title:
Beta-delayed neutron and gamma-ray spectroscopy of 17C utilizing
  spin-polarized 17B

abstract:
  Excited states in 17C were investigated through the measurement of
beta?-delayed neutrons and gamma rays emitted in the ? decay of 17B. In the
measurement, three negative-parity states and two inconclusive states, were
identified in 17C above the neutron threshold energy, and seven gamma-lines
were identified in a beta?-delayed multiple neutron emission of the 17B ?
decay. From these transitions, the beta?-decay scheme of 17B was determined. In
the present work, the fibeta-NMR technique is combined with the ?-delayed
particle measurements using a fragmentation-induced spin-polarized 17B beam.
This new scheme allows us to determine the spin parity of beta?-decay feeding
excited states based on the difference in the discrete fibeta-decay asymmetry
parameters, provided the states are connected through the Gamow-Teller
transition. In this work, 1/2-, 3/2-, and (5/2-) are assigned to the observed
states at Ex = 2.71(2), 3.93(2), and 4.05(2) MeV in 17C, respectively.


title:
Total and selective reuse of Krylov subspaces for the resolution of
  sequences of nonlinear structural problems

abstract:
  This paper deals with the definition and optimization of augmentation spaces
for faster convergence of the conjugate gradient method in the resolution of
sequences of linear systems. Using advanced convergence results from the
literature, we present a procedure based on a selection of relevant
approximations of the eigenspaces for extracting, selecting and reusing
information from the Krylov subspaces generated by previous solutions in order
to accelerate the current iteration. Assessments of the method are proposed in
the cases of both linear and nonlinear structural problems.


title: A Verified Approach for Checking Real-Time Specification Patterns

abstract:
  We propose a verified approach to the formal verification of timed properties
using model-checking techniques. We focus on properties expressed using
real-time specification patterns, which can be viewed as a subset of timed
temporal logics that includes properties commonly found during the analysis of
reactive systems. Our model-checking approach is based on the use of observers
in order to transform the verification of timed patterns into the verification
of simpler LTL formulas. While the use of observers for model-checking is quite
common, our contribution is original in several ways. First, we define a formal
framework to verify that our observers are correct and non-intrusive. Second,
we define different classes of observers for each pattern and use a pragmatic
approach in order to select the most efficient candidate in practice. This
approach is implemented in an integrated verification tool chain for the Fiacre
language.


title: Phase-sensitive narrowband heterodyne holography

abstract:
  We report on amplitude and phase imaging of out-of-plane sinusoidal surface
vibration at nanometer scales with a heterodyne holographic interferometer. The
originality of the proposed method is to make use of a multiplexed local
oscillator to address several optical sidebands into the temporal bandwidth of
a sensor array. This process is called coherent frequency-division
multiplexing. It enables simultaneous recording and pixel-to-pixel division of
sideband holograms, which permits quantitative wide-field mapping of optical
phase modulation depths. Additionally, a linear frequency chirp ensures the
retrieval of the local mechanical phase shift of the vibration with respect to
the excitation signal. The proposed approach is validated by quantitative
motion characterization of the lamellophone of a musical box, behaving as a
group of harmonic oscillators, under weak sinusoidal excitation. Images of the
vibration amplitude versus excitation frequency show the resonance of the
nanometric flexural response of one individual cantilever, at which a phase hop
is measured. \copyright Optical Society of America.


title: An Experiment on Parallel Model Checking of a CTL Fragment

abstract:
  We propose a parallel algorithm for local, on the fly, model checking of a
fragment of CTL that is well-suited for modern, multi-core architectures. This
model-checking algorithm takes bene t from a parallel state space construction
algorithm, which we described in a previous work, and shares the same basic set
of principles: there are no assumptions on the models that can be analyzed; no
restrictions on the way states are distributed; and no restrictions on the way
work is shared among processors. We evaluate the performance of diff erent
versions of our algorithm and compare our results with those obtained using
other parallel model checking tools. One of the most novel contributions of
this work is to study a space-e fficient variant for CTL model-checking that
does not require to store the whole transition graph but that operates on a
reverse spanning tree.


title: Real-Time Specification Patterns and Tools

abstract:
  An issue limiting the adoption of model checking technologies by the industry
is the ability, for non-experts, to express their requirements using the
property languages supported by verification tools. This has motivated the
definition of dedicated assertion languages for expressing temporal properties
at a higher level. However, only a limited number of these formalisms support
the definition of timing constraints. In this paper, we propose a set of
specification patterns that can be used to express real-time requirements
commonly found in the design of reactive systems. We also provide an integrated
model checking tool chain for the verification of timed requirements on TTS, an
extension of Timed Petri Nets with data variables and priorities.


