques. For the perturbative approach, the
full CAP-Schroedinger Hamiltonian, in suitable representation, is partitioned
according to the Epstein-Nesbet scheme. The equations we derive in the
framework of the single-reference perturbation theory turn out to be identical
to those obtained by a time-dependent treatment in Wigner-Weisskopf theory. The
multireference perturbation theory is studied for a model problem and is shown
to be an efficient and accurate method. Algorithmic aspects of the integration
of the perturbation theories into existing ab initio programs are discussed,
and the simplicity of their implementation is elucidated.


title:
On the Well-Mixed Quasi-One-Dimensional Formulation of Lagrangian
  Stochastic Models for Turbulent Relative Dispersion

abstract:
  This paper has been withdrawn by the author due to a crucial error in the
formulation.


title:
Electric/magnetic reciprocity in premetric electrodynamics with and
  without magnetic charge, and the complex electromagnetic field

abstract:
  We extend an axiomatic approach to classical electrodynamics, which we
developed recently, to the case of non-vanishing magnetic charge. Then two
axioms, namely those of the existence of the Lorentz force (Axiom 2) and of
magnetic flux conservation (Axiom 3) have to be generalized. Electric/magnetic
reciprocity constitutes a guiding principle for this undertaking. The extension
of the axioms can be implemented at a premetric stage, i.e., when metric and
connection of spacetime don't play a role. Complex Riemann-Silberstein fields
of the form $(E\pm i {\cal H},{\cal D}\pm i B)$ have a natural place in the
theory, independent of the Hodge duality mapping defined by any particular
metric.


title:
Laser Generated Magnetic Pulses: Hot Electron Propagation in Conducting
  and Dielectric Material

abstract:
  We report experimental evidence of electrostatic inhibition of fast
electrons, generated in a highly resistive material upon irradiation with an
intense ultra-short ($10^{16} W/cm^{2}$, $100 fmsec$) laser pulse. The
experiment involves measurement of temporal evolution of self-generated
magnetic pulses using pump-probe polarimetry. A comparison is made between the
temporal behaviour of magnetic pulses generated with Aluminum and Glass
targets. It is found that in contrast to Aluminium, self-generated magnetic
pulse decays much faster in glass. This is attributed to the absence of return
shielding currents in glass, which results in build up of electrostatic field,
which in turn inhibits the movement of fast electrons. Fitting of experimental
measurements using a one dimensional model, yields estimate of conductivity of
Aluminium and glass, and penetration depth of hot electrons in these materials.


title: High Level Trigger Using ALICE ITS Detector

abstract:
  The high $P_T$ trigger capabilities of the ALICE inner tracking system (ITS)
as a standalone detector have been investigated. Since the high $P_T$ charged
particles mostly lead to the linear trajectories within this ITS sector, it is
possible to select tracks of $P_T$ of the order of 2 GeV and above by confining
to a narrow search window in the ($\theta,\phi$) space. Also shown that by
performing a principal component transformation, it is possible to rotate from
a 12 dimensional ($\theta$-$\phi$) space (in this space, a good ITS track has 6
pairs of hit co-ordinates) into a parametric space characterized by only two
independent components when the track momentum exceeds a particular limit. This
independent component analysis (ICA) has been uitilised further to reduce the
false track contribution to an acceptable level particularly when the charged
multiplicity is large. Finally, it is shown that with a narrow bin width of
$\Delta \theta = \Delta \phi \sim 0.008$ radian and with PCA or ICA cut, the
ITS can be used to trigger the jet particles with $P_T \ge 2 $ GeV. Apart from
triggering these high $P_T$ particles, this method can also be used to estimate
the initial momentum of the high $P_T$ tracks for seeding which can be further
prolonged into the TPC detector both for offline and online Kalman tracking or
even to detect those high $P_T$ tracks of rare events which might get lost in
the TPC-TRD dead zone.


