title: On Aryabhata's Planetary Constants

abstract:
  This paper examines the theory of a Babylonian origin of Aryabhata's
planetary constants. It shows that Aryabhata's basic constant is closer to the
Indian counterpart than to the Babylonian one. Sketching connections between
Aryabhata's framework and earlier Indic astronomical ideas on yugas and cyclic
calendar systems, it is argued that Aryabhata's system is an outgrowth of an
earlier Indic tradition.


title:
Trapping, Compression and Acceleration of an Electron Bunch in the
  Nonlinear Laser Wakefield

abstract:
  A scheme of laser wakefield acceleration, when a relatively rare and long
bunch of non-relativistic or weakly-relativistic electrons is initially in
front of the laser pulse, is suggested and considered. The motion of test
electrons is studied both in the one-dimensional case (1D wakefield) and in the
three-dimensional laser wakefield excited in a plasma channel. It is shown that
the bunch is trapped, effectively compressed both in longitudinal and
transverse directions and accelerated to ultra-relativistic energies in the
region of first accelerating maximum of the wakefield. The accelerated bunch
has sizes much less than the plasma wavelength and relatively small energy
spread.


title: Galileo's Discovery of Scaling Laws

abstract:
  Galileo's realization that nature is not scale invariant, motivating his
subsequent discovery of scaling laws, is traced to two lectures he gave on the
geography of Dante's Inferno.


title:
Application of density functional theory to line broadening: Cs atoms in
  liquid helium

abstract:
  We test the applicability of density functional theory (DFT) to spectral
perturbations taking an example of a Cs atom surrounded by superfluid helium.
The atomic DFT of helium is used to obtain the distribution of helium atoms
around the impurity atom, and the electronic DFT is applied to the excitations
of the atom, averaging over the ensemble of helium configurations. The shift
and broadening of the D1 and D2 absorption lines are quite well reproduced by
theory, suggesting that the DFT may be useful for describing spectral
perturbations in more complex environments.


title: Electron trajectory in the hydrogen atom

abstract:
  A trajectory in the Schroedinger wave for an electron in an attractive
Coulomb potential with the dynamical behavior is proposed and illustrated for a
scattering and a bound state. The scattering cross section derived from the
trajectories is almost exactly equal to that from the usual wave theory. The
statistical nature of the result is examined. The period of one cycle in the
bound state is exactly equal to that of the corresponding classical motion.


title: Some Analytical Results on Classical Tunneling of Sommerfeld Particle

abstract:
  A simple example of especially constructed potential barrier enables to show
analytically (not numerically) the existence of tunneling effect for a
Sommerfeld particle.


title:
Annihilation rate in positronic systems by quantum Monte Carlo. e$^+$LiH
  as test case

abstract:
  An accurate method to compute the annihilation rate in positronic systems by
means of quantum Monte Carlo simulations is tested and compared with previously
proposed methods using simple model systems. This method can be applied within
all the quantum Monte Carlo techniques, just requiring to accumulate the
positron-electron distribution function. The annihilation rate of e$^+$LiH as a
function of the internuclear distance is studied using a model potential
approach to eliminate the core electrons of Li, and explicitly correlated wave
functions to deal with all the remaining particles. These results allow us to
compute vibrationally averaged annihilation rates, and to understand the effect
of the Li$^+$ electric field on positron and electron distributions.


title:
On the Relationship Between Proximal and Distal Stimuli and an Example
  of Its Significance to Physics

abstract:
  The difference between proximal and distal stimuli is discussed and an
example of the significance of this difference to physics is pointed out in the
area of quantum teleportation. In particular, experimental evidence concerning
the relative status of the distal stimulus to the observer points toward the
relative nature of spatial orientation of objects. In quantum teleportation,
this result indicates that the amount of classical information that needs to be
transmitted to support the quantum transfer of information may be greater than
is expected when the distal stimulus is assumed, as it ordinarily is, to have
an absolute orientation in relation to the observer.


title:
Coordinated Slowing of Metabolism in Enteric Bacteria under Nitrogen
  Limitation: A Perspective

abstract:
  It is natural to ask how bacteria coordinate metabolism when depletion of an
essential nutrient limits their growth, and they must slow their entire rate of
biosynthesis. A major nutrient with a fluctuating abundance is nitrogen. The
growth rate of enteric bacteria under nitrogen-limiting conditions is known to
correlate with the internal concentration of free glutamine, the glutamine
pool. Here we compare the patterns of utilization of L-glutamine and
L-glutamate, the two central intermediates of nitrogen metabolism. Monomeric
precursors of all of the cell's macromolecules -- proteins, nucleic acids, and
surface polymers -- require the amide group of glutamine at the first dedicated
step of biosynthesis. This is the case even though only a minority (~12%) of
total cell nitrogen derives from glutamine. In contrast, the amino group of
glutamate, which provides the remainder of cell nitrogen, is generally required
late in biosynthetic pathways, e.g. in transaminase reactions for amino acid
synthesis. We propose that the pattern of glutamine dependence coordinates the
decrease in biosynthesis under conditions of nitrogen limitation. Hence, the
glutamine pool plays a global regulatory role in the cell.


title: Fundamental Radar Properties: Hidden Variables in Spacetime

abstract:
  A derivation of the properties of pulsed radiative imaging systems is
presented with examples drawn from conventional, synthetic aperture, and
interferometric radar. A geometric construction of the space and time
components of a radar observation yields a simple underlying structural
equivalence between many of the properties of radar, including resolution,
range ambiguity, azimuth aliasing, signal strength, speckle, layover, Doppler
shifts, obliquity and slant range resolution, finite antenna size, atmospheric
delays, and beam and pulse limited configurations. The same simple structure is
shown to account for many interferometric properties of radar - height
resolution, image decorrelation, surface velocity detection, and surface
deformation measurement. What emerges is a simple, unified description of the
complex phenomena of radar observations. The formulation comes from fundamental
physical concepts in relativistic field theory, of which the essential elements
are presented. In the terminology of physics, radar properties are projections
of hidden variables - curved worldlines from a broken symmetry in Minkowski
spacetime - onto a time-serial receiver.

categories: physics.optics astro-ph hep-th physics.gen-ph


title: Newton On Absolute Space: A Commentary

abstract:
  Newton seems to have stated a quantitative relationship between the position
of a body in relative space and the position of the body in absolute space in
the first scholium of his Principia. We show that if this suspected
relationship is assumed to hold, it will dispel many errors and
misrepresentations that have plagued Newton's ideas on absolute space since
their inauguration.


title: A Reconciliation of Electromagnetism and Gravitation

abstract:
  It is argued that once we consider the underpinning of a Non Commutative
geometry, itself symptomatic of extended particles, for example in Quantum
Superstring theory, then a reconciliation between gravitation and
electromagnetism is possible.


title: A precursor of the sciences of complexity in the XIX century

abstract:
  The sciences of complexity present some recurrent themes: the emergence of
qualitatively new behaviors in dissipative systems out of equilibrium, the
aparent tendency of complex system to lie at the border of phase transitions
and bifurcation points, a historical dynamics which present punctuated
equilibrium, a tentative of complementing Darwinian evolution with certain
ideas of progress (understood as increase of computational power) etc. Such
themes, indeed, belong to a long scientific and philosophical tradiction and,
curiously, appear already in the work of Frederick Engels at the 70's of the
XIX century. So, the apparent novelity of the sciences of complexity seems to
be not situated in its fundamental ideas, but in the use of mathematical and
computational models for illustrate, test and develop such ideas. Since
politicians as the candidate Al Gore recently declared that the sciences of
complexity have influenced strongly their worldview, perhaps it could be
interesting to know better the ideas and the ideology related to the notion of
complex adaptive systems.


title:
Gravitational Radiation and its Application to Space Travel, principles
  and required scientific developments

abstract:
  Gravitational radiation is an elusive form of radiation predicted by general
relativity, it is the subject of intense theoretical and experimental research
at the limit of the sensitivity of today's instrumentation. In spite of the
fact that no direct evidence of this radiation now exist, observed
astrophysical phenomena have given convincing proofs of its existence. Theories
predict that gravitational radiation may also be employed for propulsion,
moreover the nonlinear behaviour of spacetime may permit the generation of
spacetime singularities with colliding beams of gravitational radiation, this
phenomenon could become a form of propellantless propulsion. Both applications
would require gravitational wave generators with high power and appropriate
optical properties. Among the proposed techniques that could be applicable to
the production of gravitational waves, a promising one is the possible emission
of gravitons by quantum systems. A hypothesis describing the production of
gravitons in s-wave/d-wave superconductor junction is presented.


title: Some simple physical facts about the collapse of the Twin Towers

abstract:
  An analysis of the collapse of the Twin Towers is carried on with the aid of
simple mechanical laws. The motion of the collapse front is calculated in terms
of geometric and energetic quantities.


title: A Piece of the Lepton Theory from a Probability

abstract:
  A masses of a leptons deduced from a representation of a probability density
vector by a spinors. A massive W and Z bosons and a massless A boson are
obtained from a transformations for which a density vector is invariant.


title:
Gravity compensation in complex plasmas by application of a temperature
  gradient

abstract:
  Micron sized particles are suspended or even lifted up in a gas by
thermophoresis. This allows the study of many processes occurring in strongly
coupled complex plasmas at the kinetic level in a relatively stress-free
environment. First results are presented. The technique is also of interest for
technological applications.


title: Numerical evidence of breaking of vortex lines in an ideal fluid

abstract:
  Emergence of singularity of vorticity at a single point, not related to any
symmetry of the initial distribution, has been demonstrated numerically for the
first time. Behavior of the maximum of vorticity near the point of collapse
closely follows the dependence 1/(t0-t), where t0 is the time of collapse. This
agrees with the interpretation of collapse in an ideal incompressible fluid as
of the process of vortex lines breaking.


