title:
Broadband dielectric spectroscopy on benzophenone: alpha relaxation,
  beta relaxation, and mode coupling theory

abstract:
  We have performed a detailed dielectric investigation of the relaxational
dynamics of glass-forming benzophenone. Our measurements cover a broad
frequency range of 0.1 Hz to 120 GHz and temperatures from far below the glass
temperature well up into the region of the small-viscosity liquid. With respect
to the alpha relaxation this material can be characterized as a typical
molecular glass former with rather high fragility. A good agreement of the
alpha relaxation behavior with the predictions of the mode coupling theory of
the glass transition is stated. In addition, at temperatures below and in the
vicinity of Tg we detect a well-pronounced beta relaxation of Johari-Goldstein
type, which with increasing temperature develops into an excess wing. We
compare our results to literature data from optical Kerr effect and depolarized
light scattering experiments, where an excess-wing like feature was observed in
the 1 - 100 GHz region. We address the question if the Cole-Cole peak, which
was invoked to describe the optical Kerr effect data within the framework of
the mode coupling theory, has any relation to the canonical beta relaxation
detected by dielectric spectroscopy.


title:
A limiting velocity for quarkonium propagation in a strongly coupled
  plasma via AdS/CFT

abstract:
  We study the dispersion relations of mesons in a particular hot strongly
coupled supersymmetric gauge theory plasma. We find that at large momentum k
the dispersion relations become omega = v_0 k + a + b/k + ..., where the
limiting velocity v_0 is the same for mesons with any quantum numbers and
depends only on the ratio of the temperature to the quark mass T/m_q. We
compute a and b in terms of the meson quantum numbers and T/m_q. The limiting
meson velocity v_0 becomes much smaller than the speed of light at temperatures
below but close to T_diss, the temperature above which no meson bound states at
rest in the plasma are found. From our result for v_0, we find that the
temperature above which no meson bound states with velocity v exist is
T_diss(v) \simeq (1-v^2)^(1/4) T_diss, up to few percent corrections.We thus
confirm by direct calculation of meson dispersion relations a result inferred
indirectly in previous work via analysis of the screening length between a
static quark and antiquark in a moving plasma. Although we do not do our
calculations in QCD, we argue that the qualitative features of the dispersion
relation we compute, including in particular the relation between dissociation
temperature and meson velocity, may apply to bottomonium and charmonium mesons
propagating in the strongly coupled plasma of QCD. We discuss how our results
can contribute to understanding quarkonium physics in heavy ion collisions.


title: Maximal small extensions of o-minimal structures

abstract:
  A proper elementary extension of a model is called small if it realizes no
new types over any finite set in the base model. We answer a question of
Marker, and show that it is possible to have an o-minimal structure with a
maximal small extension. Our construction yields such a structure for any
cardinality. We show that in some cases, notably when the base structure is
countable, the maximal small extension has maximal possible cardinality.


title: The causal boundary of wave-type spacetimes

abstract:
  A complete and systematic approach to compute the causal boundary of
wave-type spacetimes is carried out. The case of a 1-dimensional boundary is
specially analyzed and its critical appearance in pp-wave type spacetimes is
emphasized. In particular, the corresponding results obtained in the framework
of the AdS/CFT correspondence for holography on the boundary, are reinterpreted
and very widely generalized. Technically, a recent new definition of causal
boundary is used and stressed. Moreover, a set of mathematical tools is
introduced (analytical functional approach, Sturm-Liouville theory, Fermat-type
arrival time, Busemann-type functions).


title: Some families of increasing planar maps

abstract:
  Stack-triangulations appear as natural objects when one wants to define some
increasing families of triangulations by successive additions of faces. We
investigate the asymptotic behavior of rooted stack-triangulations with $2n$
faces under two different distributions. We show that the uniform distribution
on this set of maps converges, for a topology of local convergence, to a
distribution on the set of infinite maps. In the other hand, we show that
rescaled by $n^{1/2}$, they converge for the Gromov-Hausdorff topology on
metric spaces to the continuum random tree introduced by Aldous. Under a
distribution induced by a natural random construction, the distance between
random points rescaled by $(6/11)\log n$ converge to 1 in probability.
  We obtain similar asymptotic results for a family of increasing
quadrangulations.


title:
Real-time digital signal processor implementation of self-calibrating
  pulse-shape discriminator for high purity germanium

abstract:
  Pulse-shape analysis of the ionization signals from germanium gamma-ray
spectrometers is a method for obtaining information that can characterize an
event beyond just the total energy deposited in the crystal. However, as
typically employed, this method is data-intensive requiring the digitization,
transfer, and recording of electronic signals from the spectrometer. A hardware
realization of a real-time digital signal processor for implementing a
parametric pulse shape is presented. Specifically, a previously developed
method for distinguishing between single-site and multi-site gamma-ray
interactions is demonstrated in an on-line digital signal processor, compared
with the original off-line pulse-shape analysis routine, and shown to have no
significant difference. Reduction of the amount of the recorded information per
event is shown to translate into higher duty-cycle data acquisition rates while
retaining the benefits of additional event characterization from pulse-shape
analysis.


title:
HST NIR Snapshot Survey of 3CR Radio Source Counterparts II: An Atlas
  and Inventory of the Host Galaxies, Mergers and Companions

abstract:
  We present the second part of an H-band (1.6 microns) atlas of z<0.3 3CR
radio galaxies, using the Hubble Space Telescope Near Infrared Camera and
Multi-Object Spectrometer (HST NICMOS2). We present new imaging for 21 recently
acquired sources, and host galaxy modeling for the full sample of 101
(including 11 archival) -- an 87% completion rate. Two different modeling
techniques are applied, following those adopted by the galaxy morphology and
the quasar host galaxy communities. Results are compared, and found to be in
excellent agreement, although the former breaks down in the case of strongly
nucleated sources. Companion sources are tabulated, and the presence of
mergers, tidal features, dust disks and jets are catalogued. The tables form a
catalogue for those interested in the structural and morphological dust-free
host galaxy properties of the 3CR sample, and for comparison with morphological
studies of quiescent galaxies and quasar host galaxies. Host galaxy masses are
estimated, and found to typically lie at around 2*10^11 solar masses. In
general, the population is found to be consistent with the local population of
quiescent elliptical galaxies, but with a longer tail to low Sersic index,
mainly consisting of low-redshift (z<0.1) and low-radio-power (FR I) sources. A
few unusually disky FR II host galaxies are picked out for further discussion.
Nearby external sources are identified in the majority of our images, many of
which we argue are likely to be companion galaxies or merger remnants. The
reduced NICMOS data are now publicly available from our website
(http://archive.stsci.edu/prepds/3cr/)


title: Irreducible Representations of Groupoid $C^*$-algebras

abstract:
  If $G$ is a second countable locally compact Hausdorff groupoid with Haar
system, we show that every representation induced from an irreducible
representation of a stability group is irreducible.


title: Theory of Anomalous Quantum Hall Effects in Graphene

abstract:
  Recent successes in manufacturing of atomically thin graphite samples
(graphene) have stimulated intense experimental and theoretical activity. The
key feature of graphene is the massless Dirac type of low-energy electron
excitations. This gives rise to a number of unusual physical properties of this
system distinguishing it from conventional two-dimensional metals. One of the
most remarkable properties of graphene is the anomalous quantum Hall effect. It
is extremely sensitive to the structure of the system; in particular, it
clearly distinguishes single- and double-layer samples. In spite of the
impressive experimental progress, the theory of quantum Hall effect in graphene
has not been established. This theory is a subject of the present paper. We
demonstrate that the Landau level structure by itself is not sufficient to
determine the form of the quantum Hall effect. The Hall quantization is due to
Anderson localization which, in graphene, is very peculiar and depends strongly
on the character of disorder. It is only a special symmetry of disorder that
may give rise to anomalous quantum Hall effects in graphene. We analyze the
symmetries of disordered single- and double-layer graphene in magnetic field
and identify the conditions for anomalous Hall quantization.


title: A combined search for the standard model Higgs boson at sqrt{s}=1.96 TeV

abstract:
  We present new results of the search for WH to lepton neutrino b b production
in ppbar collisions at a center of mass energy of sqrt{s}=1.96 TeV, based on a
dataset with integrated luminosity of 0.44 fb-1. We combine these new results
with previously published searches by the D0 collaboration, for WH and ZH
production analyzed in the MET b b final state, for ZH (to l+l- b b)
production, for WH (to WWW) production, and for H (to WW) direct production. No
signal-like excess is observed either in the WH analysis or in the combination
of all D0 Higgs boson analyses. We set 95% C.L. (expected) upper limits on to
1.9 (3.3) pb for Higgs boson masses between 105 and 145 GeV, to be compared to
the theoretical prediction of 0.13 pb for a standard model (SM) Higgs boson
with mass m_H=115 GeV. After combination with the other D0 Higgs boson
searches, we obtain for m_H=115 GeV an observed (expected) limit 8.5 (12.1)
times higher than the SM predicted Higgs boson production cross section. For
m_H=160 GeV, the corresponding observed (expected) ratio is 10.2 (9.0).


title:
Search for ZZ and Z\gamma^* production in p-barp collisions at sqrt(s) =
  1.96 TeV and limits on anomalous ZZZ and ZZ\gamma^* couplings

abstract:
  We present a study of four muon, four electron, and two muon two electron
events using 1 fb^(-1) of data collected with the D0 detector at the Fermilab
Tevatron p-barp Collider at sqrt(s) = 1.96 TeV. Requiring the lepton pair
masses to be greater than 30 GeV, we observe one event, consistent with the
expected background of 0.13 +- 0.03 events and with the predicted standard
model ZZ and Z\gamma^* production of 1.71 +-0.15 events. We set an upper limit
on the ZZ and Z\gamma^* cross section of 4.4 pb at the 95% C.L. We also derive
limits on anomalous neutral trilinear ZZZ and ZZ\gamma^* gauge couplings. The
one-parameter 95%$ C.L. coupling limits with a form factor scale Lambda = 1.2
TeV are -0.28 < f_(40)^Z < 0.28, -0.31 < f_(50)^Z < 0.29, -0.26 < f_(40)^\gamma
< 0.26, and -0.30 < f_(5 0)^\gamma < 0.28.


title:
Some remarks on Causality Theory and Variational Methods in Lorentzian
  manifolds

abstract:
  In this conference published in 1997 some problems on the geodesics of a
Lorentzian manifold concerning causality and infinite-dimensional variational
methods, are pointed out. Even though a big progress on many of these questions
have been carried out since then, some computations in this paper may be useful
and have not been published elsewhere. Among them, for example, the following
one (Section 3). Consider a spacetime which can be written globally as a
product $R x M$, such that the natural vector field associated to the
coordinate $t$ in $R$ is timelike. When is this spacetime globally hyperbolic
with Cauchy hypersurfaces the slices $t=$ constant?