title: A novel formulation of nonlocal electrostatics

abstract:
  The accurate modeling of the dielectric properties of water is crucial for
many applications in physics, computational chemistry and molecular biology.
This becomes possible in the framework of nonlocal electrostatics, for which we
propose a novel formulation allowing for numerical solutions for the nontrivial
molecular geometries arising in the applications mentioned before. Our approach
is based on the introduction of a secondary field, $\psi$, which acts as the
potential for the rotation free part of the dielectric displacement field ${\bf
D}$. For many relevant models, the dielectric function of the medium can be
expressed as the Green's function of a local differential operator. In this
case, the resulting coupled Poisson (-Boltzmann) equations for $\psi$ and the
electrostatic potential $\phi$ reduce to a system of coupled PDEs. The approach
is illustrated by its application to simple geometries.


title: Results from the Alghero Workshop on e+e- in the 1-2 GeV range

abstract:
  In the post-LEP era the high energy frontier is reachable only by large scale
collaborations and laboratories, while the present lepton colliders operating
at low and intermediate energies are planning major upgrades aimed at
increasing substantially their luminosity, in order to meet the continuous
interest in precision physics. The lowest energies are now represented by
DAPHNE (1.02 GeV cm, operating at Frascati), VEPP-2000 (from 1 to 2 GeV, in
construction at Novosibirsk), CESR (presently operating at Cornell in the range
between 3 to 12 GeV), BEPC (presently operating in Beijing in the range 2 to
5.6 GeV, foreseen luminosity upgrade). A workshop has been held to discuss both
the physics issues and the strategies and problems towards higher luminosities
in the energy range mainly but not only between 1 and 2 GeV. The workshop was
intended to clarify which experiments are more appealing to the physics
community, and which is the way to proceed for obtaining the necessary
luminosity.


title:
Scattering of low- to intermediate-energy positrons from molecular
  hydrogen

abstract:
  Using a complex model potential, we have calculated the total, integrated
elastic, momentum transfer, absorption, and differential cross sections for
positrons scattered from molecular hydrogen. The widely available software
package GAUSSIAN is used to generate the radial electronic charge density of
the molecule which is used to produce the interaction potentials. The quasifree
absorption potential, previously developed and used for positron-atom
scattering, is extended to positron scattering from molecular targets. It is
shown that this model potential approach produces accurate results even into
the low-energy regime.


title: Switching of Discrete Solitons in Engineered Waveguide Arrays

abstract:
  We demonstrate a simple method for controlling nonlinear switching of
discrete solitons in arrays of weakly coupled optical waveguides, for both
cubic and uadratic nonlinearities. Based on the effective discrete nonlinear
equations describing the waveguide arrays in the tight-binding approximation,
we develop the concept of the array engineering by means of a step-like
variation of the waveguide coupling. We demonstrate the digitized switching of
a narrow input beam for up to eleven neighboring waveguides, in the case of the
cubic nonlinearity, and up to ten waveguides, in the case of quadratic
nonlinearity. We discuss our predictions in terms of the physics of the
engineered Peierls-Nabarro (PN) potential experienced by strongly localized
nonlinear modes moving in a lattice and calculate, for the first time, the PN
potential for the quadratic nonlinear array. We also confirm our concept and
major findings for a full-scaled continuous model and realistic parameters, by
means of the beam propagation method.


title:
A dual set-up based on Bradley's aberration of light, using
  simultaneously stellar and local light sources

abstract:
  A dual optical set-up is proposed to detect simultaneously the different
behavior of light from stellar and local sources, in relation to speed-induced
aberration. A small laser is set at the center of the objective lens of a
telescope, allowing to record at once the two spots on an array detector. Their
positions are recorded during a yearly earth orbit, so stellar aberration can
be visualized as a tiny circle. But no aberration has been observed from local
sources, hence the laser spot should remain still. The simultaneous recording
of both spots allows highlighting their different behavior. Einstein related
aberration to the transverse speed between light source and observer, and since
for local sources it is null, no aberration ensues. Despite this explanation
conforms with the correct result for local sources, it cannot however be
retained since stellar aberration does not vary although relative speed differs
for each star. Consequently, the null transverse velocity cannot be considered
the cause of the null aberration from local sources. A causal approach to this
different behavior between stellar and local light is advanced, based on the
combined effects of a speed-induced deflection of emitted light rays and a
speed-induced aberration upon detection.