title: Classical electrodynamics of point charges

abstract:
  A simple mathematical procedure is introduced which allows redefining in an
exact way divergent integrals and limits that appear in the basic equations of
classical electrodynamics with point charges. In this way all divergences are
at once removed without affecting the locality and the relativistic covariance
of the theory, and with no need for mass renormalization. The procedure is
first used to obtain a finite expression for the electromagnetic
energy-momentum of the system. We show that the relativistic Lorentz-Dirac
equation can be deduced from the conservation of this electromagnetic
energy-momentum plus the usual mechanical term. Then we derive a finite
lagrangian, which depends on the particle variables and on the actual
electromagnetic potentials at a given time. From this lagrangian the equations
of motion of both particles and fields can be derived via Hamilton's
variational principle. The hamiltonian formulation of the theory can be
obtained in a straightforward way. This leads to an interesting comparison
between the resulting divergence-free expression of the hamiltonian functional
and the standard renormalization rules for perturbative quantum
electrodynamics.

categories: physics.class-ph hep-th math-ph math.MP physics.gen-ph


title: Magnetosphere-Ionosphere Coupling in the Region of Auroral Electrojets

abstract:
  We discuss the question as to how the magnetospheric energy source feeds the
ionospheric current system.
  It is shown that a consistent application and further development of Kennel's
ideas makes it possible to successfully solve the magnetosphere-ionosphere
coupling problem in regard to the formation of auroral electrojets by steady
volume currents generated in the magnetosphere by the magnetospheric MHD
generator in the case of a simple model which, nevertheless, retains the
essential features of the reality. It is concluded that the whole of the
complicated magnetospheric ''design'' only acts to redistribute, in space and
time, currents and energy fluxes which must be supplied by external sources to
feed the dissipative processes in the ionosphere.


abstract:
  A new version of the R-matrix Floquet theory for laser-assisted electron-atom
scattering is presented. The theory is non-perturbative and applicable to a
non-relativistic many-electron atom or ion in a homogeneous linearly polarized
field. It is based on the use of channel functions built from field-dressed
target states, which greatly simplifies the general formalism.


title: Self Organization of Edge and Internal Pedestals in a Sandpile

abstract:
  The temperature profiles of magnetically confined plasmas can display
distinctive longlived pedestals at the edge and internally. Here we show that
such structures can arise naturally through avalanching transport in a sandpile
model. A single control parameter that is constant across the sandpile
determines the occurrence and regularity of these effects, as well as the
entrainment of global confinement to edge pedestal dynamics. The system
dynamics indicate that the pedestals are a consequence of an inverse cascade in
real space, and that self organization is necessary for their occurrence.


title: Evidence of Levy stable process in tokamak edge turbulence

abstract:
  In an effort to understand the fundamental physics of turbulent transport of
particles and heat in a tokamak, the floating potential fluctuations in the the
scrape-off layer plasma of ohmically heated ADITYA tokamak are analysed for
self-similarity using distribution function approach. It is observed that the
distribution function of a sum of n data points converges to a Levy
distribution of scale index, alpha=1.111 for n < 40 and alpha=2.0 for larger n.
In both scaling ranges, the edge fluctuation is self-similar. This observation
is backed by several supporting evidences. The results indicate that the small
scale fluctuations transport matter and heat dominantly by convection whereas
the transport due to large scale flucuations is by a diffusive process.


title:
A Single Shot, Sub-picosecond Beam Bunch Characterization with
  Electro-optic Techniques

abstract:
  In the past decade, the bunch lengths of electrons in accelerators have
decreased dramatically to the range of a few picoseconds
\cite{Uesaka94,Trotz97}. Measurement of the length as well as the longitudinal
profile of these short bunches have been a topic of research in a number of
institutions \cite{Uesaka97,Liu97,Hutchins00}. One of the techniques uses the
electric field induced by the passage of electrons in the vicinity of a
birefringent crystal to change its optical characteristics. Well-established
electro-optic techniques can then be used to measure the temporal
characteristics of the electron bunch. In this paper we present a novel,
non-invasive, single-shot approach to improve the resolution to tens of
femtoseconds so that sub-millimeter bunch length can be measured.


title: Nonresonant effects in one- and two-photon transitions

abstract:
  We investigate nonresonant contributions to resonant Rayleigh scattering
cross sections of atoms. The problematic nonresonant contributions set a limit
to the accuracy to which atomic spectra determine energy levels. We discuss the
off-resonance effects in one-photon transitions. We also show that
off-resonance contributions for the 1S-2S two-photon transition in atomic
hydrogen are negligible at current and projected levels of experimental
accuracy. The possibility of a differential measurement for the detection of
off-resonance effects in one-photon transitions in atomic hydrogen is
discussed.


title:
Performance of the triple-GEM detector with optimized 2-D readout in
  high intensity hadron beam

abstract:
  Multiple-GEM detectors are considered to be good candidates for tracking
devices in experiments with high hadronic background. We present the results of
the triple-GEM detectors beam test in a high intensity pion beam. The detectors
had an optimized two-dimensional readout with minimized strip capacitance. Such
optimization permitted the starting point of the efficiency plateau down to a
gain of 5000. The probability of GEM discharges induced by heavily ionizing
particles has been measured as a function of gain: at a gain of 20000 it
amounts to 10^(-11) per incident particle. Such a value will ensure safe
operation of the detector in the conditions of forward region of the LHC
experiments.


title: Multi-parameter generalization of nonextensive statistical mechanics

abstract:
  We show that the stochastic interpretation of Tsallis' thermostatistics given
recently by Beck [Phys. Rev. Lett {\bf 87}, 180601 (2001)] leads naturally to a
multi-parameter generalization. The resulting class of distributions is able to
fit experimental results which cannot be reproduced within the Boltzmann's or
Tsallis' formalism.


title:
Recoil correction to the bound-electron g factor in H-like atoms to all
  orders in $\alpha Z$

abstract:
  The nuclear recoil correction to the bound-electron g factor in H-like atoms
is calculated to first order in $m/M$ and to all orders in $\alpha Z$. The
calculation is performed in the range Z=1-100. A large contribution of terms of
order $(\alpha Z)^5$ and higher is found. Even for hydrogen, the higher-order
correction exceeds the $(\alpha Z)^4$ term, while for uranium it is above the
leading $(\alpha Z)^2$ correction.


title: Electric multipole plasmons in deformed sodium clusters

abstract:
  The random-phase-approximation (RPA) method with separable residual forces
(SRPA) is proposed for the description of multipole electric oscillations of
valence electrons in deformed alkali metal clusters. Both the deformed mean
field and residual interaction are derived self-consistently from the Kohn-Sham
functional. SRPA drastically simplifies the computational effort which is
urgent if not decisive for deformed systems. The method is applied to the
description of dipole, quadrupole and octupole plasmons in deformed sodium
clusters of a moderate size. We demonstrate that, in clusters with the size
N>50, Landau damping successfully competes with deformation splitting and even
becomes decisive in forming the width and gross structure of the dipole
plasmon. Besides, the plasmon is generated by excitations from both ground
state and shape isomers. In such clusters familiar experimental estimates for
deformation splitting of dipole plasmon are useless.


title: Multiple Fiztgerald-Lorentz contractions

abstract:
  In a recent paper, Harada and Sachs suggested that the Fitzgerald-Lorentz
contraction does not refer to a physical contraction but can perhaps best be
seen as a 'currency conversion'. In the present paper, this view is inspected,
and it is found, beyond the immediate frame of the interpretation, that the
Fitzgerald-Lorentz contraction leads to a contradiction in a system of more
than two observers. A possible physical system in which this can occur is a
relativistic (ideal) gas or fluid.


title: Gravitation and Electromagnetism II

abstract:
  We show how, a non commutative underpinning for spacetime throws up mass,
spin and charge and indicate how it is possible to include QCD effects also.


title: Trialogue on the number of fundamental constants

abstract:
  This paper consists of three separate articles on the number of fundamental
dimensionful constants in physics. We started our debate in summer 1992 on the
terrace of the famous CERN cafeteria. In the summer of 2001 we returned to the
subject to find that our views still diverged and decided to explain our
current positions. LBO develops the traditional approach with three constants,
GV argues in favor of at most two (within superstring theory), while MJD
advocates zero.

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


title: Dynamic Resonance of Light in Fabry-Perot Cavities

abstract:
  The dynamics of light in Fabry-Perot cavities with varying length and input
laser frequency are analyzed and the exact condition for resonance is derived.
This dynamic resonance depends on the light transit time in the cavity and the
Doppler effect due to the mirror motions. The response of the cavity to length
variations is very different from its response to laser frequency variations.
If the frequency of these variations is equal to multiples of the cavity free
spectral range, the response to length is maximized while the response to the
laser frequency is zero. Implications of these results for the detection of
gravitational waves using kilometer-scale Fabry-Perot cavities are discussed.


title: Development of Nuclotron Magnet Power Supply Control System

abstract:
  The magnetic field control subsystem of the Nuclotron - a superferric ion
synchrotron - is described. The bending (BM), focusing (QF) and defocusing (QD)
magnets are powered by three supplies. The BMs are driven by the supply of a
6.3 kA nominal current. The QFs and QDs are connected in series and powered by
the 6 kA supply. An additional supply of 200 A for the QFs is used to keep the
reqired ratio I(QF)/I(QD). The BM magnetic field shape is set by a pulse
function generator which produceds a reference burst (Bo-train) with a 0.1 Gs
resolution. A real B-train of the bending magnet field with the same (0.1 Gs)
resolution is used for feedback loop and as reference function for QD and QF
supplies. The QD and QF trains are utilized for feedback loop in the QD and QF
supplies. The control of slow extraction system suppllies is described as well.


title:
Ionospheric effects of the solar flares as deduced from global GPS
  network data

abstract:
  Results derived from analysing the ionosphere response to faint and bright
solar flares are presented. The analysis used technology of a global detection
of ionospheric effects from solar flares as developed by the authors, on the
basis of phase measurements of the total electron content (TEC) in the
ionosphere using an international GPS network. The essence of the method is
that use is made of appropriate filtering and a coherent processing of
variations in the TEC which is determined from GPS data, simultaneously for the
entire set of visible GPS satellites at all stations used in the analysis. This
technique is useful for identifying the ionospheric response to faint solar
flares (of X-ray class C) when the variation amplitude of the TEC response to
separate line-on-sight to GPS satellite is comparable to the level of
background fluctuations. The dependence of the TEC variation response amplitude
on the flares location on the Sun is investigated.