title: One-loop effective brane action

abstract:
  The one-loop effective action for a $p$ brane embedded in a $D=p+2$ Minkowski
spacetime in the static gauge is calculated. Rescaling the quantum fluctuation
by $\sqrt{-g_0}$ evaluated on the background brane leads to the one-loop
effective action expressed only in terms of infrared and ultraviolet divergent
geometric scalars. After the infrared divergences are absorbed into the quantum
fluctuation, there remains the finite number of ultraviolet divergences. This
implies that the $D=p+2$ Poincar\'{e} symmetry and the $D=p+1$ general
coordinate invariance are preserved in one-loop order.


title:
On the radial distribution of white dwarfs in the Galactic globular
  cluster Omega Cen

abstract:
  We present deep and accurate photometry (F435W, F625W, F658N) of the Galactic
Globular Cluster Omega Cen collected with the Advanced Camera for Surveys (ACS)
on board the Hubble Space Telescope (HST). We identified ~ 6,500 white dwarf
(WD)candidates and compared their radial distribution with that of Main
Sequence (MS) stars. We found a mild evidence that young WDs (0.1 < t < 0.6
Gyr) are less centrally concentrated when compared to MS stars in the magnitude
range 25 < F435W < 26.5.


title:
On the white dwarf cooling sequence of the globular cluster Omega
  Centauri

abstract:
  We present deep and precise photometry (F435, F625W, F658N) of Omega Cen
collected with the Advanced Camera for Surveys (ACS) on board the Hubble Space
Telescope (HST). We have identified ~ 6,500 white dwarf (WD) candidates, and
the ratio of WD and Main Sequence (MS) star counts is found to be at least a
factor of two larger than the ratio of CO-core WD cooling and MS lifetimes.
This discrepancy is not explained by the possible occurrence of a He-enhanced
stellar population, since the MS lifetime changes by only 15% when changing
from a canonical (Y=0.25) to a He-enhanced composition (Y=0.42). The presence
of some He-core WDs seems able to explain the observed star counts. The
fraction of He WDs required ranges from 10% to 80% depending on their mean mass
and it is at least five times larger than for field WDs. The comparison in the
Color Magnitude Diagram between theory and observations also supports the
presence of He WDs. Empirical evidence indicates that He WDs have been detected
in stellar systems hosting a large sample of extreme horizontal branch stars,
thus suggesting that a fraction of red giants might avoid the He-core flash.


title:
Observation of Exclusive Dijet Production at the Fermilab Tevatron
  p-pbar Collider

abstract:
  We present the first observation and cross section measurement of exclusive
dijet production in pbar-p interactions, pbar + p --> pbar + dijet + p. Using a
data sample of 310 pb-1 collected by the Run II Collider Detector at Fermilab
at sqrt{s}=1.96 TeV, exclusive cross sections for events with two jets of
transverse energy ET >= 10 GeV have been measured as a function of minimum
ET(jet). The exclusive signal is extracted from fits to data distributions
based on Monte Carlo simulations of expected dijet signal and background
shapes. The simulated background distribution shapes are checked in a study of
a largely independent data sample of 200 pb-1 of b-tagged jet events, where
exclusive dijet production is expected to be suppressed by the Jz=0 total
angular momentum selection rule. Results obtained are compared with theoretical
expectations, and implications for exclusive Higgs boson production at the pp
Large Hadron Collider at sqrt{s}=14 TeV are discussed.


title:
Correct Definition of the Poynting Vector in Electrically and
  Magnetically Polarizable Medium Reveals that Negative Refraction is
  Impossible

abstract:
  I compute from first principles the local heating rate $q$ (the amount of
electromagnetic energy converted to heat per unit time per unit volume) for
electromagnetic waves propagating in magnetically and electrically polarizable
media. I find that, in magnetic media, this rate has two separate
contributions, $q^{(V)}$ and $q^{(S)}$, the first coming from the volume of the
medium and the second from its surface. I argue that the second law of
thermodynamics requires that the volume contribution be positive and that this
requirement, in turn, prohibits negative refraction. This result holds for
active or passive media and in the presence of anisotropy and spatial
dispersion.


title:
Static Rouse Modes and Related Quantities: Corrections to Chain Ideality
  in Polymer Melts

abstract:
  Following the Flory ideality hypothesis intrachain and interchain excluded
volume interactions are supposed to compensate each other in dense polymer
systems. Multi-chain effects should thus be neglected and polymer conformations
may be understood from simple phantom chain models. Here we provide evidence
against this phantom chain, mean-field picture. We analyze numerically and
theoretically the static correlation function of the Rouse modes. Our numerical
results are obtained from computer simulations of two coarse-grained polymer
models for which the strength of the monomer repulsion can be varied, from full
excluded volume (`hard monomers') to no excluded volume (`phantom chains'). For
nonvanishing excluded volume we find the simulated correlation function of the
Rouse modes to deviate markedly from the predictions of phantom chain models.
This demonstrates that there are nonnegligible correlations along the chains in
a melt. These correlations can be taken into account by perturbation theory.
Our simulation results are in good agreement with these new theoretical
predictions.


title: Test of the Equivalence Principle Using a Rotating Torsion Balance

abstract:
  We used a continuously rotating torsion balance instrument to measure the
acceleration difference of beryllium and titanium test bodies towards sources
at a variety of distances. Our result Delta a=(0.6+/-3.1)x10^-15 m/s^2 improves
limits on equivalence-principle violations with ranges from 1 m to infinity by
an order of magnitude. The Eoetvoes parameter is eta=(0.3+/-1.8)x10^-13. By
analyzing our data for accelerations towards the center of the Milky Way we
find equal attractions of Be and Ti towards galactic dark matter, yielding
eta=(-4 +/- 7)x10^-5. Space-fixed differential accelerations in any direction
are limited to less than 8.8x10^-15 m/s^2 with 95% confidence.


title:
Linear water waves with vorticity: rotational features and particle
  paths

abstract:
  Steady linear gravity waves of small amplitude travelling on a current of
constant vorticity are found. For negative vorticity we show the appearance of
internal waves and vortices, wherein the particle trajectories are not any more
closed ellipses. For positive vorticity the situation resembles that of Stokes
waves, but for large vorticity the trajectories are affected.


title: Lattice Study of the Conformal Window in QCD-like Theories

abstract:
  Using lattice simulations, we study the extent of the conformal window for an
$\text{SU}(3)$ gauge theory with $N_f$ Dirac fermions in the fundamental
representation. We present evidence that the infrared behavior is conformal for
$12 \leq N_f \leq 16$, governed by an infrared fixed point, while confinement
and chiral symmetry breaking are present for $N_f \leq 8$.


title:
X-Atlas: An Online Archive of Chandra's Stellar High Energy Transmission
  Gratings Observations

abstract:
  The high-resolution X-ray spectroscopy made possible by the 1999 deployment
of the Chandra X-ray Observatory has revolutionized our understanding of
stellar X-ray emission. Many puzzles remain, though, particularly regarding the
mechanisms of X-ray emission from OB stars. Although numerous individual stars
have been observed in high-resolution, realizing the full scientific potential
of these observations will necessitate studying the high-resolution Chandra
dataset as a whole. To facilitate the rapid comparison and characterization of
stellar spectra, we have compiled a uniformly processed database of all stars
observed with the Chandra High Energy Transmission Grating (HETG). This
database, known as X-Atlas, is accessible through a web interface with
searching, data retrieval, and interactive plotting capabilities. For each
target, X-Atlas also features predictions of the low-resolution ACIS spectra
convolved from the HETG data for comparison with stellar sources in archival
ACIS images. Preliminary analyses of the hardness ratios, quantiles, and
spectral fits derived from the predicted ACIS spectra reveal systematic
differences between the high-mass and low-mass stars in the atlas and offer
evidence for at least two distinct classes of high-mass stars. A high degree of
X-ray variability is also seen in both high and low-mass stars, including
Capella, long thought to exhibit minimal variability. X-Atlas contains over 130
observations of approximately 25 high-mass stars and 40 low-mass stars and will
be updated as additional stellar HETG observations become public. The atlas has
recently expanded to non-stellar point sources, and Low Energy Transmission
Grating (LETG) observations are currently being added as well.


title: Fundamental Plasmid Strings and Black Rings

abstract:
  We construct excited states of fundamental strings that admit a semiclassical
description as rotating circular loops of string. We identify them with the
supergravity solutions for rotating dipole rings. The identification involves a
precise match of the mass, radius and angular momentum of the two systems.
Moreover, the degeneracy of the string state reproduces the parametric
dependence of the entropy in the supergravity description. When the solutions
possess two macroscopic angular momenta, they are better described as toroidal
configurations (tubular loops) instead of loops of string. We argue that the
decay of the string state can be interpreted as superradiant emission of quanta
from the ergoregion of the rotating ring.


title: An Accurate Distance to High-Velocity Cloud Complex C

abstract:
  We report an accurate distance of d = 10+/-2.5kpc to the high-velocity cloud
Complex C. Using high signal-to-noise Keck/HIRES spectra of two
horizontal-branch stars, we have detected CaII K absorption lines from the
cloud. Significant non-detections toward a further 3 stars yield robust lower
distance limits. The resulting HI mass of Complex C is 4.9^{+2.8}_{-2.2} x 10^6
Msun; a total mass of 8.2^{+4.6}_{-2.6} x 10^6 Msun is implied, after
corrections for helium and ionization. At 10kpc, Complex C has physical
dimensions 3x15 kpc, and if it is as thick as it is wide, then the average
density is log<n> ~ -2.5. We estimate the contribution of Complex C to the mass
influx may be as high as ~0.14 Msun/yr.


title: On fitting power laws to ecological data

abstract:
  Heavy-tailed or power-law distributions are becoming increasingly common in
biological literature. A wide range of biological data has been fitted to
distributions with heavy tails. Many of these studies use simple fitting
methods to find the parameters in the distribution, which can give highly
misleading results. The potential pitfalls that can occur when using these
methods are pointed out, and a step-by-step guide to fitting power-law
distributions and assessing their goodness-of-fit is offered.


title: Oscillons and Domain Walls

abstract:
  Oscillons, extremely long-lived localized oscillations of a scalar field, are
shown to be produced by evolving domain wall networks in quartic theory in two
spatial dimensions. We study the oscillons in frequency space using the
classical spectral function at zero momentum, and obtain approximate
information of their velocity distribution. In order to gain some insight onto
the dilute oscillon 'gas' produced by the domain walls, we prepare a denser gas
by filling the simulation volume with oscillons boosted in random directions.
We finish the study by revisiting collisions between oscillons and between an
oscillon and a domain wall, showing that in the latter case they can pass
straight through with minimal distortion.


