title:
On the Formulation of Lagrangian Stochastic Models for Geophysical
  Turbulent Flows

abstract:
  This paper has been withdrawn by the author(s), due to a crucial error in eq.
6.


title:
Difficulties of Model Construction in Optics (Probleme der Modellbildung
  in der Optik)

abstract:
  Throughout all years of study, students of physics are confronted with the
question 'what exactly is light?' - a question that is impossible to answer
correctly and, therefore, continuously discussed within the framework of
models. Numerous models have been introduced for this purpose and subsequently
compete with one another for validity. On the one hand, this may lead to
learning difficulties. Yet, on the other hand, this may be considered a
didactic chance, if thinking about the model is compounded with the
consideration of models in general. Research in secondary school level II
physics classes and with physics students provides insight into the processes
of model construction as well as that of overcoming models, which will be
presented and analyzed here. The possibilities which computer simulations
provide for the discussion of various models of light are demonstrated and
their influence on a structured construction of models will be discussed.


title: Feasibility of the DAFNE-Linac energy doubling

abstract:
  The energy doubling of the Frascati DAFNE Phi-factory can be accomplished
either by ramping the energy of the rings from the initial 510 MeV of the
injected beam or by upgrading the present Linac Energy to > 1.02 GeV so to
inject the beam at full energy. The choice between the two options is not the
goal of this paper, that instead, presents some technical solutions, allowing
to re-use all the components of the DAFNE electron-positron Linac.


title: Generalized Paraxial Ray Trace Procedure Derived from Geodesic Deviation

abstract:
  Paraxial ray tracing procedures have become widely accepted techniques for
acoustic models in seismology and underwater acoustics. To date a generic form
of these procedures including fluid motion and time dependence has not appeared
in the literature. A detailed investigation of the characteristic curves of the
equations of hydrodynamics allows for an immediate generalization of the
procedure to be extracted from the equation form geodesic deviation. The
general paraxial ray trace equations serve as an ideal supplement to ordinary
ray tracing in predicting the deformation of acoustic beams in random
environments. The general procedure is derived in terms of affine
parameterization and in a coordinate time parameterization ideal for
application to physical acoustic ray propagation. The formalism is applied to
layered media, where the deviation equation reduces to a second order
differential equation for a single field with a general solution in terms of a
depth integral along the ray path. Some features are illustrated through
special cases which lead to exact solutions in terms of either ordinary or
special functions.


title: sPlot: a statistical tool to unfold data distributions

abstract:
  The paper advocates the use of a statistical tool dedicated to the
exploration of data samples populated by several sources of events. This new
technique, called sPlot, is able to unfold the contributions of the different
sources to the distribution of a data sample in a given variable. The sPlot
tool applies in the context of a Likelihood fit which is performed on the data
sample to determine the yields of the various sources.


title: On refinement of certain laws of classical electrodynamics

abstract:
  The problems considered refer to the material equations of electric- and
magnetoelectric induction. Some contradictions found in fundamental studies on
classical electrodynamics have been explained. The notion magnetoelectric
induction has been introduced, which permits symmetrical writing of the
induction laws. It is shown that the results of the special theory of
relativity can be obtained from these laws through the Galilean
transformations. The permittivity and permeability of materials media are shown
to be independent of frequency. The notions magnetoelectrokinetic and
electromagnetopotential waves and kinetic capacity have been introduced. It is
shown that along with the longitudinal Langmuir resonance, the transverse
resonance is possible in nonmagnetized plasma, and both the resonances are
degenerate. A new notion scalar-vector potential is introduced, which permits
solution of all present-day problems of classical electrodynamics. The use of
the scalar-vector potential makes the magnetic field notion unnecessary.


title: Finding two-dimensional peaks

abstract:
  Two-dimensional generalization of the original peak finding algorithm
suggested earlier is given. The ideology of the algorithm emerged from the well
known quantum mechanical tunneling property which enables small bodies to
penetrate through narrow potential barriers. We further merge this ``quantum''
ideology with the philosophy of Particle Swarm Optimization to get the global
optimization algorithm which can be called Quantum Swarm Optimization. The
functionality of the newborn algorithm is tested on some benchmark optimization
problems.


title:
Broken-Symmetry Unrestricted Hybrid Density Functional Calculations on
  Nickel Dimer and Nickel Hydride

abstract:
  In the present work we investigate the adequacy of broken-symmetry
unrestricted density functional theory (DFT) for constructing the potential
energy curve of nickel dimer and nickel hydride, as a model for larger bare and
hydrogenated nickel cluster calculations. We use three hybrid functionals: the
popular B3LYP, Becke's newest optimized functional Becke98, and the simple
FSLYP functional (50% Hartree-Fock and 50% Slater exchange and LYP
gradient-corrected correlation functional) with two basis sets: all-electron
(AE) Wachters+f basis set and Stuttgart RSC effective core potential (ECP) and
basis set.
  We find that, overall, the best agreement with experiment, comparable to that
of the high-level CASPT2, is obtained with B3LYP/AE, closely followed by
Becke98/AE and Becke98/ECP. FSLYP/AE and B3LYP/ECP give slightly worse
agreement with experiment, and FSLYP/ECP is the only method among the ones we
studied that gives an unaceptably large error, underestimating the dissociation
energy of nickel dimer by 28%, and being in the largest disagreement with the
experiment and the other theoretical predictions.


title: Transmission properties of left-handed band-gap structures

abstract:
  We analyze transmission of electromagnetic waves through a periodic band-gap
structure consisting of slabs of a left-handed metamaterial and air. Using the
effective parameters of the metamaterial derived from its microscopic
structure, we study, with the help of the transfer-matrix approach and by means
of the finite-difference-time-domain numerical simulations, the transmission
properties of such a left-handed photonic crystals in a novel type of band gap
associated with the zero averaged refractive index. We demonstrate that the
transmission can be made tunable by introducing defects, which allow to access
selectively two different types of band gaps.


title: The Black Holes do not exist - "Also Sprach Karl Schwarzschild"

abstract:
  According to the original theoretical analysis of 1916 by Karl Schwarzschild
the black holes do not have a physical reality.


title: DAFNE2: Lattice for a 2 GeV Electron Collider

abstract:
  Within the general frame of the upgrade of the collider DAFNE to the
neutron-antineutron energy threshold (2-2.5 GeV c.m.), modifications and
different options for the accelerator design are discussed and a possible
lattice for the Main Rings at 1 GeV is presented. The luminosity required by
the experiments for such a light quark factory is of the order of few 10^31
cm-2 s-1, easily achievable in the particle factory era.


title: Another Monte Carlo Renormalization Group Algorithm

abstract:
  A Monte Carlo Renormalization Group algorithm is used on the Ising model to
derive critical exponents and the critical temperature. The algorithm is based
on a minimum relative entropy iteration developed previously to derive
potentials from equilibrium configurations. This previous algorithm is modified
to derive useful information in an RG iteration. The method is applied in
several dimensions with limited success. Required accuracy has not been
achieved, but the method is interesting.


title: Symmetry-breaking in chiral polymerisation

abstract:
  We propose a model for chiral polymerisation and investigate its symmetric
and asymmetric solutions. The model has a source species which decays into
left- and right-handed types of monomer, each of which can polymerise to form
homochiral chains; these chains are susceptible to `poisoning' by the opposite
handed monomer. Homochiral polymers are assumed to influence the proportion of
each type of monomer formed from the precursor. We show that for certain
parameter values a positive feedback mechanism makes the symmetric steady-state
solution unstable. The kinetics of polymer formation are then analysed in the
case where the system starts from zero concentrations of monomer and chains. We
show that following a long induction time, extremely large concentrations of
polymers are formed for a short time, during this time an asymmetry introduced
into the system by a random external perturbation may be massively amplified.
The system then approaches one of the steady-state solutions described above.


title:
One million year old groundwater in the Sahara revealed by krypton-81
  and chlorine-36

abstract:
  Measurements of 81Kr/Kr in deep groundwater from the Nubian Aquifer (Egypt)
were performed by a new laser-based atom-counting method. 81Kr ages range from
\~2x10^5 to ~1x10^6 yr, correlate with 36Cl/Cl ratios, and are consistent with
lateral flow of groundwater from a recharge area near the Uweinat Uplift in SW
Egypt. Low delta-2H values of the 81Kr-dated groundwater reveal a recurrent
Atlantic moisture source during Pleistocene pluvial periods. These results
indicate that the 81Kr method for dating old groundwater is robust and such
measurements can now be applied to a wide range of hydrologic problems.


title: A Neural Bayesian Estimator for Conditional Probability Densities

abstract:
  This article describes a robust algorithm to estimate a conditional
probability density f(t|x) as a non-parametric smooth regression function. It
is based on a neural network and the Bayesian interpretation of the network
output as a posteriori probabability. The network is trained using example
events from history or simulation, which define the underlying probability
density f(t,x).
  Once trained, the network is applied on new, unknown examples x, for which it
can predict the probability distribution of the target variable t.
Event-by-event knowledge of the smooth function f(t|x) can be very useful, e.g.
in maximum likelihood fits or for forecasting tasks. No assumptions are
necessary about the distribution, and non-Gaussian tails are accounted for
automatically. Important quantities like median, mean value, left and right
standard deviations, moments and expectation values of any function of t are
readily derived from it.
  The algorithm can be considered as an event-by-event unfolding and leads to
statistically optimal reconstruction. The largest benefit of the method lies in
complicated problems, when the measurements x are only relatively weakly
correlated to the output t. As to assure optimal generalisation features and to
avoid overfitting, the networks are regularised by extended versions of weight
decay. The regularisation parameters are determined during the online-learning
of the network by relations obtained from Bayesian statistics.
  Some toy Monte Carlo tests and first real application examples from
high-energy physics and econometry are discussed.


title: Antisymmetric Tensor Fields, 4-Potentials and Indefinite Metrics

abstract:
  We generalize the Stueckelberg formalism in the (1/2,1/2) representation of
the Lorentz Group. Some relations to other modern-physics models are found.