title:
Achievable Luminosities at the THERA and LinacXLHC Based ep Colliders:
  1. Round Beams

abstract:
  Different limitations on luminosity of linac-ring type colliders coming from
beam dynamics issues are considered for the examples of the $ep$ options of the
THERA and LinacXLHC proposals. It is shown that $L=1.3\times 10^{31}$ for THERA
and $L=2.7\times 10^{32}$ for LinacXLHC can be achieved for round beams case.
Corresponding sets of parameters are given with the explanations.


title: On the Dirac Approach to Constrained Dissipative Dynamics

abstract:
  In this paper, we propose a novel algebraic and geometric description for the
dissipative dynamics. Our formulation bears some similarity to the Poisson
structure for non-dissipative systems. We develop a canonical description for
constrained dissipative systems through an extension of the Dirac brackets
concept, and we present a new formula for calculating Dirac brackets. This
formula is particularly useful in the description of dynamical systems with
many second-class constraints. After presenting the necessary formal background
we illustrate our method on several examples taken from particle dynamics,
continuum media physics and wave mechanics.

categories: physics.class-ph math-ph math.MP physics.flu-dyn physics.gen-ph


title: Newton's laws of motion in form of Riccati equation

abstract:
  We discuss two applications of Riccati equation to Newton's laws of motion.
The first one is the motion of a particle under the influence of a power law
central potential $V(r)=k r^{\epsilon}$. For zero total energy we show that the
equation of motion can be cast in the Riccati form. We briefly show here an
analogy to barotropic Friedmann-Robertson-Lemaitre cosmology where the
expansion of the universe can be also shown to obey a Riccati equation. A
second application in classical mechanics, where again the Riccati equation
appears naturally, are problems involving quadratic friction. We use methods
reminiscent to nonrelativistic supersymmetry to generalize and solve such
problems


title:
Hamming distance geometry of a protein conformational space. Application
  to the clustering of a 4 ns molecular dynamics trajectory of the HIV-1
  integrase catalytic core

abstract:
  Protein structures can be encoded into binary sequences, these are used to
define a Hamming distance in conformational space: the distance between two
different molecular conformations is the number of different bits in their
sequences. Each bit in the sequence arises from a partition of conformational
space in two halves. Thus, the information encoded in the binary sequences is
also used to characterize the regions of conformational space visited by the
system. We apply this distance and their associated geometric structures, to
the clustering and analysis of conformations sampled during a 4 ns molecular
dynamics simulation of the HIV-1 integrase catalytic core. The cluster analysis
of the simulation shows a division of the trajectory into two segments of 2.6
and 1.4 ns length, which are qualitatively different: the data points to the
fact that equilibration is only reached at the end of the first segment. Some
length of the paper is devoted to compare the Hamming distance to the r.m.s.
deviation measure. The analysis of the cases studied so far, shows that under
the same conditions the two measures behave quite differently, and that the
Hamming distance appears to be more robust than the r.m.s. deviation.


title: Effective equations for photonic-crystal waveguides and circuits

abstract:
  We suggest a novel conceptual approach for describing the properties of
waveguides and circuits in photonic crystals, based on the effective discrete
equations that include the long-range interaction effects. We demonstrate, on
the example of sharp waveguide bends, that our approach is very effective and
accurate for the study of bound states and transmission spectra of the
photonic-crystal circuits, and disclose the importance of evanescent modes in
their properties.


title: The factor 2 in fundamental physics

abstract:
  A brief history is given of the factor 2, starting in the most elementary
considerations of geometry and kinematics of uniform acceleration, and moving
to relativity, quantum mechanics and particle physics. The basic argument is
that in all the significant cases in which the factor 2 or 1/2 occurs in
fundamental physics, whether classical, quantum or relativistic, the same
physical operation is taking place.


title:
Turbulent Drag Reduction of polyelectrolyte (DNA) solutions: relation
  with the elongational viscosity

abstract:
  We report measurements of turbulent drag reduction of two different
polyelectrolyte solutions: DNA and hydrolyzed Polyacrylamide. Changing the salt
concentration in the solutions allows us to change the flexibility of the
polymer chains. For both polymers the amount of drag reduction was found to
increase with the flexibility. Rheological studies reveal that the elongational
viscosity of the solutions increases simultaneously. Hence we conclude that the
elongational viscosity is the pertinent macroscopic quantity to describe the
ability of a polymer to cause turbulent drag reduction.


title: The LIGO Suspended Optic Digital Control System

abstract:
  The original LIGO suspension control system [1] used analog circuitry to
implement the closed loop damping required for local control of each the
suspended optics. Recent developments in analog to digital converters (ADC),
digital to analog converters (DAC), increased processor speed and performance,
and the use of reflective memory have made a digital alternative possible. Such
a control system would provide additional performance and flexibility that will
be required for operation of the interferometers. This paper will describe the
real-time digital servo control systems that have been designed, developed and
implemented for the LIGO suspended optics. In addition, the paper will describe
how the suspension controls have been integrated into the overall LIGO control
and data acquisition systems [2].


title: Can optical spectroscopy directly elucidate the ground state of C20?

abstract:
  The optical response of the lowest energy members of the C20 family is
calculated using time-dependent density functional theory within a real-space,
real-time scheme. Significant differences are found among the spectra of the
different isomers, and thus we propose optical spectroscopy as a tool for
experimental investigation of the structure of these important clusters.


title: On the miscible Rayleigh-Taylor instability: two and three dimensions

abstract:
  We investigate the miscible Rayleigh-Taylor (RT) instability in both 2 and 3
dimensions using direct numerical simulations, where the working fluid is
assumed incompressible under the Boussinesq approximation. We first consider
the case of randomly perturbed interfaces. With a variety of diagnostics, we
develop a physical picture for the detailed temporal development of the mixed
layer: We identify three distinct evolutionary phases in the development of the
mixed layer, which can be related to detailed variations in the growth of the
mixing zone. Our analysis provides an explanation for the observed differences
between two and three-dimensional RT instability; the analysis also leads us to
concentrate on the RT models which (1) work equally well for both laminar and
turbulent flows, and (2) do not depend on turbulent scaling within the mixing
layer between fluids. These candidate RT models are based on point sources
within bubbles (or plumes) and interaction with each other (or the background
flow). With this motivation, we examine the evolution of single plumes, and
relate our numerical results (of single plumes) to a simple analytical model
for plume evolution.


title: Information loss in an optimal maximum likelihood decoding

abstract:
  The mutual information between a set of stimuli and the elicited neural
responses is compared to the corresponding decoded information. The decoding
procedure is presented as an artificial distortion of the joint probabilities
between stimuli and responses. The information loss is quantified. Whenever the
probabilities are only slightly distorted, the information loss is shown to be
quadratic in the distortion

categories: physics.bio-ph cond-mat.dis-nn physics.data-an q-bio.QM


title: Zipf's law in human heartbeat dynamics

abstract:
  It is shown that the distribution of low variability periods in the activity
of human heart rate typically follows a multi-scaling Zipf's law. The presence
or failure of a power law, as well as the values of the scaling exponents, are
personal characteristics depending on the daily habits of the subjects.
Meanwhile, the distribution function of the low-variability periods as a whole
discriminates efficiently between various heart pathologies. This new technique
is also applicable to other non-linear time-series and reflects these aspects
of the underlying intermittent dynamics, which are not covered by other methods
of linear- and nonlinear analysis.


title: Derivation of the Lorentz Transformations

abstract:
  The Lorentz Transformations are derived without any linearity assumptions and
without assuming that y and z coordinates transform in a Galilean manner.
Status of the invariance of the speed of light is reduced from a foundation of
the Special Theory of Relativity to just a property which allows to determine a
value of the physical constant. While high level of rigour is maintained, this
paper should be accessible to a second year university physics student.


title: The wave packet propagation using wavelets

abstract:
  It is demonstrated that the wavelets can be used to considerably speed up
simulations of the wave packet propagation in multiscale systems. Extremely
high efficiency is obtained in the representation of both bound and continuum
states. The new method is compared with the fast Fourier algorithm. Depending
on ratios of typical scales of a quantum system in question, the wavelet method
appears to be faster by a few orders of magnitude.


title:
Sucrose Solutions as Prospective Medium to Study the Vesicle Structure:
  SAXS and SANS study

abstract:
  The possibility to use sucrose solutions as medium for X-ray and neutron
small-angle scattering experiments has been explored for
dimyristoylphosphatidylcholine (DMPC) vesicles and mixed DMPC/C_(12)E_(8)
aggregates. The influence of sucrose concentration on phospholipid vesicles
size and polydispersity has been investigated by complimentary X-ray and
neutron scattering. Sucrose solutions decreased vesicle size and polydispersity
and increased a contrast between phospholipid membrane and bulk solvent
sufficiently for X-rays. 40% sucrose in H2O increased X-ray contrast by up to
10 times compared to pure H2O. The range of sucrose concentration 30%-40%
created the best experimental conditions for the X-ray small-angle experiment
with phospholipid vesicles.

categories: physics.bio-ph cond-mat.soft physics.chem-ph q-bio


title:
A Sucrose Solution Application to the Study of Model Biological
  Membranes

abstract:
  The small-angle X-ray and neutron scattering, time resolved X-ray small-angle
and wide-angle diffraction coupled with differential scanning calorimetry have
been applied to the investigation of unilamellar and multilamellar
dimyristoylphosphatidylcholine (DMPC) vesicles in sucrose buffers with sucrose
concentrations from 0 to 60%. Sucrose buffer decreased vesicle size and
polydispersity and increased an X-ray contrast between phospholipid membrane
and bulk solvent sufficiently. No influence of sucrose on the membrane
thickness or mutual packing of hydrocarbon chains has been detected. The region
of sucrose concentrations 30%-40% created the best experimental conditions for
X-ray small-angle experiments with phospholipid vesicles.