title:
Infinite-Dimensional Symmetries of Two-Dimensional Coset Models Coupled
  to Gravity

abstract:
  In an earlier paper we studied the infinite-dimensional symmetries of
symmetric-space sigma models (SSMs) in a flat two-dimensional spacetime. Here,
we extend our investigation to the case of two-dimensional SSMs coupled to
gravity. These theories arise from the toroidal reduction of higher-dimensional
gravity and supergravities to two dimensions. We construct explicit expressions
for the symmetry transformations under the affine Kac-Moody extension $\hat G$
that arises when starting from a G/H coset model. We also construct further
explicit symmetry transformations that correspond to the modes L_n of a
Virasoro subalgebra with $n\ge -1$.


title: Upper Bounds for the Number of Hamiltonian Cycles

abstract:
  An upper bound for the number of Hamiltonian cycles of symmetric diagraphs is
established first in this paper, which is tighter than the famous Minc's bound
and the Br$\acute{e}$gman's bound. A transformation on graphs is proposed, so
that counting the number of Hamiltonian cycles of an undirected graph can be
done by counting the number of Hamiltonian cycles of its corresponding
symmetric directed graph. In this way, an upper bound for the number of
Hamiltonian cycles of undirected graphs is also obtained.


title: A folk model structure on omega-cat

abstract:
  We establish a model structure on the category of strict omega-categories.
The constructions leading to the model structure in question are expressed
entirely within the scope of omega-categories, building on a set of generating
cofibrations and a class of weak equivalences as basic items. All object are
fibrant while cofibrant objects are exactly the free ones. Our model structure
transfers to n-categories along right-adjoints, for each n, thus recovering the
known cases n = 1 and n = 2.


title:
Precision of Hubble constant derived using black hole binary absolute
  distances and statistical redshift information

abstract:
  Measured gravitational waveforms from black hole binary inspiral events
directly determine absolute luminosity distances. To use these data for
cosmology, it is necessary to independently obtain redshifts for the events,
which may be difficult for those without electromagnetic counterparts. Here it
is demonstrated that certainly in principle, and possibly in practice,
clustering of galaxies allows extraction of the redshift information from a
sample statistically for the purpose of estimating mean cosmological
parameters, without identification of host galaxies for individual events. We
extract mock galaxy samples from the 6th Data Release of the Sloan Digital Sky
Survey resembling those that would be associated with inspiral events of
stellar mass black holes falling into massive black holes at redshift z ~ 0.1
to 0.5. A simple statistical procedure is described to estimate a likelihood
function for the Hubble constant H_0: each galaxy in a LISA error volume
contributes linearly to the log likelihood for the source redshift, and the log
likelihood for each source contributes linearly to that of H_0. This procedure
is shown to provide an accurate and unbiased estimator of H_0. It is estimated
that a precision better than one percent in H_0 may be possible if the rate of
such events is sufficiently high, on the order of 20 to z = 0.5.


title:
Stable SUSY Breaking Model with O(10) eV Gravitino from Combined D-term
  Gauge Mediation and U(1)' Mediation

abstract:
  We show a calculable example of stable supersymmetry (SUSY) breaking models
with O(10) eV gravitino mass based on the combination of D-term gauge mediation
and U(1)' mediation. A potential problem of the negative mass squared for the
SUSY standard model (SSM) sfermions in the D-term gauge mediation is solved by
the contribution from the U(1)' mediation. On the other hand, the splitting
between the SSM gauginos and sfermions in the U(1)' mediation is circumvented
by the contributions from the D-term gauge mediation. Since the U(1)' mediation
does not introduce any new SUSY vacua, we achieve a completely stable model
under thermal effects. Our model, therefore, has no cosmological difficulty.


title:
Progress in methods to solve the Faddeev and Yakubovsky differential
  equations

abstract:
  We shortly recall the derivation of the Faddeev-Yakubovsky differential
equations and point out their main advantages. Then we give a review of the
numerical approaches used to solve the bound-state and scattering problems for
the three- and four-body systems based on these equations. A particular
attention is payed to the latest developments.


title: Analytic properties of different unitarization schemes

abstract:
  The analytic properties of the eikonal and U-matrix unitarization schemes are
examined. It is shown that the basic properties of these schemes are identical.
Both can fill the full circle of unitarity, and both can lead to standard and
non-standard asymptotic relations for the ratio of the elastic cross section to
the total cross section. The relation between the phases of the unitarized
amplitudes in each scheme is examined, and it is shown that demanding
equivalence of the two schemes leads to a bound on the phase in the U-matrix
scheme.


title: Filtrations

abstract:
  In this article, we define the notion of a filtration and then give the basic
theorems on initial and progressive enlargements of filtrations.


title: Statistics of orbital entanglement production in quantum-chaotic dots

abstract:
  The production of orbitally entangled electrons in quantum-chaotic dots is
investigated from a statistical point of view. The degree of entanglement is
quantified through the concurrence and the entanglement of formation. We
calculate the complete statistical distributions of the entanglement measures
by using random matrix theory. Simple analytical expressions are provided for
the concurrence distributions. We identify clear signatures of time-reversal
invariance in the production of entanglement at the level of the
entanglement-measure distributions, such as the ability of producing maximally
entangled (Bell) states, which passed unnoticed in previous works where only
the first two moments of the distributions were studied.


title:
Theory of electronic transport through a triple quantum dot in the
  presence of magnetic field

abstract:
  Theory of electronic transport through a triangular triple quantum dot
subject to a perpendicular magnetic field is developed using a tight binding
model. We show that magnetic field allows to engineer degeneracies in the
triple quantum dot energy spectrum. The degeneracies lead to zero electronic
transmission and sharp dips in the current whenever a pair of degenerate states
lies between the chemical potential of the two leads. These dips can occur with
a periodicity of one flux quantum if only two levels contribute to the current
or with half flux quantum if the three levels of the triple dot contribute. The
effect of strong bias voltage and different lead-to-dot connections on
Aharonov-Bohm oscillations in the conductance is also discussed.


title: Mixing Times in Quantum Walks on the Hypercube

abstract:
  The mixing time of a discrete-time quantum walk on the hypercube is
considered. The mean probability distribution of a Markov chain on a hypercube
is known to mix to a uniform distribution in time O(n log n). We show that the
mean probability distribution of a discrete-time quantum walk on a hypercube
mixes to a (generally non-uniform) distribution pi(x) in time O(n) and the
stationary distribution is determined by the initial state of the walk. An
explicit expression for pi(x) is derived for the particular case of a symmetric
walk. These results are consistent with those obtained previously for a
continuous-time quantum walk. The effect of decoherence due to randomly
breaking links between connected sites in the hypercube is also considered. We
find that the probability distribution mixes to the uniform distribution as
expected. However, the mixing time has a minimum at a critical decoherence rate
$p \approx 0.1$. A similar effect was previously reported for the QW on the
N-cycle with decoherence from repeated measurements of position. A controlled
amount of decoherence helps to obtain--and preserve--a uniform distribution
over the $2^n$ sites of the hypercube in the shortest possible time.


title:
A Class of Soliton Solutions for the N=2 Super mKdV/Sinh-Gordon
  Hierarchy

abstract:
  Employing the Hirota's method, a class of soliton solutions for the N=2 super
mKdV equations is proposed in terms of a single Grassmann parameter. Such
solutions are shown to satisfy two copies of N=1 supersymmetric mKdV equations
connected by nontrivial algebraic identities. Using the super Miura
transformation, we obtain solutions of the N=2 super KdV equations. These are
shown to generalize solutions derived previously. By using the mKdV/sinh-Gordon
hierarchy properties we generate the solutions of the N=2 super sinh-Gordon as
well.


title: Linear b-Gauges for Open String Fields

abstract:
  Motivated by Schnabl's gauge choice, we explore open string perturbation
theory in gauges where a linear combination of antighost oscillators
annihilates the string field. We find that in these linear b-gauges different
gauge conditions are needed at different ghost numbers. We derive the full
propagator and prove the formal properties which guarantee that the Feynman
diagrams reproduce the correct on-shell amplitudes. We find that these
properties can fail due to the need to regularize the propagator, and identify
a large class of linear b-gauges for which they hold rigorously. In these
gauges the propagator has a non-anomalous Schwinger representation and builds
Riemann surfaces by adding strip-like domains. Projector-based gauges, like
Schnabl's, are not in this class of gauges but we construct a family of regular
linear b-gauges which interpolate between Siegel gauge and Schnabl gauge.


title:
The Genus Two Partition Function for Free Bosonic and Lattice Vertex
  Operator Algebras

abstract:
  We define the $n$-point function for a vertex operator algebra on a genus two
Riemann surface in two separate sewing schemes where either two tori are sewn
together or a handle is sewn to one torus. We explicitly obtain closed formulas
for the genus two partition function for the Heisenberg free bosonic string and
lattice vertex operator algebras in both sewing schemes. We prove that the
partition functions are holomorphic in the sewing parameters on given suitable
domains and describe their modular properties. Finally, we show that the
partition functions cannot be equal in the neighborhood of a two-tori
degeneration point where they can be explicitly compared.


title: Modular unit and cuspidal divisor class groups of X_1(N)

abstract:
  In this article, we consider the group $F_1^\infty(N)$ of modular
  units on $X_1(N)$ that have divisors supported on the cusps lying
  over $\infty$ of $X_0(N)$, called the $\infty$-cusps. For each
  positive integer $N$, we will give an explicit basis for the group
  $F_1^\infty(N)$. This enables us to compute the group structure of
  the rational torsion subgroup $C_1^\infty(N)$ of the Jacobian
  $J_1(N)$ of $X_1(N)$ generated by the differences of the
  $\infty$-cusps. In addition, based on our numerical
  computation, we make a conjecture on the structure of the
  $p$-primary part of $C_1^\infty(p^n)$ for a regular prime $p$.


title: On The Leptons Masses

abstract:
  In this paper we present a connection between the results obtained from a
semiclassical study of a relativistic, two-body system, and the leptons masses.
Some possible consequences are also discussed.


title: Overpartitions and class numbers of binary quadratic forms

abstract:
  We show that the Zagier-Eisenstein series shares its non-holomorphic part
with certain weak Maass forms whose holomorphic parts are generating functions
for overpartition rank differences. This has a number of consequences,
including exact formulas, asymptotics, and congruences for the rank differences
as well as $q$-series identities of the mock theta type.


