title:
Supersymmetric Higgs mediated lepton flavor violation at a Photon
  Collider

abstract:
  We study a new signature of lepton flavor violation (LFV) at the Photon
Collider (PC) within Supersymmetric (SUSY) theories. We consider the minimal
supersymmetric standard model within a large $\tan\beta$ scenario with all
superpartner masses in the ${\cal O}$(TeV) while the heavy Higgs bosons masses
lie below the TeV and develop sizable loop induced LFV couplings to the
leptons. We consider a photon collider based on an $e^+e^-$ linear collider
with $\sqrt{s}=800$ GeV with the parameters of the TESLA proposal and show
that, with the expected integrated $\gamma\gamma$-luminosity
$L_{\gamma\gamma}=200\div 500$ fb$^{-1}$, the "$\mu\tau$ fusion" mechanism is
the dominant channel for the process $\gaga\to\mu\tau b\bar{b}$ providing
detailed analytical and numerical studies of the signal and backgrounds. We
impose on the parameter space present direct and indirect constraints from $B$
physics and rare LFV $\tau$-decays and find that the LFV signal can be probed
for masses of the heavy neutral Higgs bosons $A,H$ from 300 GeV up to the
kinematical limit $\simeq 600$ GeV for 30$\leq\tan\beta\leq$60.


title: Direct sampling of optical coherence using quantum interference

abstract:
  We describe a detector that measures the mutual coherence of two optical
fields directly using quantum interference, free from photon noise of the
individual irradiances. Our approach utilizes Raman transition in an atomic
system where the state evolution is driven by the mutual coherence of the
fields interacting with the atoms. Feedback control is used to balance the
interaction of the fields being characterized, providing a measure of the
mutual coherence. We show that the sensitivity of the coherence measurement can
be enhanced significantly above that of conventional interferometric methods
when the mutual coherence of the two fields is weak.


title:
Entanglement of Formation is Non-monotonic with Concurrence-A Simple
  Proof

abstract:
  In this paper we explore the non-monotonic nature of entanglement of
formation with respect to concurrence for pure bipartite states. For pure
bipartite system, one of the basic physical reason of this non-monotonicity
character is due to the existence of incomparable states, i.e., the pure
bipartite states which are not convertible to each other by LOCC with
certainty.


title: Shock fragmentation model for gravitational collapse

abstract:
  A cloud of gas collapsing under gravity will fragment. We present a new
theory for this process, in which layers shocked gas fragment due to their
gravitational instability. Our model explains why angular momentum does not
inhibit the collapse process. The theory predicts that the fragmentation
process produces objects which are significantly smaller than most stars,
implying that accretion onto the fragments plays an essential role in
determining the initial masses of stars. This prediction is also consistent
with the hypothesis that planets can be produced by gravitational collapse.


title:
Ontology Assisted Query Reformulation Using Semantic and Assertion
  Capabilities of OWL-DL Ontologies

abstract:
  End users of recent biomedical information systems are often unaware of the
storage structure and access mechanisms of the underlying data sources and can
require simplified mechanisms for writing domain specific complex queries. This
research aims to assist users and their applications in formulating queries
without requiring complete knowledge of the information structure of underlying
data sources. To achieve this, query reformulation techniques and algorithms
have been developed that can interpret ontology-based search criteria and
associated domain knowledge in order to reformulate a relational query. These
query reformulation algorithms exploit the semantic relationships and assertion
capabilities of OWL-DL based domain ontologies for query reformulation. In this
paper, this approach is applied to the integrated database schema of the EU
funded Health-e-Child (HeC) project with the aim of providing ontology assisted
query reformulation techniques to simplify the global access that is needed to
millions of medical records across the UK and Europe.


title: Orientifolds and D-branes in N=2 gauged linear sigma models

abstract:
  We study parity symmetries and boundary conditions in the framework of gauged
linear sigma models. This allows us to investigate the Kaehler moduli
dependence of the physics of D-branes as well as orientifolds in a Calabi-Yau
compactification. We first determine the parity action on D-branes and define
the set of orientifold-invariant D-branes in the linear sigma model. Using
probe branes on top of orientifold planes, we derive a general formula for the
type (SO vs Sp) of orientifold planes. As applications, we show how
compactifications with and without vector structure arise naturally at
different real slices of the Kaehler moduli space of a Calabi-Yau
compactification. We observe that orientifold planes located at certain
components of the fixed point locus can change type when navigating through the
stringy regime.


title:
Matched asymptotic expansions for twisted elastic knots: a self-contact
  problem with non- trivial contact topology

abstract:
  We derive solutions of the Kirchhoff equations for a knot tied on an
infinitely long elastic rod subjected to combined tension and twist. We
consider the case of simple (trefoil) and double (cinquefoil) knots; other knot
topologies can be investigated similarly. The rod model is based on Hookean
elasticity but is geometrically non-linear. The problem is formulated as a
non-linear self-contact problem with unknown contact regions. It is solved by
means of matched asymptotic expansions in the limit of a loose knot. Without
any a priori assumption, we derive the topology of the contact set, which
consists of an interval of contact flanked by two isolated points of contacts.
We study the influence of the applied twist on the equilibrium.


title:
Mid-Infrared Extinction Mapping of Infrared Dark Clouds: Probing the
  Initial Conditions for Massive Stars and Star Clusters

abstract:
  (Abridged) We use 8 micron Spitzer GLIMPSE images to make extinction maps of
10 IRDCs, selected to be relatively nearby and massive. The extinction mapping
technique requires modeling the IR background intensity behind the cloud, which
is achieved by correcting for foreground emission and then interpolating from
the surrounding regions. The correction for foreground emission can be quite
large, thus restricting the utility of this technique to relatively nearby
clouds. We investigate three methods for the interpolation, finding systematic
differences at about the 10% level, which, for fiducial dust models,
corresponds to a mass surface density Sigma = 0.013 g cm^-2, above which we
conclude this extinction mapping technique attains validity. We examine the
probability distribution function of Sigma in IRDCs. From a qualitative
comparison with numerical simulations of astrophysical turbulence, many clouds
appear to have relatively narrow distributions suggesting relatively low (<5)
Mach numbers and/or dynamically strong magnetic fields. Given cloud kinematic
distances, we derive cloud masses. Rathborne, Jackson & Simon identified cores
within the clouds and measured their masses via mm dust emission. For 43 cores,
we compare these mass estimates with those derived from our extinction mapping,
finding good agreement: typically factors of <~2 difference for individual
cores and an average systematic offset of <~10% for the adopted fiducial
assumptions of each method. We find tentative evidence for a systematic
variation of these mass ratios as a function of core density, which is
consistent with models of ice mantle formation on dust grains and subsequent
grain growth by coagulation, and/or with a temperature decrease in the densest
cores.


title: IceCube: Status and First Results

abstract:
  IceCube is a cubic neutrino telescope under construction at the South Pole
since the austral summer 2004/2005 with a total instrumented volume of the
order of 1 km^3. At the moment it is taking data with 40 deployed strings. The
full detector is expected to be completed in 2011 with up to 80 strings holding
60 digital optical modules (DOMs) each. The progenitor detector AMANDA has been
operating at the same site since 1997 and is still functioning as a means to
enhance neutrino effective area at energies below 100 GeV. A summary of science
results and status of the project is presented.


title: Dirac operators for coadjoint orbits of compact Lie groups

abstract:
  The coadjoint orbits of compact Lie groups carry many K\"ahler structures,
which include a Riemannian metric and a complex structure. We provide a fairly
explicit formula for the Levi-Civita connection of the Riemannian metric, and
we use the complex structure to give a fairly explicit construction of a
canonical Dirac operator for the Riemannian metric, in a way that avoids use of
the Spin^c groups. Substantial parts of our results apply to compact
almost-Hermitian homogeneous spaces, and to other connections besides the
Levi-Civita connection. For these other connections we give a criterion that is
both necessary and sufficient for their Dirac operator to be formally
self-adjoint.
  We hope to use the detailed results given here to clarify statements in the
literature of high-eneregy physics concerning "Dirac operators" for matrix
algebras that converge to coadjoint orbits. To facilitate this we employ here
only global methods -- we never use local coordinate charts, and we use the
cross-section modules of vector bundles.


title: Field sensitivity to L^p variations of a scatterer

abstract:
  For the problem of diffraction of harmonic scalar waves by a lossless
periodic slab scatterer, we analyze field sensitivity with respect to the
material coefficients of the slab. The governing equation is the Helmholtz
equation, which describes acoustic or electromagnetic fields. The main theorem
establishes the variational Frechet derivative of the scattered field measured
in the H^1 (root-mean-square-gradient) norm as a function of the material
coefficients measured in an L^p (p-power integral) norm, with 2<p<infinity, as
long as these coefficients are bounded above and below by positive constants
and do not admit resonance. The derivative is Lipschitz continuous. We also
establish the variational derivative of the transmitted energy with respect to
the material coefficients in L^p.


title: Issues of Reggeization in $qq'$ Back-Angle Scattering

abstract:
  The Kirschner-Lipatov result for the DLLA of high-energy $qq'$ backward
scattering is re-derived without the use of integral equations. It is shown
that part of the inequalities between the variables in the
logarithmically-divergent integrals is inconsequential. The light-cone
wave-function interpretation under the conditions of backward scattering is
discussed. It is argued that for hadron-hadron scattering in the valence-quark
model the reggeization should manifest itself at full strength starting from
$s_{hh}=50 GeV^2$.


title: The hydrodynamics of swimming microorganisms

abstract:
  Cell motility in viscous fluids is ubiquitous and affects many biological
processes, including reproduction, infection, and the marine life ecosystem.
Here we review the biophysical and mechanical principles of locomotion at the
small scales relevant to cell swimming (tens of microns and below). The focus
is on the fundamental flow physics phenomena occurring in this inertia-less
realm, and the emphasis is on the simple physical picture. We review the basic
properties of flows at low Reynolds number, paying special attention to aspects
most relevant for swimming, such as resistance matrices for solid bodies, flow
singularities, and kinematic requirements for net translation. Then we review
classical theoretical work on cell motility: early calculations of the speed of
a swimmer with prescribed stroke, and the application of resistive-force theory
and slender-body theory to flagellar locomotion. After reviewing the physical
means by which flagella are actuated, we outline areas of active research,
including hydrodynamic interactions, biological locomotion in complex fluids,
the design of small-scale artificial swimmers, and the optimization of
locomotion strategies.


