title: Hadron interactions from lattice QCD

abstract:
  Studies on hadron interactions from lattice QCD are reviewed. The $S$-wave
$\pi\pi$ scattering lengths of the I=0 and I=2 channels are extracted from
various lattice determinations of low energy constants in $N_f=2$ chiral
perturbation theory. The results agree with each other and agree also with
other non-lattice estimates. Recently the $P$-wave $\pi\pi$ scattering phase
shift for the I=1 channel has been calculated. A preliminary estimate of the
$\rho$ meson decay width from the phase shift is consistent with the
experimental value. Two approaches to potentials between hadrons are discussed.
One is a method using static quarks to define the distance between two hadrons.
The other is a method to define a potential from a wave function of two
hadrons. An application of the latter to the nucleon-nucleon ($NN$) potential
turns out to reproduce qualitative features of the phenomenological $NN$
potential such as attraction at long distance and repulsion at short distance.
Theoretical issues of this approach are also discussed.


title:
$KK$-theory spectra for $C^\ast$-categories and discrete groupoid
  $C^\ast$-algebras

abstract:
  In this paper we refine a version of bivariant $K$-theory developed by Cuntz
to define symmetric spectra representing the $KK$-theory of $C^\ast$-categories
and discrete groupoid $C^\ast$-algebras. In both cases, the Kasparov product
can be expressed as a smash product of spectra.


title: Gas rich galaxies from the FIGGS survey

abstract:
  The FIGGS (Faint Irregular Galaxy GMRT Survey) is aimed at creating a
multi-wavelength observational data base for a volume limited sample of the
faintest gas rich galaxies. In this paper we discuss two very gas rich galaxies
that were observed as part of the FIGGS survey, viz. NGC 3741 and And IV. These
galaxies are unusual in that they have extremely extended gas disks and very
high ratios of dark to luminous matter. The very extended HI disks provide an
unique opportunity to trace the extended distribution of dark matter around
faint galaxies. We compare the baryon fraction of these galaxies with a sample
of galaxies with well measured rotation curves and discuss whether extremely
gas rich dwarf galaxies have abnormally small baryon fractions.


title: Hot Cores in the submm - obscured by dust?

abstract:
  We present APEX observations of HCN (9-8) and (4-3) lines toward a sample of
hot cores. The spectral shapes of the main transitions are asymmetric and
self-absorbed, as expected for high optical depth in a possibly infalling
envelope. For spherical symmetry, the large column densities of these sources
would mean that the central region is obscured by dust above a certain
frequency. However, we detected the vibrationally excited satellite lines
(v_2=1; J=9-8) at 797 GHz, which originate from the inner regions. This
indicates that high-frequency ALMA observations of hot core centers will be
feasible.


title: Guarded Hybrid Knowledge Bases

abstract:
  Recently, there has been a lot of interest in the integration of Description
Logics and rules on the Semantic Web.We define guarded hybrid knowledge bases
(or g-hybrid knowledge bases) as knowledge bases that consist of a Description
Logic knowledge base and a guarded logic program, similar to the DL+log
knowledge bases from (Rosati 2006). G-hybrid knowledge bases enable an
integration of Description Logics and Logic Programming where, unlike in other
approaches, variables in the rules of a guarded program do not need to appear
in positive non-DL atoms of the body, i.e. DL atoms can act as guards as well.
Decidability of satisfiability checking of g-hybrid knowledge bases is shown
for the particular DL DLRO, which is close to OWL DL, by a reduction to guarded
programs under the open answer set semantics. Moreover, we show
2-EXPTIME-completeness for satisfiability checking of such g-hybrid knowledge
bases. Finally, we discuss advantages and disadvantages of our approach
compared with DL+log knowledge bases.


title:
Simple Stellar Population Models as probed by the Large Magellanic Cloud
  Star Cluster ESO 121-SC03

abstract:
  The presence of blue straggler stars (BSs) in star clusters has proven a
challenge to conventional simple stellar population (SSP) models. Conventional
SSP models are based on the evolution theory of single stars. Meanwhile, the
typical locations of BSs in the colour-magnitude diagram of a cluster are
brighter and bluer than the main sequence turn-off point. Such loci cannot be
predicted by single-star evolution theory. However, stars with such properties
contribute significantly to the integrated light of the cluster. In this paper,
we reconstruct the integrated properties of the Large Magellanic Cloud cluster
ESO 121-SC03, based on a detailed exploration of the individual cluster stars,
and with particular emphasis on the cluster's BSs. We find that the integrated
light properties of ESO 121-SC03 are dramatically modified by its BS component.
The integrated spectral energy distribution (ISED) flux level is significantly
enhanced toward shorter wavelengths, and all broad-band colours become bluer.
When fitting the fully integrated ISED of this cluster based on conventional
SSP models, the best-fitting values of age and metallicity are significantly
underestimated compared to the true cluster parameters. The age underestimate
is $\sim40$ per cent if we only include the BSs within the cluster's half-light
radius and $\sim60$ per cent if all BSs are included. The corresponding
underestimates of the cluster's metallicity are $\sim30$ and $\sim60$ per cent,
respectively. The populous star clusters in the Magellanic Clouds are ideal
objects to explore the potential importance of BSs for the integrated light
properties of more distant unresolved star clusters in a statistically robust
manner, since they cover a large range in age and metallicity.


title: On Approximating Multi-Criteria TSP

abstract:
  We present approximation algorithms for almost all variants of the
multi-criteria traveling salesman problem (TSP).
  First, we devise randomized approximation algorithms for multi-criteria
maximum traveling salesman problems (Max-TSP). For multi-criteria Max-STSP,
where the edge weights have to be symmetric, we devise an algorithm with an
approximation ratio of 2/3 - eps. For multi-criteria Max-ATSP, where the edge
weights may be asymmetric, we present an algorithm with a ratio of 1/2 - eps.
Our algorithms work for any fixed number k of objectives. Furthermore, we
present a deterministic algorithm for bi-criteria Max-STSP that achieves an
approximation ratio of 7/27.
  Finally, we present a randomized approximation algorithm for the asymmetric
multi-criteria minimum TSP with triangle inequality Min-ATSP. This algorithm
achieves a ratio of log n + eps.


title:
Discrete spectrum distribution of the Landau Operator Perturbed by an
  Expanding Electric Potential

abstract:
  Under a perturbation by a decaying electric potential, the Landau Hamiltonian
acquires some discrete eigenvalues between the Landau levels. We study the
perturbation by an "expanding" electric potential $V(t^{-1}x)$, $t>0$, and
derive a quasi-classical formula for the counting function of the discrete
spectrum as $t\to \infty$.


title:
Fundamental interactions in quantum phase space specified by extra
  dimensional constants

abstract:
  A generalized algebra of quantum observables, depending on extra dimensional
constants, is considered. Some limiting forms of the algebra are investigated
and their possible applications to the descriptions of interactions of
fundamental particles are proposed. A relation between current and constituent
quark masses is found using a modified quark equation of Dirac-Gursey-Lee type
and restrictions on the results of simultaneous measurements of momentum
components are pointed out.


title:
Three-Dimensional Bulk Electronic Structures of Ca1.5Sr0.5RuO4 Studied
  by Soft X-ray Angle-Resolved Photoemission

abstract:
  We report on experimental data of the three-dimensional bulk Fermi surfaces
of the layered strongly correlated Ca1.5Sr0.5RuO4 system. The measurements have
been performed by means of hn-depndent bulk-sensitive soft x-ray angle-resolved
photoemission technique. Our experimental data evinces the bulk Fermi surface
topology at kz~0 to be qualitatively different from the one observed by
surface-sensitive low-energy ARPES. Furthermore, stronger kz dispersion of the
circle-like gamma Fermi surface sheet is observed compared with Sr2RuO4. Thus
in the paramagnetic metal phase, Ca1.5Sr0.5RuO4 compound is found to have
rather three-dimensional electronic structure.


title:
Intrinsic atomic scale modulations of the superconducting gap of
  2H-NbSe2

abstract:
  We present scanning tunneling microscopy and spectroscopy measurements at
100mK in the superconducting material 2H-NbSe2 that show well defined features
in the superconducting density of states changing in a pattern closely
following atomic periodicity. Our experiment demonstrates that the intrinsic
superconducting density of states can show atomic size modulations, which
reflect the reciprocal space structure of the superconducting gap. In
particular we obtain that the superconducting gap of 2H-NbSe2 has six fold
modulated components at 0.75 mV and 1.2 mV.Moreover, we also find related
atomic size modulations inside vortices, demonstrating that the much discussed
star shape vortex structure produced by localized states inside the vortex
cores, has a, hitherto undetected, superposed atomic size modulation. The tip
substrate interaction in an anisotropic superconductor has been calculated,
giving position dependent changes related to the observed gap anisotropy.


title: Mean-field backward stochastic differential equations: A limit approach

abstract:
  Mathematical mean-field approaches play an important role in different fields
of Physics and Chemistry, but have found in recent works also their application
in Economics, Finance and Game Theory. The objective of our paper is to
investigate a special mean-field problem in a purely stochastic approach: for
the solution $(Y,Z)$ of a mean-field backward stochastic differential equation
driven by a forward stochastic differential of McKean--Vlasov type with
solution $X$ we study a special approximation by the solution $(X^N,Y^N,Z^N)$
of some decoupled forward--backward equation which coefficients are governed by
$N$ independent copies of $(X^N,Y^N,Z^N)$. We show that the convergence speed
of this approximation is of order $1/\sqrt{N}$. Moreover, our special choice of
the approximation allows to characterize the limit behavior of
$\sqrt{N}(X^N-X,Y^N-Y,Z^N-Z)$. We prove that this triplet converges in law to
the solution of some forward--backward stochastic differential equation of
mean-field type, which is not only governed by a Brownian motion but also by an
independent Gaussian field.


title:
Predicting spectral features in galaxy spectra from broad-band
  photometry

abstract:
  We explore the prospects of predicting emission line features present in
galaxy spectra given broad-band photometry alone. There is a general consent
that colours, and spectral features, most notably the 4000 A break, can predict
many properties of galaxies, including star formation rates and hence they
could infer some of the line properties. We argue that these techniques have
great prospects in helping us understand line emission in extragalactic objects
and might speed up future galaxy redshift surveys if they are to target
emission line objects only. We use two independent methods, Artifical Neural
Neworks (based on the ANNz code) and Locally Weighted Regression (LWR), to
retrieve correlations present in the colour N-dimensional space and to predict
the equivalent widths present in the corresponding spectra. We also investigate
how well it is possible to separate galaxies with and without lines from broad
band photometry only. We find, unsurprisingly, that recombination lines can be
well predicted by galaxy colours. However, among collisional lines some can and
some cannot be predicted well from galaxy colours alone, without any further
redshift information. We also use our techniques to estimate how much
information contained in spectral diagnostic diagrams can be recovered from
broad-band photometry alone. We find that it is possible to classify AGN and
star formation objects relatively well using colours only. We suggest that this
technique could be used to considerably improve redshift surveys such as the
upcoming FMOS survey and the planned WFMOS survey.