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


title:
Planewave diffraction at the periodically corrugated boundary of vacuum
  and a negative phase-velocity material

abstract:
  Considering the diffraction of a plane wave by a periodically corrugated
half-space, we show that the transformation of the refracting medium from
positive/negative phase-velocity to negative/positive phase-velocity type has
an influence on the diffraction efficiencies. This effect increases with
increasing corrugation depth, owing to the presence of evanescent waves in the
troughs of the corrugated interface.


title:
Finite Difference Time Domain (FDTD) Simulations of Electromagnetic Wave
  Propagation Using a Spreadsheet

abstract:
  We describe a simple and intuitive implementation of the method of finite
difference time domain simulations for propagating electromagnetic waves using
the simplest possible tools available in Microsoft Excel. The method overcomes
the usual obstacles of familiarity with programming languages as it relies on
little more than the cut and paste features that are standard in Excel. Avenues
of exploration by students are proposed and sample graphs are included. The
pedagogical effectiveness of the implementation was tested during an
Independent Activities Period class, composed of 80% freshmen, at MIT, and
yielded positive results.


title: Cremonian Space-Time(s) as an Emergent Phenomenon

abstract:
  It is shown that the notion of fundamental elements can be extended to_any_,
i.e. not necessarily homaloidal, web of rational surfaces in a
three-dimensional projective space. A Cremonian space-time can then be viewed
as an_emergent_ phenomenon when the condition of "homaloidity" of the
corresponding web is satisfied. The point is illustrated by a couple of
particular types of "almost-homaloidal" webs of quadratic surfaces. In the
first case, the quadrics have a line and two distinct points in common and the
corresponding pseudo-Cremonian manifold is endowed with just two spatial
dimensions. In the second case, the quadrics share six distinct points, no
three of them collinear, that lie in quadruples in three different planes, and
the corresponding pseudo-Cremonian configuration features three time
dimensions. In both the cases, the limiting process of the emergence of generic
Cremonian space-times is explicitly demonstrated.


title: Full Hydrodynamic Simulation of GaAs MESFETs

abstract:
  A finite difference upwind discretization scheme in two dimensions is
presented in detail for the transient simulation of the highly coupled
non-linear partial differential equations of the full hydrodynamic model,
providing thereby a practical engineering tool for improved charge carrier
transport simulations at high electric fields and frequencies. The
discretization scheme preserves the conservation and transportive properties of
the equations. The hydrodynamic model is able to describe inertia effects which
play an increasing role in different fields of micro- and optoelectronics,
where simplified charge transport models like the drift-diffusion model and the
energy balance model are no longer applicable. Results of extensive numerical
simulations are shown for a two-dimensional MESFET device. A comparison of the
hydrodynamic model to the commonly used energy balance model is given and the
accuracy of the results is discussed.


title:
Bayesian Estimation for Land Surface Temperature Retrieval: The Nuisance
  of Emissivities

abstract:
  An approach to the remote sensing of land surface temperature is developed
using the methods of Bayesian inference. The starting point is the maximum
entropy estimate for the posterior distribution of radiance in multiple bands.
In order to convert this quantity to an estimator for surface temperature and
emissivity with Bayes' theorem, it is necessary to obtain the joint prior
probability for surface temperature and emissivity, given available prior
knowledge. The requirement that any pair of distinct observers be able to
relate their descriptions of radiance under arbitrary Lorentz transformations
uniquely determines the prior probability. Perhaps surprisingly, surface
temperature acts as a scale parameter, while emissivity acts as a location
parameter, giving the prior probability P(T,emissivity|K)=const./T dT
d(emissivity). Given this result, it is a simple matter to construct estimators
for surface temperature and emssivity. Monte Carlo simulations of land surface
temeprature retrieval in selected MODIS bands are presented as examples of the
utility of the approach.


title:
Phase shifts of synchronized oscillators and the systolic/diastolic
  blood pressure relation

abstract:
  We study the phase-synchronization properties of systolic and diastolic
arterial pressure in healthy subjects. We find that delays in the oscillatory
components of the time series depend on the frequency bands that are
considered, in particular we find a change of sign in the phase shift going
from the Very Low Frequency band to the High Frequency band. This behavior
should reflect a collective behavior of a system of nonlinear interacting
elementary oscillators. We prove that some models describing such systems, e.g.
the Winfree and the Kuramoto models offer a clue to this phenomenon. For these
theoretical models there is a linear relationship between phase shifts and the
difference of natural frequencies of oscillators and a change of sign in the
phase shift naturally emerges.


title:
Drag Reduction in Homogeneous Turbulence by Scale-Dependent Effective
  Viscosity

abstract:
  The phenomenon of drag reduction by polymer additives had been studied in
simulations on the basis of non-Newtonian fluid mechanical models that take
into account the field of polymer extension (conformation tensor) and its
interaction with the velocity field. Drag reduction was found in both
homogeneous and wall bounded turbulent flows. In the latter case it was shown
recently that the notion of scale-dependent effective viscosity allows
quantitative predictions of the characteristics of drag reduction in close
correspondence with experiments. In this paper we demonstrate that also drag
reduction in homogeneous turbulence is usefully discussed in terms of a
scale-dependent viscosity. In other words, the essence of the phenomena under
study can be recaptured by an "equivalent" equation of motion for the velocity
field alone, with a judiciously chosen scale-dependent effective viscosity that
succinctly summarizes the important aspects of the interaction between the
polymer conformation tensor field and the velocity field. We will also clarify
here the differences between drag reduction in homogeneous and wall bounded
flows.


title:
Molecular structures and vibrations of neutral and anionic CuOx (x =
  1-3,6) clusters

abstract:
  We report equilibrium geometric structures of CuO2, CuO3, CuO6, and CuO
clusters obtained by an all-electron linear combination of atomic orbitals
scheme within the density-functional theory with generalized gradient
approximation to describe the exchange-correlation effects. The vibrational
stability of all clusters is examined on the basis of the vibrational
frequencies. A structure with Cs symmetry is found to be the lowest-energy
structure for CuO2, while a -shaped structure with C2v symmetry is the most
stable structure for CuO3. For the larger CuO6 and CuO clusters, several
competitive structures exist with structures containing ozonide units being
higher in energy than those with O2 units. The infrared and Raman spectra are
calculated for the stable optimal geometries. ~


title: Are hemispherical caps of boron-nitride nanotubes possible?

abstract:
  We report all-electron, density-functional calculations with large Gaussian
polarization basis set of the recently synthesized octahedral B24N24 cage that
is perfectly round by symmetry, and boron-nitride (BN) clusters that its
existence might suggest. We consider whether it is energetically possible that
the two halves of this round cage could cap the BN nanotubes, modeled by B28N28
and B32N32. The energetics show that BN nanotubes with such round caps, are
only slightly less favorable than the BN clusters containing six squares as the
only defects in the otherwise perfect hexagonal lattice. A larger B96N96
octahedral cage formed from B24N24 by adding sufficient hexagons to isolate all
squares is not very favorable energetically. The squares protrude noticeably
from its otherwise round surface.


title: Stability of As$_n$ [n=4, 8, 20, 28, 32, 36, 60] Cage Structures

abstract:
  We present all-electron density functional study of the geometry, electronic
structure, vibrational modes, polarizabilities as well as the infrared and
Raman spectra of fullerene-like arsenic cages. The stability of As$_n$ cages
for sizes 4, 8, 20, 28, 32, 36, and 60 wherein each As atom is three-fold
coordinated is examined. We find that all the cages studied are vibrationally
stable and while all the clusters are energetically stable with respect to
isolated arsenic atoms, only As$_{20}$ is energetically stable against
dissociation into As$_4$. We suggest that the Raman spectra might be a means
for observing the As$_{20}$ molecule in gas phase.


title: The Many Dimensions of Dimension

abstract:
  Some aspects of the history and impact of the dimension revolution are
briefly surveyed, starting with Nordstrom's D=5 scalar gravity-electromagnetism
unification.


title:
Creating a self-induced dark spontaneous-force optical trap for neutral
  atoms

abstract:
  This communication describes the observation of a new type of dark
spontaneous-force optical trap (dark SPOT) obtained without the use of a mask
blocking the central part of the repumper laser beam. We observe that loading a
magneto-optical trap (MOT) from a continuous and intense flux of slowed atoms
and by appropriately tuning the frequency of the repumper laser is possible to
achieve basically the same effect of the dark SPOT, using a simpler apparatus.
This work characterizes the new system through measurements of absorption and
fluorescence imaging of the atomic cloud and presents a very simple model to
explain the main features of our observations. We believe that this new
approach may simplify the current experiments to produce quantum degenerated
gases.


title: Dynamic tunnelling ionization of $H_2^+$ in intense fields

abstract:
  Intense-field ionization of the hydrogen molecular ion by linearly-polarized
light is modelled by direct solution of the fixed-nuclei time-dependent
Schr\"odinger equation and compared with recent experiments. Parallel
transitions are calculated using algorithms which exploit massively parallel
computers. We identify and calculate dynamic tunnelling ionization resonances
that depend on laser wavelength and intensity, and molecular bond length.
Results for $\lambda \sim 1064$ nm are consistent with static tunnelling
ionization. At shorter wavelengths $\lambda \sim 790 $ nm large dynamic
corrections are observed. The results agree very well with recent experimental
measurements of the ion spectra. Our results reproduce the single peak
resonance and provide accurate ionization rate estimates at high intensities.
At lower intensities our results confirm a double peak in the ionization rate
as the bond length varies.

categories: physics.comp-ph physics.atom-ph physics.chem-ph quant-ph


title: A discrete time-dependent method for metastable atoms in intense fields

abstract:
  The full-dimensional time-dependent Schrodinger equation for the electronic
dynamics of single-electron systems in intense external fields is solved
directly using a discrete method.
  Our approach combines the finite-difference and Lagrange mesh methods. The
method is applied to calculate the quasienergies and ionization probabilities
of atomic and molecular systems in intense static and dynamic electric fields.
The gauge invariance and accuracy of the method is established. Applications to
multiphoton ionization of positronium and hydrogen atoms and molecules are
presented. At very high intensity above saturation threshold, we extend the
method using a scaling technique to estimate the quasienergies of metastable
states of the hydrogen molecular ion. The results are in good agreement with
recent experiments.