title: Super-sequences in the arc component of a compact connected group

abstract:
  Let G be an abelian topological group. The symbol \hat{G} denotes the group
of all continuous characters \chi : G --> T endowed with the compact open
topology. A subset E of G is said to be qc-dense in G provided that \chi(E)
\subseteq \phi([-1/4,1/4]) holds only for the trivial character \chi \in
\hat{G}, where \phi : R --> T = R/Z is the canonical homomorphism. A
super-sequence is a non-empty compact Hausdorff space S with at most one
non-isolated point (to which S converges). We prove that an infinite compact
abelian group G is connected if and only if its arc component G_a contains a
super-sequence converging to 0 that is qc-dense in G. This gives as a corollary
a recent theorem of Aussenhofer: For a connected locally compact abelian group
G, the restriction homomorphism r : \hat{G} --> \hat{G}_a defined by r(\chi) =
\chi\restriction_{G_a} for \chi \in \hat{G}, is a topological isomorphism. We
also show that an infinite compact group G is connected if and only if its arc
component G_a contains a super-sequence S converging to the identity e that
generates a dense subgroup of G (equivalently, S \setminus {e} is an infinite
suitable set for G in the sense of Hofmann and Morris).


title: On superembedding approach to type IIB 7-branes

abstract:
  In search for a dynamical description of Q7-branes, which were known as
solutions of supergravity equations and then conjectured to be dynamical
objects of type IIB string theory, we study the superembedding description of
7-branes in curved type IIB supergravity superspace. With quite minimal and
natural assumptions we have found that there is no place for Q7-branes as
dynamical branes in superembedding approach. Our study might give implications
for the old-standing problem of the covariant and supersymmetric description of
multiple Dp-brane systems.


title:
Modeling of Disk-Star Interaction: Different Regimes of Accretion and
  Variability

abstract:
  The appearance and time variability of accreting millisecond X-ray pulsars
(hereafter AMXPs, e.g. Wijnands & van der Klis 1998) depends strongly on the
accretion rate, the effective viscosity and the effective magnetic diffusivity
of the disk-magnetosphere boundary. The accretion rate is the main parameter
which determines the location of the magnetospheric radius of the star for a
given stellar magnetic field. We introduce a classification of accreting
neutron stars as a function of the accretion rate and show the corresponding
stages obtained from our global 3D magnetohydrodynamic (MHD) simulations and
from our axisymmetric MHD simulations. We discuss the expected variability
features in each stage of accretion, both periodic and quasi-periodic (QPOs).
We conclude that the periodicity may be suppressed at both very high and very
low accretion rates. In addition the periodicity may disappear when ordered
funnel flow accretion is replaced by disordered accretion through the
interchange instability.


title: On the Value of a Social Network

abstract:
  In this paper we investigate the value of a social network with respect to
the probability mechanism underlying its structure. Specifically, we compute
the value for small world and scale free networks. We provide evidence in
support of the value to be given by Zipfs law.


title:
Sparse Component Analysis (SCA) in Random-valued and Salt and Pepper
  Noise Removal

abstract:
  In this paper, we propose a new method for impulse noise removal from images.
It uses the sparsity of images in the Discrete Cosine Transform (DCT) domain.
The zeros in this domain give us the exact mathematical equation to reconstruct
the pixels that are corrupted by random-value impulse noises. The proposed
method can also detect and correct the corrupted pixels. Moreover, in a simpler
case that salt and pepper noise is the brightest and darkest pixels in the
image, we propose a simpler version of our method. In addition to the proposed
method, we suggest a combination of the traditional median filter method with
our method to yield better results when the percentage of the corrupted samples
is high.


title:
The Red Rectangle: Its Shaping Mechanism and its Source of Ultraviolet
  Photons

abstract:
  The proto-planetary Red Rectangle nebula is powered by HD 44179, a
spectroscopic binary (P = 318 d), in which a luminous post-AGB component is the
primary source of both luminosity and current mass loss. Here, we present the
results of a seven-year, eight-orbit spectroscopic monitoring program of HD
44179, designed to uncover new information about the source of the
Lyman/far-ultraviolet continuum in the system as well as the driving mechanism
for the bipolar outflow producing the current nebula. Our observations of the
H-alpha line profile around the orbital phase of superior conjunction reveal
the secondary component to be the origin of the fast (max. v~560$ km s$^{-1}$)
bipolar outflow in the Red Rectangle. The variation of total H-alpha flux from
the central H II region with orbital phase also identifies the secondary or its
surroundings as the source of the far-ultraviolet ionizing radiation in the
system. The estimated mass of the secondary (~0.94 M$\sun$) and the speed of
the outflow suggest that this component is a main sequence star and not a white
dwarf, as previously suggested. We identify the source of the
Lyman/far-ultraviolet continuum in the system as the hot, inner region
(T$_{max} \ge 17,000$ K) of an accretion disk surrounding the secondary, fed by
Roche lobe overflow from the post-AGB primary at a rate of about $2 -
5\times10^{-5}$ M$\sun$ yr$^{-1}$. The total luminosity of the accretion disk
around the secondary is estimated to be at least 300 L$\sun$, about 5% of the
luminosity of the entire system. (abridged)


title:
Magnetic and Metallic State at Intermediate Hubbard U Coupling in
  Multiorbital Models for Undoped Fe Pnictides

abstract:
  Multi-orbital Hubbard model Hamiltonians for the undoped parent compounds of
the Fe-pnictide superconductors are here investigated using mean-field
techniques. For a realistic four-orbital model, our results show the existence
of an intermediate Hubbard U coupling regime where the mean-field ground state
has spin stripe magnetic order, as in neutron scattering experiments, while
remaining metallic, due to the phenomenon of band overlaps. The angle-resolved
photoemission intensity and Fermi surface of this magnetic and metallic state
are discussed. Other models are also investigated, including a two orbital
model where not only the mean-field technique can be used, but also Exact
Diagonalization in small clusters and the Variational Cluster Approximation in
the bulk. The combined results of the three techniques point toward the
existence of an intermediate-coupling magnetic and metallic state in the
two-orbital model, similar to the intermediate coupling mean-field state of the
four-orbital model. We conclude that the state discussed here is compatible
with the experimentally known properties of the undoped Fe-pnictides.


title: Dressed Polyakov loops and center symmetry from Dirac spectra

abstract:
  We construct a novel observable for finite temperature QCD that relates
confinement and chiral symmetry. It uses phases as boundary conditions for the
fermions. We discuss numerical and analytical aspects of this observable, like
its spectral behavior below and above the critical temperature, as well as the
connection to chiral condensate and center symmetry.


title: Confinement and Green functions in Landau-gauge QCD

abstract:
  In a functional approach to QCD the infrared behaviour of Landau gauge Green
functions is investigated. Positivity violation for, and thus confinement of,
gluons is demonstrated, and the analytic structure of the gluon propagator is
studied. Quark confinement is related to an infrared divergence of the
quark-gluon vertex. In the latter various components are dynamically induced
due to the spontaneous breaking of chiral symmetry. As a result an infrared
finite running coupling in the Yang-Mills sector is derived whereas the running
coupling related to the quark-gluon vertex is infrared divergent. Based on a
truncation for the quark-gluon vertex Dyson-Schwinger equation, which respects
the analytically determined infrared behavior, numerical results for the
coupled system of the quark propagator and vertex Dyson-Schwinger equations are
presented. The resulting quark mass function as well as the vertex function
show only a very weak dependence on the current quark mass in the deep
infrared. From this we infer by an analysis of the quark-quark scattering
kernel a linearly rising quark potential with an almost mass independent string
tension in the case of broken chiral symmetry.


title:
Deep inelastic and dipole scattering on finite length hot
  $\mathcal{N}=4$ SYM matter

abstract:
  Deep inelastic scattering of $\mathcal{R}$-currents and the scattering of a
small dipole on finite length hot $\mathcal{N}=4$ SYM matter are discussed. In
each case we find the scale when scattering becomes strong is determined by a
saturation momentum $Q^2_s \sim LT^3/x$ where $L$ is the length of the matter.
For $\mathcal{R}$-currents we analyze the operator product expansion. For
infinite length matter the series generated by the OPE is not Borel summable
but we are able to determine the exponential part of the tunneling amplitude
determining $F_2$ when $\frac{Q^2}{Q^2_s}\gg 1$ from the position of the
singularity closest to the origin on the real axis of the Borel plane. In
finite length matter the OPE series is not convergent but it is Borel summable.
When a small dipole, and the string connecting the ends of the dipole, pass
through hot matter there is an induced motion of the string in the $5^{th}$
dimension. When $T^4 L \cosh \eta$, with the $\eta$ the rapidity of the string,
is large enough the string would normally break into several parts after
leaving the medium, however, this cannot happen in the classical approximation
in which we work.


title: Thermal ground state for pure SU(2) Yang-Mills thermodynamics

abstract:
  In this proceeding the emergence of a composite, adjoint-scalar field as an
average over (trivial holonomy) calorons and anti-calorons is reviewed. This
composite field acts as a background field to the dynamics of perturbative
gluons, to which is coupled via an effective, gauge invariant Lagrangian valid
for temperatures above the deconfinement phase transition. Moreover, also an
Higgs mechanism is induced by the composite field: two gluons acquire a
quasi-particle thermal mass. On the phenomenological side the composite field
acts as a bag pressure which shows a linear dependence on the temperature. As a
result the linear rise with temperature of the trace anomaly is obtained and is
compared to recent lattice studies.


title: Parametric Bing and Krasinkiewicz maps: revisited

abstract:
  Let $M$ be a complete metric $ANR$-space such that for any metric compactum
$K$ the function space $C(K,M)$ contains a dense set of Bing (resp.,
Krasinkiewicz) maps. It is shown that $M$ has the following property: If
$f\colon X\to Y$ is a perfect surjection between metric spaces, then $C(X,M)$
with the source limitation topology contains a dense $G_\delta$-subset of maps
$g$ such that all restrictions $g|f^{-1}(y)$, $y\in Y$, are Bing (resp.,
Krasinkiewicz) maps. We apply the above result to establish some mapping
theorems for extensional dimension.


title: Can free strings propagate across plane wave singularities?

abstract:
  We study free string propagation in families of plane wave geometries
developing strong scale-invariant singularities in certain limits. We relate
the singular limit of the evolution for all excited string modes to that of the
center-of-mass motion (the latter existing for discrete values of the overall
plane wave profile normalization). Requiring that the entire excitation energy
of the string should be finite turns out to be quite restrictive and
essentially excludes consistent propagation across the singularity, unless
dimensionful scales are introduced at the singular locus (in an otherwise
scale-invariant space-time).


title: Anti-de Sitter space from supersymmetric gauge theory

abstract:
  We construct a four dimensional Yang-Mills theory with ${\cal N}=4$ twisted
supersymmetry whose classical vacua correspond to four dimensional anti-de
Sitter space. The theory utilizes a complex gauge field whose real part is a
spin connection which is used to enforce local Lorentz invariance. The
imaginary part of the connection can then be interpreted as a vierbein. The
topological construction ensures that the partition function and classical
vacua are independent of the background geometry. Additionally a supersymmetric
and gauge invariant lattice construction is possible yielding a
non-perturbative definition of the theory.