title:
Elliptic systems of pseudodifferential equations in a refined scale on a
  closed manifold

abstract:
  We study a system of pseudodifferential equations that is elliptic in the
sense of Petrovskii on a closed compact smooth manifold. We prove that the
operator generated by the system is Fredholm one on a refined two-sided scale
of the functional Hilbert spaces. Elements of this scale are the special
isotropic spaces of H\"{o}rmander--Volevich--Paneah.


title: The effect of the topology on the spatial ultimatum game

abstract:
  In this work we present an analysis of a spatially non homogeneous ultimatum
game. By considering different underlying topologies as substrates on top of
which the game takes place we obtain nontrivial behaviors for the evolution of
the strategies of the players. We analyze separately the effect of the size of
the neighborhood and the spatial structure. Whereas this last effect is the
most significant one, we show that even for disordered networks and provided
the neighborhood of each site is small, the results can be significantly
different from those obtained in the case of fully connected networks.


title: On the solar abundance of indium

abstract:
  The generally adopted value for the solar abundance of indium is over six
times higher than the meteoritic value. We address this discrepancy through
numerical synthesis of the 451.13 nm line on which all indium abundance studies
are based, both for the quiet-sun and the sunspot umbra spectrum, employing
standard atmosphere models and accounting for hyperfine structure and Zeeman
splitting in detail. The results, as well as a re-appraisal of indium
nucleosynthesis, suggest that the solar indium abundance is close to the
meteoritic value, and that some unidentified ion line causes the 451.13 nm
feature in the quiet-sun spectrum.


title:
Mean-Field Backward Stochastic Differential Equations and Related
  Partial Differential Equations

abstract:
  In [5] the authors obtained Mean-Field backward stochastic differential
equations (BSDE) associated with a Mean-field stochastic differential equation
(SDE) in a natural way as limit of some highly dimensional system of forward
and backward SDEs, corresponding to a large number of ``particles'' (or
``agents''). The objective of the present paper is to deepen the investigation
of such Mean-Field BSDEs by studying them in a more general framework, with
general driver, and to discuss comparison results for them. In a second step we
are interested in partial differential equations (PDE) whose solutions can be
stochastically interpreted in terms of Mean-Field BSDEs. For this we study a
Mean-Field BSDE in a Markovian framework, associated with a Mean-Field forward
equation. By combining classical BSDE methods, in particular that of ``backward
semigroups" introduced by Peng [14], with specific arguments for Mean-Field
BSDEs we prove that this Mean-Field BSDE describes the viscosity solution of a
nonlocal PDE. The uniqueness of this viscosity solution is obtained for the
space of continuous functions with polynomial growth. With the help of an
example it is shown that for the nonlocal PDEs associated to Mean-Field BSDEs
one cannot expect to have uniqueness in a larger space of continuous functions.


title: Zero-bias conductance in carbon nanotube quantum dots

abstract:
  We present numerical renormalization group calculations for the zero-bias
conductance of quantum dots made from semiconducting carbon nanotubes. These
explain and reproduce the thermal evolution of the conductance for different
groups of orbitals, as the dot-lead tunnel coupling is varied and the system
evolves from correlated Kondo behavior to more weakly correlated regimes. For
integer fillings $N=1,2,3$ of an SU(4) model, we find universal scaling
behavior of the conductance that is distinct from the standard SU(2) universal
conductance, and concurs quantitatively with experiment. Our results also agree
qualitatively with experimental differential conductance maps.


title: The Key Renewal Theorem for a Transient Markov Chain

abstract:
  We consider a time-homogeneous Markov chain $X_n$, $n\ge0$, valued in ${\bf
R}$. Suppose that this chain is transient, that is, $X_n$ generates a
$\sigma$-finite renewal measure. We prove the key renewal theorem under
condition that this chain has asymptotically homogeneous at infinity jumps and
asymptotically positive drift.


title:
Summary of GR18 Numerical Relativity parallel sessions (B1/B2 and B2),
  Sydney, 8-13 July 2007

abstract:
  The numerical relativity session at GR18 was dominated by physics results on
binary black hole mergers. Several groups can now simulate these from a time
when the post-Newtonian equations of motion are still applicable, through
several orbits and the merger to the ringdown phase, obtaining plausible
gravitational waves at infinity, and showing some evidence of convergence with
resolution. The results of different groups roughly agree. This new-won
confidence has been used by these groups to begin mapping out the
(finite-dimensional) initial data space of the problem, with a particular focus
on the effect of black hole spins, and the acceleration by gravitational wave
recoil to hundreds of km/s of the final merged black hole. Other work was
presented on a variety of topics, such as evolutions with matter, extreme mass
ratio inspirals, and technical issues such as gauge choices.


title: The Bologna Open Clusters Chemical Evolution project (in short: BOCCE)

abstract:
  I present here our project, the Bologna Open Clusters Chemical Evolution
(BOCCE) project, aimed at using Open Clusters as tracers of the disk properties
and their evolution with time. We are collecting and homogeneously analyzing
data, both photometric and spectroscopic, on a large sample of open clusters,
representative of the old cluster population, and I show here results obtained
on a subset of our clusters.


title: Finite Element simulation of radiation losses in photonic crystal fibers

abstract:
  In our work we focus on the accurate computation of light propagation in
finite size photonic crystal structures with the finite element method (FEM).
We discuss how we utilize numerical concepts like high-order finite elements,
transparent boundary conditions and goal-oriented error estimators for adaptive
grid refinement in order to compute radiation leakage in photonic crystal
fibers and waveguides. Due to the fast convergence of our method we can use it
e.g. to optimize the design of photonic crystal structures with respect to
geometrical parameters, to minimize radiation losses and to compute
attenutation spectra for different geometries.


title: Statistical ensemble equivalence problem

abstract:
  A problem of the equivalence of statistical ensembles is critically analyzed.
It is shown, that although different probability distributions of statistical
physics have the same behavior in the thermodynamic limit, there are physical
observables -- semi-intensive variables -- which keep memory of the underlying
ensembles. This property is an universal one and can be observed even in the
simplest case of the grand canonical and canonical ensembles of the classical
statistical physics.


title: Distribution Amplitudes of Vector Mesons

abstract:
  Results are presented for the lowest moment of the distribution amplitude for
the K-star vector meson. Both longitudinal and transverse moments are
investigated. We use two flavours of O(a) improved Wilson fermions, together
with a non-perturbative renormalisation of the matrix element.


title:
Transition in pipe flow: the saddle structure on the boundary of
  turbulence

abstract:
  The laminar-turbulent boundary S is the set separating initial conditions
which relaminarise uneventfully from those which become turbulent. Phase space
trajectories on this hypersurface in cylindrical pipe flow look to be chaotic
and show recurring evidence of coherent structures. A general numerical
technique is developed for recognising approaches to these structures and then
for identifying the exact coherent solutions themselves. Numerical evidence is
presented which suggests that trajectories on S are organised around only a few
travelling waves and their heteroclinic connections. If the flow is suitably
constrained to a subspace with a discrete rotational symmetry, it is possible
to find locally-attracting travelling waves embedded within S. Four new types
of travelling waves were found using this approach.


title: Modelling Complex Networks: Cameo Graphs And Transport Processes

abstract:
  We discuss a model accounting for the creation and development of transport
networks based on the Cameo principle which refers to the idea of distribution
of resources, including land, water, minerals, fuel and wealth. We also give an
outlook of the use of random walks as an effective tool for the investigation
of network structures and its functional segmentation. In particular, we have
studied the complex transport network of Venetian canals by means of random
walks.


title:
Emergent singular solutions of non-local density-magnetization equations
  in one dimension

abstract:
  We investigate the emergence of singular solutions in a non-local model for a
magnetic system. We study a modified Gilbert-type equation for the
magnetization vector and find that the evolution depends strongly on the length
scales of the non-local effects. We pass to a coupled density-magnetization
model and perform a linear stability analysis, noting the effect of the length
scales of non-locality on the system's stability properties. We carry out
numerical simulations of the coupled system and find that singular solutions
emerge from smooth initial data. The singular solutions represent a collection
of interacting particles (clumpons). By restricting ourselves to the
two-clumpon case, we are reduced to a two-dimensional dynamical system that is
readily analyzed, and thus we classify the different clumpon interactions
possible.


title:
Angular Power Spectrum Estimation using High Performance Reconfigurable
  Computing

abstract:
  Angular power spectra are an important measure of the angular clustering of a
given distribution. In Cosmology, they are applied to such vastly different
observations as galaxy surveys that cover a fraction of the sky and the Cosmic
Microwave Background that covers the entire sky, to obtain fundamental
parameters that determine the structure and evolution of the universe. The
calculation of an angular power spectrum, however, is complex and the
optimization of these calculations is a necessary consideration for current and
forthcoming observational surveys. In this work, we present preliminary results
of implementing angular power spectrum estimation scheme on a high-performance
reconfigurable computing platform.


title: Studies in the physics of evolution: creation, formation, destruction

abstract:
  The concept of (auto)catalytic systems has become a cornerstone in
understanding evolutionary processes in various fields. The common ground is
the observation that for the production of new species/goods/ideas/elements
etc. the pre-existence of specific other elements is a necessary condition. In
previous work some of us showed that the dynamics of the catalytic network
equation can be understood in terms of topological recurrence relations paving
a path towards the analytic tractability of notoriously high dimensional
evolution equations. We apply this philosophy to studies in socio-physics,
bio-diversity and massive events of creation and destruction in technological
and biological networks. Cascading events, triggered by small exogenous
fluctuations, lead to dynamics strongly resembling the qualitative picture of
Schumpeterian economic evolution. Further we show that this new methodology
allows to mathematically treat a variant of the threshold voter-model of
opinion formation on networks. For fixed topology we find distinct phases of
mixed opinions and consensus.