categories: physics.atom-ph math-ph math.MP physics.chem-ph physics.comp-ph


title: Electronic Structure of Atoms in Magnetic Quadrupole Traps

abstract:
  We investigate the electronic structure and properties of atoms exposed to a
magnetic quadrupole field. The spin-spatial as well as generalized time
reversal symmetries are established and shown to lead to a two-fold degeneracy
of the electronic states in the presence of the field. Low-lying as well as
highly excited Rydberg states are computed and analyzed for a broad regime of
field gradients. The delicate interplay between the Coulomb and various
magnetic interactions leads to complex patterns of the spatial spin
polarization of individual excited states. Electromagnetic transitions in the
quadrupole field are studied in detail thereby providing the selection rules
and in particular the transition wavelengths and corresponding dipole
strengths. The peculiar property that the quadrupole magnetic field induces
permanent electric dipole moments of the atoms is derived and discussed.


title:
Topological spin transport of photons: the optical Magnus Effect and
  Berry Phase

abstract:
  The paper develops a modified geometrical optics (GO) of smoothly
inhomogeneous isotropic medium, which takes into account two topological
phenomena: Berry phase and the optical Magnus effect. By using the analogy
between a quasi-classical motion of a quantum particle with a spin and GO of an
electromagnetic wave in smoothly inhomogeneous media, we have introduced the
standard gauge potential associated with the degeneracy in the wave momentum
space. This potential corresponds to the Dirac-monopole-like field (Berry
curvature), which causes the topological spin (polarization) transport of
photons. The deviations of waves of right-hand and left-hand helicity occur in
the opposite directions and orthogonally to the principal direction of motion.
This produces a spin current directed across the principal motion. The
situation is similar to the anomalous Hall effect for electrons. In addition, a
simple scheme of the experiment allowing one to observe the topological spin
splitting of photons has been suggested.


title: Hyperbolical geometric quantum phase and topological dual mass

abstract:
  In this note we show the existence of the hyperbolical geometric quantum
phase that is different from the ordinary trigonometric geometric quantum
phase. Gravitomagnetic charge (dual mass) is the gravitational analogue of
magnetic monopole in Electrodynamics; but, as will be shown here, it possesses
more interesting and significant features, {\it e.g.}, it may constitute the
dual matter that has different gravitational properties compared with mass. In
order to describe the space-time curvature due to the topological dual mass, we
construct the dual Einstein's tensor. Further investigation shows that
gravitomagnetic potentials caused by dual mass are respectively analogous to
the trigonometric and hyperbolic geometric phase. The study of the geometric
phase and dual mass provides a valuable insight into the time evolution of
quantum systems and the topological properties in General Relativity.


title:
On the Reliability of the Geomagnetic Quake as Short Time Earthquake
  Precursor for Sofia Region- 2002, 2003

abstract:
  The local when earthquake prediction is based on the connection between
geomagnetic quakes and the next incoming minimum or maximum of tidal
gravitational potential. The probability time window for the predicted
earthquake is for the tidal minimum approximately +/-1 day and for the maximum-
+/-2 days. The preliminary statistic estimation on the basis of distribution of
the time difference between occurred and predicted earthquakes for the period
2002- 2003 for Sofia region is given. The possibility for creating a local
when, where earthquake research and prediction NETWORK is based on the accurate
monitoring of the electromagnetic field with special space and time scales
under, on and over the Earth surface. The periodically upgraded information
from seismic hazard maps and other standard geodetic information as well as
other precursory information is essential.


title: Local Blockade of Rydberg Excitation in an Ultracold Gas

abstract:
  In the laser excitation of ultracold atoms to Rydberg states, we observe a
dramatic suppression caused by van der Waals interactions. This behavior is
interpreted as a local excitation blockade: Rydberg atoms strongly inhibit
excitation of their neighbors. We measure suppression, relative to isolated
atom excitation, by up to a factor of 6.4. The dependence of this suppression
on both laser irradiance and atomic density are in good agreement with a
mean-field model. These results are an important step towards using ultracold
Rydberg atoms in quantum information processing.


title: One-Dimensional Motion of Bethe-Johnson Gas

abstract:
  A one dimensional motion of the Bethe-Johnson gas is studied in a context of
Landau's hydrodynamical model of a nucleus-nucleon collision. The expressions
for the entropy change, representing a generalization of the previously known
results, are found. It is shown that these expressions strongly depend on an
equation of state for the baryonic matter.


title: Technical design and performance of the NEMO3 detector

abstract:
  The development of the NEMO3 detector, which is now running in the Frejus
Underground Laboratory (L.S.M. Laboratoire Souterrain de Modane), was begun
more than ten years ago. The NEMO3 detector uses a tracking-calorimeter
technique in order to investigate double beta decay processes for several
isotopes. The technical description of the detector is followed by the
presentation of its performance.


title:
Production and state-selective detection of ultracold, ground state RbCs
  molecules

abstract:
  Using resonance-enhanced two-photon ionization, we detect ultracold,
ground-state RbCs molecules formed via photoassociation in a laser-cooled
mixture of 85Rb and 133Cs atoms. We obtain extensive bound-bound excitation
spectra of these molecules, which provide detailed information about their
vibrational distribution, as well as spectroscopic data on the RbCs ground
a^3\Sigma^+ and excited (2)^3\Sigma^+, (1)^1\Pi states. Analysis of this data
allows us to predict strong transitions from observed excited levels to the
absolute vibronic ground state of RbCs, potentially allowing the production of
stable, ultracold polar molecules at rates as large as 10^7 s^{-1}.


title:
Elimination of High-Energy Divergence in Relativistic Lagrangean
  Formulation of Gravitating Particle Dynamics

abstract:
  The nonrenormalizable singularity of the gravitational 1/r potential at
ralativistic and quantum levels is a longstanding problem of modern physics.
The problem is discussed in Relativistic Lagrangean framework with the variable
proper mass. It is shown that the so-called self-energy divergence for the 1/r
graviational potntial can be eliminated within the variable proper mass
concept. The problem has many aspects outlined, which should be further
investigated before the final conclusion could be made.


title: Space Rotation Theory

abstract:
  The theory of Space rotations is introduced. The relativity principle is
generalized to satisfy to reference frames rotating in 3D space. It is shown
that the most postulates and limitations of quantum theories are consequences
of this extended relativity principle. The mathematical, physical and
philosophical aspects of the Space rotation theory are discussed.


title: Toy Blocks and Rotational Physics

abstract:
  In this paper we summarize the theory of the "falling chimney," which deals
with the breaking of tall structures in mid-air, when they fall to the ground.
We describe how to reproduce these effects using small-scale models built with
toy blocks. We also present an improved and more effective way to perform and
analyze these interesting experiments, by using video capture software together
with a digital video camera.


title:
Comparison of two single-ion optical frequency standards at the
  sub-Hertz level

abstract:
  We describe experimental investigations on an optical frequency standard
based on a laser cooled 171Yb+ ion confined in a radiofrequency Paul trap. The
electric-quadrupole transition from the 2S1/2(F=0) ground state to the
2D3/2(F=2) state at the wavelength of 436 nm is used as the reference
transition. The reference transition is probed by a frequency-doubled,
frequency-stabilized diode laser and is resolved with a Fourier-limited full
halfwidth of approximately 30 Hz. In order to compare two 171Yb+ standards,
separate frequency shift and servo systems are employed to stabilise the probe
frequency to the reference transition line centers of two independently stored
171Yb+ ions. The present experimental results indicate a relative instability
(Allan standard deviation)of the optical frequency difference between
the two systems of sigma_y(1000 s)=1.0E-15 and a mean frequency difference of
0.2 Hz. Shifts in the range of several Hertz are observed in the frequency
difference if a stationary electric field gradient is superimposed on the
radiofrequency trap field. This measurement permits a first experimental
estimate of the electric quadrupole moment of the 2D3/2 state of Yb+.


title:
Charge Transfer and Charge Broadening of GEM Structures in High Magnetic
  Fields

abstract:
  We report on measurements of charge transfer in GEM structures in high
magnetic fields. These were performed in the framework of the R&D work for a
Time Projection Chamber at a future Linear Collider. A small test chamber has
been installed into the aperture of a superconducting magnet with the GEM
structures mounted perpendicular to the B field direction. The charge transfer
is derived from the electrical currents monitored during irradiation with an
${}^{55}$Fe source. No severe loss of primary ionisation charge is observed,
but an improved ion feedback suppression is achieved for high magnetic fields.
Additionally, the width of the charge cloud released by individual ${}^{55}$Fe
photons is measured using a finely segmented strip readout after the triple GEM
structure. Charge widths between 0.3 and 0.5 mm RMS are observed, which
originate from the charge broadening inside the GEM readout. This charge
broadening is only partly suppressed at high magnetic fields.


title:
Isolated Electrostatic Structures Observed Throughout the Cluster Orbit:
  Relationship to Magnetic Field Strength

abstract:
  Isolated electrostatic structures are observed throughout much of the 4 Re by
19.6 Re Cluster orbit. These structures are observed in the Wideband plasma
wave instrument's waveform data as bipolar and tripolar pulses. These
structures are observed at all of the boundary layers, in the solar wind and
magnetosheath, and along auroral field lines at 4.5-6.5 Re. Using the Wideband
waveform data from the various Cluster spacecraft we have carried out a survey
of the amplitudes and time durations of these structures and how these
quantities vary with the local magnetic field strength. Such a survey has not
been carried out before, and it reveals certain characteristics of solitary
structures in a finite magnetic field, a topic still inadequately addressed by
theories. We find that there is a broad range of electric field amplitudes at
any specific magnetic field strength, and there is a general trend for the
electric field amplitudes to increase as the strength of the magnetic field
increases over a range of 5 to 500 nT. We provide a possible explanation for
this trend that releates to the structures being Bernstein-Greene-Kruskal mode
solitary waves. There is no corresponding dependence of the duration of the
structures on the magnetic field strength, although a plot of these two
quantities reveals the unexpected result that with the exception of the
magnetosheath, all of the time durations for all of the other regions are
comparable, wheras the magnetosheath time durations clearly are in a different
category of much smaller time duration. We speculate that this implies the
structures are much smaller in size.