title: SuperIso program and flavor data constraints

abstract:
  We present here an overview of the SuperIso program which is a public code
dedicated to the calculation of flavor physics observables in supersymmetry.
The main purpose of the SuperIso program is to provide, by confronting the
theoretical predictions to the experimental data for flavor observables,
indirect constraints on the parameters of supersymmetry. These constraints can
then provide limits on physical masses of yet undiscovered new particles, such
as charged Higgs bosons.


title:
Theory of finite-entanglement scaling at one-dimensional quantum
  critical points

abstract:
  Studies of entanglement in many-particle systems suggest that most quantum
critical ground states have infinitely more entanglement than non-critical
states. Standard algorithms for one-dimensional many-particle systems construct
model states with limited entanglement, which are a worse approximation to
quantum critical states than to others. We give a quantitative theory of
previously observed scaling behavior resulting from finite entanglement at
quantum criticality: the scaling theory of finite entanglement is only
superficially similar to finite-size scaling, and has a different physical
origin. We find that finite-entanglement scaling is governed not by the scaling
dimension of an operator but by the "central charge" of the critical point,
which counts its universal degrees of freedom. An important ingredient is the
recently obtained universal distribution of density-matrix eigenvalues at a
critical point\cite{calabrese1}. The parameter-free theory is checked against
numerical scaling at several quantum critical points.


title: A refined model for spinning dust radiation

abstract:
  We present a comprehensive treatment of the spectrum of electric dipole
emission from spinning dust grains, updating the commonly used model of Draine
and Lazarian. Grain angular velocity distributions are computed using the
Fokker-Planck equation; we revisit the drift and diffusion coefficients for the
major torques on the grain, including collisions, grain-plasma interactions,
and infrared emission. We use updated grain optical properties and size
distributions. The theoretical formalism is implemented in the companion code,
SPDUST, which is publicly available. The effect of some environmental and grain
parameters on the emissivity is shown and analysed.


title: Reconstructing Baryon Oscillations: A Lagrangian Theory Perspective

abstract:
  Recently Eisenstein and collaborators introduced a method to `reconstruct'
the linear power spectrum from a non-linearly evolved galaxy distribution in
order to improve precision in measurements of baryon acoustic oscillations. We
reformulate this method within the Lagrangian picture of structure formation,
to better understand what such a method does, and what the resulting power
spectra are. We show that reconstruction does not reproduce the linear density
field, at second order. We however show that it does reduce the damping of the
oscillations due to non-linear structure formation, explaining the improvements
seen in simulations. Our results suggest that the reconstructed power spectrum
is potentially better modeled as the sum of three different power spectra, each
dominating over different wavelength ranges and with different non-linear
damping terms. Finally, we also show that reconstruction reduces the
mode-coupling term in the power spectrum, explaining why mis-calibrations of
the acoustic scale are reduced when one considers the reconstructed power
spectrum.


title: One Dimensional Dynamical Models of the Carina Nebula Bubble

abstract:
  We have tested the two main theoretical models of bubbles around massive star
clusters, Castor et al. and Chevalier & Clegg, against observations of the well
studied Carina Nebula. The Castor et al. theory over-predicts the X-ray
luminosity in the Carina bubble by a factor of 60 and expands too rapidly, by a
factor of 4; if the correct radius and age are used, the predicted X-ray
luminosity is even larger. In contrast, the Chevalier & Clegg model
under-predicts the X-ray luminosity by a factor of 10. We modify the Castor et
al. theory to take into account lower stellar wind mass loss rates, radiation
pressure, gravity, and escape of or energy loss from the hot shocked gas. We
argue that energy is advected rather than radiated from the bubble. We
undertake a parameter study for reduced stellar mass loss rates and for various
leakage rates and are able to find viable models. The X-ray surface brightness
in Carina is highest close to the bubble wall, which is consistent with
conductive evaporation from cold clouds. The picture that emerges is one in
which the hot gas pressure is far below that found by dividing the
time-integrated wind luminosity by the bubble volume; rather, the pressure in
the hot gas is set by pressure equilibrium with the photoionized gas at T=10^4
K. It follows that the shocked stellar winds are not dynamically important in
forming the bubbles.


title: Collective modes and emergent SO(6) symmetry in the iron pnictides

abstract:
  We show the existence of an emergent SO(6) symmetry in the low energy
description of the iron pnictides. This approximate symmetry provides a
unifying framework for the occurrence of spin density wave (SDW) and
superconductivity (SC) in these materials. We use this symmetry to make several
predictions for future experiments, including the topology of the phase diagram
and the presence of various resonant modes in neutron scattering experiments in
both the SC and SDW phases. We also predict the existence of a new "Orbital
Density Wave" state, which competes with both SDW and SC orders.


title:
Ground-based calibration and characterization of the Fermi Gamma-Ray
  Burst Monitor Detectors

abstract:
  One of the scientific objectives of NASA's Fermi Gamma-ray Space Telescope is
the study of Gamma-Ray Bursts (GRBs). The Fermi Gamma-Ray Burst Monitor (GBM)
was designed to detect and localize bursts for the Fermi mission. By means of
an array of 12 NaI(Tl) (8 keV to 1 MeV) and two BGO (0.2 to 40 MeV)
scintillation detectors, GBM extends the energy range (20 MeV to > 300 GeV) of
Fermi's main instrument, the Large Area Telescope, into the traditional range
of current GRB databases. The physical detector response of the GBM instrument
to GRBs is determined with the help of Monte Carlo simulations, which are
supported and verified by on-ground individual detector calibration
measurements. We present the principal instrument properties, which have been
determined as a function of energy and angle, including the channel-energy
relation, the energy resolution, the effective area and the spatial
homogeneity.


title:
Real-time gauge/gravity duality: Prescription, Renormalization and
  Examples

abstract:
  We present a comprehensive analysis of the prescription we recently put
forward for the computation of real-time correlation functions using
gauge/gravity duality. The prescription is valid for any holographic
supergravity background and it naturally maps initial and final data in the
bulk to initial and final states or density matrices in the field theory. We
show in detail how the technique of holographic renormalization can be applied
in this setting and we provide numerous illustrative examples, including the
computation of time-ordered, Wightman and retarded 2-point functions in
Poincare and global coordinates, thermal correlators and higher-point
functions.


title: Dynamical mixing of two stellar populations in globular clusters

abstract:
  Stars in globular clusters (GCs) exhibit a peculiar chemical pattern with
strong abundance variations in light elements along with a constant abundance
in heavy elements. These abundance anomalies can be explained by a primordial
pollution due to a first generation of fast rotating massive stars which
released slow winds into the ISM from which a second generation of chemically
anomalous stars can be formed. In particular the observed ratio of anomalous
and standard stars in clusters can be used to constrain the dynamical evolution
of GCs as around 95% of the standard stars need to be lost by the clusters. We
show that both residual gas expulsion during the cluster formation and long
term evolution are needed to achieve this ratio.


title:
Metal enrichment of the neutral gas of blue compact dwarf galaxies: the
  compelling case of Pox 36

abstract:
  We present the analysis of the interstellar spectrum of Pox 36 with the Far
Ultraviolet Spectroscopic Explorer (FUSE). Pox 36 was selected because of the
relatively low foreground gas content that makes it possible to detect
absorption-lines weak enough that unseen components should not be saturated.
Interstellar lines of HI, NI, OI, SiII, PII, ArI, and FeII are detected. Column
densities are derived directly from the observed line profiles except for HI,
whose lines are contaminated by stellar absorption. We used the TLUSTY models
to remove the stellar continuum and isolate the interstellar component. The
best fit indicates that the dominant stellar population is B0. The fit of the
interstellar HI line gives a column density of 10^{20.3\pm0.4} cm-2. Chemical
abundances were then computed from the column densities using the dominant
ionization stage in the neutral gas. Our abundances are compared to those
measured from emission-line spectra in the optical. Our results suggest that
the neutral gas of Pox 36 is metal-deficient by a factor ~7 as compared to the
ionized gas, and they agree with a metallicity of ~1/35 Z$_\odot$. Conclusions:
The abundance discontinuity between the neutral and ionized phases implies that
most of the metals released by consecutive star-formation episodes mixes with
the HI gas. The volume extent of the enrichment is so large that the
metallicity of the neutral gas increases only slightly. The star-forming
regions could be enriched only by a small fraction (~1%), but it would greatly
enhance its metallicity. Our results are compared to those of other BCDs. We
confirm the overall underabundance of metals in their neutral gas, with perhaps
only the lowest metallicity BCDs showing no discontinuity.


title: The ages of Galactic globular clusters in the context of self-enrichment

abstract:
  A significant fraction of stars in globular clusters (about 70%-85%) exhibit
peculiar chemical patterns with strong abundance variations in light elements
along with constant abundances in heavy elements. These abundance anomalies can
be created in the H-burning core of a first generation of fast rotating massive
stars and the corresponding elements are convoyed to the stellar surface thanks
to rotational induced mixing. If the rotation of the stars is fast enough this
matter is ejected at low velocity through a mechanical wind at the equator. It
then pollutes the ISM from which a second generation of chemically anomalous
stars can be formed. The proportion of anomalous to normal star observed today
depends on at least two quantities : (1) the number of polluter stars; (2) the
dynamical history of the cluster which may lose during its lifetime first and
second generation stars in different proportions. Here we estimate these
proportions based on dynamical models for globular clusters. When internal
dynamical evolution and dissolution due to tidal forces are accounted for,
starting from an initial fraction of anomalous stars of 10% produces a present
day fraction of about 25%, still too small with respect to the observed 70-85%.
In case gas expulsion by supernovae is accounted for, much higher fraction is
expected to be produced. In this paper we also address the question of the
evolution of the second generation stars that are He-rich, and deduce
consequences for the age determination of globular clusters.


title:
Photo-heating and supernova feedback amplify each other's effect on the
  cosmic star formation rate

abstract:
  Photo-heating associated with reionisation and kinetic feedback from
core-collapse supernovae have previously been shown to suppress the
high-redshift cosmic star formation rate. Here we investigate the interplay
between photo-heating and supernova feedback using a set of cosmological,
smoothed particle hydrodynamics simulations. We show that photo-heating and
supernova feedback mutually amplify each other's ability to suppress the star
formation rate. Our results demonstrate the importance of the simultaneous,
non-independent inclusion of these two processes in models of galaxy formation
to estimate the strength of the total negative feedback they exert. They may
therefore be of particular relevance to semi-analytic models in which the
effects of photo-heating and supernova feedback are implicitly assumed to act
independently of each other.