title:
Structural parameters for globular clusters in NGC 5128. III. ACS
  surface-brightness profiles and model fits

abstract:
  We present internal surface-brightness profiles, based on HST/ACS imaging in
the F606W bandpass, for 131 globular cluster (GC) candidates with luminosities
10^4 - 3 x 10^6 solar, in the giant elliptical galaxy NGC 5128. Several
structural models are fit to the profile of each cluster and combined with
mass-to-light ratios from population-synthesis models, to derive a catalogue of
fundamental structural and dynamical parameters parallel in form to the
catalogues recently produced by McLaughlin & van der Marel and Barmby et al.
for GCs and massive young star clusters in Local Group galaxies. As part of
this, we provide corrected and extended parameter estimates for another 18
clusters in NGC 5128, which we observed previously. We show that, like GCs in
the Milky Way and some of its satellites, the majority of globulars in NGC 5128
are well fit by isotropic Wilson models, which have intrinsically more
distended envelope structures than the standard King lowered isothermal
spheres. We use our models to predict internal velocity dispersions for every
cluster in our sample. These predictions agree well in general with the
observed dispersions in a small number of clusters for which spectroscopic data
are available. In a subsequent paper, we use these results to investigate
scaling relations for GCs in NGC 5128.


title: The $KH$-Isomorphism Conjecture and Algebraic $KK$-theory

abstract:
  In this article we prove that the $KH$-asembly map, as defined by Bartels and
L{\"u}ck, can be described in terms of the algebraic $KK$-theory of Cortinas
and Thom. The $KK$-theory description of the $KH$-assembly map is similar to
that of the Baum-Connes assembly map. In very elementary cases, methods used to
prove the Baum-Connes conjecture also apply to the $KH$-isomorphism conjecture.


title:
Algebraic $K$-theory Spectra and Factorisations of Analytic Assembly
  Maps

abstract:
  In this article we use existing machinery to define connective $K$-theory
spectra associated to topological ringoids. Algebraic $K$-theory of discrete
ringoids, and the analytic $K$-theory of Banach categories are obtained as
special cases.
  As an application, we show how the analytic assembly maps featuring in the
Novikov and Baum-Connes conjectures can be factorised into composites of
assembly maps resembling those appearing in algebraic $K$-theory and maps
coming from completions of certain topological ringoids into Banach categories.
These factorisations are proved by using existing characterisations of assembly
maps along with our unified picture of algebraic and analytic $K$-theory.


title: Potts-Percolation-Gauss Model of a Solid

abstract:
  We study a statistical mechanics model of a solid. Neighboring atoms are
connected by Hookian springs. If the energy is larger than a threshold the
"spring" is more likely to fail, while if the energy is lower than the
threshold the spring is more likely to be alive. The phase diagram and
thermodynamic quantities, such as free energy, numbers of bonds and clusters,
and their fluctuations, are determined using renormalization-group and
Monte-Carlo techniques.


title:
Some numerical studies of the evolution of generalized parton
  distributions

abstract:
  We study the evolution behavior of generalized parton distributions at small
longitudinal momentum fraction. Particular attention is paid to the ratio of a
generalized parton distribution and its forward limit, to the mixing between
quarks and gluons, and to the dependence on the squared momentum transfer t.


title:
Exact finite approximations of average-cost countable Markov Decision
  Processes

abstract:
  For a countable-state Markov decision process we introduce an embedding which
produces a finite-state Markov decision process. The finite-state embedded
process has the same optimal cost, and moreover, it has the same dynamics as
the original process when restricting to the approximating set. The embedded
process can be used as an approximation which, being finite, is more convenient
for computation and implementation.


title: The defect of Fano 3-folds

abstract:
  This paper studies the defect of terminal Gorenstein Fano 3 folds. I
determine a bound on the defect of terminal Gorenstein Fano 3-folds of Picard
rank 1 that do not contain a plane. I give a general bound for quartic 3-folds
and indicate how to study the defect of terminal Gorenstein Fano 3-folds with
Picard rank 1 that contain a plane.


title: On Perturbations of Quintom Bounce

abstract:
  A Quintom universe with an equation-of-state crossing the cosmological
constant boundary can provide a bouncing solution dubbed the Quintom Bounce and
thus resolve the Big Bang singularity. In this paper, we investigate the
cosmological perturbations of the Quintom Bounce both analytically and
numerically. We find that the fluctuations in the dominant mode in the
post-bounce expanding phase couple to the growing mode of the perturbations in
the pre-bounce contracting phase.


title:
Efficient routing in heavy traffic under partial sampling of service
  times

abstract:
  We consider a queue with renewal arrivals and n exponential servers in the
Halfin-Whitt heavy traffic regime, where n and the arrival rate increase
without bound, so that a critical loading condition holds. Server k serves at
rate $\mu_k $, and the empirical distribution of the $\mu_k $ is assumed to
converge weakly. We show that very little information on the service rates is
required for a routing mechanism to perform well. More precisely, we construct
a routing mechanism that has access to a single sample from the service time
distribution of each of $n$ to the power of $1/2 + \epsilon $ randomly selected
servers, but not to the actual values of the service rates, the performance of
which is asymptotically as good as the best among mechanisms that have the
complete information on $ \mu_k $.


title: Search for Lepton Flavor Violating tau Decays into Three Leptons

abstract:
  We search for lepton-flavor-violating tau decays into three leptons (electron
or muon) using 535 fb-1 of data collected with the Belle detector at the KEKB
asymmetric-energy e+e- collider. No evidence for these decays is observed, and
we set 90% confidence level upper limits on the branching fractions of
(2.0-4.1)x10^-8. These results improve upon our previously published upper
limits by factors of 4.9 to 10.


title: Integer operators in finite von Neumann algebras

abstract:
  Motivated by the study of spectral properties of self-adjoint operators in
the integral group ring of a sofic group, we define and study integer
operators. We establish a relation with classical potential theory and in
particular the circle of results obtained by M. Fekete and G. Szeg"o. More
concretely, we use results by R. Rumely on equidistribution of algebraic
integers to obtain a description of those integer operator which have spectrum
of logarithmic capacity less or equal to one.
  Finally, we relate the study of integer operators to a recent construction by
B. and L. Petracovici and A. Zaharescu.


title:
Uniqueness of a constrained variational problem and large deviations of
  buffer size

abstract:
  We show global uniqueness of the solution to a class of constrained
variational problems, using scaling properties. This is used to establish the
essential uniqueness of solutions of a large deviations problem in multiple
dimensions. The result is motivated by models of buffers, and in particular the
probability of, and typical path to overflow in the limit of small buffers,
which we analyze.


title:
Coagulation, fragmentation and radial motion of solid particles in
  protoplanetary disks

abstract:
  The growth of solid particles towards meter sizes in protoplanetary disks has
to circumvent at least two hurdles, namely the rapid loss of material due to
radial drift and particle fragmentation due to destructive collisions. In this
paper, we present the results of numerical simulations with more and more
realistic physics involved. Step by step, we include various effects, such as
particle growth, radial/vertical particle motion and dust particle
fragmentation in our simulations. We demonstrate that the initial dust-to-gas
ratio is essential for the particles to overcome the radial drift barrier. If
this value is increased by a factor of 2 compared with the canonical value for
the interstellar medium, km-sized bodies can form in the inner disk <2 AU
within 10 thousand years. However, we find that solid particles get destroyed
through collisional fragmentation. Only with the unrealistically high-threshold
velocities needed for fragmentation to occur (>30 m/s), particles are able to
grow to larger sizes in low turbulent disks. We also find that less than 5% of
the small dust grains remain in the disk after 1 Myrs due to radial drift, no
matter whether fragmentation is included in the simulations or not. In this
paper, we also present considerable improvements to existing algorithms for
dust-particle coagulation, which speed up the coagulation scheme by a factor of
10 thousand.


title: Dynamical Coupled-Channels Analysis at EBAC

abstract:
  The status of dynamical coupled-channel analysis at Excited Baryon Analysis
Center (EBAC) of Jefferson Laboratory is reported.


title: Operator Product Expansion of Wilson surfaces from M5-branes

abstract:
  The operator product expansion (OPE) of the Wilson surface operators in
six-dimensional (2, 0) superconformal field theory is studied from AdS/CFT
correspondence in this paper. We compute the OPE coefficients of the chiral
primary operators using the M5-brane description for spherical Wilson surface
operators in higher dimensional representations. We use the non-chiral M5-brane
action in our calculation. We also discuss their membrane limit, and compare
our results with the ones obtained from membrane description.


title: Cyclic coverings, Calabi-Yau manifolds and Complex multiplication

abstract:
  We construct families of Calabi-Yau manifolds with dense set of complex
multiplication fibers in an arbitrary dimension. We will also give explicite
examples of complex multiplication fibers. For this construction we use
families of curves with dense set of complex multiplication fibers. In
addition, we give examples of such families for each genus less or equal 7 and
we study the generic Hodge groups of families of cyclic covers of the
projective line.


title:
Baryon scattering at high energies: wave function, impact factor, and
  gluon radiation

abstract:
  The scattering of a baryon consisting of three massive quarks is investigated
in the high energy limit of perturbative QCD. A model of a relativistic
proton-like wave function, dependent on valence quark longitudinal and
transverse momenta and on quark helicities, is proposed, and we derive the
baryon impact factors for two, three and four t-channel gluons. We find that
the baryonic impact factor can be written as a sum of three pieces: in the
first one a subsystem consisting of two of the three quarks behaves very much
like the quark-antiquark pair in gamma* scattering, whereas the third quark
acts as a spectator. The second term belongs to the odderon, whereas in the
third (C-even) piece all three quarks participate in the scattering. This term
is new and has no analogue in gamma* scattering. We also study the small x
evolution of gluon radiation for each of these three terms. The first term
follows the same pattern of gluon radiation as the gamma*-initiated
quark-antiquark dipole, and, in particular, it contains the BFKL evolution
followed by the 2-->4 transition vertex (triple Pomeron vertex). The
odderon-term is described by the standard BKP evolution, and the baryon couples
to both known odderon solutions, the Janik-Wosiek solution and the BLV
solution. Finally, the t-channel evolution of the third term starts with a
three reggeized gluon state which then, via a new 3-->4 transition vertex,
couples to the four gluon (two-Pomeron) state. We briefly discuss a few
consequences of these findings, in particular the pattern of unitarization of
high energy baryon scattering amplitudes.


title:
Nonequilibrium Phase Transitions into Absorbing States: Focused around
  the pair contact process with diffusion

abstract:
  Systems with absorbing (trapped) states may exhibit a nonequilibrium phase
transition from a noise-free inactive phase into an ever-lasting active phase.
We briefly review the absorbing critical phenomena and universality classes,
and discuss over the controversial issues on the pair contact process with
diffusion (PCPD). Two different approaches are proposed to clarify its
universality issue, which unveil strong evidences that the PCPD belongs to a
new universality class other than the directed percolation class.


title:
Stability, Singularities and Mass Thresholds in Child Universe
  Production: a concise survey including some recent results and prospects

abstract:
  We present a review of selected topics concerning the creation and evolution
of child universes, together with a concise account of some recent progress in
the field.