title: A quasi classical approach to electron impact ionization

abstract:
  A quasi classical approximation to quantum mechanical scattering in the
Moeller formalism is developed. While keeping the numerical advantage of a
standard Classical--Trajectory--Monte--Carlo calculation, our approach is no
longer restricted to use stationary initial distributions. This allows one to
improve the results by using better suited initial phase space distributions
than the microcanonical one and to gain insight into the collision mechanism by
studying the influence of different initial distributions on the cross section.
A comprehensive account of results for single, double and triple differential
cross sections for atomic hydrogen will be given, in comparison with experiment
and other theories.


title:
Drop Formation in a One-Dimensional Approximation of the Navier-Stokes
  Equation

abstract:
  We consider the viscous motion of a thin, axisymmetric column of fluid with a
free surface. A one-dimensional equation of motion for the velocity and the
radius is derived from the Navier-Stokes equation. We compare with recent
experiments on the breakup of a liquid jet and on the bifurcation of a drop
suspended from an orifice. The equations form singularities as the fluid neck
is pinching off. The nature of the singularities is investigated in detail.


title:
Comment on ``Multiple scattering in a reflecting cavity: Application to
  fish counting in a tank [J. Acoust. Soc. Am. {\bf 109}, 2587-2597 (2001)]"

abstract:
  This paper presents a comment on the recent work on fish counting in a tank
(J. Acoust. Soc. Am. 109, 2587-2597 (2001)). It is pointed out that there are
ambiguities with the counting method.


title:
Relationship between sunspot number and total annual precipitation at
  Izana (Tenerife): Maximum precipitation prediction with three year lagged
  sunspots?

abstract:
  A possible relationship between sunspot number and total annual precipitation
from the Izana Observatory has been found. The annual precipitation period
ranges from 1916 to 1998, thus including nearly eight 11-year solar cycles.
  When points of total precipitation for a given year at Izana are plotted on
the ordinate axis versus the yearly sunspot number on the abcisa axis three
years back from the precipitation one, nearly all of them lie in the lower left
hand corner of the diagram. This seems to indicate a relationship between the
above mentioned variables.
  If this relationship is confirmed it would permit the prediction of a maximum
annual precipitation at Izana three years in advance.


title: Reconstruction of dynamical equations for traffic flow

abstract:
  Traffic flow data collected by an induction loop detector on the highway
close to Koeln-Nord are investigated with respect to their dynamics including
the stochastic content. In particular we present a new method, with which the
flow dynamics can be extracted directly from the measured data. As a result a
Langevin equation for the traffic flow is obtained. From the deterministic part
of the flow dynamics, stable fixed points are extracted and set into relation
with common features of the fundamental diagram.


title: Being at Rest

abstract:
  As a subject, an observer is fundamentally at rest in a reference frame, and
this being at rest allows for measuring the motion of physical objects.
Exploring the experience of centrifugal force brings to the fore the natural
inclination to see oneself at rest in a reference frame. The discrepancy
between the experience of centrifugal force and its lack of fundamental
significance in Newton's laws of motion points toward the importance of the
observer as a subject in his or her own reference frame, specifically the
observer's experience of being at rest in this reference frame. In addition,
the observer's being at rest for himself or herself in a reference frame is a
central feature of both special and general relativity.


title: On Thermal Sensation and Entropy

abstract:
  A neurophysiological thesis is proposed for thermal sensitivity that accounts
for the disorder in physical processes that is fundamental to temperature.
There is likely some form of thermal equilibrium rapidly established between
thermoreceptors and the external environment local to those thermoreceptors
that accounts for gauging the temperature accurately within a certain range.


title: Hydrodynamic Singularities

abstract:
  We give a brief overview of the physical significance of singularities in
fluid mechanics.


title: Correlated noise induced control of prey extinction

abstract:
  We study the steady state properties of a phenomenological two-state predator
model in presence of correlated Gaussian white noise. Based on the
corresponding Fokker-Planck equation for probability distribution function the
steady state solution of the probability distribution function and its extrema
have been investigated. We show for a typical value of noise correlation there
is a giant loss of bistability which in turn prevents the prey population from
going into extinction.


title:
Results from a Prototype Permanent Magnet Dipole-Quadrupole Hybrid for
  the PEP-II B-Factory

abstract:
  We describe the construction of a prototype hybrid permanent magnet dipole
and quadruple. The magnet consists of two concentric rings of SmCo magnetic
material 5 cm in length. The outer ring is made of 16 uniformly magnetized
blocks assembled as a Halbach dipole and the inner ring has 32 blocks oriented
in a similar fashion so as to generate a quadruple field. The resultant
superimposed field is an offset quadruple field which allows us to center the
field on the high-energy beam in the interaction region of the PEPII B factory.
The dipole blocks are glued to the inside surface of an outer support collar
and the quadruple blocks are held in a fixture that allows radial adjustment of
the blocks prior to potting the entire assembly with epoxy. An extensive
computer model of the magnet has been made and from this model we developed a
tuning algorithm that allowed us to greatly reduce the n=3-17 harmonics of the
magnet.


title: Mini-stop bands in single-defect photonic crystal waveguides

abstract:
  We numerically study single-defect photonic crystal waveguides obtained from
a triangular lattice of air holes in a dielectric background. It is found that,
for medium-high air filling ratios, the transmission has very small values in
narrow frequency regions lying inside the photonic band gap - the so-called
mini-stop bands. Two types of mini-stop bands are shown to exist; one of which
is due to the multimode nature of the waveguide. Their dependence on the length
of the waveguide and on the air filling ratio is presented.


title: Development of a Detector Control System for the ATLAS Pixel Detector

abstract:
  The innermost part of the ATLAS experiment will be a pixel detector
containing around 1750 individual detector modules. A detector control system
(DCS) is required to handle thousands of I/O channels with varying
characteristics. The main building blocks of the pixel DCS are the cooling
system, the power supplies and the thermal interlock system, responsible for
the ultimate safety of the pixel sensors. The ATLAS Embedded Local Monitor
Board (ELMB), a multi purpose front end I/O system with a CAN interface, is
foreseen for several monitoring and control tasks. The Supervisory, Control And
Data Acquisition (SCADA) system will use PVSS, a commercial software product
chosen for the CERN LHC experiments. We report on the status of the different
building blocks of the ATLAS pixel DCS.


title: The group structure bases of a foundational approach to physics

abstract:
  Based on a fundamental symmetry between space, time, mass and charge, a
series of group structures of physical interest is generated, ranging from C2
to E8. The most significant result of this analysis is a version of the Dirac
equation combining quaternions and multivariate vectors, which is already
second quantized and intrinsically supersymmetric, and which automatically
leads to a symmetry breaking, with the creation of specific particle structures
and a mass-generating mechanism.


title: Bayesian inference for inverse problems

abstract:
  Traditionally, the MaxEnt workshops start by a tutorial day. This paper
summarizes my talk during 2001'th workshop at John Hopkins University. The main
idea in this talk is to show how the Bayesian inference can naturally give us
all the necessary tools we need to solve real inverse problems: starting by
simple inversion where we assume to know exactly the forward model and all the
input model parameters up to more realistic advanced problems of myopic or
blind inversion where we may be uncertain about the forward model and we may
have noisy data. Starting by an introduction to inverse problems through a few
examples and explaining their ill posedness nature, I briefly presented the
main classical deterministic methods such as data matching and classical
regularization methods to show their limitations. I then presented the main
classical probabilistic methods based on likelihood, information theory and
maximum entropy and the Bayesian inference framework for such problems. I show
that the Bayesian framework, not only generalizes all these methods, but also
gives us natural tools, for example, for inferring the uncertainty of the
computed solutions, for the estimation of the hyperparameters or for handling
myopic or blind inversion problems. Finally, through a deconvolution problem
example, I presented a few state of the art methods based on Bayesian inference
particularly designed for some of the mass spectrometry data processing
problems.


title:
Marked variability in modern-time gravitational data indicates a large
  secular increase in the mass of ponderable bodies

abstract:
  In spite of two hundred years of considerable efforts directed towards
improvement in the experimental techniques, gravitational measurements have
provided unsettled results for Newton's gravitational constant G. Analysis of
the published (over ~75 years) small-scale gravitational measurements,
presented in this report, unveils a large secular increase in the gravitational
force, that reveals itself as a formal increase in the Newton's constant G at a
rate 'G dot per G' = (1.43 +-0.08) x 10^(-5) year^(-1). Since its
interpretation as a true 'G dot per G' effect is excluded by laser and radar
ranging to the Moon and the interior planets as well as by double-pulsar
studies, which all put tight limits on any variation in G, this large secular
effect appears to originate in a temporal increase of gravitational masses due
to, e.g., capture of mass from a hypothetical cold dark matter halo of the Sun.
By virtue of the equivalence principle, the secular mass increase leads
naturally to modifications of the Newtonian dynamics in the Solar System, as it
predicts a cosmic deceleration of moving bodies dependent upon their speed. In
particular, it predicts for the Pioneer 10/11 spacecraft an anomalous, nearly
constant acceleration of -(11.0 +-1.8) x 10^(-10) m/s^2, in agreement with the
published experimental value of -(8.7 +- 0.9) x 10^(-10) m/s^2. Dynamical
effects of this kind have been also detected in the motion of other spacecraft
and artificial satellites, but not in the motion of large and/or old objects in
the Solar System.


title:
Enhancement of energy relaxation rates near metal-coated dielectric
  cylinders

abstract:
  The electromagnetic modes and their field distributions are evaluated for a
dielectric cylindrical structure embedded in another dielectric, with a thin
metallic film at the cylinder/dielectric interface. These modes provide energy
relaxation channels for excited dipole emitters located inside or outside the
cylinder. Significantly, we find that the emission rate is sensitive to the
magnitude of the electron density of the metallic film coating. For typical
parameter values, we find large enhancements of the emission rate, which can be
in excess of three orders of magnitude, relative to the case in the absence of
the film, arising at specific ranges of electron density. The theory is shown
to conform with known limits, including the high density (perfect conductor)
limit and the large distance (unbounded bulk) limit. The implications of the
predicted enhancement due to the metal coating for the purpose of guiding atoms
within such microstructures are pointed out.