title:
A causal approach to first-order optical equivalency of inertial
  systems, by means of a beam-pointing test-experiment based on speed-induced
  deflection of light

abstract:
  Within the framework of test-experiments, an original pointing set-up based
on speed-induced deflection of a light-beam and using a high-resolution
opto-electronic array as a position detector, is proposed. The device would
provide a new way to ratify the first order optical equivalency of inertial
systems and to sound its causal groundwork. The type of test provided applies
to any device using beams, but here it has been adapted for an up-dated
check-up of Michelson's experiment and to bear out the interpretation derived
from its null result. Rather than searching for a speed-induced phase-shift as
Michelson's experiment was conceived for, the present set-up would instead
detect any deviation from first-order equivalency through any speed-induced
lateral-shift between the two split beams on recombining. In effect, any
eventual slight shift would affect the beam path and hence the interferometric
performances. Taking into account the conceptual transcendence of the
deductions derived from this experiment and that it constitutes, through the
invariance of its result, one of the most relevant historical experimental
proofs considered to back the theory of special relativity, and in particular
its first postulate on the exhaustive equivalency of inertial systems, it
cannot be superfluous to carefully update its performances and the derived
deductions. So, the presence as well as the absence of speed-induced beam
deflection have been considered, and their respective implications analyzed and
related to the null result of this archetypal interferometric experiment, which
is still much adequate for a conceptual analysis. A causal approach to the
first-order optical equivalency of inertial systems is advanced.


title:
First and second order electromagnetic equivalency of inertial systems,
  based on the wavelength and the period as speed-dependant units of length and
  time

abstract:
  The cause for first and second order electromagnetic equivalency of inertial
systems is approached from a different point of view than that of special
relativity. While special relativity applies dilatation to time and contraction
to space itself, the proposed framework applies restrictively these effects to
the units of space and time, embodied in the beam wavelength and period, as
perceived on the inertial system due to the Doppler effect. It is not space and
time themselves that would actually vary but the electromagnetic units of space
and time constituted by the wavelength and period. Mathematical constructs
accept indifferently both setting out, which provide identical results, so
their valuation must be made on physical grounds. The reader is invited to
ponder on interpreting physical reality through the contraction of space and
dilatation of time or through the variation of the natural units of space and
time provided by the wavelength and the period. These two issues,
mathematically equivalent, lead however to drastically different conceptions of
the physical world.


title: Hybrid molecular-continuum fluid dynamics

abstract:
  We describe recent developments in the hybrid atomistic/continuum modelling
of dense fluids. We discuss the general implementation of mass, momentum and
energy transfers between a region described by molecular dynamics and the
neighbouring domain described by the Navier-Stokes equations for unsteady flow.
The effect of fluctuations from the particle system in the scheme accuracy is
also studied.


title: Tunable transmission and bistability in left-handed bandgap structures

abstract:
  We study the defect-induced nonlinear transmission of a periodic structure
created by alternating slabs of two materials with positive and negative
refractive index. We demonstrate bistable switching and tunable nonlinear
transmission in a novel type of bandgap that corresponds to the vanishing
average refractive index, and compare the observed effects for two types of the
bandgaps.


title: Systematic study of the decay rates of antiprotonic helium states

abstract:
  A systematic study of the decay rates of antiprotonic helium (\pbhef and
\pbhet) at CERN AD (Antiproton Decelerator) has been made by a laser
spectroscopic method. The decay rates of some of its short-lived states, namely
those for which the Auger rates $\gamma_{\mathrm{A}}$ are much larger than
their radiative decay rates ($\gamma_{\mathrm{rad}} \sim 1$ $\mu$s$^{-1}$),
were determined from the time distributions of the antiproton annihilation
signals induced by laser beams, and the widths of the atomic resonance lines.
The magnitude of the decay rates, especially their relation with the transition
multipolarity, is discussed and compared with theoretical calculations.