title: The Lyman-alpha Emission Line as a Cosmological Tool

abstract:
  This thesis deals with different aspects of a special kind of high redshift
galaxy, namely Ly-alpha emitters. Ly-alpha emitters are galaxies found through
their Ly-alpha emission, at redshifts larger than z >~ 2 where the emission
line has been redshifted into the optical or near-infrared regime. The thesis
has two main parts; a lower redshift, observational part (z ~ 3) and a more
technical/theoretical very high redshift part (z ~ 9).
  In the first, lower redshift part I present the analysis of a narrow-band
image taken in the GOODS-S field, focused on a redshift for Ly-alpha of z =
3.15. The image, covering a central part of the GOODS-S field revealed 25
Ly-alpha emitting candidates, of which one turned out to be a so-called
Ly-alpha blob. In the second part, I discuss future, very high redshift
narrow-band surveys for Ly-alpha emitters. Finally, in a project unrelated to
the other two parts of the thesis, I present a search for a 'Fundamental plane'
of Ly-alpha emitters in the colour space produced by large-scale
multi-wavelength surveys such as GOODS or COSMOS. [Abridged]


title: Topos-Theoretic Extension of a Modal Interpretation of Quantum Mechanics

abstract:
  This paper deals with topos-theoretic truth-value valuations of quantum
propositions. Concretely, a mathematical framework of a specific type of modal
approach is extended to the topos theory, and further, structures of the
obtained truth-value valuations are investigated. What is taken up is the modal
approach based on a determinate lattice $\Dcal(e,R)$, which is a sublattice of
the lattice $\Lcal$ of all quantum propositions and is determined by a quantum
state $e$ and a preferred determinate observable $R$. Topos-theoretic extension
is made in the functor category $\Sets^{\CcalR}$ of which base category
$\CcalR$ is determined by $R$. Each true atom, which determines truth values,
true or false, of all propositions in $\Dcal(e,R)$, generates also a
multi-valued valuation function of which domain and range are $\Lcal$ and a
Heyting algebra given by the subobject classifier in $\Sets^{\CcalR}$,
respectively. All true propositions in $\Dcal(e,R)$ are assigned the top
element of the Heyting algebra by the valuation function. False propositions
including the null proposition are, however, assigned values larger than the
bottom element. This defect can be removed by use of a subobject
semi-classifier. Furthermore, in order to treat all possible determinate
observables in a unified framework, another valuations are constructed in the
functor category $\Sets^{\Ccal}$. Here, the base category $\Ccal$ includes all
$\CcalR$'s as subcategories. Although $\Sets^{\Ccal}$ has a structure
apparently different from $\Sets^{\CcalR}$, a subobject semi-classifier of
$\Sets^{\Ccal}$ gives valuations completely equivalent to those in
$\Sets^{\CcalR}$'s.


title: On Geometro-thermodynamics of Dilaton Black Holes

abstract:
  In this talk we present the latest results from our ongoing project on
geometro-thermodynamics (also known as information geometry of thermodynamics
or Ruppeiner geometry) of dilaton BHs in 4D in both Einstein and string frames
and a dyonic dilaton BH and at the end we report very briefly results from this
approach to the 2D dilaton BHs.


title: Supercritical biharmonic equations with power-type nonlinearity

abstract:
  The biharmonic supercritical equation $\Delta^2u=|u|^{p-1}u$, where $n>4$ and
$p>(n+4)/(n-4)$, is studied in the whole space $\mathbb{R}^n$ as well as in a
modified form with $\lambda(1+u)^p$ as right-hand-side with an additional
eigenvalue parameter $\lambda>0$ in the unit ball, in the latter case together
with Dirichlet boundary conditions. As for entire regular radial solutions we
prove oscillatory behaviour around the explicitly known radial {\it singular}
solution, provided $p\in((n+4)/(n-4),p_c)$, where $p_c\in ((n+4)/(n-4),\infty]$
is a further critical exponent, which was introduced in a recent work by
Gazzola and the second author. The third author proved already that these
oscillations do not occur in the complementing case, where $p\ge p_c$.
  Concerning the Dirichlet problem we prove existence of at least one singular
solution with corresponding eigenvalue parameter. Moreover, for the extremal
solution in the bifurcation diagram for this nonlinear biharmonic eigenvalue
problem, we prove smoothness as long as $p\in((n+4)/(n-4),p_c)$.


title:
Switching effect upon the quantum Brownian motion near a reflecting
  boundary

abstract:
  The quantum Brownian motion of a charged particle in the electromagnetic
vacuum fluctuations is investigated near a perfectly reflecting flat boundary,
taking into account the smooth switching process in the measurement.
Constructing a smooth switching function by gluing together a plateau and the
Lorentzian switching tails, it is shown that the switching tails have a great
influence on the measurement of the Brownian motion in the quantum vacuum.
Indeed, it turns out that the result with a smooth switching function and the
one with a sudden switching function are qualitatively quite different. It is
also shown that anti-correlations between the switching tails and the main
measuring part plays an essential role in this switching effect. The switching
function can also be interpreted as a prototype of an non-equilibrium process
in a realistic measurement, so that the switching effect found here is expected
to be significant in actual applications in vacuum physics.


title: RS model with the small curvature and Bhabha scattering at the ILC

abstract:
  The Randall-Sundrum (RS) model with the small curvature is studied. In such a
scheme the mass spectrum of Kaluza-Klein (KK) gravitons is similar to that in a
model with one extra flat dimension. The gravity effects in the Bhabha
scattering at the energy 1 TeV are estimated. The calculations are based on the
analytical formula which describes virtual graviton contributions. It takes
into account both a discrete character of the mass spectrum and nonzero widths
of the KK gravitons.


title: Enhancement of Persistent Current in Metal Rings by Correlated Disorder

abstract:
  We study analytically the effect of a correlated random potential on the
persistent current in a one-dimensional ring threaded by a magnetic flux
$\phi$, using an Anderson tight-binding model. In our model, the system of
$N=2M$ atomic sites of the ring is assumed to be partitioned into $M$ pairs of
identical nearest-neighbour sites (dimers). The site energies for different
dimers are taken to be uncorrelated gaussian variables. For this system we
obtain the exact flux-dependent energy levels to second order in the random
site energies, using an earlier exact transfer matrix perturbation theory.
These results are used to study the mean persistent current generated by
$N_e\leq N$ spinless electrons occupying the $N_e$ lowest levels of the
flux-dependent energy band at zero temperature. Detailed analyses are carried
out in the limit $1\ll N_e\ll N$ and for a half-filled band ($N_e=N/2$), for
magnetic fluxes $-1/2 <\phi/\phi_0<1/2$. While the uncorrelated disorder leads
to a reduction of the persistent current, the disorder correlation acts to
enhance it. In particular, in the half-filled band case the correlated disorder
leads to a global flux-dependent enhancement of persistent current which has
the same form for even and odd $N_e$. At low filling of the energy band the
effect of the disorder on the persistent current is found to depend on the
parity of $N_e$: the correlated disorder yields a reduction of the current for
odd $N_e$ and an enhancement of the current for even $N_e$.


title:
Covariant particle statistics and intertwiners of the kappa-deformed
  Poincare algebra

abstract:
  To speak about identical particles - bosons or fermions - in quantum field
theories with kappa-deformed Poincare symmetry, one must have a kappa-covariant
notion of particle exchange. This means constructing intertwiners of the
relevant representations of kappa-Poincare. We show, in the simple case of
spinless particles, that intertwiners exist, and, supported by a perturbative
calculation to third order in 1/kappa, make a conjecture about the existence
and uniqueness of a certain preferred intertwiner defining particle exchange in
kappa-deformed theories.


title: Nos\'e-Hoover Dynamics in Quantum Phase Space

abstract:
  Thermal fluctuations in time-dependent quantum processes are treated by a
constant-temperature generalization of Wigner's formulation of quantum
mechanics in phase space. To this end, quantum Nos\`e-Hoover dynamics is
defined by generalizing the Moyal bracket. Computational applications of the
formalism, together with further theoretical developments, are discussed.


title: One Hub-One Process: A Tool Based View on Regulatory Network Topology

abstract:
  The relationship between the regulatory design and the functionality of
molecular networks is a key issue in biology. Modules and motifs have been
associated to various cellular processes, thereby providing anecdotal evidence
for performance based localization on molecular networks. To quantify
structure-function relationship we investigate similarities of proteins which
are close in the regulatory network of the yeast Saccharomyces Cerevisiae. We
find that the topology of the regulatory network show weak remnants of its
history of network reorganizations, but strong features of co-regulated
proteins associated to similar tasks. This suggests that local topological
features of regulatory networks, including broad degree distributions, emerge
as an implicit result of matching a number of needed processes to a finite
toolbox of proteins.


title: Impact of Rotation on the Evolution of Low-Mass Stars

abstract:
  High precision photometry and spectroscopy of low-mass stars reveal a variety
of properties standard stellar evolution cannot predict. Rotation, an essential
ingredient of stellar evolution, is a step towards resolving the discrepancy
between model predictions and observations. The first rotating stellar model,
continuously tracing a low-mass star from the pre-main sequence onto the
horizontal branch, is presented. The predicted luminosity functions of stars of
globular clusters and surface rotation velocities on the horizontal branch are
discussed.


title:
Properties of high-degree oscillation modes of the Sun observed with
  Hinode/SOT

abstract:
  Aims. With the Solar Optical Telescope on Hinode, we investigate the basic
properties of high-degree solar oscillations observed at two levels in the
solar atmosphere, in the G-band (formed in the photosphere) and in the Ca II H
line (chromospheric emission).
  Methods. We analyzed the data by calculating the individual power spectra as
well as the cross-spectral properties, i.e., coherence and phase shift. The
observational properties are compared with a simple theoretical model, which
includes the effects of correlated noise.
  Results. The results reveal significant frequency shifts between the Ca II H
and G-band spectra, in particular above the acoustic cut-off frequency for
pseudo-modes. The cross-spectrum phase shows peaks associated with the acoustic
oscillation (p-mode) lines, and begins to increase with frequency around the
acoustic cut-off. However, we find no phase shift for the (surface gravity
wave) f-mode. The observed properties for the p-modes are qualitatively
reproduced in a simple model with a correlated background if the correlated
noise level in the Ca II H data is higher than in the G-band data. These
results suggest that multi-wavelength observations of solar oscillations, in
combination with the traditional intensity-velocity observations, may help to
determine the level of the correlated background noise and to determine the
type of wave excitation sources on the Sun.