title:
Off-diagonal impedance in amorphous wires and application to linear
  magnetic sensors

abstract:
  The magnetic-field behaviour of the off-diagonal impedance in Co-based
amorphous wires is investigated under the condition of sinusoidal (50 MHz) and
pulsed (5 ns rising time) current excitations. For comparison, the field
characteristics of the diagonal impedance are measured as well. In general,
when an alternating current is applied to a magnetic wire the voltage signal is
generated not only across the wire but also in the coil mounted on it. These
voltages are related with the diagonal and off-diagonal impedances,
respectively. It is demonstrated that these impedances have a different
behaviour as a function of axial magnetic field: the former is symmetrical and
the latter is antisymmetrical with a near linear portion within a certain field
interval. In the case of the off-diagonal response, the dc bias current
eliminating circular domains is necessary. The pulsed excitation that combines
both high and low frequency harmonics produces the off-diagonal voltage
response without additional bias current or field. This suits ideal for a
practical sensor circuit design. The principles of operation of a linear
magnetic sensor based on C-MOS transistor circuit are discussed.


title:
Possibility of an ultra-precise optical clock using the $6 ^1S_0 \to 6
  ^3P^o_0$ transition in $^{171, 173}$Yb atoms held in an optical lattice

abstract:
  We report calculations designed to assess the ultimate precision of an atomic
clock based on the 578 nm $6 ^1S_0 --> 6 ^3P^o_0$ transition in Yb atoms
confined in an optical lattice trap. We find that this transition has a natural
linewidth less than 10 mHz in the odd Yb isotopes, caused by hyperfine
coupling. The shift in this transition due to the trapping light acting through
the lowest order AC polarizability is found to become zero at the magic trap
wavelength of about 752 nm. The effects of Rayleigh scattering, higher-order
polarizabilities, vector polarizability, and hyperfine induced electronic
magnetic moments can all be held below a mHz (about a part in 10^{18}), except
in the case of the hyperpolarizability larger shifts due to nearly resonant
terms cannot be ruled out without an accurate measurement of the magic
wavelength.


title:
Experimental observation and characterization of the magnetorotational
  instability

abstract:
  Differential rotation occurs in conducting flows in accretion disks and
planetary cores. In such systems, the magnetorotational instability can arise
from coupling Lorentz and centrifugal forces to cause large radial angular
momentum fluxes. We present the first experimental observation of the
magnetorotational instability. Our system consists of liquid sodium between
differentially rotating spheres, with an imposed coaxial magnetic field. We
characterize the observed patterns, dynamics and torque increases, and
establish that this instability can occur from a hydrodynamic turbulent
background.


title:
Development of a multi-pixel hybrid photo-detector with high quantum
  efficiency and gain

abstract:
  A hybrid photo-detector (HPD) consisting of a photocathode and a multi-pixel
avalanche diode (MP-AD) was developed a few years ago. Our previous studies
showed that its inherent potential for high resolution photon counting could be
further enhanced by reducing fluctuations in charge loss in the dead layer at
the entrance of the MP-AD. In this paper, we report on the improvement with the
newly developed HPD whose encapsulated MP-AD has a thinner dead layer than
before. It is demonstrated that the new HPD has much better energy resolution,
which enables clearer counting up to nine photoelectrons. Further enhancement
of the photocathode sensitivity of the HPD is also discussed.


title: Atom lithography with two-dimensional optical masks

abstract:
  With a two-dimensional (2D) optical mask, nanoscale patterns are created for
the first time in an atom lithography process using metastable helium atoms.
The internal energy of the atoms is used to locally damage a hydrofobic resist
layer, which is removed in a wet etching process. Experiments have been
performed with several polarizations for the optical mask, resulting in
different intensity patterns, and corresponding nanoscale structures. The
results for a linear polarized light field show an array of holes with a
diameter of 260 nm, in agreement with a computed pattern. With a circularly
polarized light field a line pattern is observed with a spacing of 766 nm.
Simulations taking into account many possible experimental imperfections can
not explain this pattern.


title:
Relativistic electronic dressing in laser-assisted ionization of atomic
  hydrogen by electron impact

abstract:
  Within the framework of the coplanar binary geometry where it is justified to
use plane wave solutions for the study of the $(e,2e)$ reaction and in the
presence of a circularly polarized laser field, we introduce as a first step
the DVRPWBA1 (Dirac-Volkov Plane Wave Born Approximation1) where we take into
account only the relativistic dressing of the incident and scattered electrons.
Then, we introduce the DVRPWBA2 (Dirac-Volkov Plane Wave Born Approximation2)
where we take totally into account the relativistic dressing of the incident,
scattered and ejected electrons. We then compare the corresponding triple
differential cross sections for laser-assisted ionization of atomic hydrogen by
electron impact both for the non relativistic and the relativistic regime.


title: Mott scattering in strong laser field revisited

abstract:
  In this work, we review and correct the first Born differential cross section
for the process of Mott scattering of a Dirac-Volkov electron, namely, the
expression (26) derived by Szymanowski et al [Physical Review A {\bf 56}, 3846
(1997)]. In particular, we disagree with the expression of
$(\frac{d\sigma}{d\Omega})$ they obtained and we give the exact coefficients
multiplying the various Bessel functions appearing in the scattering
differential cross section. Comparison of our numerical calculations with those
of Szymanowski et al. shows qualitative and quantitative differences when the
incoming total electron energy and the electric field strength are increased
particularly in the direction of the laser propagation. Such corrections are
very important since the relativistic electronic dressing of any Dirac-Volkov
charged particle gives rise to these coefficients that multiply the various
Bessel functions and the relativistic study of other processes (such as
excitation, ionisation, etc....) depends strongly of the correctness and
reliability of the calculations for this process of Mott Scattering in presence
of a laser field. Our work has been accepted [Y. Attaourti, B. Manaut, Physical
Review A {\bf 68}, 067401 (2003)] but only as a comment. In this paper, we give
the full details of the calculations as well as the clear explanation of the
large discrepancies that their results could cause when working in the ultra
relativistic regime and using a very strong laser field corresponding to an
electric field $\varepsilon=5.89$ in atomic units.


title: The Shape and Stability of a Viscous Thread

abstract:
  When a viscous fluid, like oil or syrup, streams from a small orifice and
falls freely under gravity, it forms a long slender thread, which can be
maintained in a stable, stationary state with lengths up to several meters. We
shall discuss the shape of such liquid threads and their surprising stability.
It turns out that the strong advection of the falling fluid can almost outrun
the Rayleigh-Plateau instability. Even for a very viscous fluid like sirup or
silicone oil, the asymptotic shape and stability is independent of viscosity
and small perturbations grow with time as $\exp({{\rm C} t^{{1/4}}})$, where
the constant is independent of viscosity. The corresponding spatial growth has
the form $\exp({(z/L)^{{1/8}}})$, where $z$ is the down stream distance and $L
\sim Q^2 \sigma^{-2} g$ and where $\sigma$ is the surface tension, $g$ is the
gravity and $Q$ is the flux. However, the value of viscosity determines the
break-up length of a thread $L_{\nu} \sim \nu^{1/4}$ and thus the possibility
of observing the $\exp({{\rm C} t^{{1/4}}})$ type asymptotics.


title: Electron identification performance with ALICE TRD prototypes

abstract:
  We present the electron/pion identification performance measured with
prototypes for ALICE TRD. Measured spectra of energy deposit of pions and
electrons as well as their average values are presented and compared to
calculations. Various radiators are investigated over the momentum range of 1
to 6 GeV/c. The time signature of TR is exploited in a bidimensional likelihood
mothod.


title:
New limit on the present temporal variation of the fine structure
  constant

abstract:
  The comparison of different atomic transition frequencies over time can be
used to determine the present value of the temporal derivative of the fine
structure constant alpha in a model-independent way without assumptions on
constancy or variability of other parameters. We have measured an optical
transition frequency at 688 THz in ^{171}Yb+ with a cesium atomic clock at two
times separated by 2.8 years and find a value for the fractional variation of
the frequency ratio $f_{\rm Yb}/f_{\rm Cs}$ of $(-1.2\pm 4.4)\cdot 10^{-15}$
yr$^{-1}$, consistent with zero. Combined with recently published values for
the constancy of other transition frequencies this measurement sets an upper
limit on the present variability of alpha at the level of $2.0\cdot 10^{-15}$
yr$^{-1}$, corresponding so far to the most stringent limit from laboratory
experiments.


title:
Excitation energies, oscillator strengths, and lifetimes of levels along
  the gold isoelectronic sequence

abstract:
  Energies of ns[1/2] (n= 6-9), np[j] (n = 6-8), nd[j] (n= 6-7), and 5f[j]
states in neutral Au and Au-like ions with nuclear charges Z = 80 - 83 are
calculated using relativistic many-body perturbation theory. Reduced matrix
elements, oscillator strengths, transition rates and lifetimes are determined
for the 30 possible nl[j]-n'l'[j'] electric-dipole transitions. Results for a
limited number states ns[1/2], np[j] (n= 6-7) and 6d[j] are obtained in the
relativistic single-double (SD) approximation, where single and double
excitations of Dirac-Fock wave functions are included to all orders in
perturbation theory. Using SD wave functions, accurate values are obtained for
energies of the eight lowest states and for the fourteen possible
electric-dipole matrix elements between these states. With the aid of the SD
wave functions, we also determine transition rates and oscillator strengths for
the fourteen transitions together with lifetimes of 6p[j], 7p[j], and 6d[j]
levels. We investigate the hyperfine structure in HgII and TlIII. The hyperfine
A-values are determined for 6s[1/2] and 6p[j] states in 199Hg+, 201Hg+, and
205Tl++ isotopes. These calculations provide a theoretical benchmark for
comparison with experiment and theory.


title: Flutter of a Flag

abstract:
  We give an explanation for the onset of wind-induced flutter in a flag. Our
theory accounts for the various physical mechanisms at work: the finite length
and the small but finite bending stiffness of the flag, the unsteadiness of the
flow, the added mass effect and vortex shedding from the trailing edge. Our
analysis allows us to predict a critical speed for the onset of flapping as
well as the frequency of flapping. We find that in a particular limit
corresponding to a low density fluid flowing over a soft high density flag, the
flapping instability is akin to a resonance between the mode of oscillation of
a rigid pivoted airfoil in a flow and a hinged-free elastic filament vibrating
in its lowest mode.


title:
General-Relativistic Equations of Motion in terms of Energy and Angular
  Momentum

abstract:
  An attempt is made to describe the general-relativistic equations of motion
for the Schwarzschild geometry in terms of the classical concepts of energy and
angular momentum. Using the customary terms the geodesic equations can be
viewed in a way that is very helpful in providing the physical meaning of the
mathematical development.