title: Sodium atoms and clusters on graphite: a density functional study

abstract:
  Sodium atoms and clusters (N<5) on graphite (0001) are studied using density
functional theory, pseudopotentials and periodic boundary conditions. A single
Na atom is observed to bind at a hollow site 2.45 A above the surface with an
adsorption energy of 0.51 eV. The small diffusion barrier of 0.06 eV indicates
a flat potential energy surface. Increased Na coverage results in a weak
adsorbate-substrate interaction, which is evident in the larger separation from
the surface in the cases of Na_3, Na_4, Na_5, and the (2x2) Na overlayer. The
binding is weak for Na_2, which has a full valence electron shell. The presence
of substrate modifies the structures of Na_3, Na_4, and Na_5 significantly, and
both Na_4 and Na_5 are distorted from planarity. The calculated formation
energies suggest that clustering of atoms is energetically favorable, and that
the open shell clusters (e.g. Na_3 and Na_5) can be more abundant on graphite
than in the gas phase. Analysis of the lateral charge density distributions of
Na and Na_3 shows a charge transfer of about 0.5 electrons in both cases.


title:
2D ground motion at a soft viscoelastic layer/hard substratum site in
  response to SH cylindrical seismic waves radiated by deep and shallow line
  sources

abstract:
  We show, essentially by theoretical means, that for a site with the chosen
simple geometry and mechanical properties (horizontal, homogeneous, soft
viscoelastic layer of infinite lateral extent overlying, and in welded contact
with, a homogeneous, hard elastic substratum of half-infinite radial extent,
shear-horizontal motion): 1) coupling to Love modes is all the weaker the
farther the seismic source (modeled as a line, assumed to lie in the
substratum) is from the lower boundary of the soft layer, 2) for a line source
close to the lower boundary of the soft layer, the ground response is
characterized by possible beating phenomena, and is of significantly-longer
duration than for excitation by cylindrical waves radiated by deep sources.
Numerical applications of the theory show, for instance, that a line source,
located 40m below the lower boundary of a 60m thick soft layer in a
hypothetical Mexico City-like site, radiating a SH pulse of 4s duration,
produces substantial ground motion during 200s, with marked beating, at an
epicentral distance of 3km. This response is in some respects similar to that
observed in real cities located at soft-soil sites so that the model employed
herein may help to establish the causes and pinpoint the major contributing
factors of the devastating effects of earthquakes in such cities.


title: Could the classical relativistic electron be a strange attractor?

abstract:
  We review the formulation of the problem of the electromagnetic
self-interaction of a relativistic charged particle in the framework of the
manifestly covariant classical mechanics of Stueckelberg, Horwitz and Piron.
The gauge fields of this theory, in general, cause the mass of the particle to
change. We show that the non-linear Lorentz force equation for the
self-interaction resulting from the expansion of the Green's function has
chaotic solutions. We study the autonomous equation for the off-shell particle
mass here, for which the effective charged particle mass achieves a macroscopic
average value determined by what appears to be a strange attractor.

categories: physics.class-ph math-ph math.MP nlin.CD


title: Diffusion in a slab: different approaches

abstract:
  Different approaches are presented to investigate diffusion from a point
source in a slab delimited by two absorbing boundaries consisting of parallel
infinite planes. These approaches enable to consider the effect of absorption
at the boundaries as well as the possibility that the particles that diffuse
react with the diffusive medium.


title: The prosody and the music of the human speech

abstract:
  We propose the use of a self-oscillating dynamical system --the pre-Galileian
clock equation-- for modeling the laryngeal tone. The parameters are shown to
be the minimal control needed for generating the prosody of the human speech.
Based on this model, we outline a peak delay detection algorithm for extracting
the prosody of the real speech.


title:
GPM Ground Validation Basic Radar Products and Implications for
  Observation Strategies

abstract:
  Recommendations are made for NASA/JAXA Global Precipitation Measurement (GPM)
satellite Ground Validation (GV) program. This report details recommended GV
site local radar products based on data from surface-based scanning radars
including S-band, C-band, and X-band polarimetric and non-polarimetric radars.
Three general categories of products are described: text products summarizing
information on the statistical characteristics of the radar data and derived
parameters, 2D products providing maps of the horizontal variability of near
surface radar observed and derived parameters, and 3D products describing
volumetric echo structure. Regional composites could include products based on
several of the 2D and 3D single radar products. Several types of
time-integrated 2D and 3D products are also recommended. A brief discussion of
useful ancillary data from other sources and remaining challenges concludes the
report.