title:
Polarization dependence of semiconductor exciton and biexciton
  contributions to phase-resolved optical two-dimensional Fourier-transform
  spectra

abstract:
  We study the coherent light-matter interactions of GaAs quantum wells
associated with excitons, biexcitons and many-body effects. For most
polarization configurations, excitonic features dominate the phase-resolved
two-dimensional Fourier-transform (2DFT) spectra and have dispersive
lineshapes, indicating the presence of many-body interactions. For cross-linear
excitation, excitonic features become weak and absorptive due to the strong
suppression of many-body effects; a result that can not be directly determined
in transient four-wave mixing experiments. The biexcitonic features do not
weaken for cross-polarized excitation and thus are more important.


title:
A Characteristic Division Between the Fueling of Quasars and Seyferts:
  Five Simple Tests

abstract:
  Given the existence of the M_BH-sigma relation, models of self-regulated
black hole (BH) growth require both a fuel supply and growth of the host bulge
to deepen the potential, or else the system will either starve or self-regulate
without sustained activity. This suggests that bright quasars must be triggered
in major mergers: a large fraction of the galaxy must be converted to new bulge
mass in a dynamical time or less. Low-luminosity AGN, in contrast, require
little bulge growth and small gas supplies, and could be triggered in more
common non-merger events. This predicts a transition to merger-induced fueling
around the traditional quasar-Seyfert luminosity divide (growth of BH masses
above/below 10^7 M_sun). We compile observations to test several predictions of
such a division, including: (1) A transition to bulge-dominated hosts. (2) A
transition between 'pseudobulges' and 'classical' bulges hosting the remnant
BHs: pseudobulges are formed in secular processes and minor mergers, whereas
classical bulges are relics of major mergers. (3) An increase in the amplitude
of small-scale clustering where mergers are more efficient. (4) Different
redshift evolution, with gas-rich merger rates rising to redshifts z>2 while
secular processes are relatively constant in time. (5) An increasing prominence
of post-starburst features in more luminous systems. Our compilation of
observations provides tentative evidence for the predicted division around the
Seyfert-quasar threshold. We discuss how future observations can improve these
constraints and break degeneracies between different fueling models.


title: A note on low energy scattering for homogeneous long range potentials

abstract:
  We explicitly calculate the scattering matrix at energy zero for attractive,
radial and homogeneous long-range potentials. This proves a conjecture by
Derezinski and Skibsted.


title: Gravity Waves from Tachyonic Preheating after Hybrid Inflation

abstract:
  We study the stochastic background of gravitational waves produced from
preheating in hybrid inflation models. We investigate different dynamical
regimes of preheating in these models and we compute the resulting gravity wave
spectra using analytical estimates and numerical simulations. We discuss the
dependence of the gravity wave frequencies and amplitudes on the various
potential parameters. We find that large regions of the parameter space leads
to gravity waves that may be observable in upcoming interferometric
experiments, including Advanced LIGO, but this generally requires very small
coupling constants.


title: Extremal Black Hole/CFT Correspondence in (Gauged) Supergravities

abstract:
  We extend the investigation of the recently proposed Kerr/CFT correspondence
to large classes of rotating black hole solutions in gauged and ungauged
supergravities. The correspondence, proposed originally for four-dimensional
Kerr black holes, asserts that the quantum states in the near-horizon region of
an extremal rotating black hole are holographically dual to a two-dimensional
chiral theory whose Virasoro algebra arises as an asymptotic symmetry of the
near-horizon geometry. In fact in dimension D there are [(D-1)/2] commuting
Virasoro algebras. We consider a general canonical class of near-horizon
geometries in arbitrary dimension D, and show that in any such metric, the
[(D-1)/2] central charges each imply, via the Cardy formula, a microscopic
entropy that agrees with the Bekenstein-Hawking entropy of the associated
extremal black hole. In the remainder of the paper we show for most of the
known rotating black hole solutions of gauged supergravity, and for the
ungauged supergravity solutions with four charges in D=4 and three charges in
D=5, that their extremal near-horizon geometries indeed lie within the
canonical form. This establishes that in all these examples, the microscopic
entropies of the dual CFTs agree with the Bekenstein-Hawking entropies of the
extremal rotating black holes.


title: About density functional theory interpretation

abstract:
  Two forms of relativistic density functional are derived from Dirac equation.
Based on their structure analysis model of split electron is proposed. In this
model electric charge and mass of electron behave like two point-like
particles. It is shown that two electrons obeying this model cannot occupy the
same quantum state. Empirical verification of the model is discussed.


title:
Microscopic origin of pressure-induced phase transitions in
  iron-pnictide $AFe_2As_2$ superconductors: an {ab initio} molecular-dynamics
  study

abstract:
  Using {\it ab initio} molecular dynamics we investigate the electronic and
lattice structure of $A$Fe$_2$As$_2$ ($A$=Ca, Sr, Ba) under pressure. We find
that the structural phase transition (orthorhombic to tetragonal symmetry) is
always accompanied by a magnetic phase transition in all the compounds, while
the nature of the transitions is different for the three systems. Our
calculations explain the origin of the existence of a collapsed tetragonal
phase in CaFe$_2$As$_2$ and its absence in BaFe$_2$As$_2$. We argue that
changes of the Fermi surface nesting features dominate the phase transition
under pressure rather than spin frustration or a Kondo scenario. The
consequences for superconductivity are discussed.


title:
On the non-quadraticity of values of the q-exponential function and
  related q-series

abstract:
  We investigate arithmetic properties of values of the entire function $$
F(z)=F_q(z;\lambda)=\sum_{n=0}^\infty\frac{z^n}{\prod_{j=1}^n(q^j-\lambda)},
\qquad |q|>1, \quad \lambda\notin q^{\mathbb Z_{>0}}, $$ that includes as
special cases the Tschakaloff function ($\lambda=0$) and the $q$-exponential
function ($\lambda=1$). In particular, we prove the non-quadraticity of the
numbers $F_q(\alpha;\lambda)$ for integral $q$, rational $\lambda$ and
$\alpha\notin-\lambda q^{\mathbb Z_{>0}}$, $\alpha\ne0$.


title:
Environmental Effects in Clusters: Modified Far-Infrared--Radio
  Relations within Virgo Cluster Galaxies

abstract:
  (abridged) We present a study on the effects of the intracluster medium (ICM)
on the interstellar medium (ISM) of 10 Virgo cluster spiral galaxies using {\it
Spitzer} far-infrared (FIR) and VLA radio continuum imaging. Relying on the
FIR-radio correlation within normal galaxies, we use our infrared data to
create model radio maps which we compare to the observed radio images. For 6 of
our sample galaxies we find regions along their outer edges that are highly
deficient in the radio compared with our models. We believe these observations
are the signatures of ICM ram pressure. For NGC 4522 we find the radio deficit
region to lie just exterior to a region of high radio polarization and flat
radio spectral index, although the total 20 cm radio continuum in this region
does not appear strongly enhanced. These characteristics seem consistent for
other galaxies with radio polarization data in the literature. The strength of
the radio deficit is inversely correlated with the time since peak pressure as
inferred from stellar population studies and gas stripping simulations,
suggesting the strength of the radio deficit is good indicator of the strength
of the current ram pressure. We also find that galaxies having {\it local}
radio {\it deficits} appear to have {\it enhanced global} radio fluxes. Our
preferred physical picture is that the observed radio deficit regions arise
from the ICM wind sweeping away cosmic-ray (CR) electrons and the associated
magnetic field, thereby creating synchrotron tails as observed for some of our
galaxies. We propose that CR particles are also re-accelerated by ICM-driven
shocklets behind the observed radio deficit regions which in turn enhances the
remaining radio disk brightness.


title:
Impact ionization rates for Si, GaAs, InAs, ZnS, and GaN in the $GW$
  approximation

abstract:
  We present first-principles calculations of the impact ionization rate (IIR)
in the $GW$ approximation ($GW$A) for semiconductors. The IIR is calculated
from the quasiparticle (QP) width in the $GW$A, since it can be identified as
the decay rate of a QP into lower energy QP plus an independent electron-hole
pair. The quasiparticle self-consistent $GW$ method was used to generate the
noninteracting hamiltonian the $GW$A requires as input. Small empirical
corrections were added so as to reproduce experimental band gaps. Our results
are in reasonable agreement with previous work, though we observe some
discrepancy. In particular we find high IIR at low energy in the narrow gap
semiconductor InAs.


title: Generic theory of colloidal transport

abstract:
  We discuss the motion of colloidal particles relative to a two component
fluid consisting of solvent and solute. Particle motion can result from (i) net
body forces on the particle due to external fields such as gravity; (ii) slip
velocities on the particle surface due to surface dissipative phenomena. The
perturbations of the hydrodynamic flow field exhibits characteristic
differences in cases (i) and (ii) which reflect different patterns of momentum
flux corresponding to the existence of net forces, force dipoles or force
quadrupoles. In the absence of external fields, gradients of concentration or
pressure do not generate net forces on a colloidal particle. Such gradients can
nevertheless induce relative motion between particle and fluid. We present a
generic description of surface dissipative phenomena based on the linear
response of surface fluxes driven by conjugate surface forces. In this
framework we discuss different transport scenarios including self-propulsion
via surface slip that is induced by active processes on the particle surface.
We clarify the nature of force balances in such situations.


title:
Critical exponents for the homology of Fortuin-Kasteleyn clusters on a
  torus

abstract:
  A Fortuin-Kasteleyn cluster on a torus is said to be of type $\{a,b\},
a,b\in\mathbb Z$, if it possible to draw a curve belonging to the cluster that
winds $a$ times around the first cycle of the torus as it winds $-b$ times
around the second. Even though the $Q$-Potts models make sense only for $Q$
integers, they can be included into a family of models parametrized by
$\beta=\sqrt{Q}$ for which the Fortuin-Kasteleyn clusters can be defined for
any real $\beta\in (0,2]$. For this family, we study the probability
$\pi({\{a,b\}})$ of a given type of clusters as a function of the torus modular
parameter $\tau=\tau_r+i\tau_i$. We compute the asymptotic behavior of some of
these probabilities as the torus becomes infinitely thin. For example, the
behavior of $\pi(\{1,0\})$ is studied along the line $\tau_r=0$ and
$\tau_i\to\infty$. Exponents describing these behaviors are defined and related
to weights $h_{r,s}$ of the extended Kac table for $r,s$ integers, but also
half-integers. Numerical simulations are also presented. Possible relationship
with recent works and conformal loop ensembles is discussed.


title:
New parallel programming language design: a bridge between brain models
  and multi-core/many-core computers?