title:
Topologically unique maximal elementary Abelian group actions on compact
  oriented surfaces

abstract:
  We determine all finite maximal elementary abelian group actions on compact
oriented surfaces of genus $\sigma\geq 2$ which are unique up to topological
equivalence. For certain special classes of such actions, we determine group
extensions which also define unique actions. In addition, we explore in detail
one of the families of such surfaces considered as compact Riemann surfaces and
tackle the classical problem of constructing defining equations.


title: Hadron Properties and Dyson-Schwinger Equations

abstract:
  An overview of the theory and phenomenology of hadrons and QCD is provided
from a Dyson-Schwinger equation viewpoint. Following a discussion of the
definition and realisation of light-quark confinement, the nonperturbative
nature of the running mass in QCD and inferences from the gap equation relating
to the radius of convergence for expansions of observables in the current-quark
mass are described. Some exact results for pseudoscalar mesons are also
highlighted, with details relating to the U_A(1) problem, and calculated masses
of the lightest J=0,1 states are discussed. Studies of nucleon properties are
recapitulated upon and illustrated: through a comparison of the ln-weighted
ratios of Pauli and Dirac form factors for the neutron and proton; and a
perspective on the contribution of quark orbital angular momentum to the spin
of a nucleon at rest. Comments on prospects for the future of the study of
quarks in hadrons and nuclei round out the contribution.


title:
High-precision covariant one-boson-exchange potentials for np scattering
  below 350 MeV

abstract:
  Using the Covariant Spectator Theory (CST), we have found One-Boson-Exchange
(OBE) potentials that fit the 2006 world np data below 350 MeV with a
\chi^2/N_data very close to 1, for a total of 3788 data. Our potentials have
significantly fewer adjustable parameters than previous high-precision
potentials, and they also reproduce the experimental triton binding energy
without introducing additional irreducible three-nucleon forces.


title: Dilepton production and off-shell transport dynamics at SIS energies

abstract:
  Dilepton production in nucleus-nucleus collisions at 1-2 A GeV as well as in
elementary pp and pd reactions is studied within the microscopic HSD transport
approach which includes the off-shell dynamics of vector mesons explicitly. The
study addresses additionally the production of $\pi^0$ and $\eta$ mesons since
their Dalitz decays provide a sizeable contribution to the dilepton invariant
mass spectra up to about 0.5 GeV. Our transport results agree with the TAPS
experimental data on $\pi$ and $\eta$ multiplicities in C+C collisions from 0.8
to 2 A GeV. We find that the 'DLS-puzzle' - which addresses an underestimation
of the $e^+e^-$ yield in the mass range from 0.2 to 0.5 GeV in C+C and Ca+Ca
collisions - may be solved when incorporating a stronger bremsstrahlung
contribution in line with recent OBE calculations. Moreover, the HSD results
with 'enhanced' bremsstrahlung cross sections agree very well with the HADES
experimental data for the dilepton mass spectra for C+C at 1 and 2 A GeV,
especially when including a collisional broadening in the vector-meson spectral
functions. Detailed predictions for dilepton spectra from pp and pn/pd
reactions at 1.25 GeV, 2.2 GeV and 3.5 GeV are presented which will allow to
verify/falsify the larger bremsstrahlung contributions from the experimental
side in the near future.


title:
Controlled Synchronization of One Class of Nonlinear Systems under
  Information Constraints

abstract:
  Output feedback controlled synchronization problems for a class of nonlinear
unstable systems under information constraints imposed by limited capacity of
the communication channel are analyzed. A binary time-varying coder-decoder
scheme is described and a theoretical analysis for multi-dimensional
master-slave systems represented in Lurie form (linear part plus nonlinearity
depending only on measurable outputs) is provided. An output feedback control
law is proposed based on the Passification Theorem. It is shown that the
synchronization error exponentially tends to zero for sufficiantly high
transmission rate (channel capacity). The results obtained for synchronization
problem can be extended to tracking problems in a straightforward manner, if
the reference signal is described by an {external} ({exogenious}) state space
model. The results are applied to controlled synchronization of two chaotic
Chua systems via a communication channel with limited capacity.


title:
In Pursuit of LSST Science Requirements: A Comparison of Photometry
  Algorithms

abstract:
  We have developed an end-to-end photometric data processing pipeline to
compare current photometric algorithms commonly used on ground-based imaging
data. This testbed is exceedingly adaptable, and enables us to perform many
research and development tasks, including image subtraction and co-addition,
object detection and measurements, the production of photometric catalogs, and
the creation and stocking of database tables with time-series information. This
testing has been undertaken to evaluate existing photometry algorithms for
consideration by a next-generation image processing pipeline for the Large
Synoptic Survey Telescope (LSST). We outline the results of our tests for four
packages: The Sloan Digital Sky Survey's (SDSS) Photo package, Daophot and
Allframe, DoPhot, and two versions of Source Extractor (SExtractor). The
ability of these algorithms to perform point-source photometry, astrometry,
shape measurements, star-galaxy separation, and to measure objects at low
signal-to-noise is quantified. We also perform a detailed crowded field
comparison of Daophot and Allframe, and profile the speed and memory
requirements in detail for SExtractor. We find that both Daophot and Photo are
able to perform aperture photometry to high enough precision to meet LSST's
science requirements, and less adequately at PSF-fitting photometry. Photo
performs the best at simultaneous point and extended-source shape and
brightness measurements. SExtractor is the fastest algorithm, and recent
upgrades in the software yield high-quality centroid and shape measurements
with little bias towards faint magnitudes. Allframe yields the best photometric
results in crowded fields.


title: Quantum nanomagnets and nuclear spins: an overview

abstract:
  This mini-review presents a simple and accessible summary on the fascinating
physics of quantum nanomagnets coupled to a nuclear spin bath. These chemically
synthesized systems are an ideal test ground for the theories of decoherence in
mesoscopic quantum degrees of freedom, when the coupling to the environment is
local and not small. We shall focus here on the most striking quantum
phenomenon that occurs in such nanomagnets, namely the tunneling of their giant
spin through a high anisotropy barrier. It will be shown that perturbative
treatments must be discarded, and replaced by a more sophisticated formalism
where the dynamics of the nanomagnet and the nuclei that couple to it are
treated together from the beginning. After a critical review of the theoretical
predictions and their experimental verification, we continue with a set of
experimental results that challenge our present understanding, and outline the
importance of filling also this last gap in the theory.


title:
BPS Explained II: Calculating the Equilibration Rate in the Extreme
  Quantum Limit

abstract:
  This is the second in a series of two lectures on the technique of
dimensional continuation, a new method for analytically calculating certain
energy transport quantities in a weakly to moderately coupled plasma. Recently,
this method was employed by Brown, Preston, and Singleton (BPS) to calculate
the electron-ion temperature equilibration rate and the charged particle
stopping power to leading and next-to-leading order in the plasma coupling. In
this lecture, I develop the framework further, and then explicitly calculate
the electron-ion temperature equilibration rate in the high temperature limit.
This method captures all short and long distance physics to second order in the
plasma coupling. This analytic perturbative technique is applicable for
ignition in inertial confinement fusion and for other processes in hot a weakly
coupled plasma.


title: Validity of the "sharp-kink approximation" for water and other fluids

abstract:
  The contact angle of a liquid droplet on a solid surface is a direct measure
of fundamental atomic-scale forces acting between liquid molecules and the
solid surface. In this work, the validity is assessed of a simple equation,
which approximately relates the contact angle of a liquid on a surface to its
density, its surface tension, and the effective molecule-surface potential.
This equation is derived in the sharp-kink approximation, where the density
profile of the liquid is assumed to drop precipitously within one molecular
diameter of the substrate. It is found that this equation satisfactorily
reproduces the temperature-dependence of the contact angle for helium on alkali
metal surfaces. The equation also seems be applicable to liquids such as water
on solid surfaces such as gold and graphite, based on a comparison of predicted
and measured contact angles near room-temperature. Nevertheless, we conclude
that, to fully test the equation's applicability to fluids such as water, it
remains necessary to measure the contact angle's temperature-dependence. We
hypothesize that the effects of electrostatic forces can increase with
temperature, potentially driving the wetting temperature much higher and closer
to the critical point, or lower, closer to room temperature, than predicted
using current theories.


title: The Natural Philosophy of Kazuo Kondo

abstract:
  Kazuo Kondo (1911-2001) was Chair of the Department of Mathematical
Engineering at the University of Tokyo, Japan. Over a period of 50 years, he
and a few colleagues wrote and published a voluminous series of papers and
monographs on the applications of analytical geometry within a diverse range of
subjects in the natural sciences. Inspired by Otto Fischer's attempt at a
quaternionic unified theory in the late 1950's he adopted the mathematics of
the revered Akitsugu Kawaguchi to produce his own speculative unified theory.
The theory appears to successfully apply Kawaguchi's mathematics to the full
range of natural phenomena, from the structure of fundamental particles to the
geometry of living beings. The theories are testable and falsifiable. Kondo and
his theories are now almost completely unknown and this paper serves as the
barest introduction to his work


title: Noncommutative corrections to classical black holes

abstract:
  We calculate leading long-distance noncommutative corrections to the
classical Schwarzschild black hole which is sourced by a massive noncommutative
scalar field. The energy-momentum tensor is taken up to ${\cal O}(\ell^4)$ in
noncommutative parameter, and is treated in semiclassical (tree level)
approximation. These noncommutative corrections can dominate classical
post-post-Newtonian corrections providing $\ell > 1/M_P$, however, they are
still too small to be observable in present-day experiments.


title: Free curves and periodic points for torus homeomorphisms

abstract:
  We study the relationship between free curves and periodic points for torus
homeomorphisms in the homotopy class of the identity. By free curve we mean a
homotopically nontrivial simple closed curve that is disjoint from its image.
We prove that every rational point in the rotation set is realized by a
periodic point provided that there is no free curve and the rotation set has
empty interior. This gives a topological version of a theorem of Franks. Using
this result, and inspired by a theorem of Guillou, we prove a version of the
Poincar\'e-Birkhoff Theorem for torus homeomorphisms: in the absence of free
curves, either there is a fixed point or the rotation set has nonempty
interior.


title:
Local moment, itinerancy and deviation from Fermi liquid behavior in
  Na$_x$CoO$_2$ for $0.71 \leq x \leq 0.84$

abstract:
  Here we report the observation of Fermi surface (FS) pockets via the
Shubnikov de Haas effect in Na$_x$CoO$_2$ for $x = 0.71$ and 0.84,
respectively. Our observations indicate that the FS expected for each compound
intersects their corresponding Brillouin zones, as defined by the previously
reported superlattice structures, leading to small reconstructed FS pockets,
but only if a precise number of holes per unit cell is \emph{localized}. For
$0.71 \leq x < 0.75$ the coexistence of itinerant carriers and localized $S
=1/2$ spins on a paramagnetic triangular superlattice leads at low temperatures
to the observation of a deviation from standard Fermi-liquid behavior in the
electrical transport and heat capacity properties, suggesting the formation of
some kind of quantum spin-liquid ground state.