title:
Constraints on anomalous $tcZ$ coupling from $\bar B \to \bar K^* \mu^+
  \mu^-$ and $B_s \to \mu^+ \mu^-$ decays

abstract:
  In this paper, we analyze the possible anomalous $tcZ$ coupling effects in
the $b \to s $ mediated decays $\bar B \to \bar K^* \mu^+ \mu^-$ and $B_s \to
\mu^+ \mu^-$. After exploiting the available experimental data, the combined
constraints on the anomalous coupling $X_{ct}^L$ are derived. It is found that,
the bound on the magnitude $|X_{ct}^L|$ is dominated by the branching ratios of
these two decays. Furthermore, one sign-flipped solution is excluded by the
longitudinal fraction of $\bar B \to \bar K^* \mu^+ \mu^-$ at the low dilepton
mass region. After considering the combined constraints, for general complex
coupling $X_{ct}^L$, the predicted upper bound on $\mathcal B (t \to cZ)$ are
compatible with that from the recent CMS direct search. In particular, for the
case of real coupling $X_{ct}^L$, the upper bound reads $\mathcal B (t \to
cZ)<1.0\times 10^{-4}$, which is much lower than the current CMS bound but
still accessible at the LHC. With improved measurements at the LHC, the colser
correlations between the $t \to cZ$ and $b \to s$ mediated (semi-) leptonic
decays are expected in the near future.


title: Axino dark matter with R-parity violation and 130 GeV gamma-ray line

abstract:
  We show that decaying axino dark matter with R-parity violation can explain
the observed excess of the 130GeV gamma-ray line from the Galactic center in
the Fermi data. The branching fraction of the axino decay into monochromatic
photons can be O(1), and constraints from continuum gamma-rays and the
anti-proton flux are ameliorated. The Peccei-Quinn scale of
$O(10^{13}-10^{14})$\,GeV and the R-parity violation parameter of
$O(10^{-12}-10^{-11})$ are cosmologically favored.


title: Complex quantum hydrodynamics with teleportation

abstract:
  It is shown how the Schrodinger equation can be transformed to a complex
quantum Navier-Stokes equation with imaginary dilatational viscosity. The
self-diffusion in quantum gases is described by this complex quantum
hydrodynamics and the quantum Marangoni effect is introduced. The density
matrix operator and Wigner function equations, corresponding to quantum
hydrodynamics, are described. Finally, the quantum teleportation in time is
also discussed via a non-relativistic version of the Majorana equation.


title:
Structure of the Large Magellanic Cloud from the Near Infrared
  magnitudes of Red Clump stars

abstract:
  The structural parameters, like the inclination, i and the position angle of
the line of nodes (PA_lon) of the disk of the Large Magellanic Cloud (LMC) are
estimated using the JH photometric data of red clump stars from the Infrared
Survey Facility - Magellanic Cloud Point Source Catalog (IRSF-MCPSC). The
observed LMC region is divided into several sub-regions and stars in each
region are cross identified with the optically identified red clump stars to
obtain the near infrared magnitudes. The peak values of H magnitude and (J-H)
colour of the observed red clump distribution are obtained by fitting a profile
to the distributions and also by taking the average value of magnitude and
colour of the red clump stars in the bin with largest number. Then the
dereddened peak H0 magnitude of the red clump stars in each sub-region is
obtained. The RA, Dec and relative distance from the center of each sub-region
are converted into x, y & z Cartesian coordinates. A weighted least square
plane fitting method is applied to this x,y,z data to estimate the structural
parameters of the LMC disk. A reddening map based on (J-H) colour of the RC
stars is presented. When the peaks of the red clump distribution were
identified by averaging, an inclination of 25.7 +/- 1.6 and PA_lon = 141.5 +/-
4.5 were obtained. We estimate a distance modulus of 18.47 +/- 0.1 mag to the
LMC. Extra-planar features which are in front as well as behind the fitted
plane are identified which match with the optically identified extra-planar
features. The bar of the LMC is found to be part of the disk within 500 pc. The
estimates of the structural parameters are found to be independent of the
photometric bands used for the analysis. We find that the inner disk, within
3.0, is less inclined and has larger value of PA_lon when compared to the outer
disk.


title: Anisotropic hydrodynamics -- basic concepts

abstract:
  Due to the rapid longitudinal expansion of the quark-gluon plasma created in
relativistic heavy ion collisions, potentially large local rest frame
momentum-space anisotropies are generated. The magnitude of these
momentum-space anisotropies can be so large as to violate the central
assumption of canonical viscous hydrodynamical treatments which linearize
around an isotropic background. In order to better describe the early-time
dynamics of the quark gluon plasma, one can consider instead expanding around a
locally anisotropic background which results in a dynamical framework called
anisotropic hydrodynamics. In this proceedings contribution we review the basic
concepts of the anisotropic hydrodynamics framework presenting viewpoints from
both the phenomenological and microscopic points of view.


abstract:
  The irrotational motion of a compressible inviscid fluid is studied in the
field of analogue gravity, where its metric is compared to that in general
relativity, a fluid analogue of an evaporating black hole has been realized
experimentally, and there are symmetries related to the standard model. Here we
show the analogy also extends quantitatively to electromagnetic and quantum
mechanical phenomena. We discuss a candidate model to account for the number
and precision of these analogies.