abstract:
  The recurrent theme of this paper is that sequences of long temporal patterns
as opposed to sequences of simple statements are to be fed into computation
devices, being them (new proposed) models for brain activity or
multi-core/many-core computers. In such models, parts of these long temporal
patterns are already committed while other are predicted. This combination of
matching patterns and making predictions appears as a key element in producing
intelligent processing in brain models and getting efficient speculative
execution on multi-core/many-core computers. A bridge between these far-apart
models of computation could be provided by appropriate design of massively
parallel, interactive programming languages. Agapia is a recently proposed
language of this kind, where user controlled long high-level temporal
structures occur at the interaction interfaces of processes. In this paper
Agapia is used to link HTMs brain models with TRIPS multi-core/many-core
architectures.


title:
Balancing the Energy Budget between Star-Formation and AGN in High
  Redshift Infrared Luminous Galaxies

abstract:
  (abridged) We present deep Spitzer mid-infrared spectroscopy, along with 16,
24, 70, and 850um photometry, for 22 galaxies located in GOODS-N. The sample
spans a redshift range of 0.6 < z < 2.6, 24um flux densities between ~0.2-1.2
mJy, and consists of SMGs, AGN, and optically faint (z_AB > 25) sources. We
find that IR luminosities derived by fitting local SEDs with 24um photometry
alone are well matched to those when additional mid-infrared spectroscopic and
longer wavelength photometric data is used for galaxies having z < 1.4 and
24um-derived IR luminosities typically > 3x10^12 L_sun. However, for galaxies
in the redshift range between 1.4 < z < 2.6, typically having 24um-derived IR
luminosities > 3x10^12 L_sun, IR luminosities are overestimated by an average
factor of ~5 when SED fitting with 24um photometry alone. This result arises
partly due to the fact that high redshift galaxies exhibit PAH EQWs that are
large compared to local galaxies of similar luminosities. Using improved
estimates for the IR luminosities of these sources, we investigate whether
their IR emission is found to be in excess relative to that expected based on
extinction corrected UV SFRs, possibly suggesting the presence of an obscured
AGN. Through a spectral decomposition of IRS spectroscopic data, we are able to
isolate the fraction of IR luminosity arising from an AGN as opposed to star
formation activity. This fraction is only ~30% of the total IR luminosity among
the entire sample, on average. Of the sources identified as having mid-infrared
excesses, half are accounted for by using proper bolometric corrections while
half show the presence of obscured AGN. We do not find evidence for evolution
in the FIR-radio correlation over this redshift range, although the SMGs have
IR/radio ratios which are, on average, ~3 times lower than the nominal value.


abstract:
  In this paper, we investigate Jordan *-homomorphisms on $C^*$-algebras
associated with the following functional inequality
$\|f(\frac{b-a}{3})+f(\frac{a-3c}{3})+f(\frac{3a+3c-b}{3})\| \leq \|f(a)\|.$ We
moreover prove the superstability and the generalized Hyers-Ulam stability of
Jordan *-homomorphisms on $C^*$-algebras associated with the following
functional equation
$$f(\frac{b-a}{3})+f(\frac{a-3c}{3})+f(\frac{3a+3c-b}{3})=f(a).$$


title: On the Nature of Fossil Galaxy Groups: Are they really fossils ?

abstract:
  We use SDSS-DR4 photometric and spectroscopic data out to redshift z~0.1
combined with ROSAT All Sky Survey X-ray data to produce a sample of
twenty-five fossil groups (FGs), defined as bound systems dominated by a
single, luminous elliptical galaxy with extended X-ray emission. We examine
possible biases introduced by varying the parameters used to define the sample
and the main pitfalls are discussed. The spatial density of FGs, estimated via
the V/V_ MAX} test, is 2.83 x 10^{-6} h_{75}^3 Mpc^{-3} for L_x > 0.89 x 10^42
h_{75}^-2 erg/s consistent with Vikhlinin et al. (1999), who examined an X-ray
overluminous elliptical galaxy sample (OLEG). We compare the general properties
of FGs identified here with a sample of bright field ellipticals generated from
the same dataset. These two samples show no differences in the distribution of
neighboring faint galaxy density excess, distance from the red sequence in the
color-magnitude diagram, and structural parameters such as a$_{4}$ and internal
color gradients. Furthermore, examination of stellar populations shows that our
twenty-five FGs have similar ages, metallicities, and $\alpha$-enhancement as
the bright field ellipticals, undermining the idea that these systems represent
fossils of a physical mechanism that occurred at high redshift. Our study
reveals no difference between FGs and field ellipticals, suggesting that FGs
might not be a distinct family of true fossils, but rather the final stage of
mass assembly in the Universe.


title: Switched systems and the logical foundation of circuit theory

abstract:
  Switched (singular) systems become very common, which requires some revision
of the conceptual basis of system theory.


title:
Solution and stability of generalized mixed type cubic, quadratic and
  additive functional equation in quasi-Banach spaces

abstract:
  In this paper, we achieve the general solution and the generalized
  Hyers-Ulam-Rassias stability of the following functional equation
$$f(x+ky)+f(x-ky)=k^2f(x+y)+k^2f(x-y)+2(1-k^2)f(x)\eqno {2 cm}$$for fixed
integers $k$ with $k\neq0,\pm1$ in the quasi-Banach spaces.


title: Radio Signal by Galactic Dark Matter

abstract:
  An interesting strategy for indirect detection of Dark Matter comes through
the amounts of electrons and positrons usually emitted by DM pair annihilation.
The e+e- gyrating in the galactic magnetic field then produce secondary
synchrotron radiation. The radio emission from the galactic halo as well as
from its expected substructures if compared with the measured diffuse radio
background can provide constraints on the physics of WIMPs. In particular one
gets the bound of <sigma_A*v> = 10^{-24} cm^3 s^{-1} for a DM mass m_chi = 100
GeV even though sensibly depending on the astrophysical uncertainties.


title: Stability of homomorphisms and derivations in $C^*$-ternary algebras

abstract:
  In this paper, we investigate homomorphisms between $C^*$-ternary algebras
and derivations on $C^*$-ternary algebras, associated with the following
functional equation
$$f(\frac{x_2-x_1}{3})+f(\frac{x_1-3x_3}{3})+f(\frac{3x_1+3x_3-x_2}{3})=f(x_1).$$
Moreover, we prove the generalized Hyers-Ulam -Rassias stability of
homomorphisms in $C^*$-ternary algebras and of derivations on $C^*$-ternary
algebras.


title: n-Jordan homomorphisms

abstract:
  Let $n\in \Bbb N,$ and let $A,B$ be two rings. An additive map $h: A\to B$ is
called n-Jordan homomorphism if $h(a^n)=(h(a))^n$ for all $a \in {A}$. Every
Jordan homomorphism is an n-Jordan homomorphism, for all $n\geq 2,$ but the
converse is false, in general. In this paper we investigate the n-Jordan
homomorphisms on Banach algebras. Indeed some results related to continuity are
given as well.


title:
The Gravitational Shear--Intrinsic Ellipticity Correlation Functions of
  Luminous Red Galaxies in Observation and in the $\Lambda$CDM Model

abstract:
  We examine whether the gravitational shear--intrinsic ellipticity (GI)
correlation function of the luminous red galaxies (LRGs) can be modeled with
the distribution function of a misalignment angle advocated recently by Okumura
et al. For this purpose, we have accurately measured the GI correlation for the
LRGs in the Data Release 6 (DR6) of the Sloan Digital Sky Survey (SDSS), which
confirms the results of Hirata et al. who used the DR4 data. By comparing the
GI correlation functions in the simulation and in the observation, we find that
the GI correlation can be modeled in the current $\Lambda$CDM model if the
misalignment follows a Gaussian distribution with a zero mean and a typical
misalignment angle $\sigma_\theta=34.9^{+1.9}_{-2.1}$ degrees. We also find a
correlation between the axis ratios and intrinsic alignments of LRGs. This
effect should be taken into account in theoretical modeling of the GI and
intrinsic ellipticity--ellipticity correlations for weak lensing surveys.


title:
From Schoenberg to Pick-Nevanlinna: Toward a complete picture of the
  variogram class

abstract:
  We show that a large subclass of variograms is closed under products and that
some desirable stability properties, such as the product of special
compositions, can be obtained within the proposed setting. We introduce new
classes of kernels of Schoenberg-L\'{e}vy type and demonstrate some important
properties of rotationally invariant variograms.


title: On the chromatic number of random d-regular graphs

abstract:
  In this work we show that, for any fixed d, random d-regular graphs
asymptotically almost surely can be coloured with k colours, where k is the
smallest integer satisfying d<2(k-1)log(k-1). From previous lower bounds due to
Molloy and Reed, this establishes the chromatic number to be asymptotically
almost surely k-1 or k. If moreover d>(2k-3)log(k-1), then the value k-1 is
discarded and thus the chromatic number is exactly determined. Hence we improve
a recently announced result by Achlioptas and Moore in which the chromatic
number was allowed to take the value k+1. Our proof applies the small subgraph
conditioning method to the number of balanced k-colourings, where a colouring
is balanced if the number of vertices of each colour is equal.


title:
RAPID: A fast, high resolution, flux-conservative algorithm designed for
  planet-disk interactions

abstract:
  We describe a newly developed hydrodynamic code for studying accretion disk
processes. The numerical method uses a finite volume, nonlinear, Total
Variation Diminishing (TVD) scheme to capture shocks and control spurious
oscillations. It is second-order accurate in time and space and makes use of a
FARGO-type algorithm to alleviate Courant-Friedrichs-Lewy time step
restrictions imposed by the rapidly rotating inner disk region. OpenMP
directives are implemented enabling faster computations on shared-memory,
multi-processor machines. The resulting code is simple, fast and memory
efficient. We discuss the relevant details of the numerical method and provide
results of the code's performance on standard test problems. We also include a
detailed examination of the code's performance on planetary disk-planet
interactions. We show that the results produced on the standard problem setup
are consistent with a wide variety of other codes.


title:
Stability of a mixed type quadratic, cubic and quartic functional
  equation

abstract:
  In this paper, we obtain the general solution and the generalized Hyers-Ulam
Rassias stability of the functional equation
$$3(f(x+2y)+f(x-2y))=12(f(x+y)+f(x-y))+4f(3y)-18f(2y)+36f(y)-18f(x).$$


title: Charged particle display

abstract:
  An optical shutter based on charged particles is presented. The output light
intensity of the proposed device has an intrinsic dependence on the
interparticle spacing between charged particles, which can be controlled by
varying voltages applied to the control electrodes. The interparticle spacing
between charged particles can be varied continuously and this opens up the
possibility of particle based displays with continuous grayscale.