title: Quasinormal modes and phase Transition of black holes

abstract:
  We have studied the scalar field as well as the fermonic field perturbations
in the background of the massless BTZ black holes. Comparing with the
perturbation results in the generic nonrotating BTZ black hole background, we
found that the massless BTZ hole contains only normal modes in the
perturbations. We argued that this special property reflects that the massless
BTZ black hole is a different phase from that of the generic nonrotating BTZ
hole.


title: The instability of intersecting fuzzy spheres

abstract:
  We discuss the classical and quantum stability of general configurations
representing many fuzzy spheres in dimensionally reduced
Yang-Mills-Chern-Simons models with and without supersymmetry. By performing
one-loop perturbative calculations around such configurations, we find that
intersecting fuzzy spheres are classically unstable in the class of models
studied in this paper. We also discuss the large-N limit of the one-loop
effective action as a function of the distance of fuzzy spheres. This shows, in
particular, that concentric fuzzy spheres with different radii, which are
identified with the 't Hooft-Polyakov monopoles, are perturbatively stable in
the bosonic model and in the D=10 supersymmetric model.


title:
Bridging the primordial A=8 divide with Catalyzed Big Bang
  Nucleosynthesis

abstract:
  Catalysis of nuclear reactions by metastable charged particles X^- opens the
possibility for primordial production of elements with A>7. We calculate the
abundance of ^9Be, where synthesis is mediated by the formation of (^8Be X^-)
bound states, finding a dramatic enhancement over the standard BBN prediction:
^9Be/^1H = 10^{-13}\times(Y_X/10^{-5}). Thus observations of ^9Be abundances at
low metallicity offers a uniquely sensitive probe of many particle physics
models that predict X^-, including variants of supersymmetric models. Comparing
the catalytically-enhanced abundances of primordial ^6Li and ^9Be, we find the
relation ^9Be/^6Li = (2-5)\times 10^{-3} that holds over a wide range of X^-
abundances and lifetimes.


title: Central Limit Theorem for Branching Random Walks in Random Environment

abstract:
  We consider branching random walks in $d$-dimensional integer lattice with
time-space i.i.d. offspring distributions. When $d \ge 3$ and the fluctuation
of the environment is well moderated by the random walk, we prove a central
limit theorem for the density of the population, together with upper bounds for
the density of the most populated site and the replica overlap. We also discuss
the phase transition of this model in connection with directed polymers in
random environment.


title: Localization for Branching Random Walks in Random Environment

abstract:
  We consider branching random walks in $d$-dimensional integer lattice with
time-space i.i.d. offspring distributions. This model is known to exhibit a
phase transition: If $d \ge 3$ and the environment is "not too random", then,
the total population grows as fast as its expectation with strictly positive
probability. If,on the other hand, $d \le 2$, or the environment is ``random
enough", then the total population grows strictly slower than its expectation
almost surely. We show the equivalence between the slow population growth and a
natural localization property in terms of "replica overlap". We also prove a
certain stronger localization property, whenever the total population grows
strictly slower than its expectation almost surely.


title: Extended symmetrical classical electrodynamics

abstract:
  In the present article, we discuss a modification of classical
electrodynamics in which ``ordinary'' point charges are absent. The modified
equations contain additional terms describing the induced charges and currents.
The densities of the induced charges and currents depend on the vector k and
the vectors of the electromagnetic field E and B. It is shown that the vectors
E and B can be defined in terms of two 4-potentials and the components of k are
the components of the 4-tensor of the third rank. The Lagrangian of modified
electrodynamics is defined. The conditions are derived at which only one
4-potential determines the behavior of the electromagnetic field. It is also
shown that static modified electrodynamics can describe the electromagnetic
field in the inner region of the electric monopole. In the outer region of the
electric monopole the electric field is governed by the Maxwell equations. It
follows from boundary conditions at the interface between the inner and outer
regions of the monopole that the vector k has a discrete spectrum. The electric
and magnetic fields, energy and angular momentum of the monopole are found for
different eigenvalues of k.


title: Note on the Lattice Fermion Chiral Symmetry Group

abstract:
  The group structure of the variant chiral symmetry discovered by Luscher in
the Ginsparg-Wilson description of lattice chiral fermions is analyzed. It is
shown that the group contains an infinite number of linearly independent
symmetry generators, and the Lie algebra is given explicitly. CP is an
automorphism of the chiral group, and the CP transformation properties of the
symmetry generators is found. Features of the currents associated with these
symmetries are discussed, including the fact that some different, non-commuting
symmetry generators lead to the same Noether current. These strange features
occur in all implementations of lattice fermions based on the Ginsparg-Wilson
relation, including overlap, domain-wall, and perfect-action chiral fermions.
The conclusions are illustrated in a solvable example, free overlap fermions.


title: On a construction of self-dual gauge fields in seven dimensions

abstract:
  We consider gauge fields associated with a semisimple Malcev algebra. We
construct a gauge-invariant Lagrangian and found a solution of modified
Yang-Mills equations in seven dimensions.


title: Equations of States in Singular Statistical Estimation

abstract:
  Learning machines which have hierarchical structures or hidden variables are
singular statistical models because they are nonidentifiable and their Fisher
information matrices are singular. In singular statistical models, neither the
Bayes a posteriori distribution converges to the normal distribution nor the
maximum likelihood estimator satisfies asymptotic normality. This is the main
reason why it has been difficult to predict their generalization performances
from trained states. In this paper, we study four errors, (1) Bayes
generalization error, (2) Bayes training error, (3) Gibbs generalization error,
and (4) Gibbs training error, and prove that there are mathematical relations
among these errors. The formulas proved in this paper are equations of states
in statistical estimation because they hold for any true distribution, any
parametric model, and any a priori distribution. Also we show that Bayes and
Gibbs generalization errors are estimated by Bayes and Gibbs training errors,
and propose widely applicable information criteria which can be applied to both
regular and singular statistical models.


title: Complex Wave Numbers in the Vicinity of the Schwarzschild Event Horizon

abstract:
  This paper is devoted to investigate the cold plasma wave properties outside
the event horizon of the Schwarzschild planar analogue. The dispersion
relations are obtained from the corresponding Fourier analyzed equations for
non-rotating and rotating, non-magnetized and magnetized backgrounds. These
dispersion relations provide complex wave numbers. The wave numbers are shown
in graphs to discuss the nature and behavior of waves and the properties of
plasma lying in the vicinity of the Schwarzschild event horizon.


title: Effects of Schwarzschild Geometry on Isothermal Plasma Wave Dispersion

abstract:
  The behavior of isothermal plasma waves has been analyzed near the
Schwarzschild horizon. We consider a non-rotating background with
non-magnetized and magnetized plasmas. The general relativistic
magnetohydrodynamical equations for the Schwarzschild planar analogue spacetime
with an isothermal state of the plasma are formulated. The perturbed form of
these equations is linearized and Fourier analyzed by introducing simple
harmonic waves. The determinant of these equations in each case leads to a
complex dispersion relation, which gives complex values of the wave number.
This has been used to discuss the nature of the waves and their characteristics
near the horizon.


title: On the structure of QCD confining string

abstract:
  This paper had been withdrawn because the prime reported effect had not been
confirmed in further investigations (see arXiv:0812.4488 [hep-lat]).


title:
Photoproduction of neutral kaons on the liquid deuterium target in the
  threshold region

abstract:
  The photoproduction process of neutral kaons on a liquid deuterium target is
investigated near the threshold region, Egamma = 0.8-1.1 GeV. K0 events are
reconstructed from positive and negative pions, and differential cross sections
are derived. Experimental momentum spectra are compared with those calculated
in the spectator model using a realistic deuteron wave function. Elementary
amplitudes as given by recent isobar models and a simple phenomenological model
are used to study the effect of the new data on the angular behavior of the
elementary cross section. The data favor a backward-peaked angular distribution
of the elementary n(gamma,K0)Lambda process, which provides additional
constraints on current models of kaon photoproduction. The present study
demonstrates that the n(gamma,K0)Lambda reaction can provide key information on
the mechanism of the photoproduction of strangeness.


title: The qqbar S-wave axial-vector mesons in the covariant U~(12)-scheme

abstract:
  We study the properties of axial vector mesons a1 and b1 as relativistic
S-wave states which are predicted in the U~(12)-scheme, through the analyses of
their radiative and pionic decays. Specifically, partial widths of the strong
a1 (b1) -> rho(omega) pi processes, their D/S-wave amplitude ratios, and
radiative transition widths of a1(b1) -> pi gamma processes are calculated by
using a simple decay interaction model, and made a comparison with the
respective experimental values.


title: An Empirical Study of Immune System Based On Bipartite Network

abstract:
  Immune system is the most important defense system to resist human pathogens.
In this paper we present an immune model with bipartite graphs theory. We
collect data through COPE database and construct an immune cell- mediators
network. The act degree distribution of this network is proved to be power-law,
with index of 1.8. From our analysis, we found that some mediators with high
degree are very important mediators in the process of regulating immune
activity, such as TNF-alpha, IL-8, TNF-alpha receptors, CCL5, IL-6, IL-2
receptors, TNF-beta receptors, TNF-beta, IL-4 receptors, IL-1 beta, CD54 and so
on. These mediators are important in immune system to regulate their activity.
We also found that the assortative of the immune system is -0.27. It reveals
that our immune system is non-social network. Finally we found similarity of
the network is 0.13. Each two cells are similar to small extent. It reveals
that many cells have its unique features. The results show that this model
could describe the immune system comprehensive.


title:
A practical illustration of the importance of realistic individualized
  treatment rules in causal inference

abstract:
  The effect of vigorous physical activity on mortality in the elderly is
difficult to estimate using conventional approaches to causal inference that
define this effect by comparing the mortality risks corresponding to
hypothetical scenarios in which all subjects in the target population engage in
a given level of vigorous physical activity. A causal effect defined on the
basis of such a static treatment intervention can only be identified from
observed data if all subjects in the target population have a positive
probability of selecting each of the candidate treatment options, an assumption
that is highly unrealistic in this case since subjects with serious health
problems will not be able to engage in higher levels of vigorous physical
activity. This problem can be addressed by focusing instead on causal effects
that are defined on the basis of realistic individualized treatment rules and
intention-to-treat rules that explicitly take into account the set of treatment
options that are available to each subject. We present a data analysis to
illustrate that estimators of static causal effects in fact tend to
overestimate the beneficial impact of high levels of vigorous physical activity
while corresponding estimators based on realistic individualized treatment
rules and intention-to-treat rules can yield unbiased estimates. We emphasize
that the problems encountered in estimating static causal effects are not
restricted to the IPTW estimator, but are also observed with the
$G$-computation estimator, the DR-IPTW estimator, and the targeted MLE. Our
analyses based on realistic individualized treatment rules and
intention-to-treat rules suggest that high levels of vigorous physical activity
may confer reductions in mortality risk on the order of 15-30%, although in
most cases the evidence for such an effect does not quite reach the 0.05 level
of significance.