title: Phase Transition of DNA-Linked Gold Nanoparticle

abstract:
  Melting and hybridization of DNA-capped gold nanoparticle networks are
investigated with optical absorption spectroscopy. Single-stranded, 12-base
DNA-capped gold nanoparticles are linked with complementary, single-stranded,
24-base linker DNA to form particle networks. Compared to free DNA, a sharp
melting transition is seen in these networked DNA-nanoparticle systems. The
sharpness is explained by percolation transition phenomena.


title: Theory of Drop Formation

abstract:
  We consider the motion of an axisymmetric column of Navier-Stokes fluid with
a free surface. Due to surface tension, the thickness of the fluid neck goes to
zero in finite time. After the singularity, the fluid consists of two halves,
which constitute a unique continuation of the Navier-Stokes equation through
the singular point. We calculate the asymptotic solutions of the Navier-Stokes
equation, both before and after the singularity. The solutions have scaling
form, characterized by universal exponents as well as universal scaling
functions, which we compute without adjustable parameters.


title:
Statistical Properties of Fano Resonances in Atomic and Molecular
  Photoabsorption

abstract:
  Statistical properties of Fano resonances occurring in photoabsorption to
highly excited atomic or molecular states are derived. The situation with one
open and one closed channel is analyzed when the classical motion of the
excited complex in the closed channel is chaotic. The closed channel subspace
is modeled by random matrix theory. The probability distribution of the Fano
parameter is derived both for the case of time reversal symmetry (TRS) and
broken time reversal symmetry. For the TRS case the area distribution under a
resonance profile relevant for low resolution experiments is discussed in
detail.


title: On the Use of CORBA in High Level Software Applications at the SLS

abstract:
  Beam dynamics applications at the Swiss Light Source (SLS) have benefitted
from a distributed computing environment in which the Common Object Request
Broker Architecture (CORBA) forms the middleware layer and access point to
several different software components.A suite of remote CORBA server objects
provides the client with a convenient and uniform interface to the CDEV (Common
DEVice) controls library, the TRACY accelerator physics package, the Oracle
database, and en event logging facility. Use is made of methods provided by the
CORBA Portable Object Adaptor for accessing ORB functions, such as object
activation and object persistence, the Implementation Repository for the
automatic reactivation of servers, and the CORBA Event Service for the
propagation of controls and physics data. An account of the CORBA framework, as
used by applications in the commissioning and first operation of the SLS, is
presented.


title:
High Performance Electrostatic Sensors and Actuators for LISA Proof Mass
  Control

abstract:
  This document contains two presentations which describe the working
principles of a class of electrostatic multidimensional sensors and force
actuators. The subject of the study is the search of the most effective methods
for measuring the position of a cubical conducting proof mass which floats in a
weightless environment. The same proof mass must be controlled with a feedback
loop by applying forces with the same set of electrodes. For more information
please see the web site: http://lisa.jpl.nasa.gov/


title: Penalized maximum likelihood for multivariate Gaussian mixture

abstract:
  In this paper, we first consider the parameter estimation of a multivariate
random process distribution using multivariate Gaussian mixture law. The labels
of the mixture are allowed to have a general probability law which gives the
possibility to modelize a temporal structure of the process under study. We
generalize the case of univariate Gaussian mixture in [Ridolfi99] to show that
the likelihood is unbounded and goes to infinity when one of the covariance
matrices approaches the boundary of singularity of the non negative definite
matrices set. We characterize the parameter set of these singularities. As a
solution to this degeneracy problem, we show that the penalization of the
likelihood by an Inverse Wishart prior on covariance matrices results to a
penalized or maximum a posteriori criterion which is bounded. Then, the
existence of positive definite matrices optimizing this criterion can be
guaranteed. We also show that with a modified EM procedure or with a Bayesian
sampling scheme, we can constrain covariance matrices to belong to a particular
subclass of covariance matrices. Finally, we study degeneracies in the source
separation problem where the characterization of parameter singularity set is
more complex. We show, however, that Inverse Wishart prior on covariance
matrices eliminates the degeneracies in this case too.


title:
Combined CI+MBPT calculations of energy levels and transition amplitudes
  in Be, Mg, Ca, and Sr

abstract:
  Configuration interaction (CI) calculations in atoms with two valence
electrons, carried out in the V(N-2) Hartree-Fock potential of the core, are
corrected for core-valence interactions using many-body perturbation theory
(MBPT). Two variants of the mixed CI+MBPT theory are described and applied to
obtain energy levels and transition amplitudes for Be, Mg, Ca, and Sr.


title: Thermal instability of an optically thin dusty plasma

abstract:
  We investigate the role of thermal instability, arising from radiative
cooling of an optically thin, dusty plasma, by linear stability analysis. The
corresponding isobaric stability condition for condensation mode is found to be
modified significantly by the degree of ionization and concentration of finite
sized, relatively heavy, and negatively charged dust particles. It has been
shown that though the fundamental wave mode is similar in nature to the one in
absence of dust particles, a new dust-wave mode can propagate in such a plasma.
It is conjectured that the presence of negatively charged dust particles may
considerably affect the stability of various astrophysical structures against
thermal instability, which can not be explained with the help of gravitational
instability.


title:
Transverse emittance measurements on an S-band photoinjector rf electron
  gun

abstract:
  Proposed fourth generation light sources using SASE FELs to generate short
pulse, coherent, X-rays require demonstration of high brightness electron
sources. The Gun Test Facility (GTF) at SLAC was built to test high brightness
sources for the proposed Linac Coherent Light Source at SLAC. The transverse
emittance measurements are made at nearly 30 MeV by measuring the spot size on
a YAG screen using the quadrupole scan technique. The emittance was measured to
vary from 1 to 3.5 mm-mrad as the charge is increased from 50 to 350 pC using a
laser pulse width of 2 ps FWHM. The measurements are in good agreement with
simulation results using the LANL version of PARMELA.


title:
Evolution of induced axial magnetization in a two-component magnetized
  plasma

abstract:
  In this paper, the evolution of the induced axial magnetization due to the
propagation of an electromagnetic (em) wave along the static background
magnetic field in a two-component plasma has been investigated using the Block
equation. The evolution process induces a strong magnetic anisotropy in the
plasma medium, depending nonlinearly on the incident wave amplitude. This
induced magnetic anisotropy can modify the dispersion relation of the incident
em wave, which has been obtained in this paper. In the low frequency Alfven
wave limit, this dispersion relation shows that the resulting phase velocity of
the incident wave depends on the square of the incident wave amplitude and on
the static background magnetic field of plasma. The analytical results are in
well agreement with the numerically estimated values in solar corona and
sunspots.


title:
Design of a Distributed Control System Based on CORBA and JAVA for a New
  RIB facility at LNL

abstract:
  SPES (Study for the Production of Exotic Species) is a LNL project that will
produce by the end of this year the conceptual design of a specialized facility
for Radioactive Ion Beam (RIB) originated by fission fragments produced by
secondary neutrons; this facility will be characterized by moderate size,
performance and cost and will allow to produce also intense neutron beams for
activities both in fundamental and applied Nuclear Physics [1]. In the context
of this design study and tightly related to medium size of this facility the
architecture of a distributed control system using the Common Object Request
Broker Architecture (CORBA) [2] as middleware framework and JAVA [3] as main
programming language was investigated for the core sub-systems (diagnostics,
optics, RF-control) of the primary accelerator. The performance of CORBA for
the high level control system was measured in different conditions and showed
to be sufficient to cover the requirements for remote operations, because all
feedback loops will be performed either in specialized hardware or by dedicated
real-time embedded controllers. A minimal programming effort, a good level of
modularity and long-term maintenance were the reasons to choose JAVA and its
related application builders as the main programming language for the Graphical
User Interface (GUI) and the middleware implementations of this project.


title: Quantum theory of spontaneous emission by real moving atoms

abstract:
  We outline the solution of a fundamental problem in quantum theory which has
hitherto lacked a proper solution, namely finding the requisite quantum
theoretical framework guaranteeing that the calculated inverse spontaneous
emission rate of a moving atom, as a composite system of charged particles
interacting with the Maxwell field, is slowed down exactly as in time dilation.


title:
Damping of transversal plasma-electron oscillations and waves in
  low-collision electron-ion plasmas

abstract:
  Previously developed method for finding asymptotic solutions of Vlasov
equations using two-dimensional (in coordinate x and time t) Laplace transform
is here applied to consider transversal oscillations and waves in low-collision
quasi-neutral (n_i \simeq n_e) Maxwellian electron-ion plasmas. We obtain two
branches of electron waves: the ubiquitous one of high-frequency and
high-velocity oscillations and the unusual low-velocity one. Taking into
account Coulomb collisions in the limit m_e << m_i, \bar{v_i} << \bar{v_e}, and
T_e m_e << T_i m_i results in expressions for transversal plasma-electron
oscillation/wave decrements with a damping of the low-velocity electron branch
\sim n_i^{1/3}/\bar{v}_e^{4/3}, where n_i is the ion density and \bar{v}_e is
the mean electron velocity. It ought to rehabilitate Vlasov principal value
prescription for relevant integrals, but to supplement it with representation
of an asymptotical solution as a sum of exponents (not a single one).
"Non-damping" kinematical waves in low-collision plasma transform in the
damping ones at reasonably chosen iteration process.


title:
Propagation of electromagnetically generated wake fields in
  inhomogeneous magnetized plasmas

abstract:
  Generation of wake fields by a short electromagnetic pulse in a plasma with
an inhomogeneous background magnetic field and density profile is considered,
and a wave equation is derived. Transmission and reflection coefficients are
calculated in a medium with sharp discontinuities. Particular attention is
focused on examples where the longitudinal part of the electromagnetic field is
amplified for the transmitted wave. Furthermore, it is noted that the wake
field can propagate out of the plasma and thereby provide information about the
electron density profile. A method for reconstructing the background density
profile from a measured wake field spectrum is proposed and a numerical example
is given.