title: Symplectic critical surfaces in K\"ahler surfaces

abstract:
  Let $M$ be a K\"ahler surface and $\Sigma$ be a closed symplectic surface
which is smoothly immersed in $M$. Let $\alpha$ be the K\"ahler angle of
$\Sigma$ in $M$. We first deduce the Euler-Lagrange equation of the functional
$L=\int_{\Sigma}\frac{1}{\cos\alpha}d\mu$ in the class of symplectic surfaces.
It is $\cos^3\alpha H=(J(J\nabla\cos\alpha)^\top)^\bot$, where $H$ is the mean
curvature vector of $\Sigma$ in $M$, $J$ is the complex structure compatible
with the K\"ahler form $\omega$ in $M$, which is an elliptic equation. We then
study the properties of the equation.


title: Schelling's Segregation Model: Parameters, Scaling, and Aggregation

abstract:
  Thomas Schelling proposed an influential simple spatial model to illustrate
how, even with relatively mild assumptions on each individual's nearest
neighbor preferences, an integrated city would likely unravel to a segregated
city, even if all individuals prefer integration. Aggregation relates to
individuals coming together to form groups and global aggregation corresponds
to segregation. Many authors assumed that the segregation which Schelling
observed in simulations on very small cities persists for larger, realistic
size cities. We devise new measures to quantify the segregation and unlock its
dependence on city size, disparate neighbor comfortability threshold, and
population density. We identify distinct scales of global aggregation, and show
that the striking global aggregation Schelling observed is strictly a small
city phenomenon. We also discover several scaling laws for the aggregation
measures.


title: Radiative Transfer in Special Relativity: Covariance

abstract:
  The purpose is to introduce in a clear and direct way the students of
undergraduate courses in physics and/or astronomy to the subject of radiative
transfer. A pedagogical revision is made in order to obtain the radiative
transfer equation, its restrictions and the different types of interactions
present between the radiation and the matter. Because in the classical
literature about radiative transfer the covariance is not fully developed, we
show in an explicit manner detail calculations and then we discuss the
relativistic effects.


title:
Thermodynamical description of the interaction between holographic dark
  energy and dark matter

abstract:
  We present a thermodynamical description of the interaction between
holographic dark energy and dark matter. If holographic dark energy and dark
matter evolve separately, each of them remains in thermodynamic equilibrium. A
small interaction between them may be viewed as a stable thermal fluctuation
that brings a logarithmic correction to the equilibrium entropy. From this
correction we obtain a physical expression for the interaction which is
consistent with phenomenological descriptions and passes reasonably well the
observational tests.


title:
Soft X-ray emissions of highly charged Si VII--Si XII in cool
  star--Procyon

abstract:
  Different observation data for cool star--Procyon (Obs\_IDs of 63, 1461 and
1224) available from {\it Chandra Data Public Archive} were co-added and
analyzed. Emissivities of emission lines of highly charged silicon ions (Si
VII--Si XII) were calculated over temperatures by adopting the published data
of Liang et al. (2007, {\it Atom. Data and Nucl. Data Tables}, {\bf 93}, 375).
Using the emission measure derived by Raassen et al. (2002, A&A, {\bf 389},
228), the theoretical line fluxes are predicted, and the theoretical spectra
are constructed by assuming the Gaussian profile with instrumental broadening
(0.06 \AA). By detailed comparison between observation and predictions, several
emissions lines are identified firstly such as emissions at 43.663 \AA (Si XI),
45.550 \AA (Si XII), 46.179 \AA (Si VIII), 50.874 \AA (Si X), 64.668 \AA (Si
IX), and 73.189 \AA (Si VII) etc. Several emission lines are re-assigned in
this work, such as the emission line at 52.594 \AA to Si X (52.612 \AA), at
69.641 \AA to the blending of Si VII (69.632 \AA) and Si VIII (69.664 \AA)
lines, as well as at 70.050 \AA to Si VII (70.027 \AA). The prediction reveals
the large discrepancies between the $3s$--$2p$ line (63.715 \AA) {\it versus}
3d--$2p$ line (61.012 \AA) again for lower charge stage Si VIII. Solar flare
observation is also added for the assessment of present calculation. Different
assignments for some lines between Procyon and solar flare, have been found to
be due to the hotter emitter in Sun than in Procyon coronae.


title: Comments on TPC and RPC calibrations reported by the HARP Collaboration

abstract:
  The HARP Collaboration recently published calibrations of their TPC and RPC
detectors, and differential cross-sections of large-angle pion production in
proton-nucleus collisions. We argue that these calibrations are biased and
cross-sections based on them should not be trusted.


title: Time propagation of constrained coupled Gaussian wave packets

abstract:
  The dynamics of quantum systems can be approximated by the time propagation
of Gaussian wave packets. Applying a time dependent variational principle, the
time evolution of the parameters of the coupled Gaussian wave packets can be
calculated from a set of ordinary differential equations. Unfortunately, the
set of equations is ill-behaved in most practical applications, depending on
the number of propagated Gaussian wave packets, and methods for regularization
are needed. We present a general method for regularization based on applying
adequate nonholonomic inequality constraints to the evolution of the
parameters, keeping the equations of motion well-behaved. The power of the
method is demonstrated for a non-integrable system with two degrees of freedom.


title: First order operators and boundary triples

abstract:
  The aim of the present paper is to introduce a first order approach to the
abstract concept of boundary triples for Laplace operators. Our main
application is the Laplace operator on a manifold with boundary; a case in
which the ordinary concept of boundary triples does not apply directly. In our
first order approach, we show that we can use the usual boundary operators also
in the abstract Green's formula. Another motivation for the first order
approach is to give an intrinsic definition of the Dirichlet-to-Neumann map and
intrinsic norms on the corresponding boundary spaces. We also show how the
first order boundary triples can be used to define a usual boundary triple
leading to a Dirac operator.


title:
Gravitational dynamics of an infinite shuffled lattice: early time
  evolution and universality of non-linear correlations

abstract:
  In two recent articles a detailed study has been presented of the out of
equilibrium dynamics of an infinite system of self-gravitating points initially
located on a randomly perturbed lattice. In this article we extend the
treatment of the early time phase during which strong non-linear correlations
first develop, prior to the onset of ``self-similar'' scaling in the two point
correlation function. We establish more directly, using appropriate
modifications of the numerical integration, that the development of these
correlations can be well described by an approximation of the evolution in two
phases: a first perturbative phase in which particles' displacements are small
compared to the lattice spacing, and a subsequent phase in which particles
interact only with their nearest neighbor. For the range of initial amplitudes
considered we show that the first phase can be well approximated as a
transformation of the perturbed lattice configuration into a Poisson
distribution at the relevant scales. This appears to explain the
``universality'' of the spatial dependence of the asymptotic non-linear
clustering observed from both shuffled lattice and Poisson initial conditions.


title:
Gel-forming patchy colloids and network glass formers: Thermodynamic and
  Dynamic analogies

abstract:
  This article discusses recent attempts to provide a deeper understanding of
the thermoreversible "gel" state of colloidal matter and to unravel the
analogies between gels at the colloidal level and gels at the molecular level,
commonly known as network-forming strong liquids. The connection between
gel-forming patchy colloids and strong liquids is provided by the limited
valence of the inter-particle interactions, i.e. by the presence of a limit in
the number of bonded nearest neighbors.


title:
Epitaxial aluminium-nitride tunnel barriers grown by nitridation with a
  plasma source

abstract:
  High critical current-density (10 to 420 kA/cm^2)
superconductor-insulator-superconductor tunnel junctions with aluminium nitride
barriers have been realized using a remote nitrogen plasma from an inductively
coupled plasma source operated in a pressure range of 10^{-3} to 10^{-1} mbar.
We find a much better reproducibility and control compared to previous work.
  From the current-voltage characteristics and cross-sectional TEM images it is
inferred that, compared to the commonly used AlO_x barriers, the
poly-crystalline AlN barriers are much more uniform in transmissivity, leading
to a better quality at high critical current-densities.


title: X-ray afterglow light curves : toward standard candle ?

abstract:
  We investigate the clustering of afterglow light curves observed at X-ray and
optical wavelengths. We have constructed a sample of 61 bursts with known dis
tance and X-ray afterglow. This sample includes bursts observed by BeppoSAX,
XMM-Newton, Chandra, and SWIFT. We correct the light curves for cosmological ef
fects and compare the observed X-ray fluxes one day after the burst. We check
for correlations between the observed flux and the burst spectral and temporal
properties. We confirm the previous result of Boer and Gendre (2000) that X-ray
afterglow light curves cluster in luminosity, even when we consider the l ast
SWIFT data. We observe this clustering only for the afterglow light curves; the
inclusion of prompt-related data broaden the distribution. A similar clu
stering is observed for the optical light curves; GRB sources can be divided in
three classes, namely optical and X-ray bright afterglows, optical and X-ray
dim ones, and optically bright -X-ray dim ones. We argue that this clustering
is related to the fireball total energy, the external medium density, the
fraction of fireball energy going in relativistic electrons and magnetic
fields. These parameters can be either fixed to a standard va lue, or
correlated. We finally propose a method for the estimation of the GRB source
redshift based on the observed X-ray flux one day after the burst and optical
properties. Using this method, we compute a redshift of 1.4 +/- 0.2 for GRB
980519 and of 1.9 \+/- 0.3 for GRB 040827. We tested this method on three
recently detected SWIFT GRBs with known redshift, and found it in good
agreement with the reported distance from optical spectroscopy .


title: Pattern avoidance and the Bruhat order on involutions

abstract:
  We show that the principal order ideal below an element w in the Bruhat order
on involutions in a symmetric group is a Boolean lattice if and only if w
avoids the patterns 4321, 45312 and 456123. Similar criteria for signed
permutations are also stated. Involutions with this property are enumerated
with respect to natural statistics. In this context, a bijective correspondence
with certain Motzkin paths is demonstrated.


title:
A smooth foliation of convex hypersurfaces for quasi-hyper-Fuchsian
  manifolds

abstract:
  This submission has been withdrawn by the author and superseded by
arXiv:0804.0744.


title: On maximally superintegrable systems

abstract:
  Locally any completely integrable system is maximally superintegrable system
such as we have the necessary number of the action-angle variables. The main
problem is the construction of the single-valued additional integrals of motion
on the whole phase space by using these multi-valued action-angle variables.
Some constructions of the additional integrals of motion for the St\"ackel
systems and for the integrable systems related with two different quadratic
$r$-matrix algebras are discussed. Among these system there are the open
Heisenberg magnet and the open Toda lattices associated with the different root
systems.


title: Neutrino Lumps in Quintessence Cosmology

abstract:
  Neutrinos interacting with the quintessence field can trigger the accelerated
expansion of the Universe. In such models with a growing neutrino mass the
homogeneous cosmological solution is often unstable to perturbations. We
present static, spherically symmetric solutions of the Einstein equations in
the same models. They describe astophysical objects composed of neutrinos, held
together by gravity and the attractive force mediated by the quintessence
field. We discuss their characteristics as a function of the present neutrino
mass. We suggest that these objects are the likely outcome of the growth of
cosmological perturbations.