title: Entropy vs volume for pseudo-Anosov maps

abstract:
  We will discuss theoretical and experimental results concerning comparison of
entropy of pseudo-Anosov maps and volume of their mapping tori. Recent study of
Weil-Petersson geometry of the Teichm\"uller space tells us that they admit
linear inequalities for both sides under some bounded geometry condition. We
construct a family of pseudo-Anosov maps which violates one side of
inequalities under unbounded geometry setting, present an explicit bounding
constant for a punctured torus, and provide several observations based on
experiments.


title: Supertubes in Bubbling Backgrounds: Born-Infeld Meets Supergravity

abstract:
  We discuss two ways in which one can study two-charge supertubes as
components of generic three-charge, three-dipole charge supergravity solutions.
The first is using the Born-Infeld action of the supertubes, and the second is
via the complete supergravity solution. Even though the Born-Infeld description
is only a probe approximation, we find that it gives exactly the same essential
physics as the complete supergravity solution. Since supertubes can depend on
arbitrary functions, our analysis strengthens the evidence for the existence of
three-charge black-hole microstate geometries that depend on an infinite set of
parameters, and sets the stage for the computation of the entropy of these
backgrounds. We examine numerous other aspects of supertubes in three-charge,
three-dipole charge supergravity backgrounds, including chronology protection
during mergers, the contribution of supertubes to the charges and angular
momenta, and the enhancement of their entropy. In particular, we find that
entropy enhancement affects supertube fluctuations both along the internal and
the spacetime directions, and we prove that the charges that give the enhanced
entropy can be much larger than the asymptotic charges of the solution. We also
re-examine the embedding of five-dimensional black rings in Taub-NUT, and show
that in different coordinate patches a ring can correspond to different
four-dimensional black holes. Last, but not least, we show that all the
three-charge black hole microstate geometries constructed so far can be
embedded in AdS_3 x S^3, and hence can be related to states of the D1-D5 CFT.


title:
Swift-UVOT captures the earliest ultraviolet spectrum of a Gamma Ray
  Burst

abstract:
  We present the earliest ever ultraviolet spectrum of a gamma-ray burst (GRB)
as observed with the Swift-UVOT. The GRB 081203A spectrum was observed for 50
seconds with the UV grism starting 251 seconds after the Swift-BAT trigger when
the GRB was of u ~13.4 mag and still rising to its peak optical brightness. The
UV grism spectrum shows a damped Ly-alpha line, Ly-beta, and the Lyman
continuum break at a redshift z = 2.05 +/- 0.01. A model fit to the Lyman
absorption implies log N(HI) = 22.0 +/- 0.2 cm-2, which is typical for GRB host
galaxies with damped Ly-alpha absorbers. This observation of GRB 081203A
demonstrates that for GRBs brighter than v ~14 mag and with 0.5 < z < 3.5 the
UVOT will be able to provide redshifts, and probe for damped Ly-alpha absorbers
within 4-6 minutes from the time of the Swift-BAT trigger.


title: Zero entropy invariant measures for some skew product diffeomorphisms

abstract:
  In this paper we study some skew product diffeomorphisms with nonuniformly
hyperbolic structure along fibers. We show that there is an invariant measure
with zero entropy which has atomic conditional measures along fibers.


title:
Asymmetric parametric amplification in nonlinear left-handed
  transmission lines

abstract:
  We study parametric amplification in nonlinear left-handed transmission
lines, which serve as model systems for nonlinear negative index metamaterials.
We experimentally demonstrate amplification of a weak pump signal in three
regimes: with the signal in the left-handed band, with the signal in the stop
band, and with the signal at a defect frequency. In particular, we demonstrate
the amplification of the incident wave by up to 15dB in the left-handed regime.


title:
Nucleosynthetic osmium isotope anomalies in acid leachates of the
  Murchison meteorite

abstract:
  We present osmium isotopic results obtained by sequential leaching of the
Murchison meteorite, which reveal the existence of very large internal
anomalies of nucleosynthetic origin. The Os isotopic anomalies are correlated,
and can be explained by the variable contributions of components derived from
the s, r and p-processes of nucleosynthesis. Much of the s-process rich osmium
is released by relatively mild leaching, suggesting the existence of an easily
leachable s-process rich presolar phase, or alternatively, of a chemically
resistant r-process rich phase. The s-process composition of Os released by
mild leaching diverges slightly from that released by aggressive digestion
techniques, perhaps suggesting that the presolar phases attacked by these
differing procedures condensed in different stellar environments. The
correlation between 190Os and 188Os can be used to constrain the s-process
190Os/188Os ratio to be 1.275 pm 0.043. Such a ratio can be reproduced in a
nuclear reaction network for a MACS value for 190Os of ~200 pm 22 mbarn at 30
keV. We also present evidence for extensive internal variation of 184Os
abundances in the Murchison meteorite. This suggests that p process rich
presolar grains (e.g., supernova condensates) may be present in meteorites in
sufficient quantities to influence the Os isotopic compositions of the
leachates.


title: Spatiotemporal structures in aging and rejuvenating glasses

abstract:
  Complex spatiotemporal structures develop during the process of aging glasses
after cooling and of rejuvenating glasses upon heating. The key to
understanding these structures is the interplay between the activated
reconfiguration events which generate mobility and the transport of mobility.
These effects are both accounted for by combining the random first order
transition theory of activated events with mode coupling theory in an
inhomogeneous setting. The predicted modifications by mobility transport of the
time course of the aging regime are modest. In contrast, the rejuvenation
process is strongly affected through the propagation of fronts of enhanced
mobility originating from the initial reconfiguration events. The structures in
a rejuvenating glass resemble flames. An analysis along the lines of combustion
theory provides an estimate of the front propagation speed. Heterogeneous
rejuvenation naturally should occur for glasses with free surfaces. The analogy
with combustion also provides a new way of looking at the uptake of diluents by
glasses described by case II and super case II diffusion.


title:
Braided Bundles and Compact Coils: The Structure and Thermodynamics of
  Hexagonally-Packed, Chiral Filament Assemblies

abstract:
  Molecular chirality frustrates the two-dimensional assembly of filamentous
molecules, a fact that reflects the generic impossibility of imposing a global
twisting of layered materials. We explore the consequences of this frustration
for hexagonally-ordered assemblies of chiral filaments that are {\it finite} in
lateral dimension. Specifically, we employ a continuum-elastic description of
cylindrical bundles of filaments, allowing us to consider the most general
resistance to and preference for chiral ordering of the assembly. We explore
two distinct mechanisms by which chirality at the molecular scale of the
filament frustrates the assembly into aggregates. In the first, chiral
interactions between filaments impart an overall twisting of filaments around
the central axis of the bundle. In the second, we consider filaments that are
inherently helical in structure, imparting a writhing geometry to the central
axis. For both mechanisms, we find that a thermodynamically-stable state of
dispersed bundles of {\it finite} width appears close to, but below, the point
of bulk filament condensation. The range of thermodynamic stability of
dispersed bundles is sensitive only to the elastic cost and preference for
chiral filament packing. The self-limited assembly of chiral filaments has
particular implications for a large class of biological molecules -- DNA,
filamentous proteins, viruses, bacterial flagella -- which are universally
chiral and are observed to form compact bundles under a broad range of
conditions.


title: Equilibria in the secular, non-coplanar two-planet problem

abstract:
  We investigate the secular dynamics of a planetary system composed of the
parent star and two massive planets in mutually inclined orbits. The dynamics
are investigated in wide ranges of semi-major axes ratios (0.1-0.667), and
planetary masses ratios (0.25-2) as well as in the whole permitted ranges of
the energy and total angular momentum. The secular model is constructed by
semi-analytic averaging of the three-body system. We focus on equilibria of the
secular Hamiltonian (periodic solutions of the full system), and we analyze
their stability. We attempt to classify families of these solutions in terms of
the angular momentum integral. We identified new equilibria, yet unknown in the
literature. Our results are general and may be applied to a wide class of
three-body systems, including configurations with a star and brown dwarfs and
sub-stellar objects. We also describe some technical aspects of the
semi-numerical averaging. The HD 12661 planetary system is investigated as an
example configuration.


title: Beam Spin Asymmetries in DVCS with CLAS at 4 .8 GeV

abstract:
  We report measurements of the beam spin asymmetry in Deeply Virtual Compton
Scattering (DVCS) at an electron beam energy of 4.8 GeV using the CLAS detector
at the Thomas Jefferson National Accelerator Facility. The DVCS beam spin
asymmetry has been measured in a wide range of kinematics, 1(GeV/c)$^2$
$<Q^2<2.8$(GeV/c)$^2$, $0.12<x_B<0.48$, and 0.1 (GeV/c)$^2$
$<-t<0.8$(GeV/c)$^2$, using the reaction \pEpX. The number of
H$(e,e^{\prime}\gamma p)$ and H$(e,e^{\prime}\pi^0 p)$ events are separated in
each $(Q^2,x_B,t)$ bin by a fit to the line shape of the H$(e,e^{\prime}p)X$
$M_x^2$ distribution. The validity of the method was studied in detail using
experimental and simulated data. It was shown, that with the achieved missing
mass squared resolution and the available statistics, the separation of DVCS-BH
and $\pi^0$ events can reliably be done with less than 5% uncertainty. The
$Q^2$- and $t$-dependences of the $\sin\phi$ moments of the asymmetry are
extracted and compared with theoretical calculations.


title: Spitzer Planet Limits around the Pulsating White Dwarf GD66

abstract:
  We present infrared observations in search of a planet around the white
dwarf, GD66. Time-series photometry of GD66 shows a variation in the arrival
time of stellar pulsations consistent with the presence of a planet with mass >
2.4Mj. Any such planet is too close to the star to be resolved, but the
planet's light can be directly detected as an excess flux at 4.5um. We observed
GD66 with the two shorter wavelength channels of IRAC on Spitzer but did not
find strong evidence of a companion, placing an upper limit of 5--7Mj on the
mass of the companion, assuming an age of 1.2--1.7Gyr.


title: Acoustic Metameterial with Negative Modulus

abstract:
  We present experimental and theoretical results on an acoustic metamaterial
that exhibits negative effective modulus in a frequency range from 0 to 450 Hz.
One-dimensional acoustic metamaterial with an array of side holes on a tube was
fabricated. We observed that acoustic waves above 450 Hz propagated well in
this structure, but no sound below 450 Hz passed through. The frequency
characteristics of the metamaterial has the same form as that of the
permittivity in metals due to the plasma oscillation. We also provide a theory
to explain the experimental results.