title:
Electromagnetic induction and damping - quantitative experiments using
  PC interface

abstract:
  A bar magnet, attached to an oscillating system, passes through a coil
periodically, generating a series of emf pulses. A novel method is described
for the quantitative verification of Faraday's law which eliminates all errors
associated with angular measurements, thereby revealing delicate features of
the underlying mechanics. When electromagnetic damping is activated by
short-circuiting the coil, a distinctly linear decay of oscillation amplitude
is surprisingly observed. A quantitative analysis reveals an interesting
interplay of the electromagnetic and mechanical time scales.


title:
On non-equivalence of Lorentz and Coulomb gauges within classical
  electrodynamics

abstract:
  It is shown that the well-known procedure for proving the equivalence of the
expressions for the electric field calculated using the Lorentz and Coulomb
gauges is incorrect. The difference between the two gauges is due to the
difference in the speed of propagation of a disturbance of the scalar
potential. As an auxiliary result, it is proven that the solution for the
electric field cannot be obtained directly from the Maxwell equations, i.e.
without introducing the scalar and vector potentials.


title:
Bayesian source separation with mixture of Gaussians prior for sources
  and Gaussian prior for mixture coefficients

abstract:
  In this contribution, we present new algorithms to source separation for the
case of noisy instantaneous linear mixture, within the Bayesian statistical
framework. The source distribution prior is modeled by a mixture of Gaussians
[Moulines97] and the mixing matrix elements distributions by a Gaussian
[Djafari99a]. We model the mixture of Gaussians hierarchically by mean of
hidden variables representing the labels of the mixture. Then, we consider the
joint a posteriori distribution of sources, mixing matrix elements, labels of
the mixture and other parameters of the mixture with appropriate prior
probability laws to eliminate degeneracy of the likelihood function of variance
parameters and we propose two iterative algorithms to estimate jointly sources,
mixing matrix and hyperparameters: Joint MAP (Maximum a posteriori) algorithm
and penalized EM algorithm. The illustrative example is taken in [Macchi99] to
compare with other algorithms proposed in literature. Keywords: Source
separation, Gaussian mixture, classification, JMAP algorithm, Penalized EM
algorithm.


title:
Investigation Solvation Dynamics and Isomerization of Dye IR-140 Using
  pump supercontinuum-probing Technique

abstract:
  The solvation dynamics and isomerization process of an organic dye, IR-140,
in polar solvents and nonpolar solvents have been investigated using pump
supercontinuum-probing (PSCP) technique. In all solvents, the dynamics exhibits
solvent-dependent. Solvent induced spectral shifts of the absorption and
emission spectra of IR-140 have also been studied in a variety of solvents. At
the same time, the photoisomerization process has been examined. The
approximate energy-band structure of IR-140 was also supposed firstly.


title:
Model selection for inverse problems: Best choice of basis functions and
  model order selection

abstract:
  A complete solution for an inverse problem needs five main steps: choice of
basis functions for discretization, determination of the order of the model,
estimation of the hyperparameters, estimation of the solution, and finally,
characterization of the proposed solution. Many works have been done for the
three last steps. The first two have been neglected for a while, in part due to
the complexity of the problem. However, in many inverse problems, particularly
when the number of data is very low, a good choice of the basis functions and a
good selection of the order become primary. In this paper, we first propose a
complete solution within a Bayesian framework. Then, we apply the proposed
method to an inverse elastic electron scattering problem.


title: Entropy in Signal Processing (Entropie en Traitement du Signal)

abstract:
  R\'esum\'e: Le principal objet de cette communication est de faire une
r\'etro perspective succincte de l'utilisation de l'entropie et du principe du
maximum d'entropie dans le domaine du traitement du signal. Apr\`es un bref
rappel de quelques d\'efinitions et du principe du maximum d'entropie, nous
verrons successivement comment l'entropie est utilis\'ee en s\'eparation de
sources, en mod\'elisation de signaux, en analyse spectrale et pour la
r\'esolution des probl\`emes inverses lin\'eaires. Mots cl\'es : Entropie,
Entropie crois\'ee, Distance de Kullback, Information mutuelle, Estimation
spectrale, Probl\`emes inverses
  Abstract: The main object of this work is to give a brief overview of the
different ways the entropy has been used in signal and image processing. After
a short introduction of different quantities related to the entropy and the
maximum entropy principle, we will study their use in different fields of
signal processing such as: source separation, model order selection, spectral
estimation and, finally, general linear inverse problems. Keywords : Entropy,
Relative entropy, Kullback distance, Mutual information, Spectral estimation,
Inverse problems.


title: The SNS Cryogenic Control System: Experiences in Collaboration

abstract:
  The cryogenic system for the Spallation Neutron Source (SNS) is designed by
Jefferson Laboratory (JLab) personnel and is based on the existing JLab
facility. Our task is to use the JLab control system design [2] as much as
practical while remaining consistent with SNS control system standards. Some
aspects of the systems are very similar, including equipment to be controlled,
the need for PID loops and automatic sequences, and the use of EPICS. There are
differences in device naming, system hardware, and software tools. The
cryogenic system is the first SNS system to be developed using SNS standards.
This paper reports on our experiences in integrating the new and the old.


title:
Polarisation Patterns and Vectorial Defects in Type II Optical
  Parametric Oscillators

abstract:
  Previous studies of lasers and nonlinear resonators have revealed that the
polarisation degree of freedom allows for the formation of polarisation
patterns and novel localized structures, such as vectorial defects. Type II
optical parametric oscillators are characterised by the fact that the
down-converted beams are emitted in orthogonal polarisations. In this paper we
show the results of the study of pattern and defect formation and dynamics in a
Type II degenerate optical parametric oscillator for which the pump field is
not resonated in the cavity. We find that traveling waves are the predominant
solutions and that the defects are vectorial dislocations which appear at the
boundaries of the regions where traveling waves of different phase or
wave-vector orientation are formed. A dislocation is defined by two topological
charges, one associated with the phase and another with the wave-vector
orientation. We also show how to stabilize a single defect in a realistic
experimental situation. The effects of phase mismatch of nonlinear interaction
are finally considered.


title: The Evolution of the DELTA Control System

abstract:
  This paper is about reaching EPICS with the DELTA Control System and other
projects in the DELTA Control System.


title: Upgrade of the Photon Beamline Control System on the SRS

abstract:
  The SRS is a 2GeV synchrotron light source with 14 beamlines serving
approximately 34 experimental stations. Control of the major elements of the
beamlines (vacuum pumps, gauges, valves and radiation stops) is the
responsibility of the main SRS Control System. As part of the long-term upgrade
plan for the SRS Control System a large programme of work has been undertaken
to modernize beamline control. This work included: development of Linux based
PC front end computers to interface to the existing CAMAC I/O system,
replacement of the user interface by graphical synoptic diagrams running on
Windows NT PCs, development of an ActiveX control for parameter display/control
and a cache server to reduce loading on the rest of the control system. This
paper describes the major components of the project; the techniques used to
manage the new PCs and discusses some of the problems encountered during
development.


title: Distributed Power Supply Control and Monitoring System

abstract:
  An extensible power supply control and monitoring system has been developed
at Fermilab's Technical Division as a result of requirements to control and
monior power supplies of various types from within many different applications.
This system, deployed as a network service, provides uniform programming and
user interfaces for various types of power supplies, ranging from 20A to 30kA.
It allows for a concurrent multi-user access, with at most one application
granted controlling capabilities at a time. Users can control and monitor the
state of a power supply as well as monitor generated current by: a) sending
separate requests to the service via provided C/C+ and Java APIs, b) uploading
current control programs written in a specialized ramp profile description
language to be interpreted by the system, c) scripting using a provided set of
programs, and d) using supplied GUIs. In addition, special programs are
available to monitor and log all control requests being sent to the service and
to provide traces of current. Also, a graphical simulator is provided to
facilitate testing of ramp profiles developed by the user.


abstract:
  The LIGO Interferometer Sensing and Control System (ISC) is a large and
highly distributed Multiple Input Multiple Output (MIMO) control system that is
used to control the length and alignment degrees of freedom of the
interferometers. The 4 kilometer Fabry-Perot cavity lengths are controlled to
better than 10-13 meters (rms) and the angular degrees of freedom are
controlled to better than 10-8 radians. This paper will describe the real-time
digital servo control systems that have been designed, developed and
implemented for the LIGO Length Sensing and Control (LSC) [1] and Alignment
Sensing and Control (ASC) [2] systems. In addition, the paper will describe how
these controls, along with the suspended optic controls [3], have been
integrated into the overall LIGO control and data acquisition system [4].


title: HOTLink Rack Monitor

abstract:
  A remote data acquisition chassis, called a HOTLink Rack Monitor, HRM, has
been developed for use in the Fermilab control system. This chassis provides
for 64 analog input channels, 8 analog output channels, and 8 bytes of digital
I/O. The interface to the host VMEbus crate is by way of a 320 MHz HOTLink
serial connection to a PMC mezzanine module. With no processor intervention,
all data sources in the remote chassis are read at 100 microsec intervals,
timestamped, and stored in a 2 MB circular buffer on the PMC module. In
operation, the memory always contains the most recent 16k samples of 10 kHz
data from all 64 analog input channels. An expansion module that resides in the
HRM chassis records snapshot data for 8 analog channels, each channel
consisting of up to 16k readings, digitized at rates up to 10 MHz. Snapshot
data is also returned and stored in buffers on the PMC module. Because the HRM
presents a memory-mapped interface to the host, it is independent of the
operating system and may be used in any system that supports PMC mezzanine
modules.


title: Control System for Electromagnet Power Supplies

abstract:
  A set of power supplies (PS) with output power rated from 100 W up to 10 kW
for electromagnets powering was developed. These PS have range of current
tuning of 60-80 db with high accuracy (error should be less than 0,01%). Some
types of power supplies have bipolar output current. The report will describe a
set of unified embedded devices for control and measurements of PS incorporated
into distributed control systems. These embedded devices includes DAC, ADC with
multiplexers and status Input/Output registers. The devices include
microprocessor and allow work with minimal host involving. This capability
decreases traffic, provides synchronous tuning of all electromagnet elements of
particle accelerator and increases reliability of entire system.