title: Diffusion-based method for producing density equalizing maps

abstract:
  Map makers have long searched for a way to construct cartograms -- maps in
which the sizes of geographic regions such as countries or provinces appear in
proportion to their population or some other analogous property. Such maps are
invaluable for the representation of census results, election returns, disease
incidence, and many other kinds of human data. Unfortunately, in order to scale
regions and still have them fit together, one is normally forced to distort the
regions' shapes, potentially resulting in maps that are difficult to read. Many
methods for making cartograms have been proposed, some of them extremely
complex, but all suffer either from this lack of readability or from other
pathologies, like overlapping regions or strong dependence on the choice of
coordinate axes. Here we present a new technique based on ideas borrowed from
elementary physics that suffers none of these drawbacks. Our method is
conceptually simple and produces useful, elegant, and easily readable maps. We
illustrate the method with applications to the results of the 2000 US
presidential election, lung cancer cases in the State of New York, and the
geographical distribution of stories appearing in the news.


title:
Spectroscopic study of unique line broadening and inversion in
  low-pressure microwave generated water plasmas

abstract:
  It was demonstrated that low pressure (~0.2 Torr) water vapor plasmas
generated in a 10 mm inner diameter quartz tube with an Evenson microwave
cavity show at least two features which are not explained by conventional
plasma models. First, significant (> 0.25 nm) hydrogen Balmer_ line broadening,
of constant width, up to 5 cm from the microwave coupler was recorded. Only
hydrogen, and not oxygen, showed significant line broadening. This feature,
observed previously in hydrogen-containing mixed gas plasmas generated with
high voltage dc and rf discharges was explained by some researchers to result
from acceleration of hydrogen ions near the cathode. This explanation cannot
apply to the line broadening observed in the (electrodeless) microwave plasmas
generated in this work, particularly at distances as great as 5 cm from the
microwave coupler. Second, inversion of the line intensities of both the Lyman
and Balmer series, again, at distances up to 5 cm from the coupler, were
observed. The line inversion suggests the existence of a hitherto unknown
source of pumping of the optical power in plasmas. Finally, it is notable that
other aspects of the plasma including the OH* rotational temperature and low
electron concentrations are quite typical of plasmas of this type.


title: The Enhancement of Confocal Images of Tissues at Bulk Optical Immersion

abstract:
  The purpose of the present work is a theoretical examination of how localized
skin-tissue dehydration affects the depth of the confocal probing and what
depth of effective detection can be reached with the chemical administration of
skin tissues. A semi-infinite multilayer Monte Carlo model is used to estimate
spatial localization of the output signal offered by a confocal probe. A
solution of glycerol is taken in the capacity of innocuous osmotic agent.
Diffusion of this bio-compatible chemical agent into the skin temporarily
pushes water out of the tissues and results in the matching of the refractive
indices of skin structural elements. This temporarily decreases scattering and
increases transparency of topical skin layers, which allows for unrestricted
light to permeate deeper into the skin. The results of simulation show that
signal spatial localization offered by a confocal probe in the skin tissues
during their clearing is usable for the monitoring of deep reticular dermis and
improving the image contrast and spatial resolution. A discussion of the
optical properties of skin tissues and their changes due to diffusion of
glycerol into the skin is given. Optical properties of tissues and their
changes due to chemical administration are estimated based on the results of
experimental in vitro study with rat and human skin.


title: Polarization Measurements - A Numerical Approach

abstract:
  We developed a specific numerical fitting procedure, based on the least
squares method, to calculate the parameters of the polarization ellipse by only
using a single polarizer and a detection device for measuring the outgoing
intensities.


title: Front-End electronics and integration of ATLAS pixel modules

abstract:
  For the ATLAS Pixel Detector fast readout electronics has been successfully
developed and tested. Main attention was given to the ability to detect small
charges in the order of 5,000 electrons within 25 ns in the harsh radiation
environment of LHC together with the challenge to cope with the huge amount of
data generated by the 80 millions channels of the Pixel detector. For the
integration of the 50 micron pitch hybrid pixel detector reliable bump bonding
techniques using either lead-tin or indium bumps has been developed and has
been successfully tested for large scale production.