title: Mid-Infrared Radiation as a Short-Term Earthquake Precursor

abstract:
  Recently it has been found by F. Freund that the granite under high pressure
undergoes a phase transition from insulator to a p-type semiconductor. This
phase transition is a key concept to understanding pre-earthquake phenomena.
This effect accompanies with the radiation of the granite in the mid-infrared
region. we were able to predict the recent earthquake in the south of Iran by
monitoring this radiation.


title: Trajectory structures and transport

abstract:
  The special problem of transport in 2-dimensional divergence-free stochastic
velocity fields is studied by developing a statistical approach, the nested
subensemble method. The nonlinear process of trapping determined by such fields
generates trajectory structures whose statistical characteristics are
determined. These structures strongly influence the transport.


title:
Modeling turbulent wave-front phase as a fractional Brownian motion: a
  new approach

abstract:
  This paper introduces a general and new formalism to model the turbulent
wave-front phase using fractional Brownian motion processes. Moreover, it
extends results to non-Kolmogorov turbulence. In particular, generalized
expressions for the Strehl ratio and the angle-of-arrival variance are
obtained. These are dependent on the dynamic state of the turbulence.


title:
Experimental study of nonlinear focusing in a magneto-optical trap using
  a Z-scan technique

abstract:
  We present an experimental study of Z-scan measurements of the nonlinear
response of cold Cs atoms in a magneto-optical trap. Numerical simulations of
the Z-scan signal accounting for the nonuniform atomic density agree with
experimental results at large probe beam detunings. At small probe detunings a
spatially varying radiation force modifies the Z-scan signal. We also show that
the measured scan is sensitive to the atomic polarization distribution.


title:
Interferometric differentiation between resonant Coherent Anti-Stokes
  Raman Scattering and nonresonant four-wave-mixing processes

abstract:
  A major impediment of using Coherent Anti-Stokes Raman Scattering to identify
biological molecules is that the illumination levels required to produce a
measurable signal often also produce significant nonresonant background from
the medium, especially from water, that is not specific to the resonance being
investigated. We present a method of using nonlinear interferometry to measure
the temporal shape of the anti-Stokes signal to differentiate which components
are resonant and nonresonant. This method is easily adaptable to most existing
pulsed CARS illumination methods and should allow for distinguishing resonant
CARS when using higher energy pulses. By examining the differences between
signals produced by acetone and water, we show that the resonant and
nonresonant signals can be clearly differentiated.


title:
Optical measurement of torque exerted on an elongated object by a
  non-circular laser beam

abstract:
  We have developed a scheme to measure the optical torque, exerted by a laser
beam on a phase object, by measuring the orbital angular momentum of the
transmitted beam. The experiment is a macroscopic simulation of a situation in
optical tweezers, as orbital angular momentum has been widely used to apply
torque to microscopic objects. A hologram designed to generate LG02 modes and a
CCD camera are used to detect the orbital component of the beam. Experimental
results agree with theoretical numerical calculations, and the strength of the
orbital component suggest its usefulness in optical tweezers for
micromanipulation.


title:
Cosmological Variation of the Fine Structure Constant versus a new
  Interaction

abstract:
  We show why a dynamically varying fine structure constant does not impact on
the Webb group's analysis as suggested by Bekenstein. We also provide a limit
on the size of a possible correction to the Dirac Hamiltonian caused by a
perturbation due to a dynamically varying alpha in hydrogen.


title:
Statement of problem on vortical inviscid flow of barotropic and
  incompressible fluids

abstract:
  The question what information is necessary for determination of a unique
solution of hydrodynamic equations for ideal fluid is investigated. Arbitrary
inviscid flows of the barotropic fluid and of incompressible fluid are
considered. After integrating hydrodynamic equations, all information on the
fluid flow is concentrated in dynamic equations in the form of indefinite
functions, whereas the initial and boundary conditions contain information on
the fluid particle labeling. It is shown that for determination of the
stationary flow of the incompressible fluid the vorticity on any stream line
must be given. Giving the velocity on the boundary, one does not determine the
vorticity, in general. If there are closed stream lines, the vorticity cannot
be given on them via boundary conditions. This circumstance explains existence
of different stationary vortical flows under the same boundary conditions.


title:
Power-Law Slip Profile of the Moving Contact Line in Two-Phase
  Immiscible Flows

abstract:
  Large scale molecular dynamics (MD) simulations on two-phase immiscible flows
show that associated with the moving contact line, there is a very large $1/x$
partial-slip region where $x$ denotes the distance from the contact line. This
power-law partial-slip region is verified in large-scale adaptive continuum
simulations based on a local, continuum hydrodynamic formulation, which has
proved successful in reproducing MD results at the nanoscale. Both MD and
continuum simulations indicate the existence of a universal slip profile in the
Stokes-flow regime, well described by $v^{slip}(x)/V_w=1/(1+{x}/{al_s})$, where
$v^{slip}$ is the slip velocity, $V_w$ the speed of moving wall, $l_s$ the slip
length, and $a$ is a numerical constant. Implications for the contact-line
dissipation are discussed.


title: A note on the polarization of the laser field in Mott Scattering

abstract:
  In the first Born approximation and using an elliptically polarized laser
field, the Mott scattering of an electron by a Coulomb potential is
investigated using the Dirac-Volkov states to describe the incident and
scattered electrons. The results obtained are compared with the results of S.M.
Li \textit{et al} \cite{1} for the case of a linearly polarized laser field and
with the results of Y. Attaourti \textit{et al} \cite{2} for the case of a
circular polarization.


title:
Optical parametric oscillators in isotropic photonic crystals and
  cavities: 3D time domain analysis

abstract:
  We investigate optical parametric oscillations through four-wave mixing in
resonant cavities and photonic crystals. The theoretical analysis underlines
the relevant features of the phenomenon and the role of the density of states.
Using fully vectorial 3D time-domain simulations, including both dispersion and
nonlinear polarization, for the first time we address this process in a face
centered cubic lattice and in a photonic crystal slab. The results lead the way
to the development of novel parametric sources in isotropic media.


title: DAFNE

abstract:
  The results of 2002 DAFNE operation for the two experiments KLOE and DEAR are
described. During 2003 a long shutdown has been dedicated to the installation
of new Interaction Regions (IR) and to hardware modifications and upgrades. In
the last section optics studies and performances expectations for the new
machine configuration are reported.


title:
Bose-Einstein Condensation of Particle-Hole Pairs in Ultracold Fermionic
  Atoms Trapped within Optical Lattices

abstract:
  We investigate the Bose-Einstein condensation (BEC, superfluidity) of
particle-hole pairs in ultracold Fermionic atoms with repulsive interactionsand
arbitrary polarization, which are trapped within optical lattices. Near a
Feshbach resonance, the dynamics of particle-hole pairs can be described by a
hard-core Bose-Hubbard model. The insulator - superfluid and
charge-density-wave (CDW) - superfluid phase transitions can be induced by
decreasing and increasing the potential depths with controlling the trapping
laser intensity, respectively. The parameter and polarization dependence of the
critical temperatures for the ordered states (BEC and/or CDW) is discussed
simultaneously.


title:
Small rare gas clusters in laser fields: ionisation and absorption at
  long and short laser wavelengths

abstract:
  The interaction of short laser pulses with small rare gas clusters is
investigated by using a microscopic, semi-classical model with an explicit
treatment of the inner-atomic dynamics. Field and collisional ionisation as
well as recombination are incorporated self-consistently so that the use of
rates for these processes could be avoided. The laser absorption and ionisation
mechanisms in clusters at near-infrared (800nm) and VUV wavelength (100nm) are
analysed.


title: Estimate of drainage water behaviour in shallow lakes

abstract:
  A theoretical estimate of the explicit time dependence of a drainage water of
shallow lakes is presented as an important contribution for understanding the
lake dynamics. This information can be obtained from a sum of functions,
largely used in fitting of experimental data. These functions were chosen
because their centre and weight yield a good description of the water basin
behaviour. The coefficients of these functions are here extracted using results
of measured and / or calculated data for the state variables describing the
shallow West Lake, Hangzou. This procedure can also be applied to other shallow
lakes, generating geological information about their drainage basin, which is
one of the most important parameters to describe their micrometeorological
behaviour. One concludes this work emphasizing the relevance of the explicit
time dependence of the drainage variables and the requirement of measured data
to validate this approach.


title:
Stability studies of nanosecond light sources based on blue ultra bright
  LEDs

abstract:
  We present the results of stability studies of nanosecond light sources based
on single quantum well (SQW) InGaN/GaN ultra bright blue LEDs. It is shown that
the light yield of such light sources and their timing characteristics don't
deteriorate even after 10^10 total pulses. The longterm stability of the
sources light yield is better than 1%.


title:
Reading a GEM with a VLSI pixel ASIC used as a direct charge collecting
  anode

abstract:
  In MicroPattern Gas Detectors (MPGD) when the pixel size is below 100 micron
and the number of pixels is large (above 1000) it is virtually impossible to
use the conventional PCB read-out approach to bring the signal charge from the
individual pixel to the external electronics chain. For this reason a custom
CMOS array of 2101 active pixels with 80 micron pitch, directly used as the
charge collecting anode of a GEM amplifying structure, has been developed and
built. Each charge collecting pad, hexagonally shaped, realized using the top
metal layer of a deep submicron VLSI technology is individually connected to a
full electronics chain (pre-amplifier, shaping-amplifier, sample and hold,
multiplexer) which is built immediately below it by using the remaining five
active layers. The GEM and the drift electrode window are assembled directly
over the chip so the ASIC itself becomes the pixelized anode of a MicroPattern
Gas Detector. With this approach, for the first time, gas detectors have
reached the level of integration and resolution typical of solid state pixel
detectors. Results from the first tests of this new read-out concept are
presented. An Astronomical X-Ray Polarimetry application is also discussed.


title: The role of wire imperfections in micro magnetic traps for atoms

abstract:
  We present a quantitative study of roughness in the magnitude of the magnetic
fieldproduced by a current carrying microwire, i.e. in the trapping potential
for paramagnetic atoms.We show that this potential roughness arises from
deviations in the wire current flow due to geometric fluctuations of the edges
of the wire : a measurement of the potentialusing cold trapped atoms agrees
with the potential computed from the measurement of the wire edge roughness by
a scanning electronmicroscope.