title: Preliminary Design of Muses Control System Based on RT-Corba and Java

abstract:
  Common Object Request Broker Architecture (CORBA) based control system has
been utilized for the first phase of RIKEN-RI Beam Factory (RIBF) [1] at the
developing stage. Software sharing with Jozef Stefan Institute (JSI) in
Slovenia via CORBA/JavaBeans has been successfully demonstrated. Accelerator
Beans (Abeans) [2] components developed in JDK1.2.2 have been ported to RIKEN's
CORBA server. The second phase of the RIBF project is named "Multi-Use
Experimental Storage rings" (MUSES) project, which includes an accumulator
cooler ring (ACR) and collider rings. Due to the much larger number of
controlled objects and more stringent timing requirement than the first-phase
project, we contemplate using recently established real-time (RT) CORBA
specification [3]. Summary of our efforts to test RT-CORBA with the existing
JaveBeans components and other related subjects are described in this paper.
  [1] http://ribfweb1.riken.go.jp/ [2] http://kgb.ijs.si/KGB/ [3]
http://www.omg.org/


title: Imitation of 2d quantum field theory by means of REM like models

abstract:
  An imitation of 2d field theory is formulated by means of a model on the
hierarchic tree (with branching number close to one) with the same potential
and the free correlators identical to those of 2d ones. Such a model possesses
some features of original models for certain scale invariant theories. For the
case of 2d conformal models it is possible to derive exact results. The
renormalization group equation for the free energy is a reaction-diffusion
equation, which is noise-free KPZ equation with an additional linear term. For
the case of Liouville model and strings these models on trees may be naturally
expressed via the Random Energy Model. This correspondence is used to identify
the phase structure of strings for analytical continuation of DDK expressions.
A phase transition is found for spherical strings a bit below three dimensions.


title: Front End CAMAC Controller for SLAC Control System

abstract:
  Most of the devices in the SLAC control system are accessed via interface
modules in ~450 CAMAC crates. Low-cost controllers in these crates communicate
via a SLAC-proprietary bit-serial protocol with 77 satellite control computers
("micros") within the accelerator complex. A proposed upgrade replaces the
existing Multibus-I implementation of the micro hardware with
commercial-off-the-shelf ("COTS") personal computers. For increased reliability
and ease of maintenance, these micros will move from their current electrically
noisy and environmentally challenging sites to the control center's computer
room, with only a stand-alone portion of each micro's CAMAC interface remaining
in the micro's original location. This paper describes the hardware/software
architecture of that intelligent front-end CAMAC controller and the
accompanying fiber optic link board that connects it to the PC-based micro's
PCI bus. Emphasis is placed on the hardware/software techniques employed to
minimize real-time latency for pulse-to-pulse operations that control
accelerator timing, acquire data for fast feedback loops, and change device
settings to close those loops. The controller provides the sole interface
between the COTS computing/networking environment and the existing CAMAC plant.
It also supports higher bandwidth commercial byte-serial crate controllers and
legacy BITBUS hardware.


title: Upgrade of the Control System of the IFUNAM's Pelletron Accelerator

abstract:
  In 1995 a 9SDH-2 Pelletron from NEC was installed at IFUNAM (Instituto de
Fisica, Universidad Nacional Autonoma de Mexico). Two beam lines have been
operational since then and two new lines have been built. In order to perform
the planned projects in this grown facility, an upgrading of the original
manual control system is required. The proposed new control system takes
advantage of the existing devices and incorporates the electronics needed for
the newer beam lines. The control software from NEC, has been modified to
accommodate the larger requirements. It runs on the same dedicated computer but
receives commands from a new installed host. Both computers communicate through
a local network sharing the accelerator database. The new host computer also
handles all parameters related to the new lines. In the future, the old
computer will be replaced in order to expand the possibilities of the system
and use a friendlier graphical interface. In this work we present the changes
made to the control software, the new acquisition and control devices installed
and the integration of the old and new systems. Finally, the beam control
procedure based on the analysis of the beam profile that is under development
is also shown.


title: Common Software for the ALMA project

abstract:
  The Atacama Large Millimeter Array (ALMA) is a joint project between
astronomical organizations in Europe, USA and Japan. ALMA will consist of at
least 64 12-meter antennas operating in the millimeter and sub-millimeter
wavelength range, with baselines up to 10 km. It will be located at an altitude
above 5000m in the Chilean Atacama desert[1]. The ALMA Common Software (ACS)
provides a software infrastructure common to all partners and consists of a
documented collection of common patterns in control systems and of components,
which implement those patterns. The heart of ACS is an object model of
controlled devices, called Distributed Objects (DOs), implemented as CORBA
network objects. Components such as antenna mount, power supply, etc. are
defined by means of DOs. A code generator creates Java Bean components for each
DO. Programmers can write Java client applications by connecting those Beans
with data-manipulation and visualization Beans using commercial visual
development tools or programmatically. ACS is based on the experience
accumulated with similar projects in the astronomical and particle accelerator
contexts, reusing and extending concepts and components. Although designed for
ALMA, ACS has the potential for being used in other new control systems and
other distributed software projects, since it implements proven design patterns
using state of the art, stable and reliable technology.


title: Speculations on a Unified Theory of Matter and Mind

abstract:
  Physics is so successful today in understanding the nature of matter. What
can it say about mind ? Is it possible to have a unified theory of matter and
mind within the framework of modern science ? Is Consciousness an accident or
is it a natural consequence of laws of nature ? Are these laws of nature the
same as the laws of physics ? We make an attempt here to unify mind with matter
based on an extended formalism borrowed from Quantum theory where information
plays a more fundamental role than matter or thought.


title:
Computational Modeling in Support of the National Ignition Facilty
  Operations

abstract:
  Numerical simulation of the National Ignition Facility (NIF) laser
performance and automated control of the laser setup process are crucial to the
project's success. These functions will be performed by two closely coupled
computer code: the virtual beamline (VBL) and the laser performance operations
model (LPOM).


title: Reimplementing the EPICS Static Database Access Library

abstract:
  The Static Database Access library was first introduced in EPICS
(Experimental Physics and Industrial Control System) Release 3.11 in 1994. It
provides an application program interface (API) for database configuration
tools written in C to manipulate database record definitions and is used for
various tasks within the core EPICS software. This paper describes the
structure of a replacement for the original library that adds a native C++ API
and will make some future enhancements to EPICS significantly easier to
implement.


title: FEL injector control system on the base of EPICS

abstract:
  The control system of the 1.5 MeV FEL injector is built on the base of ported
EPICS. It uses low-cost hardware: personal computers with the processor Intel
x86 and CAMAC equipment produced by our institute. At present time, the
distributed control system includes one Pentium at OPerator Interface (OPI)
level and two IOC (Input Output Controllers) under supervision of the real time
operating system LynxOS/x86 at the low-level. Each IOC is used for monitoring
of autonomous parts of the injector. The first IOC operates the Radio Frequency
(RF) system. The second IOC operates the injector equipment


title: The SNS Run Permit System

abstract:
  The Spallation Neutron Source (SNS) is an accelerator-based neutron source
being built in Oak Ridge, Tennessee, by the U.S. Department of Energy. The SNS
will provide the most intense pulsed neutron beams in the world for scientific
research and industrial development. The facility is scheduled for completion
in 2006. The project is a collaboration between Lawrence Berkeley National Lab,
Argonne National Lab, Los Alamos National Lab, Oak Ridge National Lab,
Brookhaven National Lab, and Jefferson Lab. The Run Permit System (RPS) is a
software based system which has several key functions critical for safe
operation of the machine. It coordinates machine mode and beam parameter
changes with the timing system, verifies the Machine Protection System (MPS)
hardware configuration, and provides an interface for masking MPS hardware
inputs when necessary. This paper will describe the primary functionality of
the Run Permit System and the interface between the Run Permit System, the
Machine Protection System, and the timing system.


title: EPICS for PDAs

abstract:
  With the advent of readily available wireless communications and small
hand-held computers, commonly known as personal digital assistants (PDAs), it
is interesting to consider using these portable devices to access a control
system. We have successfully ported the Experimental Physics and Industrial
Control System (EPICS) to Windows CE 3.0 (WCE) for the Pocket PC (PPC), and
this paper describes the issues involved. The PPC was chosen because the WCE
application programming interface (API) for the PPC is a subset of the Win32
API, which EPICS already supports, and because PPC devices tend to have more
memory than other PDAs. PDAs provide several ways to connect to a network,
using wired or wireless Compact Flash or PCMCIA Ethernet cards and modems. It
is the recent advent of readily available wireless networks that makes using
the portable PDA interesting. The status and issues surrounding the various
kinds of wireless systems available are presented.


title: EPICS: A Retrospective on Porting iocCore to Multiple Operating Systems

abstract:
  An important component of EPICS (Experimental Physics and Industrial Control
System) is iocCore, which is the core software in the IOC (input/output
controller) front-end processors. At ICALEPCS 1999 a paper was presented
describing plans to port iocCore to multiple operating systems. At that time
iocCore only supported vxWorks, but now it also supports RTEMS, Solaris, Linux,
and WinNT. This paper describes some key features of how iocCore supports
multiple operating systems.


title: Stability of excited atoms in small cavities

abstract:
  We consider a system consisting of an atom in the approximation of a harmonic
oscillator of frequency $\bar{\omega}$, coupled to the scalar potential inside
a spherical reflecting cavity of radius R. We use {\it dressed} states
introduced in a previous publication [Andion, Malbouisson and Matos Neto, J.
Phys. A34, 3735 (2001)], which allow a non-perturbative unified description of
the atom radiation process, in both cases, of a finite or an arbitrarily large
cavity. We perform a study of the energy distribution in a small cavity, with
the initial condition that the atom is in the first excited state and we
conclude for the quasi-stability of the excited atom. For instance, for a
frequency $\bar{\omega}$ of the order $\bar{\omega}\sim 4.00\times 10^{14}/s$
(in the visible red), starting from the initial condition that the atom is in
the first excited level, we find that for a cavity with diameter $2R\sim
1.0\times 10^{-6}m$, the probability that the atom be at any time still in the
first excited level, will be of the order of 97%. For a typical microwave
frequency $\bar{\omega}\sim 2,00\times 10^{10}/s$ we find stability in the
first excited state also of the order of 97% for a cavity radius $R\sim
1.4\times 10^{-2}m$.