title: A Collaboration Network Model Of Cytokine-Protein Network

abstract:
  Complex networks provide us a new view for investigation of immune systems.
In this paper we collect data through STRING database and present a model with
cooperation network theory. The cytokine-protein network model we consider is
constituted by two kinds of nodes, one is immune cytokine types which can act
as acts, other one is protein type which can act as actors. From act degree
distribution that can be well described by typical SPL -shifted power law
functions, we find that
HRAS.TNFRSF13C.S100A8.S100A1.MAPK8.S100A7.LIF.CCL4.CXCL13 are highly
collaborated with other proteins. It reveals that these mediators are important
in cytokine-protein network to regulate immune activity. Dyad act degree
distribution is another important property to generalized collaboration
network. Dyad is two proteins and they appear in one cytokine collaboration
relationship. The dyad act degree distribution can be well described by typical
SPL functions. The length of the average shortest path is 1.29. These results
show that this model could describe the cytokine-protein collaboration
preferably


title: Least Area Planes in Hyperbolic 3-Space are Properly Embedded

abstract:
  We show that if P is an embedded least area (area minimizing) plane in
hyperbolic 3-space whose asymptotic boundary is a simple closed curve with at
least one smooth point, then P is properly embedded.


title: Quasi-kernels and quasi-sinks in infinite graphs

abstract:
  Given a directed graph G=(V,E) an independent set A of the vertices V is
called quasi-kernel (quasi-sink) iff for each point v there is a path of length
at most 2 from some point of A to v (from v to some point of A). Every finite
directed graph has a quasi-kernel. The plain generalization for infinite graphs
fails, even for tournaments. We investigate the following conjecture here: for
any digraph G=(V,E) there is a a partition (V_0,V_1) of the vertex set such
that the induced subgraph G[V_0] has a quasi-kernel and the induced subgraph
G[V_1] has a quasi-sink.


title:
On the Existence of Light-Scalar Mesons kappa(800) and kappa'(1150): The
  U~(12) Scheme and BES II Data

abstract:
  We present that there should exist a light strange-scalar meson kappa', in
addition to the kappa(800), which has a mass around 1.1-1.2 GeV, a rather
narrow width, and couples strongly to kappa(800)sigma(600) (Kpipipi) but weakly
to Kpi, based upon the U~(12)-classification scheme of hadrons and BES II data
on J/psi -> barK*(892)0K+pi- decay.


title:
Modules with Finite Cousin Cohomologies Have Uniform Local Cohomological
  Annihilators

abstract:
  Let A be a Noetherian ring. It is shown that any finite A--module M of finite
Krull dimension with finite Cousin complex cohomologies has a uniform local
cohomological annihilator. The converse is also true for a finite module M
satisfying (S_2) which is over a local ring with Cohen--Macaulay formal fibres.


title:
An Improved Error Bound for Multiquadric and Inverse Multiquadric
  Interpolation

abstract:
  A new error bound which is better than the current exponential-type error
bound is presented in this paper.


title:
Determinants on von Neumann algebras, Mahler measures and Ljapunov
  exponents

abstract:
  For an ergodic measure preserving action on a probability space, consider the
corresponding crossed product von Neumann algebra. We calculate the
Fuglede-Kadison determinant for a class of operators in this von Neumann
algebra in terms of the Ljapunov exponents of an associated measurable cocycle.
The proof is based on recent work of Dykema and Schultz. As an application one
obtains formulas for the Fuglede-Kadison determinant of noncommutative
polynomials in the von Neumann algebra of the discrete Heisenberg group. These
had been previously obtained by Lind and Schmidt via entropy considerations.


title: Bose-Einstein Correlations in Multihadron Events at LEP

abstract:
  Bose-Einstein correlations in pairs of identical particles were analyzed in
e+ e- multihadron annihilations at ~91.2 GeV at LEP. The first studies involved
identical charged pions and the emitting source size was determined. Then the
study of charged kaons suggested that the radius depends on the mass of the
emitted particles. Subsequenty the dependence of the source radius on the event
multiplicity was analyzed. The study of the correlations in neutral pions and
neutral kaons extended these concepts to neutral particles. The shape of the
source was analyzed in 3 dimensions and was found not to be spherically
symmetric. In recent studies at LEP the correlations were analyzed in intervals
of the average pair transverse momentum and of the pair rapidity to study the
correlations between the pion production points and their momenta
(position-momentum correlations). The latest e+ e- data are consistent with an
expanding source.


title: Integral Lattices of the SU(2)-TQFT-Modules

abstract:
  We find bases for naturally defined lattices over certain rings of integers
in the SU(2)-TQFT-theory modules of surfaces. We consider the TQFT where the
Kauffman's A variable is a root of unity of order four times an odd prime. As
an application, we show that the Frohman Kania-Bartoszynska ideal invariant for
3-manifolds with boundary using the SU(2)-TQFT-theory is equal to the product
of the ideals using the 2^{'}-theory and the SO(3)-TQFT-theory under a certain
change of coefficients.


title:
Disclosing hidden information in the quantum Zeno effect: Pulsed
  measurement of the quantum time of arrival

abstract:
  Repeated measurements of a quantum particle to check its presence in a region
of space was proposed long ago [G. R. Allcock, Ann. Phys. {\bf 53}, 286 (1969)]
as a natural way to determine the distribution of times of arrival at the
orthogonal subspace, but the method was discarded because of the quantum Zeno
effect: in the limit of very frequent measurements the wave function is
reflected and remains in the original subspace. We show that by normalizing the
small bits of arriving (removed) norm, an ideal time distribution emerges in
correspondence with a classical local-kinetic-energy distribution.


title:
Ram pressure stripping of disc galaxies orbiting in clusters. II.
  Galactic wakes

abstract:
  We present 3D hydrodynamical simulations of ram pressure stripping of a disc
galaxy orbiting in a galaxy cluster. In this paper, we focus on the properties
of the galaxies' tails of stripped gas. The galactic wakes show a flaring
width, where the flaring angle depends on the gas disc's cross-section with
respect to the galaxy's direction of motion. The velocity in the wakes shows a
significant turbulent component of a few 100 km/s. The stripped gas is
deposited in the cluster rather locally, i.e. within ~150 kpc from where it was
stripped. We demonstrate that the most important quantity governing the tail
density, length and gas mass distribution along the orbit is the galaxy's mass
loss per orbital length. This in turn depends on the ram pressure as well as
the galaxy's orbital velocity. For a sensitivity limit of ~10^19 cm^-2 in
projected gas density, we find typical tail lengths of 40 kpc. Such long tails
are seen even at large distances (0.5 to 1 Mpc) from the cluster centre. At
this sensitivity limit, the tails show little flaring, but a width similar to
the gas disc's size. Morphologically, we find good agreement with the HI tails
observed in the Virgo cluster by Chung et al. (2007). However, the observed
tails show a much smaller velocity width than predicted from the simulation.
The few known X-ray and H$\alpha$ tails are generally much narrower and much
straighter than the tails in our simulations. Thus, additional physics like a
viscous ICM, the influence of cooling and tidal effects may be needed to
explain the details of the observations. We discuss the hydrodynamical drag as
a heat source for the ICM but conclude that it is not likely to play an
important role, especially not in stopping cooling flows.


title: Planar Limit of Orientifold Field Theories and Emergent Center Symmetry

abstract:
  We consider orientifold field theories (i.e. SU(N) Yang--Mills theories with
fermions in the two-index symmetric or antisymmetric representations) on R3xS1
where the compact dimension can be either temporal or spatial. These theories
are planar equivalent to supersymmetric Yang--Mills. The latter has Z_N center
symmetry. The famous Polyakov criterion establishing confinement-deconfinement
phase transition as that from Z_N symmetric to Z_N broken phase applies. At the
Lagrangian level the orientifold theories have at most a Z_2 center. We discuss
how the full Z_N center symmetry dynamically emerges in the orientifold
theories in the limit N-->infinity. In the confining phase the manifestation of
this enhancement is the existence of stable k-strings in the large-N limit of
the orientifold theories. These strings are identical to those of
supersymmetric Yang--Mills theories. We argue that critical temperatures (and
other features) of the confinement-deconfinement phase transition are the same
in the orientifold daughters and their supersymmetric parent up to 1/N
corrections. We also discuss the Abelian and non-Abelian confining regimes of
four-dimensional QCD-like theories.


title: Spin dependent operators in correlated gaussian bases

abstract:
  In their textbook, Suzuki and Varga [Y. Suzuki and K. Varga, {\em Stochastic
Variational Approach to Quantum-Mechanical Few-Body Problems} (Springer,
Berlin, 1998)] present the stochastic variational method with the correlated
Gaussian basis in a very exhaustive way. The matrix elements for central
potentials are put under a pleasant form but the elements for spin dependent
operators, when treated, are given as very cumbersome expressions. In this
paper, we find a lot of new formulae for those elements. Their expressions are
given in terms of the same geometrical functions that appear in the case of
central potentials. These functions get therefore a universal status; this
property is very useful for numerical applications.


title:
The Standard Model and Supersymmetric Flavor Puzzles at the Large Hadron
  Collider

abstract:
  Can the Large Hadron Collider explain the masses and mixings of the known
fermions? A promising possibility is that these masses and mixings are
determined by flavor symmetries that also govern new particles that will appear
at the LHC. We consider well-motivated examples in supersymmetry with both
gravity- and gauge-mediation. Contrary to spreading belief, new physics need
not be minimally flavor violating. We build non-minimally flavor violating
models that successfully explain all known lepton masses and mixings, but span
a wide range in their predictions for slepton flavor violation. In natural and
favorable cases, these models have metastable sleptons and are characterized by
fully reconstructible events. We outline many flavor measurements that are then
possible and describe their prospects for resolving both the standard model and
new physics flavor puzzles at the Large Hadron Collider.