title: Orbital angular momentum exchange in an optical parametric oscillator

abstract:
  We present a study of orbital angular momentum transfer from pump to
down-converted beams in a type-II Optical Parametric Oscillator. Cavity and
anisotropy effects are investigated and demostrated to play a central role in
the transverse mode dynamics. While the idler beam can oscillate in a
Laguerre-Gauss mode, the crystal birefringence induces an astigmatic effect in
the signal beam that prevents the resonance of such mode.


title:
Apparent slip due to the motion of suspended particles in flows of
  electrolyte solutions

abstract:
  We consider pressure-driven flows of electrolyte solutions in small channels
or capillaries in which tracer particles are used to probe velocity profiles.
Under the assumption that the double layer is thin compared to the channel
dimensions, we show that the flow-induced streaming electric field can create
an apparent slip velocity for the motion of the particles, even if the flow
velocity still satisfies the no-slip boundary condition. In this case, tracking
of particle would lead to the wrong conclusion that the no-slip boundary
condition is violated. We evaluate the apparent slip length, compare with
experiments, and discuss the implications of these results.


title:
A Unity of Science, Especially Among Physicists, Is Urgently Needed to
  End Medicine's Lethal Misdirection

abstract:
  We have all read that: (1) organized medicine was laughing at the germ theory
and refused to wash its hands in the late 1800's while women died of childbed
fever and other patients of wound sepsis (scientists in general, including
physicists, were among those who died); and (2) during the 1900's, and still
today, organized medicine is laughing at the essential nutrient theory. We now
hear the medical quality assurance boards enforce MANY MISTAKEN VIEWS and DO
NOT recognize that: "xenobiotics can't be substituted for essential nutrients;
ascorbic acid is NOT a vitamin and hence, is needed in multi-gram (not minute
amounts) for optimum health; there is great harm in a diet deriving half its
calories from refined carbohydrates as is common in the US today; dietary
correction is possible at a stage when surgery is contemplated for a cardiac
patient; mercury dental fillings and even the high-copper variety most widely
used are extremely unsafe;" etc. The purpose of this manuscript is to elicit
coordinated collective effort of physicists, other scientists and the Union of
Concerned Scientists to educate the public and end this tyranny of organized
medicine whose methods are reported to cause much M&M (over a million
unnecessary US deaths at a cost of many billion dollars annually). The
biochemistry of these errors would be trivial to understand for physicists and
other scientists (who are all still going innocently to slaughter among those
dying needlessly, even today).


title: Summary Of Working Group On Single Beam High Luminosity Issues

abstract:
  The aim of the Working Group on Single Beam Behaviour was to concentrate on
the items limiting the achievement of high luminosity. Some are related to high
current and short bunch distance, as electron cloud instability (ECI), the
others to the lattice design, as Dynamic Aperture (DA), wigglers, Interaction
Region (IR) design, lifetime and background. These arguments have been
discussed to explore the feasibility of a very high luminosity Phi-factory.


title:
Dependence of the transition from Townsend to glow discharge on
  secondary emission

abstract:
  In a recent paper Sijacic and Ebert have systematically studied the
transition from Townsend to glow discharge, refering to older work from von
Engel (1934) up to Raizer (1991), and they stated a strong dependendence on
secondary emission $\gamma$ from the cathode. We here show that the earlier
results of von Engel and Raizer on the small current expansion about the
Townsend limit actually are the limit of small $\gamma$ of the new expression;
and that for larger $\gamma$ the old and the new results vary by no more than a
factor of 2. We discuss the $\gamma$-dependence of the transition which is
rather strong for short gaps.


title: Possible Observation of a Second Kind of Light - Magnetic Photon Rays

abstract:
  Several years ago, I suggested a quantum field theory which has many
attractive features. (1) It can explain the quantization of electric charge.
(2) It describes symmetrized Maxwell equations. (3) It is manifestly covariant.
(4) It describes local four-potentials. (5) It avoids the unphysical Dirac
string. My model predicts a second kind of light, which I named ``magnetic
photon rays.'' Here I will discuss possible observations of this radiation by
August Kundt in 1885, Alipasha Vaziri in February 2002, and Roderic Lakes in
June 2002.


title: Dashen-Frautschi Fiasco and Historical Roadmap for Strings

abstract:
  In 1964, Dashen and Frautschi published two papers in the Physical Review
claiming that they calculated the neutron-proton mass difference. It was once
regarded as a history-making calculation, in view of the fact that the proton
and neutron had been and still are regarded as the same particle with different
electromagnetic properties. However, their calculation was shown to be based on
a bound-state wave function which violates the localization condition in
quantum mechanics.
  There is one important lesson to be learned from the mistake made by Dashen
and Frautschi. They did not pay much attention to the fact that there are
running waves and standing waves in quantum mechanics. The S-matrix formalism
is based on running waves, while bound-state problem are based on normalizable
wave functions which are standing waves. Wave functions contained in the S
matrix are analytic continuations of running waves, and they do not in general
satisfy the localization condition for bound states.
  These days, there are very serious questions raised against string theory. Is
string theory a form of quantum field theory? Is it a physical theory or only a
mathematical exercise. Is a new new Einstein going to emerge from string
theory? It is pointed out that, if the distinction is recognized between
running and standing waves, string theory has its place in the historical
roadmap land-marked by Einstein, Heisenberg, Schr\"odinger, Dirac, Wigner, and
Feynman.


title:
An Application of Transfer Hamiltonian Quantum Mechanics to Multi-Scale
  Modeling

abstract:
  In quantum/classical (QM/CM) partitioning methods for multi-scale modeling,
one is often forced to introduce uncontrolled phenomenological effects of the
environment (CM) in the quantum (QM) domain as ab initio quantum calculations
are computationally too intensive to be applied to the whole sample. We propose
a method, in which two qualitatively different components of the information
about the state of the CM region are incorporated into the QM calculations.
First, pseudoatoms constructed to describe the chemistry of the nearest
neighbor exchange interactions replace the atoms at the boundary of the CM and
the QM regions. Second, the remaining effect of the CM bulk environment due to
long-range Coulombic interactions is modeled in terms of dipoles. We have
tested this partitioning method in a silica nanorod and a 3-membered silica
ring for which ab initio quantum data for the whole system is available to
assess the quality of the proposed partitioning method.


title:
Precision measurements of timing characteristics of the 8" ETL9351
  series photomultiplier

abstract:
  During the test measurements of the PMTs to be used in the future Borexino
experiment, the data from 2200 PMT were accumulated. The unique timing
characteristics of the apparatus used and the large statistics acquired, permit
resololution of the fine structure of the ETL9351 PMT time response.
  A method to obtain the probability density function of the single
photoelectron counting from the experimental data is proposed and applied to
derive the PMT average characteristics. For the first time, an analytical model
of the single photoelectron PMT time response is proposed, describing all the
features of the single photoelectron time arrival. The origin of the small
amplitude pulses is explained.


title:
On the possiblity of detecting Solar pp-neutrino with a large volume
  liquid organic scintillator detector

abstract:
  It is shown that a large volume liquid organic scintillator detector with an
energy resolution of 10 keV at 200 keV 1 sigma will be sensitive to solar
pp-neutrino, if operated at the target radiopurity levels for the Borexino
detector, or the solar neutrino project of KamLAND.


title: Deriving laws from ordering relations

abstract:
  The effect of Richard T. Cox's contribution to probability theory was to
generalize Boolean implication among logical statements to degrees of
implication, which are manipulated using rules derived from consistency with
Boolean algebra. These rules are known as the sum rule, the product rule and
Bayes' Theorem, and the measure resulting from this generalization is
probability. In this paper, I will describe how Cox's technique can be further
generalized to include other algebras and hence other problems in science and
mathematics. The result is a methodology that can be used to generalize an
algebra to a calculus by relying on consistency with order theory to derive the
laws of the calculus. My goals are to clear up the mysteries as to why the same
basic structure found in probability theory appears in other contexts, to
better understand the foundations of probability theory, and to extend these
ideas to other areas by developing new mathematics and new physics. The
relevance of this methodology will be demonstrated using examples from
probability theory, number theory, geometry, information theory, and quantum
mechanics.


title: Observation of optical spatial solitons in a highly nonlocal medium

abstract:
  We report on the observation and quantitative assessment of self-trapped
pulsating beams in a highly non-local nonlinear regime. The experiments were
conducted in nematic liquid crystals and allow a meaningful comparison with the
prediction of a scalar theory in the perturbative limit, while addressing the
need for beyond-paraxial analytical treatments.


title: Linear algebra of reduced units and discussion of temperature parameter

abstract:
  A formal linear vector field representation for scientific equations is
developed to rationalize the intuitive methods that are constantly employed. It
is shown that unlike mechanical units that appear in the basis of the space,
the reduced temperature and Boltzmann parameter cannot be described by the
basis set individually and can only be described as a product. Further, the
definition and determination of temperature is dependent on theory and not on
standard mechanical units. It is shown that there is no reason to reduce the
number of degrees of freedom in temperature determination via equipartition
since stochastic variables are involved, and this observation is significant in
that the temperature variable reported in simulation studies would have a
discrepancy to the extent of using the decreased number of freedom, which is
most cases is not large nor significant. The standard assignments used in
reduced units do not lead to errors because operationally the resulting reduced
temperature parameter represents the reduced product of the temperature and
Boltzmann parameters. The non-independence of these quantities explains why
entropy and other associated functions cannot be calculated directly, but are
always scaled in dimensionless increments of the Boltzmann parameter.


title: A Gauge Like Formulation of Gravitation and Related Issues

abstract:
  After many fruitless decades of trying to unify electromagnetism and
gravitation, it is now being realized that this can be done only in discrete
spacetime, as indeed the author had demonstrated. In this context, a unified
description of gravitation and electromagnetism is provided within the
framework of a gauge like formulation. Following the discrete spacetime
structure, we then argue that the underpinning for the universe is an array of
Planck scale oscillators.


title:
Parametric instability of linear oscillators with colored time-dependent
  noise

abstract:
  The goal of this paper is to discuss the link between the quantum phenomenon
of Anderson localization on the one hand, and the parametric instability of
classical linear oscillators with stochastic frequency on the other. We show
that these two problems are closely related to each other. On the base of
analytical and numerical results we predict under which conditions colored
parametric noise suppresses the instability of linear oscillators.