title: A picogram and nanometer scale photonic crystal opto-mechanical cavity

abstract:
  We describe the design, fabrication, and measurement of a cavity
opto-mechanical system consisting of two nanobeams of silicon nitride in the
near-field of each other, forming a so-called "zipper" cavity. A photonic
crystal patterning is applied to the nanobeams to localize optical and
mechanical energy to the same cubic-micron-scale volume. The picrogram-scale
mass of the structure, along with the strong per-photon optical gradient force,
results in a giant optical spring effect. In addition, a novel damping regime
is explored in which the small heat capacity of the zipper cavity results in
blue-detuned opto-mechanical damping.


title: Negative Effective Density in An Acoustic Metamaterial

abstract:
  We report theoretical and experimental results for a new type of homogenized
acoustic metamaterials with negative effective mass density. We constructed
one-dimensional metamaterial, which is a tube with an array of very thin
elastic membranes placed inside. This structure exhibited negative effective
density in the frequency range from 0 to 735 Hz. The experimental result is in
excellent agreement with our theoretical model that predicts negative effective
density below a cut-off frequency. The frequency characteristics of this
effective density is analogous to that of the permittivity of the
electromagnetic plasma oscillation.


title:
Spin, Bose, and Non-Fermi Liquid Metals in Two Dimensions: Accessing via
  Multi-Leg Ladders

abstract:
  Characterizing and accessing quantum phases of itinerant bosons or fermions
in two dimensions (2D) that exhibit singular structure along surfaces in
momentum space but have no quasi-particle description remains as a central
challenge in the field of strongly correlated physics. Fortuitously, signatures
of such 2D strongly correlated phases are expected to be manifest in
quasi-one-dimensional "$N$-leg ladder" systems. The ladder discretization of
the transverse momentum cuts through the 2D surface, leading to a quasi-1D
descendant state with a set of low-energy modes whose number grows with the
number of legs and whose momenta are inherited from the 2D surfaces. These
multi-mode quasi-1D liquids constitute a new and previously unanticipated class
of quantum states interesting in their own right. But more importantly they
carry a distinctive quasi-1D "fingerprint" of the parent 2D quantum fluid
state. This can be exploited to access the 2D phases from controlled numerical
and analytical studies in quasi-1D models. The preliminary successes and future
prospects in this endeavor will be briefly summarized.


title: Chiral susceptibility and the scalar Ward identity

abstract:
  The chiral susceptibility is given by the scalar vacuum polarisation at zero
total momentum. This follows directly from the expression for the vacuum quark
condensate so long as a nonperturbative symmetry preserving truncation scheme
is employed. For QCD in-vacuum the susceptibility can rigorously be defined via
a Pauli-Villars regularisation procedure. Owing to the scalar Ward identity,
irrespective of the form or Ansatz for the kernel of the gap equation, the
consistent scalar vertex at zero total momentum can automatically be obtained
and hence the consistent susceptibility. This enables calculation of the chiral
susceptibility for markedly different vertex Ansaetze. For the two cases
considered, the results were consistent and the minor quantitative differences
easily understood. The susceptibility can be used to demarcate the domain of
coupling strength within a theory upon which chiral symmetry is dynamically
broken. Degenerate massless scalar and pseudoscalar bound-states appear at the
critical coupling for dynamical chiral symmetry breaking.


title: Stationary and transient leakage current in the Pauli spin blockade

abstract:
  We study the effects of cotunneling and a non-uniform Zeeman splitting on the
stationary and transient leakage current through a double quantum dot in the
Pauli spin blockade regime. We find that the stationary current due to
cotunneling vanishes at low temperature and large applied magnetic field,
allowing for the dynamical preparation of a pure spin ground state, even at
large voltage bias. Additionally, we analyze current that flows between
blocking events, characterized, in general, by a fractional effective charge
$e^*$. This charge can be used as a sensitive probe of spin relaxation
mechanisms and can be used to determine the visibility of Rabi oscillations.


title: Electroweak scale neutrinos and Higgses

abstract:
  We present two different models with electroweak scale right-handed
neutrinos. One of the models is created under the constraint that any addition
to the Standard Model must not introduce new higher scales. The model contains
right-handed neutrinos with electroweak scale masses and a lepton number
violating singlet scalar field. The scalar phenomenology is also presented. The
second model is a triplet Higgs model where again the right-handed neutrinos
have electroweak scale masses. In this case the model has a rich scalar
phenomenology and in particular we present the analysis involving the doubly
charged Higgs.


title: Pattern Speeds and Galaxy Morphology

abstract:
  The morphology of a disk galaxy is closely linked to its kinematic state.
This is because density wave features are likely made of spontaneously-formed
modes which are allowed to arise in the galactic resonant cavity of a
particular basic disk state. The pattern speed of a density wave is an
important parameter that characterizes the wave and its associated resonances.
Numerical simulations by various authors have enabled us to interpret some
galaxies in terms of high or low pattern speeds. The potential-density
phase-shift method for locating corotation radii is an effective new tool for
utilizing galaxy morphology to determine the kinematic properties of galaxies.
The dynamical mechanism underlying this association is also responsible for the
secular evolution of galaxies. We describe recent results from the application
of this new method to more than 150 galaxies in the Ohio State University
Bright Galaxy Survey and other datasets.


title: Fermi LAT Observations of the Vela Pulsar

abstract:
  The Vela pulsar is the brightest persistent source in the GeV sky and thus is
the traditional first target for new gamma-ray observatories. We report here on
initial Fermi Large Area Telescope observations during verification phase
pointed exposure and early sky survey scanning. We have used the Vela signal to
verify Fermi timing and angular resolution. The high quality pulse profile,
with some 32,400 pulsed photons at E>0.03 GeV, shows new features, including
pulse structure as fine as 0.3ms and a distinct third peak, which shifts in
phase with energy. We examine the high energy behavior of the pulsed emission;
initial spectra suggest a phase-averaged power law index of
Gamma=1.51{+0.05/-0.04} with an exponential cut-off at E_c=2.9+/-0.1 GeV.
Spectral fits with generalized cut-offs of the form e^{-(E/E_c)^b} require b<1,
which is inconsistent with magnetic pair attenuation, and thus favor outer
magnetosphere emission models. Finally, we report on upper limits to any
unpulsed component, as might be associated with a surrounding synchrotron wind
nebula (PWN).


title:
Anomalous uniform domain in a twisted nematic cell constructed from
  micropatterned surfaces

abstract:
  We have discovered an optically uniform type of domain that occurs in Twisted
Nematic (TN) cells that are constructed from substrates chemically patterned
with stripes via microcontact printing of Self-Assembled Monolayers (SAM); such
domains do not occur in TN cells constructed from uniform substrates. In such a
cell, the azimuthal anchoring at the substrates is due to the elastic
anisotropy of the liquid crystal rather than the conventional rubbing
mechanism. A model is presented that predicts the relative stability of the
twisted and anomalous states as a function of the material and design
parameters.


title:
The Northern Sky Optical Cluster Survey III: A Cluster Catalog Covering
  Pi Steradians

abstract:
  We present the complete galaxy cluster catalog from the Northern Sky Optical
Cluster Survey, a new, objectively defined catalog of candidate galaxy clusters
at z<0.25 drawn from the Digitized Second Palomar Observatory Sky Survey
(DPOSS). The data presented here cover the Southern Galactic Cap, as well as
the less-well calibrated regions of the Northern Galactic Cap. In addition, due
to improvements in our cluster finder and measurement methods, we provide an
updated catalog for the well-calibrated Northern Galactic Cap region previously
published in Paper II. The complete survey covers 11,411 square degrees, with
over 15,000 candidate clusters. We discuss improved photometric redshifts,
richnesses and optical luminosities which are provided for each cluster. A
variety of substructure measures are computed for a subset of over 11,000
clusters. We also discuss the derivation of dynamical radii r_200 and its
relation to cluster richness. A number of consistency checks between the three
areas of the survey are also presented, demonstrating the homogeneity of the
catalog over disjoint sky areas. We perform extensive comparisons to existing
optically and X-ray selected cluster catalogs, and derive new X-ray
luminosities and temperatures for a subset of our clusters. We find that the
optical and X-ray luminosities are well correlated, even using relatively
shallow ROSAT All Sky Survey and DPOSS data. This survey provides a good
comparison sample to the MaxBCG catalog based on Sloan Digital Sky Survey Data,
and complements that survey at low redshifts 0.07<z<0.1.


title: Paired states in spin-imbalanced atomic Fermi gases in one dimension

abstract:
  A growing expertise to engineer, manipulate and probe different cold-atom
analogs of electronic condensed matter systems allows to probe properties of
exotic pairing. We study paired states of spin-imbalanced ultracold atomic
system of fermions with attractive short-range interactions in one-dimensional
traps. Calculations are done using the Bethe Ansatz technique and the trap is
incorporated into the solution via a local density approximation. The
thermodynamic-Bethe-Ansatz equations are solved numerically and different local
density profiles are calculated for zero and finite temperatures. A procedure
to identify the homogeneous-system phase diagram using local density profiles
in the trap is also proposed. Such scheme would be immediately useful for the
experiments.

categories: cond-mat.other cond-mat.str-el cond-mat.supr-con physics.atom-ph


title:
Parallelization of Markov chain generation and its application to the
  multicanonical method

abstract:
  We develop a simple algorithm to parallelize generation processes of Markov
chains. In this algorithm, multiple Markov chains are generated in parallel and
jointed together to make a longer Markov chain. The joints between the
constituent Markov chains are processed using the detailed balance. We apply
the parallelization algorithm to multicanonical calculations of the
two-dimensional Ising model and demonstrate accurate estimation of
multicanonical weights.

categories: cond-mat.stat-mech hep-lat physics.bio-ph physics.comp-ph


title:
Two-temperature relaxation and melting after absorption of femtosecond
  laser pulse

abstract:
  The theory and experiments concerned with the electron-ion thermal relaxation
and melting of overheated crystal lattice constitute the subject of this paper.
The physical model includes two-temperature equation of state, many-body
interatomic potential, the electron-ion energy exchange, electron thermal
conductivity, and optical properties of solid, liquid, and two phase
solid-liquid mixture. Two-temperature hydrodynamics and molecular dynamics
codes are used. An experimental setup with pump-probe technique is used to
follow evolution of an irradiated target with a short time step 100 fs between
the probe femtosecond laser pulses. Accuracy of measurements of reflection
coefficient and phase of reflected probe light are ~1% and $\sim 1\un{nm}$,
respectively. It is found that,
  {\it firstly}, the electron-electron collisions make a minor contribution to
a light absorbtion in solid Al at moderate intensities;
  {\it secondly}, the phase shift of a reflected probe results from heating of
ion subsystem and kinetics of melting of Al crystal during $0<t<4\un{ps},$
where $t$ is time delay between the pump and probe pulses measured from the
maximum of the pump;
  {\it thirdly} the optical response of Au to a pump shows a marked contrast to
that of Al on account of excitation of \textit{d}-electrons


title: Faddeev equations: a view of baryon properties

abstract:
  We present a calculation of the three-quark core contribution to the mass of
the Delta-baryon in a Poincare-covariant Faddeev framework. A consistent setup
for the dressed-quark propagator, the quark-quark and quark-diquark
interactions is used, where all the ingredients are solutions of their
respective Dyson-Schwinger or Bethe-Salpeter equations in rainbow-ladder
truncation. We discuss the evolution of the Delta mass with the current-quark
mass and compare to the previously obtained mass of the nucleon.