title: Dynamic states of cells adhering in shear flow: from slipping to rolling

abstract:
  Motivated by rolling adhesion of white blood cells in the vasculature, we
study how cells move in linear shear flow above a wall to which they can adhere
via specific receptor-ligand bonds. Our computer simulations are based on a
Langevin equation accounting for hydrodynamic interactions, thermal
fluctuations and adhesive interactions. In contrast to earlier approaches, our
model not only includes stochastic rules for the formation and rupture of
bonds, but also fully resolves both receptor and ligand positions. We identify
five different dynamic states of motion in regard to the translational and
angular velocities of the cell. The transitions between the different states
are mapped out in a dynamic state diagram as a function of the rates for bond
formation and rupture. For example, as the cell starts to adhere under the
action of bonds, its translational and angular velocities become synchronized
and the dynamic state changes from slipping to rolling. We also investigate the
effect of non-molecular parameters. In particular, we find that an increase in
viscosity of the medium leads to a characteristic expansion of the region of
stable rolling to the expense of the region of firm adhesion, but not to the
expense of the regions of free or transient motion. Our results can be used in
an inverse approach to determine single bond parameters from flow chamber data
on rolling adhesion.


title: Isolated large amplitude periodic motions of towed rigid wheels

abstract:
  This study investigates a low degree-of-freedom (DoF) mechanical model of
shimmying wheels. The model is studied using bifurcation theory and numerical
continuation. Self-excited vibrations, that is, stable and unstable periodic
motions of the wheel, are detected with the help of Hopf bifurcation
calculations. These oscillations are then followed over a large parameter range
for different damping values by means of the software package AUTO97. For
certain parameter regions, the branches representing large amplitude stable and
unstable periodic motions become isolated following an isola birth. These
regions are extremely dangerous from an engineering view-point if they are not
identified and avoided at the design stage.


title: Properties of holons in the Quantum Dimer Model

abstract:
  I introduce a doped two-dimensional quantum dimer model describing a doped
Mott insulator and retaining the original Fermi statistics of the electrons.
This model shows a rich phase diagram including a d-wave hole-pair
unconventional superconductor at small enough doping and a bosonic superfluid
at large doping. The hole kinetic energy is shown to favor binding of
topological defects to the bare fermionic holons turning them into bosons, in
agreement with arguments based on RVB wave-functions. Results are discussed in
the context of cuprates superconductors.


title:
Joint excitation probability for two harmonic oscillators in dimension
  one and the Mott problem

abstract:
  We analyze a one dimensional quantum system consisting of a test particle
interacting with two harmonic oscillators placed at the positions $a_1$, $a_2$,
with $a_1 >0$, $|a_2|>a_1$, in the two possible situations: $a_2>0$ and $a_2
<0$. At time zero the harmonic oscillators are in their ground state and the
test particle is in a superposition state of two wave packets centered in the
origin with opposite mean momentum. %$\pm M v_0$. Under suitable assumptions on
the physical parameters of the model, we consider the time evolution of the
wave function and we compute the probability $\mathcal{P}^{-}_{n_1 n_2} (t)$
(resp. $\mathcal{P}^{+}_{n_1 n_2} (t)$) that both oscillators are in the
excited states labelled by $n_1$, $n_2 >0$ at time $t > |a_2| v_0^{-1}$ when
$a_2 <0$ (resp. $a_2 >0$). We prove that $\mathcal{P}_{n_1 n_2}^- (t)$ is
negligible with respect to $\mathcal{P}_{n_1 n_2}^+ (t)$, up to second order in
time dependent perturbation theory. The system we consider is a simplified, one
dimensional version of the original model of a cloud chamber introduced by Mott
in \cite{m}, where the result was argued using euristic arguments in the
framework of the time independent perturbation theory for the stationary
Schr\"{o}dinger equation. The method of the proof is entirely elementary and it
is essentially based on a stationary phase argument. We also remark that all
the computations refer to the Schr\"{o}dinger equation for the three-particle
system, with no reference to the wave packet collapse postulate.


title:
Elastic proton-proton and proton-antiproton scattering: analysis of
  complete set of helicity amplitudes

abstract:
  The differential cross-sections are calculated for proton-proton and
proton-antiproton elastic scattering using the phenomenological model based on
the analytic parameterizations for global scattering parameters (total
cross-section and $\rho$ - parameter), crossing symmetry and derivative
relations. We confront our model predictions with experimental data in wide
range of energy and momentum transfer. The suggested method may be useful for
PAX Program (GSI) as well as for high-energy experiments at RHIC and LHC.


title:
Electromagnetically induced transparency in two channels of a $\Lambda$
  system

abstract:
  We show two channel electromagnetically induced transparency (EIT) spectra at
various optical power. The two channels are coupling field and probe field
absorption. It is shown that EIT width and intensity increases linearly with
pump power. A density matrix calculation is used to determine nature of EIT
spectra induced by optical field. It has been observed that EIT occurs in cases
when coupling laser is at fixed frequency while probe laser frequency is
scanned, when coupling laser is frequency scanned and probe is at fixed
frequency.


title: Parity-violating two-pion exchange nucleon-nucleon interaction

abstract:
  We calculate in chiral perturbation theory the parity-violating two-pion
exchange nucleon-nucleon potentials at leading one-loop order. At a distance of
$r= m_\pi^{-1} \simeq 1.4 $fm they amount to about $\pm 16%$ of the
parity-violating $1\pi$-exchange potential. We evaluate also the
parity-violating effects arising from $2\pi$-exchange with excitation of
virtual $\Delta(1232)$-isobars. These come out to be relatively small in
comparison to those from diagrams with only nucleon intermediate states. The
reason for this opposite behavior to the parity-conserving case is the blocking
of the dominant isoscalar central channel by CP-invariance. Furthermore, we
calculate the T-matrix related to the iteration of the parity-violating
$1\pi$-exchange with the parity-conserving one. The analytical results
presented in this work can be easily implemented into calculations of
parity-violating nuclear observables.


title:
Consequences of statistical sense determination for WIMP directional
  detection

abstract:
  We study the consequences of limited recoil sense reconstruction on the
number of events required to reject isotropy and detect a WIMP signal using a
directional detector. For a constant probability of determining the sense
correctly, 3-d read-out and zero background, we find that as the probability is
decreased from 1.0 to 0.75 the number of events required to reject isotropy
using the mean angle statistic is increased by a factor of a few. As the
probability is decreased further the number of events required using this
statistic increases sharply, and in fact isotropy can be rejected more easily
by discarding the sense information and using axial statistics. This however
requires an order of magnitude more events than vectorial data with perfect
sense determination. We also consider energy dependent probabilities of
correctly measuring the sense, 2-d read-out and non-zero background. Our main
conclusion regarding the sense determination is that correctly determining the
sense of the abundant, but less anisotropic, low energy recoils is most
important for minimising the number of events required.


title:
Evolution of the Fermi Surface across a Magnetic Order-Disorder
  Transition in the Two-Dimensional Kondo Lattice Model: A Dynamical Cluster
  Approach

abstract:
  We use the dynamical cluster approximation, with a quantum Monte Carlo
cluster solver on clusters of up to 16 orbitals, to investigate the evolution
of the Fermi surface across the magnetic order-disorder transition in the
two-dimensional doped Kondo lattice model. In the paramagnetic phase we observe
the generic hybridized heavy fermion band structure with large Luttinger
volume. In the antiferromagnetic phase, the heavy fermion band drops below the
Fermi surface giving way to hole pockets centered around k=(pi/2,pi/2) and
equivalent points. In this phase Kondo screening does not break down but the
topology of the resulting Fermi surface is that of a spin-density wave
approximation in which the localized spins are frozen.


title: Manin matrices and Talalaev's formula

abstract:
  We study special class of matrices with noncommutative entries and
demonstrate their various applications in integrable systems theory. They
appeared in Yu. Manin's works in 87-92 as linear homomorphisms between
polynomial rings; more explicitly they read: 1) elements in the same column
commute; 2) commutators of the cross terms are equal: $[M_{ij},
M_{kl}]=[M_{kj}, M_{il}]$ (e.g. $[M_{11}, M_{22}]=[M_{21}, M_{12}]$). We claim
that such matrices behave almost as well as matrices with commutative elements.
Namely theorems of linear algebra (e.g., a natural definition of the
determinant, the Cayley-Hamilton theorem, the Newton identities and so on and
so forth) holds true for them.
  On the other hand, we remark that such matrices are somewhat ubiquitous in
the theory of quantum integrability. For instance, Manin matrices (and their
q-analogs) include matrices satisfying the Yang-Baxter relation "RTT=TTR" and
the so--called Cartier-Foata matrices. Also, they enter Talalaev's
hep-th/0404153 remarkable formulas: $det(\partial_z-L_{Gaudin}(z))$,
$det(1-e^{-\p}T_{Yangian}(z))$ for the "quantum spectral curve", etc. We show
that theorems of linear algebra, after being established for such matrices,
have various applications to quantum integrable systems and Lie algebras, e.g
in the construction of new generators in $Z(U(\hat{gl_n}))$ (and, in general,
in the construction of quantum conservation laws), in the
Knizhnik-Zamolodchikov equation, and in the problem of Wick ordering. We also
discuss applications to the separation of variables problem, new Capelli
identities and the Langlands correspondence.


title: $\Sigma$-nuclear spin-orbit coupling from two-pion exchange

abstract:
  Using SU(3) chiral perturbation theory we calculate the density-dependent
complex-valued spin-orbit coupling strength $U_{\Sigma ls}(k_f)+ i W_{\Sigma
ls}(k_f)$ of a $\Sigma$ hyperon in the nuclear medium. The leading long-range
$\Sigma N$ interaction arises from iterated one-pion exchange with a $\Lambda$
or a $\Sigma$ hyperon in the intermediate state. We find from this unique
long-range dynamics a sizeable ``wrong-sign'' spin-orbit coupling strength of
$U_{\Sigma ls}(k_{f0}) \simeq -20$ MeVfm$^2$ at normal nuclear matter density
$\rho_0 = 0.16 $fm$^{-3}$. The strong $\Sigma N\to \Lambda N$ conversion
process contributes at the same time an imaginary part of $W_{\Sigma
ls}(k_{f0}) \simeq -12$ MeVfm$^2$. When combined with estimates of the
short-range contribution the total $\Sigma$-nuclear spin-orbit coupling becomes
rather weak.