categories: physics.class-ph cond-mat.dis-nn math-ph math.MP physics.comp-ph quant-ph


title:
Magneto-electro-optical properties of the quantum vacuum and Lorentz
  invariance

abstract:
  We consider the magneto-electric optical properties of the quantum vacuum and
show that all the different phenomenona are related by Lorentz invariance. As a
model calculation we show how crossed fields properties can be calculated
starting from single field properties by using Lorentz transformations. Using
this method we have studied for the first time the case of a crossed static
magnetic field and electric field applied with one of these two fields parallel
to the direction of light propagation. We also show that parallel field
properties can be found using general symmetry properties.


title:
Luminosity, Energy and Polarization Studies for the Linear Collider:
  Comparing e+e- and e-e- for NLC and TESLA

abstract:
  We present results from luminosity, energy and polarization studies at a
future Linear Collider. We compare e+e- and e-e- modes of operation and
consider both NLC and TESLA beam parameter specifications at a center-of-mass
energy of 500 GeV. Realistic colliding beam distributions are used, which
include dynamic effects of the beam transport from the Damping Rings to the
Interaction Point. Beam-beam deflections scans and their impact for beam-based
feedbacks are considered. A transverse kink instability is studied, including
its impact on determining the luminosity-weighted center-of-mass energy.
Polarimetry in the extraction line from the IP is presented, including results
on beam distributions at the Compton IP and at the Compton detector.


title:
Phase Synchronization and Polarization Ordering of Globally-Coupled
  Oscillators

abstract:
  We introduce a prototype model for globally-coupled oscillators in which each
element is given an oscillation frequency and a preferential oscillation
direction (polarization), both randomly distributed. We found two collective
transitions: to phase synchronization and to polarization ordering. Introducing
a global-phase and a polarization order parameters, we show that the transition
to global-phase synchrony is found when the coupling overcomes a critical value
and that polarization order enhancement can not take place before global-phase
synchrony. We develop a self-consistent theory to determine both order
parameters in good agreement with numerical results.


title:
Non-diffusive transport in plasma turbulence: a fractional diffusion
  approach

abstract:
  Numerical evidence of non-diffusive transport in three-dimensional, resistive
pressure-gradient-driven plasma turbulence is presented. It is shown that the
probability density function (pdf) of test particles' radial displacements is
strongly non-Gaussian and exhibits algebraic decaying tails. To model these
results we propose a macroscopic transport model for the pdf based on the use
of fractional derivatives in space and time, that incorporate in a unified way
space-time non-locality (non-Fickian transport), non-Gaussianity, and
non-diffusive scaling. The fractional diffusion model reproduces the shape, and
space-time scaling of the non-Gaussian pdf of turbulent transport calculations.
The model also reproduces the observed super-diffusive scaling.


title: Molecular Dynamics Simulation of Amyloid Beta Dimer Formation

abstract:
  Recent experiments with amyloid-beta (Abeta) peptide suggest that formation
of toxic oligomers may be an important contribution to the onset of Alzheimer's
disease. The toxicity of Abeta oligomers depends on their structure, which is
governed by assembly dynamics. Due to limitations of current experimental
techniques, a detailed knowledge of oligomer structure at the atomic level is
missing. We introduce a molecular dynamics approach to study Abeta dimer
formation: (1) we use discrete molecular dynamics simulations of a
coarse-grained model to identify a variety of dimer conformations, and (2) we
employ all-atom molecular mechanics simulations to estimate the thermodynamic
stability of all dimer conformations. Our simulations of a coarse-grained Abeta
peptide model predicts ten different planar beta-strand dimer conformations. We
then estimate the free energies of all dimer conformations in all-atom
molecular mechanics simulations with explicit water. We compare the free
energies of Abeta(1-42) and Abeta(1-40) dimers. We find that (a) all dimer
conformations have higher free energies compared to their corresponding
monomeric states, and (b) the free energy difference between the Abeta(1-42)
and the analogous Abeta(1-40) dimer conformation is not significant. Our
results suggest that Abeta oligomerization is not accompanied by the formation
of stable planar beta-strand Abeta dimers.


title:
The influence of scattered photons on the accurate determination of
  microcalcification thickness in digital mammography

abstract:
  Our interest has been to study the effect that scattered radiation has on
contrast, signal-to-noise ratio and thickness reconstruction in digital
mammographies. Using the GEANT code we have performed Monte-Carlo simulations
of 25 kVp Mo/Mo photons, through a breast phantom which contains a 0.2-1.0 mm
thick microcalcifications incident on a 20x106 $mm^{2}$ pixelized detector. The
data have been analyzed assuming 6 different shapes of the incident beam: a
0.2x0.2 $mm^{2}$ ``narrow'' beam, 4 different 20 mm long scanning beams of
various widths, and a 20x100 $mm^{2}$ beam with no scatter reduction mechanisms
(NSR) . Since the image of a point depends on scattered photons which passed up
to 2 cm away from the object (for 4 cm thick phantom), we identify the
background definition as a main source of systematic uncertainty in the image
quality analysis. We propose the use of two dimensional functions (a polynomial
for the background and Gaussians for the signal) for total photon transmission
description. Our main results indicate the possible calcification thickness
reconstruction with an accuracy of the order of 6% using 3 mm wide scanning
beam. Signal-to-noise ratio with the 3 mm wide beam gets improved by 20% with
respect to NSR, a figure similar to that obtained with the narrow beam.
Thickness reconstruction is shown to be an alternative to signal-to-noise ratio
for microcalcification detection.


title: On the genesis of Post constraint in modern electromagnetism

abstract:
  The genesis of the Post constraint is premised on two attributes of modern
electromagnetism: (i) its microscopic nature, and (ii) the status of e and b as
the primitive electromagnetic fields. This constraint can therefore not arise
in EH--electromagnetism, wherein the primitive electromagnetic fields are the
macroscopic fields E and H.


title: Polarization maintaining large mode area photonic crystal fiber

abstract:
  We report on a polarization maintaining large mode area photonic crystal
fiber. Unlike, previous work on polarization maintaining photonic crystal
fibers, birefringence is introduced using stress applying parts. This has
allowed us to realize fibers, which are both single mode at any wavelength and
have a practically constant birefringence for any wavelength. The fibers
presented in this work have mode field diameters from about 4 to 6.5 micron,
and exhibit a typical birefringence of 1.5e-4.


title: Energy Ramping for DAFNE-2

abstract:
  The aim of this paper is to overview the energy ramping main issues for
DAFNE-2, the high-energy upgrade of the Frascati e+e- DAFNE collider in order
to understand the feasibility of the process itself and to define the tools to
be developed for its implementation.


title: Surface Superconductivity in Niobium for Superconducting RF Cavities

abstract:
  A systematic study is presented on the superconductivity (sc) parameters of
the ultrapure niobium used for the fabrication of the nine-cell 1.3 GHz
cavities for the linear collider project TESLA. Cylindrical Nb samples have
been subjected to the same surface treatments that are applied to the TESLA
cavities: buffered chemical polishing (BCP), electrolytic polishing (EP),
low-temperature bakeout (LTB). The magnetization curves and the complex
magnetic susceptibility have been measured over a wide range of temperatures
and dc magnetic fields, and also for di erent frequencies of the applied ac
magnetic field. The bulk superconductivity parameters such as the critical
temperature Tc = 9.26 K and the upper critical field Bc2(0) = 410 mT are found
to be in good agreement with previous data. Evidence for surface
superconductivity at fields above Bc2 is found in all samples. The critical
surface field exceeds the Ginzburg-Landau field Bc3 = 1.695Bc2 by about 10% in
BCP-treated samples and increases even further if EP or LTB are applied. From
the field dependence of the susceptibility and a power-law analysis of the
complex ac conductivity and resistivity the existence of two different phases
of surface superconductivity can be established which resemble the Meissner and
Abrikosov phases in the bulk: (1) coherent surface superconductivity, allowing
sc shielding currents flowing around the entire cylindrical sample, for
external fields B in the range between Bc2 and Bcohc3, and (2) incoherent
surface superconductivity with disconnected sc domains between Bcohc3 and Bc3.
The coherent critical surface field separating the two phases is found to be
Bcoh c3 = 0.81Bc3 for all samples. The exponents in the power law analysis are
different for BCP and EP samples, pointing to different surface topologies.


title: A note on Delta ln L = -1/2 Errors

abstract:
  The points at which the log likelihood falls by 1/2 from its maximum value
are often used to give the `errors' on a result, i.e. the 68% central
confidence interval. The validity of this is examined for two simple cases: a
lifetime measurement and a Poisson measurement. Results are compared with the
exact Neyman construction and with the simple Bartlett approximation. It is
shown that the accuracy of the log likelihood method is poor, and the Bartlett
construction explains why it is flawed.


title: Driven cavity flow: from molecular dynamics to continuum hydrodynamics

abstract:
  Molecular dynamics (MD) simulations have been carried out to investigate the
slip of fluid in the lid driven cavity flow where the no-slip boundary
condition causes unphysical stress divergence. The MD results not only show the
existence of fluid slip but also verify the validity of the Navier slip
boundary condition. To better understand the fluid slip in this problem, a
continuum hydrodynamic model has been formulated based upon the MD verification
of the Navier boundary condition and the Newtonian stress. Our model has no
adjustable parameter because all the material parameters (density, viscosity,
and slip length) are directly determined from MD simulations. Steady-state
velocity fields from continuum calculations are in quantitative agreement with
those from MD simulations, from the molecular-scale structure to the global
flow. The main discovery is as follows. In the immediate vicinity of the
corners where moving and fixed solid surfaces intersect, there is a core
partial-slip region where the slippage is large at the moving solid surface and
decays away from the intersection quickly. In particular, the structure of this
core region is nearly independent of the system size. On the other hand, for
sufficiently large system, an additional partial-slip region appears where the
slippage varies as $1/r$ with $r$ denoting the distance from the corner along
the moving solid surface. The existence of this wide power-law region is in
accordance with the asymptotic $1/r$ variation of stress and the Navier
boundary condition.