title:
Calculation of electron density of periodic systems using non-orthogonal
  localised orbitals

abstract:
  Methods for calculating an electron density of a periodic crystal constructed
using non-orthogonal localised orbitals are discussed. We demonstrate that an
existing method based on the matrix expansion of the inverse of the overlap
matrix into a power series can only be used when the orbitals are highly
localised (e.g. ionic systems). In other cases including covalent crystals or
those with an intermediate type of chemical bonding this method may be either
numerically inefficient or fail altogether. Instead, we suggest an exact and
numerically efficient method which can be used for orbitals of practically
arbitrary localisation. Theory is illustrated by numerical calculations on a
model system.


title:
Comparison of localization procedures for applications in crystal
  embedding

abstract:
  With the aim of future applications in quantum mechanical embedding in
extended systems such as crystals, we suggest a simple and computationally
efficient method which enables construction of a set of nonorthogonal highly
localized one-electron orbitals for periodic nonmetallic crystals which reflect
their chemical nature. The orbitals are also used to build up the Hartree-Fock
(HF) electron density of the entire crystals. The simplicity of the method
stems from the fact that it does not require usage and/or modification of
periodic electronic structure codes, and is instead based on the HF calculation
of a sequence of finite clusters with subsequent application of a localization
procedure to transform the HF canonical molecular orbitals. Two extreme cases
of chemical bonding, ionic (MgO crystal) and covalent (Si crystal), are
considered for which a number of known localization schemes are applied and
compared. With some modifications our method can also be applied to nonperiodic
nonmetallic systems as well.


title:
Analysis of skin tissues spatial fluorescence distribution by the Monte
  Carlo simulation

abstract:
  A novel Monte Carlo technique of simulation of spatial fluorescence
distribution within the human skin is presented. The computational model of
skin takes into account the spatial distribution of fluorophores, which would
arise due to the structure of collagen fibres, compared to the epidermis and
stratum corneum where the distribution of fluorophores is assumed to be
homogeneous. The results of simulation suggest that distribution of auto-
fluorescence is significantly suppressed in the near-infrared spectral region,
whereas the spatial distribution of fluorescence sources within a sensor layer
embedded in the epidermis is localized at an effective depth.


title:
ITER: The International Thermonuclear Experimental Reactor and the
  nuclear weapons proliferation implications of thermonuclear-fusion energy
  systems

abstract:
  This report contains two parts: (1) A list of "points" highlighting the
strategic-political and military-technical reasons and implications of the very
probable siting of ITER (the International Thermonuclear Experimental Reactor)
in Japan, which should be confirmed sometimes in early 2004. (2) A technical
analysis of the nuclear weapons proliferation implications of inertial- and
magnetic-confinement fusion systems substantiating the technical points
highlighted in the first part, and showing that while full access to the
physics of thermonuclear weapons is the main implication of ICF, full access to
large-scale tritium technology is the main proliferation impact of MCF. The
conclusion of the report is that siting ITER in a country such as Japan, which
already has a large separated-plutonium stockpile, and an ambitious
laser-driven ICF program (comparable in size and quality to those of the United
States or France), will considerably increase its latent (or virtual) nuclear
weapons proliferation status, and foster further nuclear proliferation
throughout the world.


title:
Recent Progress at SLAC Extracting High Charge from Highly-Polarized
  Photocathodes for Future-Collider Applications

abstract:
  Future colliders such as NLC and JLC will require a highly-polarized
macropulse with charge that is more than an order of magnitude beyond that
which could be produced for the SLC. The maximum charge from the SLC
uniformly-doped GaAs photocathode was limited by the surface charge limit
(SCL). The SCL effect can be overcome by using an extremely high (>1019 cm-3)
surface dopant concentration. When combined with a medium dopant concentration
in the majority of the active layer (to avoid depolarization), the surface
concentration has been found to degrade during normal heat cleaning (1 hour at
600 C). The Be dopant as typically used in an MBE-grown superlattice cathode is
especially susceptible to this effect compared to Zn or C dopant. Some relief
can be found by lowering the cleaning temperature, but the long-term general
solution appears to be atomic hydrogen cleaning.