title:
Fourier-Mukai transforms of line bundles on derived equivalent abelian
  varieties

abstract:
  We study the Fourier-Mukai functor D(Y) -> D(X) induced by the universal
family on a fine moduli space Y for simple semihomogeneous vector bundles on an
abelian variety X. The main result is that the Fourier-Mukai transform of a
very negative line bundle on Y is ample if and only if the bundles parametrized
by Y are nef.


title:
Mise en place de sc\'enarios pour la conception d'outils en Chirurgie
  Minimalement Invasive

abstract:
  Nowadays, more and more surgical interventions are carried out in Minimally
Invasive Surgery, to make the post-operative constraints less painful for the
patient. Actually, new surgical tools or medical products are designed after
informal discussions between surgeons and designers. The user requirements
documents are the main document used by the mechanical designers to design and
improve the product. Medical terms, often used by surgeons and employed to
explain their needs, don't allow for an instantaneous understanding by
designers. Unfortunately, this relation causes a dysfunction in the definition
cycle of the product. Our aim is to work on the design process, its assistance
thanks to methods and tools and on its organisation for better understandings
and more complementarities between surgeons and designers. We propose on this
article a design method already tested in the informatics domain: User Centred
Design which takes the user into account more effectively in the process
design. We already propose a scenario oriented design method centred on the
user and represented as a scenario (Scenario-Based Design). We start in this
article by clarifying these concepts before detailing their implementation for
the design of a new surgical tool.


title: A note on the least totient of a residue class

abstract:
  Let $q$ be a large prime number, $a$ be any integer, $\epsilon$ be a fixed
small positive quantity. Friedlander and Shparlinksi \cite{FSh} have shown that
there exists a positive integer $n\ll q^{5/2+\epsilon}$ such that $\phi(n)$
falls into the residue class $a \pmod q.$ Here, $\phi(n)$ denotes Euler's
function. In the present paper we improve this bound to $n\ll q^{2+\epsilon}.$


title: Bounds on the cardinality of partition

abstract: If A is infinite and well-ordered, then |2^A|<=|Part(A)|<=|A^A|.


title: Group testing with Random Pools: Phase Transitions and Optimal Strategy

abstract:
  The problem of Group Testing is to identify defective items out of a set of
objects by means of pool queries of the form "Does the pool contain at least a
defective?". The aim is of course to perform detection with the fewest possible
queries, a problem which has relevant practical applications in different
fields including molecular biology and computer science. Here we study GT in
the probabilistic setting focusing on the regime of small defective probability
and large number of objects, $p \to 0$ and $N \to \infty$. We construct and
analyze one-stage algorithms for which we establish the occurrence of a
non-detection/detection phase transition resulting in a sharp threshold, $\bar
M$, for the number of tests. By optimizing the pool design we construct
algorithms whose detection threshold follows the optimal scaling $\bar M\propto
Np|\log p|$. Then we consider two-stages algorithms and analyze their
performance for different choices of the first stage pools. In particular, via
a proper random choice of the pools, we construct algorithms which attain the
optimal value (previously determined in Ref. [16]) for the mean number of tests
required for complete detection. We finally discuss the optimal pool design in
the case of finite $p$.


title:
Guest Charge and Potential Fluctuations in Two-Dimensional Classical
  Coulomb Systems

abstract:
  A known generalization of the Stillinger-Lovett sum rule for a guest charge
immersed in a two-dimensional one-component plasma (the second moment of the
screening cloud around this guest charge) is more simply retrieved, just by
using the BGY hierarchy for a mixture of several species; the zeroth moment of
the excess density around a guest charge immersed in a two-component plasma is
also obtained. The moments of the electric potential are related to the excess
chemical potential of a guest charge; explicit results are obtained in several
special cases.


title: The pulsation modes of the pre-white dwarf PG 1159-035

abstract:
  PG 1159-035, a pre-white dwarf with T_eff=140,000 K, is the prototype of both
two classes: the PG1159 spectroscopic class and the DOV pulsating class.
Previous studies of PG 1159-035 photometric data obtained with the Whole Earth
Telescope (WET) showed a rich frequency spectrum allowing the identification of
122 pulsation modes. In this work, we used all available WET photometric data
from 1983, 1985, 1989, 1993 and 2002 to identify the pulsation periods and
identified 76 additional pulsation modes, increasing to 198 the number of known
pulsation modes in PG 1159-035, the largest number of modes detected in any
star besides the Sun. From the period spacing we estimated a mass M = 0.59 +/-
0.02 solar masses for PG 1159-035, with the uncertainty dominated by the
models, not the observation. Deviations in the regular period spacing suggest
that some of the pulsation modes are trapped, even though the star is a
pre-white dwarf and the gravitational settling is ongoing. The position of the
transition zone that causes the mode trapping was calculated at r_c = 0.83 +/-
0.05 stellar radius. From the multiplet splitting, we calculated the rotational
period P_rot = 1.3920 +/- 0.0008 days and an upper limit for the magnetic
field, B < 2000 G. The total power of the pulsation modes at the stellar
surface changed less than 30% for l=1 modes and less than 50% for l=2 modes. We
find no evidence of linear combinations between the 198 pulsation mode
frequencies. PG 1159-035 models have not significative convection zones,
supporting the hypothesis that nonlinearity arises in the convection zones in
cooler pulsating white dwarf stars.


title: On approximation of quantum channels

abstract:
  We develop an approximation approach to infinite dimensional quantum channels
based on detailed investigation of the continuity properties of entropic
characteristics of quantum channels and operations (trace-nonincreasing
completely positive maps) as functions of a pair ``channel, input state''. The
obtained results are then applied to the following problems: continuity of the
$\chi$-capacity as function of a channel; strong additivity of the
$\chi$-capacity for infinite dimensional channels; the analytical expression
for the convex closure of the output entropy of arbitrary quantum channel.


title: Simulation of highly idealized, atomic scale MQCA logic circuits

abstract:
  Spintronics logic devices based on majority gates formed by atomic-level
arrangements of spins in the crystal lattice is considered. The dynamics of
switching is modeled by time-dependent solution of the density-matrix equation
with relaxation. The devices are shown to satisfy requirements for logic.
Switching speed and dissipated energy are calculated and compared with
electronic transistors. The simulations show that for the highly idealized case
assumed here, it is possible to trade off size for speed and achieve lower
power operation than ultimately scaled CMOS devices.


title:
Power thresholds of morphology dependent induced thermal scattering in
  silica microresonators

abstract:
  Induced thermal scattering power thresholds have been calculated as a
function of size and laser pump frequency. The thermal coupling coefficients of
morphology dependent resonances were estimated by asymptotic methods. The
resulting power threshold is comparable with experimental observations of
thresholds of Raman lasing and thermal instability in spherical silica
resonators. Applications may include the remote measurement of the temperature
of aerosol droplets and the stabilization of microcavity lasers against thermal
oscillations and temperature deviations on microcavity. A silica resonator can
be used as an IR sensor, as well as an additional tool for precisely measuring
the thermal conductivity and heat capacity of a target in a microsphere by
calculating of the thermal shifts of eigenfrequencies in spectra of nonlinear
scattering.


title:
Block Toeplitz determinants, constrained KP and Gelfand-Dickey
  hierarchies

abstract:
  We propose a method for computing any Gelfand-Dickey tau function living in
Segal-Wilson Grassmannian as the asymptotics of block Toeplitz determinant
associated to a certain class of symbols. Also truncated block Toeplitz
determinants associated to the same symbols are shown to be tau function for
rational reductions of KP. Connection with Riemann-Hilbert problems is
investigated both from the point of view of integrable systems and block
Toeplitz operator theory. Examples of applications to algebro-geometric
solutions are given.


title:
A peculiar planetary nebula candidate in a globular cluster in the
  Fornax dwarf spheroidal galaxy

abstract:
  CONTEXT: Until now, only one planetary nebula (PN) has been known in the
Fornax dwarf spheroidal galaxy. AIMS: The discovery of a second PN candidate,
associated with one of the 5 globular clusters in the Fornax dwarf, is
reported. METHODS: Spectra of the globular cluster H5, obtained with the UVES
echelle spectrograph on the ESO Very Large Telescope, show [O III] line
emission at a radial velocity consistent with membership of the Fornax dwarf. A
possible counterpart of the [O III] emission is identified in archival images
from the Wide Field Planetary Camera 2 on board the Hubble Space Telescope. The
source of the emission is located about 1.5" (less than one core radius)
southwest of the centre of the cluster. RESULTS: The emission line source is
identified as a likely PN, albeit with several peculiar properties. No Hbeta,
He I, or He II line emission is detected and the [O III]/Hbeta ratio is >25 (2
sigma). The expansion velocity inferred from the [O III] 5007 AA line is about
55 km/s, which is large for a PN. The diameter measured on the HST images is
about 0.23" or 0.15 pc at the distance of the Fornax dSph. CONCLUSIONS: This
object doubles the number of known PNe in Fornax, and is only the 5th PN
associated with an old GC for which direct imaging is available. It may be a
member of the rare class of extremely H-deficient PNe, the second such case
found in a GC.


title: Fluctuation Properties of Steady-State Langevin Systems

abstract:
  Motivated by stochastic models of climate phenomena, the steady-state of a
linear stochastic model with additive Gaussian white noise is studied.
Fluctuation theorems for nonequilibrium steady-states provide a constraint on
the character of these fluctuations. The properties of the fluctuations which
are unconstrained by the fluctuation theorem are investigated and related to
the model parameters. The irreversibility of trajectory segments, which
satisfies a fluctuation theorem, is used as a measure of nonequilibrium
fluctuations. The moments of the irreversibility probability density function
(pdf) are found and the pdf is seen to be non-Gaussian. The average
irreversibility goes to zero for short and long trajectory segments and has a
maximum for some finite segment length, which defines a characteristic
timescale of the fluctuations. The initial average irreversibility growth rate
is equal to the average entropy production and is related to
noise-amplification. For systems with a separation of deterministic timescales,
modes with timescales much shorter than the trajectory timespan and whose noise
amplitudes are not asymptotically large, do not, to first order, contribute to
the irreversibility statistics, providing a potential basis for dimensional
reduction.


title: Renormalized Polyakov loops in many representations

abstract:
  We present a renormalization procedure for Polyakov loops which explicitly
implements the fact that the renormalization constant depends only on the
ultraviolet cutoff. Using this we study the renormalized Polyakov loops in all
representations upto the {\bf 27} of the gauge group SU(3). We find good
evidence for Casimir scaling of the Polyakov loops and for approximate large-N
factorization. By studying many loops together, we are able to show that there
is a matrix model with a single coupling which can describe the high
temperature phase of QCD, although it is hard to construct explicitly. We
present the first results for the non-vanishing renormalized octet loop in the
thermodynamic limit below the SU(3) phase transition, and estimate the
associated string breaking distance and the gluelump binding energy. By
studying the connection of the direct renormalization procedure with a
generalization of an earlier suggestion which goes by the name of the $Q\bar Q$
renormalization procedure, we find that they are functionally equivalent.