title: Composition-induced structural transitions in mixed rare-gas clusters

abstract:
  The low-energy structures of mixed Ar--Xe and Kr--Xe Lennard-Jones clusters
are investigated using a newly developed parallel Monte Carlo minimization
algorithm with specific exchange moves between particles or trajectories. Tests
on the 13- and 19- atom clusters show a significant improvement over the
conventional basin-hopping method, the average search length being reduced by
more than one order of magnitude. The method is applied to the more difficult
case of the 38-atom cluster, for which the homogeneous clusters have a
truncated octahedral shape. It is found that alloys of dissimilar elements
(Ar--Xe) favor polytetrahedral geometries over octahedra due to the reduced
strain penalty. Conversely, octahedra are even more stable in Kr--Xe alloys
than in Kr_38 or Xe_38, and they show a core-surface phase separation behavior.
These trends are indeed also observed and further analysed on the 55-atom
cluster. Finally, we correlate the relative stability of cubic structures in
these clusters to the glassforming character of the bulk mixtures.


title: The Bowl Championship Series: A Mathematical Review

abstract:
  We discuss individual components of the college football Bowl Championship
Series, compare with a simple algorithm defined by random walks on a biased
graph, attempt to predict whether the proposed changes will truly lead to
increased BCS bowl access for non-BCS schools, and conclude by arguing that the
true problem with the BCS Standings lies not in the computer algorithms, but
rather in misguided addition.


title: On Temperature Radiation

abstract:
  In this work we compare two blackbody interpretations, those of G. Kirchhoff
and M. Planck. We separate the problem of interpreting the blackbody spectrum
from that of determining the mechanical equivalent of radiation. Then we
propose that, if we set aside characterization of the blackbody,
electromagnetism suffices to analyze spectral distribution and leads to
interpreting it as determined by the receiver band-pass.


title:
A Proposed Interpretation of Microwave Ionization of Rydberg Alkali
  Atoms

abstract:
  I show that the theory developed for quantum delocalization of an excited
Hydrogen atom in a two-frequency linearly polarized microwave field can be used
with a few adaptions to explain the quantum delocalization of Alkali atoms in a
linearly polarized monochromatic field in the regime where it deviates from
Hydrogenic behaviour. Comparison with numerical and laboratory experiments is
satisfactory: apart from a constant factor, independent from the microwave
frequency, the same dependence from the initial quantum number is observed.


title: Spectroscopic Interpretation: The High Vibrations of CDBrClF

abstract:
  We extract the dynamics implicit in an algebraic fitted model Hamiltonian for
the deuterium chromophore's vibrational motion in the molecule CDBrClF. The
original model has 4 degrees of freedom, three positions and one representing
interbond couplings. A conserved polyad allows in a semiclassical approach the
reduction to 3 degrees of freedom. For most quantum states we can identify the
underlying motion that when quantized gives the said state. Most of the
classifications, identifications and assignments are done by visual inspection
of the already available wave function semiclassically transformed from the
number representation to a representation on the reduced dimension toroidal
configuration space corresponding to the classical action and angle variables.
The concentration of the wave function density to lower dimensional subsets
centered on idealized simple lower dimensional organizing structures and the
behavior of the phase along such organizing centers already reveals the atomic
motion. Extremely little computational work is needed.


title:
Analysis of an algebraic model for the chromophore vibrations of
  CF$_3$CHFI

abstract:
  We extract the dynamics implicit in an algebraic fitted model Hamiltonian for
the hydrogen chromophore's vibrational motion in the molecule $CF_3CHFI$. The
original model has 4 degrees of freedom, three positions and one representing
interbond couplings. A conserved polyad allows the reduction to 3 degrees of
freedom. For most quantum states we can identify the underlying motion that
when quantized gives the said state. Most of the classifications,
identifications and assignments are done by visual inspection of the already
available wave function semiclassically transformed from the number
representation to a representation on the reduced dimension toroidal
configuration space corresponding to the classical action and angle variables.
The concentration of the wave function density to lower dimensional subsets
centered on idealized simple lower dimensional organizing structures and the
behavior of the phase along such organizing centers already reveals the atomic
motion. Extremely little computational work is needed.


title: The impact of field shape optimization: A feasibility study

abstract:
  The impact of field shape optimization is studied for prostate type geometry.
For this study, 76 and 81 Gy plans were generated. Dose distributions for
wedged plans and Intensity Modulated (IM) plans for three and seven fields were
compared for a quadratic cost function. For wedged plans, a Simulated Annealing
Algorithm (SAA) was used to optimize gantry angles, wedge angles, beam weights
and field shapes. Two kinds of wedged plans were generated: 1) field sizes were
determined by the requirement of full target coverage in the beam's-eye-view
(fixed fields) and 2) the field shape, in particular at the critical organ
target overlap region was also among the variables optimized. For IM plans the
SAA was used to optimize gantry angles and a conjugate gradient algorithm was
used to optimize the IM beam fluences. Both the field shape optimized wedged
plans and IM plans had significantly superior dose area histograms of the
target, rectum and the bladder and cost function values compared to the fixed
field optimized wedged plans.


title: Radiation Damage and Long-Term Aging in Gas Detectors

abstract:
  Aging phenomena constitute one of the most complex and serious potential
problems which could limit, or severely impair, the use of gaseous detectors in
unprecedented harsh radiation environments. Long-term operation in
high-intensity experiments of the LHC-era not only demands extraordinary
radiation hardness of construction materials and gas mixtures but also very
specific and appropriate assembly procedures and quality checks during detector
construction and testing. Recent experimental data from hadron beams is
discussed. It is shown that the initial stage of radiation tests, usually
performed under isolated laboratory conditions, may not offer the full
information needed to extrapolate to the long-term performance of real and
full-size detectors at high energy physics facilities. Major factors, closely
related to the capability of operating at large localized ionization densities,
and which could lead to operation instabilities and subsequent aging phenomena
in gaseous detectors, are summarized. Finally, an overview of aging experience
with state-of-the-art gas detectors in experiments with low- and high-intensity
radiation environments is given with a goal of providing a set of rules, along
with some caveat, for the construction and operation of gaseous detectors in
high luminosity experiments.


title: A brief history of drop formation

abstract:
  Surface-tension-related phenomena have fascinated researchers for a long
time, and the mathematical description pioneered by Young and Laplace opened
the door to their systematic study. The time scale on which
surface-tension-driven motion takes place is usually quite short, making
experimental investigation quite demanding. Accordingly, most theoretical and
experimental work has focused on static phenomena, and in particular the
measurement of surface tension, by physicists like E\"otv\"os, Lenard, and
Bohr. Here we will review some of the work that has eventually lead to a closer
scrutiny of time-dependent flows, highly non-linear in nature. Often this
motion is self-similar in nature, such that it can in fact be mapped onto a
pseudo-stationary problem, amenable to mathematical analysis.


title: Measuring the force ejecting DNA from phage

abstract:
  We discuss how a balance can be established between the force acting to eject
DNA from viral capsids and the force resisting its entry into a colloidal
suspension which mimics the host cell cytoplasm. The ejection force arises from
the energy stored in the capsid as a consequence of the viral genome
(double-stranded DNA) being strongly bent and crowded on itself. The resisting
force is associated with the osmotic pressure exerted by the colloidal
particles in the host solution. Indeed, recent experimental work has
demonstrated that the extent of ejection can be progressively limited by
increasing the external osmotic pressure; at a sufficiently high pressure the
ejection is completely suppressed. We outline here a theoritical analysis that
allows a determination of the internal (capsid) pressure by examining the
different relations between force and pressure inside and outside the capsid,
using the experimentally measured position of the force balance.


abstract:
  The paper formulates Maxwell's equations in 4-dimensional Euclidean space by
embedding the electromagnetic vector potential in the frame vector $g_0$.
Relativistic electrodynamics is the first problem tackled; in spite of using a
geometry radically different from that of special relativity, the paper derives
relativistic electrodynamics from space curvature. Maxwell's equations are then
formulated and solved for free space providing solutions which rotate the
vector potential on a plane; these solutions are shown equivalent to the usual
spacetime formulation and are then discussed in terms of the hypersphere model
of the Universe recently proposed by the author.


title: Limits and Confidence Intervals in the Presence of Nuisance Parameters

abstract:
  We study the frequentist properties of confidence intervals computed by the
method known to statisticians as the Profile Likelihood. It is seen that the
coverage of these intervals is surprisingly good over a wide range of possible
parameter values for important classes of problems, in particular whenever
there are additional nuisance parameters with statistical or systematic errors.
Programs are available for calculating these intervals.


title:
Silicon clusters produced by femtosecond laser ablation: Non-thermal
  emission and gas-phase condensation

abstract:
  Neutral silicon clusters Si_n (up to n = 7) and their cations Si_n+ (up to n
= 10) have been produced by femtosecond laser ablation of bulk silicon in
vacuum and investigated using time-of-flight mass spectrometry. Two populations
of the Si_n+ clusters with different velocity and abundance distributions in
the ablation plume have been clearly distinguished. Possible mechanisms of
cluster formation (Coulomb explosion, gas-phase condensation, phase explosion)
are discussed.


title:
Ocean's Skeletal Structures, Hypotheses and Interpretation of the
  Phenomenon

abstract:
  An analysis of databases of photographic images of ocean's surface, taken
from various altitudes and for various types of rough ocean surface, revealed
the presence of an ocean's skeletal structures (OSS). The OSSs differ from the
formerly found skeletal structures (SS) only by the fact that OSS, in their
interior, are filled in with closely packed blocks of a smaller size, up to
thin capillaries of tens of micron in size. According to suggested hypothesis,
the structure-forming dust is produced due to volcanic activity and atmospheric
electricity. Such SS may fall on the ocean surface and produce an OSS. This
idea is supported by the adsorption of air bubbles in the water by the SS to
give a partial flotation of SS. In the sea water, various substances in
different phase states of matter are in touch. This suggests the hypothesis,
for the possibility of the action of surface tension even on the blocks of SS
which is immersed in the sea. This phenomenon results in the aggregation of
blocks deposited from the atmosphere on the ocean's surface, to form eventually
an OSS. The skeletal structuring assumes that the individual straight and
rather strong blocks may be joined flexibly, similarly to joints in a skeleton.
We make a stress on the phenomenon of OSS's blocks in the form of vertically
oriented floating cylinders because here we suggest the hypothesis that the
VFC's strength and floating is determined by; a capillary model of an OSS.