title: On the Persistence of Particles

abstract:
  This paper is about the metaphysical debate whether objects persist over time
by the selfsame object existing at different times (nowadays called `endurance'
by metaphysicians), or by different temporal parts, or stages, existing at
different times (called ` perdurance'). I aim to illuminate the debate by using
some elementary kinematics and real analysis: resources which metaphysicians
have, surprisingly, not availed themselves of. There are two main results,
which are of interest to both endurantists and perdurantists.
  (1): I describe a precise formal equivalence between the way that the two
metaphysical positions represent the motion of the objects of classical
mechanics (both point-particles and continua).
  (2): I make precise, and prove a result about, the idea that the persistence
of objects moving in a void is to be analysed in terms of tracking the
continuous curves in spacetime that connect points occupied by matter. The
result is entirely elementary: it is a corollary of the Heine-Borel theorem.


title: Accurate S-state helium wave functions in momentum space

abstract:
  High accuracy helium wave functions based on exponentials with random
coefficients are transformed into momentum space. The utility of the wave
functions is demonstrated through calculation of the expectation value of
various operators needed to evaluate relativistic and QED corrections.


title: Quantum probe for molecular synthesis at room temperature

abstract:
  In the present study, a prototypical reaction in biochemistry involving a
well-known bio-molecule called imidazole (C3H4N2) and its known affinity
towards transition metals (such as Co, Ni, Cu, Fe, etc.) has been used to
illustrate and exemplify the use of ballistic conductors as probes for
molecular reactions at the quantum level. Atomic point contacts of transition
metal Co were made using electro-deposition, followed by their reaction with
imidazole in an aqueous solution. As the imidazole molecules covalently bond
with the Co atoms, the quantized conductance of the nanocontact decreases, thus
providing a quantum probe for studying molecular reactions. During the course
of the reaction, different conductance channels within the nanocontact become
unavailable due to covalent bonding of Co with imidazole, thereby also
providing a means of studying the number of channels contributing to the total
conductance in the nanocontact itself.


title:
Effects of the Charge-Dipole Interaction on the Coagulation of Fractal
  Aggregates

abstract:
  A numerical model with broad applications to complex (dusty) plasmas is
presented. The self-consistent N-body code allows simulation of the coagulation
of fractal aggregates, including the charge-dipole interaction of the clusters
due to the spatial arrangement of charge on the aggregate. It is shown that not
only does a population of oppositely charged particles increase the coagulation
rate, the inclusion of the charge-dipole interaction of the aggregates as well
as the electric dipole potential of the dust ensemble decreases the gelation
time by a factor of up to twenty. It is further shown that these interactions
can also stimulate the onset of gelation, or "runaway growth," even in a
population of particles charged to a monopotential where previously it was
believed that like-charged grains would inhibit coagulation. Gelation is
observed to occur due to the formation of high-mass aggregates with fractal
dimensions greater than two which act as seeds for runaway growth.


title: Tunable Resonant Optical MicroCavities by Self-Assembled Templating

abstract:
  Micron-scale optical cavities are produced using a combination of template
sphere self-assembly and electrochemical growth. Transmission measurements of
the tunable microcavities show sharp resonant modes with a Q-factor>300, and
25-fold local enhancement of light intensity. The presence of transverse
optical modes confirms the lateral confinement of photons. Calculations show
sub-micron mode volumes are feasible. The small mode volume of these
microcavities promises to lead to a wide range of applications in microlasers,
atom optics, quantum information, biophotonics and single molecule detection.


title: Atmospheric pressure loading for routine data analysis

abstract:
  We have computed 3-D displacements induced by atmospheric pressure loading
from 6-hourly surface pressure field from NCEP (National Center for
Environmental Predictions) Reanalysis data for all Very Long Baseline
Interferometry) and SLR (Satellite Laser Ranging) stations. We have
quantitatively estimated the error budget our time series of pressure loading
and found that the errors are below 15%. We validated our loading series by
comparing them with a dataset of 3.5 million VLBI observations for the period
of 1980--2003. We have shown that the amount of power which is present in the
loading time series, but does not present in the VLBI data is, on average, only
5%. We have also succeeded, for the first time, to detect horizontal
displacements caused by atmospheric loading. The correction of atmospheric
loading in VLBI data allows a significant reduction of baseline repeatability,
except for the annual component.