title:
Asymptotic estimations of power thresholds and anti-Stokes frequency of
  laser induced thermal scattering in microresonators

abstract:
  A derivation of the asymptotic expressions for the threshold intensity of
laser induced thermal scattering in silica microresonator when illuminated with
a plane wave is present. The calculation of anti-Stokes thermal combination
frequencies are made for the spherical high Q-factor microresonators. The three
modes regime of nonlinear interaction is considered. One pump-driven, two
signal modes, and one mode of temperature relaxation are taken into account,
satisfying morphology-dependent input and output resonances. There are low
power thresholds for laser induced thermal scattering at morphology dependent
resonances.


title:
Disentangling CP phases in nearly degenerate resonances: neutralino
  production via Higgs at a muon collider

abstract:
  In the CP-violating Minimal Supersymmetric Standard Model, we study the pair
production of neutralinos at center-of-mass energies around the heavy neutral
Higgs boson resonances. For longitudinally polarized muon beams, we analyze CP
asymmetries which are sensitive to the interference of the two heavy neutral
Higgs bosons. Due to radiatively induced scalar-pseudoscalar transitions, the
CP asymmetries can be strongly enhanced when the resonances are nearly
degenerate, as in the Higgs decoupling limit. The Higgs couplings to the
neutralino sector can then be analyzed in the presence of CP violating phases.
We present a detailed numerical analysis of the cross sections, neutralino
branching ratios, and the CP observables. We find that radiatively induced CP
violation in the Higgs sector leads to sizable CP-asymmetries, which are
accessible in future measurements at a muon collider. However, we expect that
our proposed method should be applicable to other processes with nearly
degenerate scalar resonances, even at hadron colliders.


title: Calibration systems and methods for the ANTARES neutrino telescope

abstract:
  The ANTARES neutrino telescope is currently being constructed in the
Mediterranean Sea. The complete detector will consist of 12 strings,
supplemented by an additional instrumentation line. Nine strings are at present
deployed of which five are already connected to the shore and operating. Each
string is equipped with 75 Optical Modules (OMs) housing the photomultipliers
to detect the Cherenkov light induced by the charged particles produced in
neutrino reactions. An accurate measurement of the Cherenkov photon arrival
times as well as the positions and orientations of the OMs is required for a
precise reconstruction of the direction of the detected neutrinos. For this
purpose the ANTARES detector is provided with several system s to facilitate
the calibration of the detector. The time calibration is performed using light
pulses emitted from LED and laser devices. The positioning is done via acoustic
triangulation using hydrophones. Additionally, local tilt angles and the
orientations of the modules are measured with a set of tiltmeters and
compasses. In this paper, it is demonstrated that the ANTARES time and
alignment calibration systems operate successfully in situ. In particular, it
is shown that the ANTARES read-out electronics is capable of reaching a
sub-nanosecond time resolution.


title: Neutron Interactions as Seen by A Segmented Germanium Detector

abstract:
  The GERmanium Detector Array, GERDA, is designed for the search for
``neutrinoless double beta decay'' (0-nu-2-beta) with germanium detectors
enriched in Ge76. An 18-fold segmented prototype detector for GERDA Phase II
was exposed to an AmBe neutron source to improve the understanding of neutron
induced backgrounds. Neutron interactions with the germanium isotopes
themselves and in the surrounding materials were studied. Segment information
is used to identify neutron induced peaks in the recorded energy spectra. The
Geant4 based simulation package MaGe is used to simulate the experiment. Though
many photon peaks from germanium isotopes excited by neutrons are correctly
described by Geant4, some physics processes were identified as being
incorrectly treated or even missing.


title:
Correlation of the highest energy cosmic rays with nearby extragalactic
  objects

abstract:
  Using data collected at the Pierre Auger Observatory during the past 3.7
years, we demonstrated a correlation between the arrival directions of cosmic
rays with energy above ~ 6x10^{19} electron volts and the positions of active
galactic nuclei (AGN) lying within ~ 75 megaparsecs. We rejected the hypothesis
of an isotropic distribution of these cosmic rays with at least a 99%
confidence level from a prescribed a priori test. The correlation we observed
is compatible with the hypothesis that the highest energy particles originate
from nearby extragalactic sources whose flux has not been substantially reduced
by interaction with the cosmic background radiation. AGN or objects having a
similar spatial distribution are possible sources.


title:
Oxygen isotope effect on superconductivity and magnetism in
  Y_1-xPr_xBa_2Cu_3O_7-\delta

abstract:
  Oxygen isotope (^{16}O/^{18}O) effects (OIE's) on the superconducting
transition (T_c), the spin-glass ordering (T_g), and the antiferromagnetic
ordering (T_N) temperatures were studied for Y_1-xPr_xBa_2Cu_3O_7-\delta as a
function of Pr content (0.0\leq x \leq 1.0). The OIE on T_c increases with
increasing x up to x\approx0.55, where superconductivity disappears. For
decreasing x the OIE's on T_N and T_g increase down to x\approx 0.7 where
antiferromagnetic order and down to x\approx0.3 where spin-glass behavior
vanish, respectively. The OIE's on T_g and T_N are found to have {\it opposite
signs} as compared to the OIE on T_c. All OIE's are suggested to arise from the
isotope dependent mobility (kinetic energy) of the charge carriers.


title: Density operators and selective measurements

abstract:
  It is widely believed that statistical interpretation of quantum mechanics
requires that density operators representing quantum states be normalized. We
present a description of selective measurements in terms of density operators.
The description is inspired by Schwinger's Algebra of Microscopic Measurements.
Density operators used are not normalized. We do not know applications of
density operators requiring normalization.


title: The Pion Cloud: Insights into Hadron Structure

abstract:
  Modern nuclear theory presents a fascinating study in contrasting approaches
to the structure of hadrons and nuclei. Nowhere is this more apparent than in
the treatment of the pion cloud. As this discussion really begins with Yukawa,
it is entirely appropriate that this invited lecture at the Yukawa Institute in
Kyoto should deal with the issue.


title:
A Quantum Like Interpretation and Solution of Einstein, Podolsky, and
  Rosen Paradox in Quantum Mechanics

abstract:
  We discuss the Einstein, Podolsky, and Rosen paradox as it was formulated by
Asher Peres in 1992 [4]. On this basis we realize an algebraic quantum like
elaboration showing that in this formulation the paradox may be still
interpreted and solved.


title:
Spectral Energy Distributions of High Mass Proto Stellar Objects -
  Evidence for High Accretion Rates

abstract:
  The spectral energy distributions (SEDs), spanning the mid-infrared to
millimeter wavelengths, of a sample of 13 high-mass protostellar objects
(HMPOs) were studied using a large archive of 2-D axisymmetric radiative
transfer models. Measurements from the Spitzer GLIMPSE and MIPSGAL surveys and
the MSX survey were used in addition to our own surveys at millimeter and
submillimeter wavelengths to construct the SEDs, which were then fit to the
archive of models. These models assumed that stars of all masses form via
accretion and allowed us to make estimates for the masses, luminosities and
envelope accretion rates for the HMPOs. The models fit the observed SEDs well.
The implied envelope accretion rates are high, $\approx 10^{-2.5} \msun/yr$,
consistent with the accretion-based scenario of massive star formation. With
the fitted accretion rates and with mass estimates of up to $\sim 20 \msun$ for
these objects, it appears plausible that stars with stellar masses $M_{\ast} >
20 \msun$ can form via accretion.


title:
Weak-Pseudo-Hermiticity of Non-Hermitian Hamiltonians with
  Position-Dependent Mass

abstract:
  We extend the definition of eta-weak-pseudo-Hermiticity to the class of
potentials endowed with position-dependent mass. The construction of
non-Hermitian Hamiltonians through some generating function are obtained.
Special cases of potentials are thus deduced.


title:
High quality mechanical and optical properties of commercial silicon
  nitride membranes

abstract:
  We have measured the optical and mechanical loss of commercial silicon
nitride membranes. We find that 50 nm-thick, 1 mm^2 membranes have mechanical Q
> 10^6 at 293 K, and Q > 10^7 at 300 mK, well above what has been observed in
devices with comparable dimensions. The near-IR optical loss at 293 K is less
than 2E-4. This combination of properties make these membranes attractive
candidates for studying quantum effects in optomechanical systems.


title:
The VLT-FLAMES survey of massive stars: atmospheric parameters and
  rotational velocity distributions for B-type stars in the Magellanic Clouds

abstract:
  We provide atmospheric parameters and rotational velocities of a large sample
(~400) of O- and early B-type stars, analysed in a homogeneous and consistent
manner, for use in constraining theoretical models. Comparison of the
rotational velocities with evolutionary tracks suggest that the end of core
hydrogen burning occurs later than currently predicted. We also show that the
large number of the luminous blue supergiants observed in the fields are
unlikely to have directly evolved from main-sequence massive O-type stars as
neither their low rotational velocities or position on the H-R diagram are
predicted. We suggest that blue-loops or mass-transfer binary systems may
populate the blue supergiant regime. By comparing the rotational velocity
distributions of the Magellanic Cloud stars to a similar Galactic sample we
find that (at 3sigma confidence level) massive stars (above 8Msun) in the SMC
rotate faster than those in the solar neighbourhood. However there appears to
be no significant difference between the rotational velocity distributions in
the Galaxy and the LMC. We find that the vsini distributions in the SMC and LMC
can modelled with an intrinsic rotational velocity distribution which is a
Gaussian peaking at 175km/s (SMC) and 100km/s (LMC). We find that in NGC346 in
the SMC, the 10-25Msun main-sequence stars appear to rotate faster than their
higher mass counterparts. Recently Yoon et al. (2006) have determined rates of
GRBs by modelling rapidly rotating massive star progenitors. Our measured
rotational velocity distribution for the 10-25Msun stars is peaked at slightly
higher velocities than they assume, supporting the idea that GRBs could come
from rapid rotators with initial masses as low as 14Msun at low metallicities.
(abridged).


title: Exactly Solvable Potentials by SO(2,2) Dynamical Algebra

abstract:
  The differential realization of the potential group SO(2,2) is used. The
spectrum-generating algebra for a kind of exactly solvable potentials endowed
with position-dependent mass is constructed.


title: Random Homogenization of Fractional Obstacle Problems

abstract:
  We use a characterization of the fractional Laplacian as a Dirichlet to
Neumann operator for an appropriate differential equation to study its obstacle
problem in perforated domains.