title:
Mobile $\pi-$kinks and half-integer zero-field-like steps in highly
  discrete alternating $0-\pi$ Josephson junction arrays

abstract:
  The dynamics of a one-dimensional, highly discrete, linear array of
alternating $0-$ and $\pi-$ Josephson junctions is studied numerically, under
constant bias current at zero magnetic field. The calculated current - voltage
characteristics exhibit half-integer and integer zero-field-like steps for even
and odd total number of junctions, respectively. Inspection of the
instantaneous phases reveals that, in the former case, single $\pi-$kink
excitations (discrete semi-fluxons) are supported, whose propagation in the
array gives rise to the $1/2-$step, while in the latter case, a pair of
$\pi-$kink -- $\pi-$antikink appears, whose propagation gives rise to the
$1-$step. When additional $2\pi-$kinks are inserted in the array, they are
subjected to fractionalization, transforming themselves into two closely spaced
$\pi-$kinks. As they propagate in the array along with the single $\pi-$kink or
the $\pi-$kink - $\pi-$antikink pair, they give rise to higher half-integer or
integer zero-field-like steps, respectively.


title:
A Lattice Model for the Fermionic Projector in a Static and Isotropic
  Space-Time

abstract:
  We introduce a lattice model for a static and isotropic system of
relativistic fermions. An action principle is formulated, which describes a
particle-particle interaction of all fermions. The model is designed
specifically for a numerical analysis of the nonlinear interaction, which is
expected to lead to the formation of a Dirac sea structure. We discuss basic
properties of the system. It is proved that the minimum of the variational
principle is attained. First numerical results reveal an effect of spontaneous
symmetry breaking.


title:
Anti-proton and positron Cosmic Rays from Dark Matter annihilation
  around Intermediate Mass Black Holes

abstract:
  Intermediate Mass Black Holes (IMBHs) are candidates to seed the Supermassive
Black Holes (SMBHs), and some could still wander in the Galaxy. In the context
of annihilating dark matter (DM), they are expected to drive huge annihilation
rates, and could therefore significantly enhance the primary cosmic rays (CRs)
expected from annihilation of the DM of the Galactic halo. In this proceeding
(the original paper is Brun et al. 2007), we briefly explain the method to
derive estimates of such exotic contributions to the anti-proton and positron
CR spectra, and the associated statistical uncertainties connected to the
properties of IMBHs. We find boost factors of order $10^4$ to the exotic
fluxes, but associated with very large statistical uncertainties.


title: An Action Principle for the Masses of Dirac Particles

abstract:
  A variational principle is introduced which minimizes an action formulated
for configurations of vacuum Dirac seas. The action is analyzed in position and
momentum space. We relate the corresponding Euler-Lagrange equations to the
notion of state stability. Examples of numerical minimizers are constructed and
discussed.


title:
Asymptotic normality of the Quasi Maximum Likelihood Estimator for
  multidimensional causal processes

abstract:
  Strong consistency and asymptotic normality of the Quasi-Maximum Likelihood
Estimator (QMLE) are given for a general class of multidimensional causal
processes. For particular cases already studied in the literature (for instance
univariate or multivariate GARCH, ARCH, ARMA-GARCH processes) the assumptions
required for establishing these results are often weaker than existing
conditions. The QMLE asymptotic behavior is also given for numerous new
examples of univariate or multivariate processes (for instance TARCH or NLARCH
processes).


title:
Stellar mass estimates in early-type galaxies from lensing+dynamical and
  photometric measurements

abstract:
  In this paper we compare two different diagnostics for estimating stellar
masses in early-type galaxies and we establish their level of reliability. In
particular, we consider the well-studied sample of 15 field elliptical galaxies
selected from the Sloan Lens ACS (SLACS) Survey (z = 0.06-0.33). We examine
here the correlation between the stellar mass values, enclosed inside the
Einstein radius of each lens, based on analyses of lensing and stellar dynamics
combined and based on multiwavelength photometry spectral template fitting. The
lensing+dynamics stellar mass is obtained from the published SLACS Survey
results, assuming a two-component density distribution model and a prior from
the fundamental plane on the mass-to-light ratio for the lens galaxies. The
photometric stellar mass is measured by fitting the observed spectral energy
distribution of the galaxies (from the SDSS multi-band photometry over 354-913
nm) with composite stellar population templates, under the assumption that
light traces stellar mass. The two methods are completely independent. They
rely on several different assumptions, and so, in principle, both can have
significant biases. Based on our sample of massive galaxies, we find
consistency between the lensing+dynamics and the photometric mass estimates. We
obtain a Pearson linear correlation coefficient of 0.94 and a median value of
the ratio between the former and the latter mass measurements of 1.1+/-0.1.
This suggests that both methods can separately yield reliable stellar masses of
early-type galaxies, and confirms that photometric mass estimates are accurate,
as long as optical/near-IR rest frame photometry is available.


title: Determinants of Block Tridiagonal Matrices

abstract:
  An identity is proven that evaluates the determinant of a block tridiagonal
matrix with (or without) corners as the determinant of the associated transfer
matrix (or a submatrix of it).


title: Tunable transmission via quantum state evolution in oval quantum dots

abstract:
  We explore the quantum transmission through open oval shaped quantum dots.
The transmission spectra show periodic resonances and, depending on the
geometry parameter, a strong suppression of the transmission for low energies.
Applying a weak perpendicular magnetic field changes this situation drastically
and introduces a large conductance. We identify the underlying mechanisms being
partially due to the specific shape of the oval that causes a systematic
decoupling of a substantial number of states from the leads. Importantly a
pairwise destructive interference of the transmitting states is encountered
thereby leading to the complete conductance suppression. Coupling properties
and interferences can be tuned via a weak magnetic field. These properties are
robust with respect to the presence of disorder in the quantum dot.


title: Loop Quantization of Polarized Gowdy Model on $T^3$: Classical Theory

abstract:
  The vacuum Gowdy models provide much studied, non-trivial midi-superspace
examples. Various technical issues within Loop Quantum Gravity can be studied
in these models as well as one can hope to understand singularities and their
resolution in the loop quantization. The first step in this program is to
reformulate the model in real connection variables in a manner that is amenable
to loop quantization. We begin with the unpolarized model and carry out a
consistent reduction to the polarized case. Carrying out complete gauge fixing,
the known solutions are recovered.


title: Compact embeddings of model subspaces of the Hardy space

abstract:
  We study embeddings of model (star-invariant) subspaces $K^p_{\Theta}$ of the
Hardy space $H^p$, associated with an inner function $\Theta$. We obtain a
criterion for the compactness of the embedding of $K^p_{\Theta}$ into
$L^p(\mu)$ analogous to the Volberg--Treil theorem on bounded embeddings and
answer a question posed by Cima and Matheson. The proof is based on Bernstein
inequalities for functions in $K^p_{\Theta}$. Also we study measures $\mu$ such
that the embedding operator belongs to a Schatten--von Neumann ideal.


title:
From Discrete Space-Time to Minkowski Space: Basic Mechanisms, Methods
  and Perspectives

abstract:
  This survey article reviews recent results on fermion system in discrete
space-time and corresponding systems in Minkowski space. After a basic
introduction to the discrete setting, we explain a mechanism of spontaneous
symmetry breaking which leads to the emergence of a discrete causal structure.
As methods to study the transition between discrete space-time and Minkowski
space, we describe a lattice model for a static and isotropic space-time,
outline the analysis of regularization tails of vacuum Dirac sea
configurations, and introduce a Lorentz invariant action for the masses of the
Dirac seas. We mention the method of the continuum limit, which allows to
analyze interacting systems. Open problems are discussed.


title:
Violation of Rotational Invariance of Local Realistic Models with Two
  Settings

abstract:
  We have considered a two-particle Bell experiment to visualize the conflict
between rotational invariance of physical laws and a specific local realistic
theory. The experiment is reproducible by using a local realistic theory
obtained in a two-setting Bell experiment. The generalized Bell inequality {[J.
Phys. A: Math. Theor. {\bf 40}, 13101 (2007)]}, which is derived under the
assumption that there exists a rotationally invariant local realistic theory,
turns out to disprove such a local realistic model existing with a two-setting
experiment. This implies that such a model is not rotationally invariant and
should, therefore, be ruled out in some situations.


title:
Loop Quantization of Polarized Gowdy Model on $T^3$: Kinematical States
  and Constraint Operators

abstract:
  In this second paper on loop quantization of Gowdy model, we introduce the
kinematical Hilbert space on which appropriate holonomies and fluxes are well
represented. The quantization of the volume operator and the Gauss constraint
is straightforward. Imposition of the Gauss constraint can be done on the
kinematical Hilbert space to select subspace of gauge invariant states. We
carry out the quantization of the Hamiltonian constraint making specific
choices. Alternative choices are briefly discussed. It appears that to get
spatial correlations reflected in the Hamiltonian constraint, one may have to
adopt the so called `effective operator viewpoint'.


title:
Ergodic Theory, Abelian Groups, and Point Processes Induced by Stable
  Random Fields

abstract:
  We consider a point process sequence induced by a stationary symmetric
alpha-stable (0 < alpha < 2) discrete parameter random field. It is easy to
prove, following the arguments in the one-dimensional case in Resnick and
Samorodnitsky (2004), that if the random field is generated by a dissipative
group action then the point process sequence converges weakly to a cluster
Poisson process. For the conservative case, no general result is known even in
the one-dimensional case. We look at a specific class of stable random fields
generated by conservative actions whose effective dimensions can be computed
using the structure theorem of finitely generated abelian groups. The
corresponding point processes sequence is not tight and hence needs to be
properly normalized in order to ensure weak convergence. This weak limit is
computed using extreme value theory and some counting techniques.


title: Introduction to AdS-CFT

abstract:
  These lectures present an introduction to AdS-CFT, and are intended both for
begining and more advanced graduate students, which are familiar with quantum
field theory and have a working knowledge of their basic methods. Familiarity
with supersymmetry, general relativity and string theory is helpful, but not
necessary, as the course intends to be as self-contained as possible. I will
introduce the needed elements of field and gauge theory, general relativity,
supersymmetry, supergravity, strings and conformal field theory. Then I
describe the basic AdS-CFT scenario, of ${\cal N}=4 $ Super Yang-Mills's
relation to string theory in $AdS_5\times S_5$, and applications that can be
derived from it: 3-point functions, quark-antiquark potential, finite
temperature and scattering processes, the pp wave correspondence and spin
chains. I also describe some general properties of gravity duals of gauge
theories.