title: Using a Numerical Weather Model to Improve Geodesy

abstract:
  The use of a Numerical Weather Model (NWM) to provide in situ atmosphere
information for mapping functions of atmosphere delay has been evaluated using
Very Long Baseline Interferometry (VLBI) data spanning eleven years. Parameters
required by the IMF mapping functions (Niell 2000, 2001) have been calculated
from the NWM of the National Centers for Environmental Prediction (NCEP) and
incorporated in the CALC/SOLVE VLBI data analysis program. Compared with the
use of the NMF mapping functions (Niell 1996) the application of IMF for global
solutions demonstrates that the hydrostatic mapping function, IMFh, provides
both significant improvement in baseline length repeatability and noticeable
reduction in the amplitude of the residual harmonic site position variations at
semidiurnal to long-period bands. For baseline length repeatability the
reduction in the observed mean square deviations achieves 80 of the maximum
that is expected for the change from NMF to IMF. On the other hand, the use of
the wet mapping function, IMFw, as implemented using the NCEP data, results in
a slight degradation of baseline length repeatability, probably due to the
large grid spacing of the NWM that is used.


title:
On the sensitivity of coastal quasigeostrophic edge wave interaction to
  bottom boundary characteristics: possible implications for eddy
  parameterizations

abstract:
  The Eady problem of baroclinic instability as applicable to quasi-geostrophic
oceanic flows with zero internal PV gradients is revisited by introducing a
mild slope and Ekman pumping on the lower boundary. The solution behaviour is
determined by the isopycnal slope relative to either the bottom slope or the
ratio of Ekman depth to horizontal wavenumber. Attention is paid to the
physical interpretation of the growing, decaying and stable disturbances, with
emphasis on the intimate connection between the quasigeostrophic edge waves and
Eady waves, and the role of the isopycnal slope for the stability properties as
opposed to the bottom density gradient. The disturbance structure is found to
be strongly influenced by the boundary conditions.
  For a sloping bottom boundary, the growth rate is enhanced for the most
unstable waves if the isopycnals tilt in the same direction as the bottom, but
in general non-standard boundary conditions tend to retard the growth of
disturbances. In particular, the existence of the long- and short-wave cutoffs
is found to be very sensitive to boundary conditions, both for the sloping
topography and the Ekman pumping. It is suggested that any cutoffs for the
growth rate in an Eady-like problem actually result from the chosen boundary
conditions. However, for a certain range of parameters, the maximum growth rate
is comparable to that found in the original Eady problem, which may explain the
fair success enjoyed by recent eddy parameterizations basing their timescale on
the Eady growth rate.


title: Ionization of hydrogen and ionized helium by slow antiprotons

abstract:
  We study the ionization process involving antiproton and hydrogen in the
energy range between 0.1 keV to 500 keV, using single center close coupling
approximation. We construct the scattering wave function using B-spline bases.
The results obtained for ionization of atomic hydrogen are compared with other
existing theoretical calculations as well as with the available experimental
data. The present results are found to be encouraging. We also employed this
method to study the ionization of ionized helium in the energy range between 1
and 500 keV. On comparision, the present results are found to interpret well
the cross section values calculated using other theories.


title:
Measurement of the radiation field surrounding the Collider Detector at
  Fermilab

abstract:
  We present here the first direct and detailed measurements of the spatial
distribution of the ionizing radiation surrounding a hadron collider
experiment. Using data from two different exposures we measure the effect of
additional shielding on the radiation field around the Collider Detector at
Fermilab (CDF). Employing a simple model we parameterize the ionizing radiation
field surrounding the detector.


title: Folded Pendulum Measurements of Earth's Free Oscillations

abstract:
  The nearly-incessant free oscillations of the Earth (not the larger,
long-lived normal modes seen following intense quakes) were first observed by
accident in the record of a tilt-sensitive instrument designed to study surface
physics. Later tiltmeter studies demonstrated the usefulness of autocorrelation
for the routine study of these normally short-lived eigenmodes. More recent
studies suggest that many tilt-sensitive instruments are capable of observing
these oscillations--if the low-frequency response of their electronics is not
suppressed, as is customary with conventional designs.