title: Shape Fitting on Point Sets with Probability Distributions

abstract:
  A typical computational geometry problem begins: Consider a set P of n points
in R^d. However, many applications today work with input that is not precisely
known, for example when the data is sensed and has some known error model. What
if we do not know the set P exactly, but rather we have a probability
distribution mu_p governing the location of each point p in P?
  Consider a set of (non-fixed) points P, and let mu_P be the probability
distribution of this set. We study several measures (e.g. the radius of the
smallest enclosing ball, or the area of the smallest enclosing box) with
respect to mu_P. The solutions to these problems do not, as in the traditional
case, consist of a single answer, but rather a distribution of answers. We
describe several data structures that approximate distributions of answers for
shape fitting problems.
  We provide simple and efficient randomized algorithms for computing all of
these data structures, which are easy to implement and practical. We provide
some experimental results to assert this. We also provide more involved
deterministic algorithms for some of these data structures that run in time
polynomial in n and 1/eps, where eps is the approximation factor.


title: On general Cwikel-Lieb-Rozenblum and Lieb-Thirring inequalities

abstract:
  These classical inequalities allow one to estimate the number of negative
eigenvalues and the sums $S_{\gamma}=\sum |\lambda_i|^{\gamma}$ for a wide
class of Schr\"{o}dinger operators. We provide a detailed proof of these
inequalities for operators on functions in metric spaces using the classical
Lieb approach based on the Kac-Feynman formula. The main goal of the paper is a
new set of examples which include perturbations of the Anderson operator,
operators on free, nilpotent and solvable groups, operators on quantum graphs,
Markov processes with independent increments. The study of the examples
requires an exact estimate of the kernel of the corresponding parabolic
semigroup on the diagonal. In some cases the kernel decays exponentially as
$t\to \infty $. This allows us to consider very slow decaying potentials and
obtain some results that are precise in the logarithmical scale.


title: A Growing Self-Organizing Network for Reconstructing Curves and Surfaces

abstract:
  Self-organizing networks such as Neural Gas, Growing Neural Gas and many
others have been adopted in actual applications for both dimensionality
reduction and manifold learning. Typically, in these applications, the
structure of the adapted network yields a good estimate of the topology of the
unknown subspace from where the input data points are sampled. The approach
presented here takes a different perspective, namely by assuming that the input
space is a manifold of known dimension. In return, the new type of growing
self-organizing network presented gains the ability to adapt itself in way that
may guarantee the effective and stable recovery of the exact topological
structure of the input manifold.


title: The astronomical units

abstract:
  The IAU-1976 System of astronomical constants includes three astronomical
units (i.e. for time, mass and length). This paper reports on the status of the
astronomical unit of length (ua) and mass (MSun) within the context of the
recent IAU Resolutions on reference systems and the use of modern observations
in the solar system. We especially look at a possible re-definition of the ua
as an astronomical unit of length defined trough a fixed relation to the SI
metre by a defining number.


title:
Cyclotomic FFT of Length 2047 Based on a Novel 11-point Cyclic
  Convolution

abstract:
  In this manuscript, we propose a novel 11-point cyclic convolution algorithm
based on alternate Fourier transform. With the proposed bilinear form, we
construct a length-2047 cyclotomic FFT.


title:
Cross-Correlation between Damped Ly-alpha Systems and Ly-break Galaxies
  in Cosmological SPH Simulations

abstract:
  We calculate the cross-correlation function (CCF) between damped Ly-a systems
(DLAs) and Lyman break galaxies (LBGs) using cosmological hydrodynamic
simulations at z=3. We compute the CCF with two different methods. First, we
assume that there is one DLA in each dark matter halo if its DLA cross section
is non-zero. In our second approach we weight the pair-count by the DLA cross
section of each halo, yielding a cross-section-weighted CCF. We also compute
the angular CCF for direct comparison with observations. Finally, we calculate
the auto-correlation functions of LBGs and DLAs, and their bias against the
dark matter distribution. For these different approaches, we consistently find
that there is good agreement between our simulations and observational
measurements by Cooke et al. and Adelberger et al. Our results thus confirm
that the spatial distribution of LBGs and DLAs can be well described within the
framework of the concordance Lambda CDM model. We find that the correlation
strengths of LBGs and DLAs are consistent with the actual observations, and in
the case of LBGs it is higher than would be predicted by low-mass galaxy merger
models.


title:
Electrical properties of vanadium oxide subject to hydrogen plasma
  treatment

abstract:
  The effect of doping with hydrogen on the electrical properties of vanadium
oxide is studied. For vanadium oxide films, subject to cold hydrogen plasma
treatment, the temperature dependence of resistance with a maximum at T ~ 100 K
is observed. Also, the dependence of the a.c. resistance on frequency is
studied. A strategy for fabrication new superconducting materials is discussed.


title: Resistance noise in electrically biased bilayer graphene

abstract:
  We demonstrate that the low-frequency resistance fluctuations, or noise, in
bilayer graphene is strongly connected to its band structure, and displays a
minimum when the gap between the conduction and valence band is zero. Using
double-gated bilayer graphene devices we have tuned the zero gap and charge
neutrality points independently, which offers a versatile mechanism to
investigate the low-energy band structure, charge localization and screening
properties of bilayer graphene.


title:
An XMM-Newton Spectral and Timing Study of IGR J16207-5129: An Obscured
  and Non-Pulsating HMXB

abstract:
  We report on a 12 hr XMM-Newton observation of the supergiant High-Mass X-ray
Binary IGR J16207-5129. This is only the second soft X-ray (0.4-15 keV, in this
case) study of the source since it was discovered by the INTEGRAL satellite.
The average energy spectrum is very similar to those of neutron star HMXBs,
being dominated by a highly absorbed power-law component with a photon index of
1.15. The spectrum also exhibits a soft excess below 2 keV and an iron Kalpha
emission line at 6.39+/-0.03 keV. For the primary power-law component, the
column density is 1.19E23 cm^-2, indicating local absorption, likely from the
stellar wind, and placing IGR J16207-5129 in the category of obscured IGR
HMXBs. The source exhibits a very high level of variability with an rms noise
level of 64%+/-21% in the 0.0001 to 0.05 Hz frequency range. Although the
energy spectrum suggests that the system may harbor a neutron star, no
pulsations are detected with a 90% confidence upper limit of 2% in a frequency
range from 0.0001 to 88 Hz. We discuss similarities between IGR J16207-5129 and
other apparently non-pulsating HMXBs, including other IGR HMXBs as well as 4U
2206+54 (but see arXiv:0812.2365) and 4U 1700-377.


title:
Parallel Algorithm for Solving Kepler's Equation on Graphics Processing
  Units: Application to Analysis of Doppler Exoplanet Searches

abstract:
  [Abridged] We present the results of a highly parallel Kepler equation solver
using the Graphics Processing Unit (GPU) on a commercial nVidia GeForce 280GTX
and the "Compute Unified Device Architecture" programming environment. We apply
this to evaluate a goodness-of-fit statistic (e.g., chi^2) for Doppler
observations of stars potentially harboring multiple planetary companions
(assuming negligible planet-planet interactions). We tested multiple
implementations using single precision, double precision, pairs of single
precision, and mixed precision arithmetic. We find that the vast majority of
computations can be performed using single precision arithmetic, with selective
use of compensated summation for increased precision. However, standard single
precision is not adequate for calculating the mean anomaly from the time of
observation and orbital period when evaluating the goodness-of-fit for real
planetary systems and observational data sets. Using all double precision, our
GPU code outperforms a similar code using a modern CPU by a factor of over 60.
Using mixed-precision, our GPU code provides a speed-up factor of over 600,
when evaluating N_sys > 1024 models planetary systems each containing N_pl = 4
planets and assuming N_obs = 256 observations of each system. We conclude that
modern GPUs also offer a powerful tool for repeatedly evaluating Kepler's
equation and a goodness-of-fit statistic for orbital models when presented with
a large parameter space.


title:
Exact solution of the infinite-U Hubbard problem and other models in one
  dimension

abstract:
  An interacting spin-fermion model is exactly solved on an open chain. In a
certain representation, it is the nearest-neighbor Hubbard model in the limit
of infinite $U$ (local interaction). Exact solution of its complete energy
eigen-spectrum is accomplished by introducing a unitary transformation which
maps the original problem to a tight-binding model of the fermions only.
Physically, the exact solution implies the absence of Nagaoka ferromagnetism in
the ground state for arbitrary electron densities. The present method solves a
class of very general models exactly. Few more problems are discussed as an
application of this unitary transform method.


title: Generalizations of Chung-Feller Theorem

abstract:
  The classical Chung-Feller theorem [2] tells us that the number of Dyck paths
of length $n$ with flaws $m$ is the $n$-th Catalan number and independent on
$m$. L. Shapiro [7] found the Chung-Feller properties for the Motzkin paths. In
this paper, we find the connections between these two Chung-Feller theorems. We
focus on the weighted versions of three classes of lattice paths and give the
generalizations of the above two theorems. We prove the Chung-Feller theorems
of Dyck type for these three classes of lattice paths and the Chung-Feller
theorems of Motzkin type for two of these three classes. From the obtained
results, we find an interesting fact that many lattice paths have the
Chung-Feller properties of both Dyck type and Motzkin type.


title:
Poisson commutator-anticommutator brackets for ray tracing and
  longitudinal imaging via geometric algebra

abstract:
  We use the vector wedge product in geometric algebra to show that Poisson
commutator brackets measure preservation of phase space areas. We also use the
vector dot product to define the Poisson anticommutator bracket that measures
the preservation of phase space angles. We apply these brackets to the paraxial
meridional complex height-angle ray vectors that transform via a 2x2 matrix,
and we show that this transformation preserves areas but not angles in phase
space. The Poisson brackets here are expressed in terms of the coefficients of
the ABCD matrix. We also apply these brackets to the distance-height ray
vectors measured from the input and output sides of the optical system. We show
that these vectors obey a partial Moebius transformation, and that this
transformation preserves neither areas nor angles. The Poisson brackets here
are expressed in terms of the transverse and longitudinal magnifications.