categories: physics.atom-ph hep-ph hep-th physics.optics quant-ph


title: The Advanced Photon Source Injector Test Stand Control System

abstract:
  The Advanced Photon Source (APS) primary and backup injectors consist of two
thermionic-cathode rf guns. These guns are being upgraded to provide improved
performance, to improve ease of maintenance, and to reduce downtime required
for repair or replacement of a failed injector. As part of the process, an
injector test stand is being prepared. This stand is effectively independent of
the APS linac and will allow for complete characterization and validation of an
injector prior to its installation into the APS linac.
  A modular control system for the test stand has been developed using standard
APS control solutions with EPICS to deliver a flexible and comprehensive
control system. The modularity of the system will allow both future expansion
of test stand functionality and evaluation of new control techniques and
solutions.


title: An XML Driven Framework for Test Control and Data Analysis

abstract:
  An extensible, component-based framework has been developed at Fermilab to
promote software reuse and provide a common platform for developing a family of
test and data analysis systems. The framework allows for configuring
applications from components through the use of XML configurations. It can be
easily extended by adding new components and many application independent
components are already provided with the framework. The core of the system has
been developed in Java which guarantees its portability and facilitates the use
of object-oriented development technologies.


title:
Integrating Externally Developed Systems For SNS Linac Cooling And
  Vacuum

abstract:
  External contractors are developing the local cooling and vacuum control
systems for the Spallation Neutron Source (SNS) linac. Soon these systems will
be integrated into the facility-wide controls system. Allen-Bradley Logix5000
series programmable controllers, populated with appropriate input/output
modules, were selected as the local controllers. These controllers will be
interfaced to the facility-wide control system via VME systems with PowerPC
processors running the Wind River VxWorks operating system and Experimental
Physics and Industrial Control System (EPICS) front-end controller software.
This paper describes the interface and integration issues driven by project,
cooling system and vacuum system requirements and hardware selections.


title: The NIF Integrated Timing System - Design and Performance

abstract:
  The National Ignition Facility (NIF) will contain the world's most powerful
laser. NIF requires more than 1500 precisely timed trigger pulses to control
the timing of laser and diagnostic equipment. The Integrated Timing System
applies new concepts to generate and deliver triggers at preprogrammed times to
equipment throughout the laser and target areas of the facility. Trigger pulses
during the last 2 seconds of a shot cycle are required to have a jitter of less
than 20 ps (rms) and a wander of less than 100 ps (max). Also, the Timing
System allows simultaneous, independent use by multiple clients by partitioning
the system hardware into subsets that are controlled via independent software
keys. The hardware necessary to implement the Integrated Timing System is
commercially available. -- This work is performed under the auspices of the
U.S. Department of Energy by Lawrence Livermore National Laboratory under
contract No. W-7405-Eng-48.


title:
Readout and Control of a Power-recycled Interferometric
  Gravitational-wave Antenna

abstract:
  Interferometric gravitational wave antennas are based on Michelson
interferometers whose sensitivity to small differential length changes has been
enhanced by adding multiple coupled optical resonators. The use of optical
cavities is essential for reaching the required sensitivity, but sets
challenges for the control system which must maintain the cavities near
resonance. The goal for the strain sensitivity of the Laser Interferometer
Gravitational-wave Observatory (LIGO) is 10^-21 rms, integrated over a 100 Hz
bandwidth centered at 150 Hz. We present the major design features of the LIGO
length and frequency sensing and control system which will hold the
differential length to within 5 10^-14 m of the operating point. We also
highlight the restrictions imposed by couplings of noise into the gravitational
wave readout signal and the required immunity against them.


title:
Generating EPICS IOC Databases from a Relational Database - a Different
  Approach

abstract:
  The EPICS based control system of the ISAC radioactive beam facility uses the
CapFast schematic editor to construct the IOC function-block databases. This
allows a self-documenting graphical representation of the IOC software using a
hierarchical, object-like software structure with reusable components. On the
other hand, the control system is quarterbacked by a relational database, which
contains all device information. Using database reports and Perl scripts, a
device instantiation method was developed which generates top-level schematic
files in CapFast format. This method exploits the advantages of device data
entry and reporting using a relational database system while maintaining the
graphical representation of the IOC database.


title: Beam Diagnostics Systems For The National Ignition Facility

abstract:
  The National Ignition Facility laser focuses 1.8 Mega-joules of ultraviolet
light (wavelength 351 nano-meters) from 192 beams into a
600-micro-meter-diameter volume. Effective use of this output in target
experiments requires that the power output from all the beams match within 8%
over their entire 20-nanosecond waveform. The scope of NIF beam diagnostics
systems necessary to accomplish this task is unprecedented for laser
facilities. Each beam line contains 110 major optical components distributed
over a 510 meter path, and diagnostic tolerances for beam measurement are
demanding. Total laser pulse energy is measured with 2.8% precision, and the
inter-beam temporal variation of pulse power is measured with 4% precision.
These measurement goals are achieved through use of approximately 160 sensor
packages that measure the energy at five locations and power at 3 locations
along each beamline using 335 photodiodes, 215 calorimeters and 36 digitizers.
Successful operation of such a system requires a high level of automation of
the widely distributed sensors. Computer control systems provide the basis for
operating the shot diagnostics with repeatable accuracy, assisted by operators
who oversee system activities and setup, respond to performance exceptions, and
complete calibration and maintenance tasks.


title: Development of an Interpreter Program for an Equipment Control

abstract:
  A message oriented software scheme is used for the SPring-8 beamline control.
In the early stage, we developed customized control programs for each beamline.
As the number of beamlines increased, however, it became necessary to introduce
a general software scheme that cloud handle the control sequence for every
beamline. We developed a new server program, Command Interpreter (CI), as a
software framework. The CI interprets a high-level compound message issued from
client programs and decomposes it to a set of primitive control messages. The
message are sent to the VME computers afterwards. For flexibility, the
operation sequences specific to the individual baemline component are
standardized and defined in the interface definition files. Using the CI, the
response time overhead is reduced to 26% and the XAFS measurement time also
decreases by about 50%.


title:
Status and Controls Requirements of the Planned Heavy Ion Tumor Therapy
  Accelerator Facility HICAT

abstract:
  The HICAT project is a Heavy Ion accelerator for light ion Cancer Treatment
to be built for the clinics in Heidelberg, Germany. It consists of a 7 MeV/u
linac, a compact synchrotron and three treatment places, one of them equipped
with a 360 degree gantry beam-line. The facility will implement the intensity
controlled raster-scanning technique that was developed and successfully
demonstrated at GSI with over 100 patients at present. In order to produce the
beams with the characteristics requested by the treatment sequencer, the
accelerator must operate on a pulse-to-pulse basis with different settings.
This concept imposes strict and challenging demands on the operation of the
accelerators and hence the control system of the facility. The control system
should be developed, installed and maintained by and under the complete
responsibility of an industrial system provider, using a state-of-the-art
system and wide-spread industrial components wherever possible. The
presentation covers the status of the project and the requirements on the
control system.


title: On Stability of Physics Systems

abstract:
  Within the framework of the hypothesis offered by authors about a
complex-valued nature of physical quantities the stability of basic equations
of the classical physics concerning complex-valued perturbations of parameters
and boundary conditions is explored. The conducted examination of nonlinear
equations and, what is more important, of linear differential equations shows
violation in some cases of the continuous dependence of the solution on the
change of imaginary parts of parameters and boundary conditions in the
neighborhood of zero. In other words, it was revealed that a small imaginary
part may drive the real solution. It may be concluded that a small imaginary
part, even if unobservable, is still an inherent characteristic of a physical
quantity, being yet something like a hidden parameter, and manifests itself
only indirectly forcing the system to move in this or that direction, which may
be taken as a basis for experimental testing of the put forward hypothesis
about a complex-valued nature of physical quantities.


title:
A Study of a Real-Time Operating System on the Intel-Based Vme
  Controllers

abstract:
  In this paper, we described the performance differences between VME-based
controllers, HP743rt/HP-RT and IA-based platforms. We measured some kind of
real-time benchmarks and discussed a relation of architecture dependences.


title:
Implementation of JFPC (Java for Process Control) under Linux - a
  mechanism to access industrial I/Os in a JAVA/Linux environment

abstract:
  Using JAVA for process control requires the access to I/O-Hardware. This
problem is addressed in several ongoing standardisation efforts for Real Time
Java. A spin-off of these standardisation efforts is the Siemens product JFPC
(Java for Process Control), which is based on the ideas of OPC (OLE for Process
Control). It is available under the proprietary RT kernel RMOS and under
Windows NT. Based on a contract with Siemens, ZEL - the central electronics
facility of Forschungszentrum Juelich - has implemented JFPC under Linux.
Additionally, several JFPC providers, e.g for accessing industrial components
via PROFIBUS DP have been implemented.


title:
Data Acquisition and Uesr Interface of Beam Instrumentation System at
  SRRC

abstract:
  Data acquisition systems for the accelerator complex at SRRC composed various
hardware and software components. Beam signals are processed by related
processing electronics, and connect to control system by various type of
interfaces in data acquisition front-end. These front-end include VME crates,
personal computers and instruments bus adapters. Fast Ethernet connected all
elements together with control consoles. User interface is running on control
console. Real-time data capture; display and alaysis are supported on control
console. Analysis tools based on Matlab scripts are adopted. Hardware and
software implementation of the system will be presented. User interface
supports are also described.


title: Converting Equipment Control Software from Pascal to C/C++

abstract:
  The equipment control (EC) software of the GSI accelerators has been written
entirely in Pascal. Modern software development is based on C++ or Java. To be
prepared for the future, we decided to convert the EC software from Pascal to C
in a first step. Considering the large amount of software, this is done
automatically as far as possible. The paper describes our experiences gained
using a Pascal to C translator, Perl scripts, and, of course, some manual
interaction.