title:
XMM-Newton observations of the Galactic globular clusters NGC 2808 and
  NGC 4372

abstract:
  Galactic globular clusters harbour binary systems that are detected as faint
X-ray sources. These close binaries are thought to play an important role in
the stability of the clusters by liberating energy and delaying the inevitable
core collapse of globular clusters. The inventory of close binaries and their
identification is therefore essential. We present XMM-Newton observations of
two Galactic globular clusters: NGC 2808 and NGC 4372. We use X-ray spectral
and variability analysis combined with ultra-violet observations made with the
XMM-Newton optical monitor and published data from the Hubble Space Telescope
to identify sources associated with the clusters. We compare the results of our
observations with estimates from population synthesis models. Five sources out
of 96 are likely to be related to NGC 2808. Nine sources are found in the field
of view of NGC 4372, none being located inside its half-mass radius. We find
one quiescent neutron star low mass X-ray binary candidate in the core of NGC
2808, and propose that the majority of the central sources in NGC 2808 are
cataclysmic variables. An estimation leads to ~20+/-10 cataclysmic variables
with luminosity above 4.25 x 10^31 erg s^-1. Millisecond pulsars could also be
present in the core of NGC 2808, and some sources outside of the half-mass
radius could possibly be linked to the cluster.


title: Iterative Methods for Model Reduction by Domain Decomposition

abstract:
  We propose a method to reduce the computational effort to solve a partial
differential equation on a given domain. The main idea is to split the domain
of interest in two subdomains, and to use different approximation methods in
each of the two subdomains. In particular, in one subdomain we discretize the
governing equations by a canonical scheme, whereas in the other one we solve a
reduced order model of the original problem. Different approaches to couple the
low-order model to the usual discretization are presented. The effectiveness of
these approaches is tested on numerical examples pertinent to non-linear model
problems including the Laplace equation with non-linear boundary conditions and
the compressible Euler equations.


title: Bounds for Behrend's conjecture on the canonical reduction

abstract:
  We prove Behrend's conjecture on the rationality of the canonical reduction
of principal bundles and reductive group schemes for classical groups and give
new bounds for the conjecture for exceptional groups. However we find a
counterexample in the case of G_2-bundles in characteristic 2.


title: Cryptanalysis of an image encryption scheme based on the Hill cipher

abstract:
  This paper studies the security of an image encryption scheme based on the
Hill cipher and reports its following problems: 1) there is a simple necessary
and sufficient condition that makes a number of secret keys invalid; 2) it is
insensitive to the change of the secret key; 3) it is insensitive to the change
of the plain-image; 4) it can be broken with only one known/chosen-plaintext;
5) it has some other minor defects.


title:
Compact embedded hypersurfaces with constant higher order anisotropic
  mean curvatures

abstract:
  Given a positive function $F$ on $S^n$ which satisfies a convexity condition,
for $1\leq r\leq n$, we define the $r$-th anisotropic mean curvature function
$H^F_r$ for hypersurfaces in $\mathbb{R}^{n+1}$ which is a generalization of
the usual $r$-th mean curvature function. We prove that a compact embedded
hypersurface without boundary in $\R^{n+1}$ with $H^F_r={constant}$ is the
Wulff shape, up to translations and homotheties. In case $r=1$, our result is
the anisotropic version of Alexandrov Theorem, which gives an affirmative
answer to an open problem of F. Morgan.


title: Ionization of the hydrogen atom by intense ultrashort laser pulses

abstract:
  The ionization of atomic hydrogen in intense laser fields is studied
theoretically. The calculations were performed applying both quantummechanical
and classical approaches. Treating the problem quantummechanically, the time
dependent Schr\"odinger equation (TDSE) of our system was first transformed
into a pseudo-momentum space and solved in this space iteratively. While
neglecting the Coulomb potential during the solution of the TDSE we got the
results in the Volkov approximation, in the first order solution we taken into
account the Coulomb potential as perturbation. The classical calculations were
performed within the framework of the classical trajectory Monte-Carlo (CTMC)
method.
  The double differential ionization probabilities are calculated for different
laser pulses and a reasonable agreement was found between the theories. Major
differences can be observed in the angular distribution of electrons at low
electron energies between classical and the quantummechanical approaches. At
high electron energies the differences disappear, which indicates that the
generation of low energy electrons is of quantum type, and it is strongly
influenced by the Coulomb potential, while the production of high energy
electrons is of classical type and it is less influenced by the Coulomb
interaction. Our results are also compared with the Coulomb-Volkov (CV) model
calculations.


title:
The T Tauri star RY Tau as a case study of the inner regions of
  circumstellar dust disks

abstract:
  We study the inner region of the circumstellar disk around the TTauri star RY
Tau. Our aim is to find a physical description satisfying the available
interferometric data, obtained with the mid-infrared interferometric instrument
at the Very Large Telescope Interferometer, as well as the spectral energy
distribution. We also compare the findings with the results of similar studies,
including those of intermediate-mass stars. Our analysis is done within the
framework of a passive circumstellar disk, which is optionally supplemented by
the effects of accretion and an added envelope. To achieve a more consistent
and realistic model, we used our continuum transfer code MC3D. In addition, we
studied the shape of the 10um silicate emission feature in terms of the
underlying dust population, both for single-dish and for interferometric
measurements. We show that a modestly flaring disk model with accretion can
explain both the observed spectral energy distribution and the mid-infrared
visibilities obtained with the mid-infrared infrared instrument. We found an
interesting ambiguity: a circumstellar active disk model with an added
envelope, and a lower accretion rate than in the active disk model without
envelope, could represent the observations equally as well. This type of model
with the envelope should be considered a viable alternative in future models of
other TTauri stars. The approach of a disk with a puffed-up inner rim wall and
the influence of a stellar companion is also discussed. From the study of the
silicate emission feature we see evidence for dust evolution in a TTauri star,
with a decreasing fraction of small amorphous and an increasing fraction of
crystalline particles closer to the star.


title:
Investigating Possible Neutrino Decay in Long Baseline Experiment Using
  ICAL as Far end Detector

abstract:
  We investigate the effects of possible decay of neutrinos from a neutrino
factory in a long baseline experiment. We consider the neutrinos from a factory
at CERN and the detector to be the 50 kTon iron calorimeter (ICAL) detector
proposed for India-based Neutrino Observatory (INO). We found considerable
depletion of muon yield at INO for certain value of decay parameters.


title: Isomeric 0- halo-states in 12Be and 11Li

abstract:
  We predict the existence of an isomeric 0$^-$-state in $^{12}$Be at an
excitation energy of about 2.5 MeV, and a 0$^-$-resonance in $^{11}$Li with
both energy and width of about 1 MeV corresponding to two-neutron emission. The
structure of these halo-like states are like the 1$^-$-states which means
essentially a core surrounded by two neutrons in single-particle $s$ and
p-states. The life-time of the $^{12}$Be state is determined by $M1$ or
$M2$-emission, $\tau(M1) \approx 10^{-11}$ s or $\tau(M2) \approx 10^{-8}$ s
estimated for photon energies of 0.1 MeV and 0.6 MeV, respectively.


title:
Fast-neutron induced pre-equilibrium reactions on 55Mn and 63,65Cu at
  energies up to 40 MeV

abstract:
  Excitation functions were measured for the $^{55}$Mn(n,2n)$^{54}$Mn,
$^{55}$Mn(n,$\alpha$)$^{52}$V, $^{63}$Cu(n,$\alpha$)$^{60}$Co,
$^{65}$Cu(n,2n)$^{64}$Cu, and $^{65}$Cu(n,p)$^{65}$Ni reactions from 13.47 to
14.83 MeV. The experimental cross sections are compared with the results of
calculations including all activation channels for the stable isotopes of Mn
and Cu, for neutron incident energies up to 50 MeV. Within the energy range up
to 20 MeV the model calculations are most sensitive to the parameters related
to nuclei in the early stages of the reaction, while the model assumptions are
better established by analysis of the data in the energy range 20-40 MeV. While
the present analysis has taken advantage of both a new set of accurate measured
cross sections around 14 MeV and the larger data basis fortunately available
between 20 and 40 MeV for the Mn and Cu isotopes, the need of additional
measurements below as well as above 40 MeV is pointed out. Keywords: 55Mn,
63,65Cu, E$\leq$40 MeV, Neutron activation cross section measurements, Nuclear
reactions, Model calculations, Manganese, Copper


title: Localizing gravity on Maxwell gauged CP1 model in six dimensions

abstract:
  We shall consider about a 3-brane embedded in six-dimensional space-time with
a negative bulk cosmological constant. The 3-brane is constructed by a
topological soliton solution living in two-dimensional axially symmetric
transverse subspace. Similar to most previous works of six-dimensional soliton
models, our Maxwell gauged CP1 brane model can also achieve to localize gravity
around the 3-brane. The CP1 field is described by a scalar doublet and derived
from O(3) sigma model by projecting it onto two-dimensional complex space. In
that sense, our framework is more effective than other solitonic brane models
concerning with gauge theory. We shall also discuss about linear stability
analysis for our new model by fluctuating all fields.


title: Pulsational models of BL Her stars

abstract:
  We present an updated and homogeneous pulsational scenario for a wide range
of stellar parameters typical of BL Her stars i.e., Population II Cepheids with
periods shorter than 8 days.


title:
Pontrjagin-Thom maps and the homology of the moduli stack of stable
  curves

abstract:
  We study the singular homology (with field coefficients) of the moduli stack
of stable n-pointed complex curves of genus g (the Deligne-Mumford
compactification). Each of its irreducible boundary components determines via
the Pontrjagin-Thom construction a map to a certain infinite loop space whose
homology is well understood. We show that these maps are surjective on homology
in a range of degrees proportional to the genus. This implies the existence of
many new torsion classes in the homology of the moduli stack.


title: Stellar population of the interacting galaxies M51

abstract:
  Stellar photometry of about one million stars in the system of the
interacting galaxies M51 (NGC5194/NGC5195) has been carried out on the basis of
the ACS/WFC images of the Hubble Space telescope. The distance to the system
has been determined by TRGB method and metallicity of red supergiants along the
NGC5194 radius has been measured. A comparison of the spacial distribution of
stars in the main galaxy NGC5194 with our empirical model of spiral galaxies
showed their similarity, in spite of interaction in system M51. It has been
discovered that the "feathers", arising as a result of the interaction of
galaxies, mainly consist of stars of intermediate age.


title: The High-Z hydrogen-like atom: a model for polarized structure functions

abstract:
  The Dirac equation offers a precise analytical description of relativistic
two-particle bound states, when one of the constituent is very heavy and
radiative corrections are neglected. Looking at the high-Z hydrogen-like atom
in the infinite momentum frame and treating the electron as a "parton", various
properties usually attributed to the quark distributions in the nucleon are
tested, in particular: Bj{\o}rken scaling; charge, helicity, transversity and
momentum sum rules; existence of the parton sea; Soffer inequality; correlation
between spin and transverse momentum (Sivers and Boer-Mulders effects);
transverse displacement of the center-of-charge and its connection with the
magnetic moment. Deep inelastic experiments with photon or positron beams at
MeV energies, analogous to DIS or Drell-Yan reactions, are considered.