title:
Sp(2,$\mathbb{Z}$) invariant Wigner function on even dimensional vector
  space

abstract:
  We construct the quasi probability distribution $W(p,q)$ on even dimensional
vector space with marginality and invariance under the transformation induced
by projective representation of the group ${\rm Sp}(2,\mathbb{Z})$ whose
elements correspond to linear canonical transformation.
  On even dimensional vector space, non-existence of such a quasi probability
distribution whose arguments take physical values was shown in our previous
paper(Phys.Rev.A{\bf 65} 032105(2002)). For this reason we study a quasi
probability distribution $W(p,q)$ whose arguments $q$ and $p$ take not only $N$
physical values but also $N$ unphysical values, where $N$ is dimension of
vector space. It is shown that there are two quasi probability distributions on
even dimensional vector space. The one is equivalent to the Wigner function
proposed by Leonhardt, and the other is a new one.


title:
An Analysis on Minimum s-t Cut Capacity of Random Graphs with Specified
  Degree Distribution

abstract:
  The capacity (or maximum flow) of an unicast network is known to be equal to
the minimum s-t cut capacity due to the max-flow min-cut theorem. If the
topology of a network (or link capacities) is dynamically changing or unknown,
it is not so trivial to predict statistical properties on the maximum flow of
the network. In this paper, we present a probabilistic analysis for evaluating
the accumulate distribution of the minimum s-t cut capacity on random graphs.
The graph ensemble treated in this paper consists of weighted graphs with
arbitrary specified degree distribution. The main contribution of our work is a
lower bound for the accumulate distribution of the minimum s-t cut capacity.
From some computer experiments, it is observed that the lower bound derived
here reflects the actual statistical behavior of the minimum s-t cut capacity
of random graphs with specified degrees.


title: On the Cancellation Mechanism of Radiation from the Unruh detector

abstract:
  A uniformly accelerated detector (Unruh detector) in the Minkowski vacuum is
excited as if it is exposed to the thermal bath with temperature proportional
to its acceleration. In the inertial frame, since both of an excitation and a
deexcitation of the detector are accompanied by emission of radiation into the
Minkowski vacuum, one may suspect that the Unruh detector emits radiation like
the Larmor radiation from an accelerated charged particle. However, it is known
that the radiation is miraculously cancelled by a quantum interference effect.
In this paper, we investigate under what condition the radiation cancels out.
We first show that the cancellation occurs if the Green function satisfies a
relation similar to the Kubo-Martin-Schwinger (KMS) condition. We then study
two examples, Unruh detectors in the 3+1 dimensional Minkowski spacetime and in
the de Sitter spacetime. In both cases, the relation holds only in a restricted
region of the spacetime, but the radiation is cancelled in the whole spacetime.
Hence the KMS-like relation is necessary but not sufficient for the
cancellation to occur.


title: The random graph

abstract:
  Erd\H{o}s and R\'{e}nyi showed the paradoxical result that there is a unique
(and highly symmetric) countably infinite random graph. This graph, and its
automorphism group, form the subject of the present survey.


title:
A testable prediction of the no-signalling condition using a variant of
  the EPR-Bohm example

abstract:
  Predictive power of the no-signalling condition (NSC) is demonstrated in a
testable situation involving a non-ideal Stern-Gerlach (SG) device in one of
the two wings of the EPR-Bohm entangled pairs. In this wing, for two types of
measurement in the other wing, we consider the spin state of a selected set of
particles that are confined to a particular half of the plane while emerging
from the SG magnetic field region. Due to non-idealness of the SG setup, this
spin state will have superposing components involving a relative phase for
which a testable quantitative constraint is obtained by invoking NSC, thereby
providing a means for precision testing of this fundamentally significant
principle.


title:
One-particle irreducible functional approach - a new route to
  diagrammatic extensions of DMFT

abstract:
  We present an approach which is based on the one-particle irreducible (1PI)
generating functional formalism and includes electronic correlations on all
length-scales beyond the local correlations of dynamical mean field theory
(DMFT). This formalism allows us to unify aspects of the dynamical vertex
approximation (D\GammaA) and the dual fermion (DF) scheme, yielding a
consistent formulation of non-local correlations at the one- and two-particle
level beyond DMFT within the functional integral formalism. In particular, the
considered approach includes one-particle reducible contributions from the
three- and more-particle vertices in the dual fermion approach, as well as some
diagrams not included in the ladder version of D\GammaA. To demonstrate the
applicability and physical content of the 1PI approach, we compare the
diagrammatics of 1PI, DF and D\GammaA, as well as the numerical results of
these approaches for the half-filled Hubbard model in two dimensions.


title:
Glasses of dynamically asymmetric binary colloidal mixtures: Quiescent
  properties and dynamics under shear

abstract:
  We investigate mixing effects on the glass state of binary colloidal
hard-sphere-like mixtures with large size asymmetry, at a constant volume
fraction phi = 0.61. The structure, dynamics and viscoelastic response as a
function of mixing ratio reflect a transition between caging by one or the
other component. The strongest effect of mixing is observed in systems
dominated by caging of the large component. The possibility to pack a large
number of small spheres in the free volume left by the large ones induces a
pronounced deformation of the cage of the large spheres, which become
increasingly delocalised. This results in faster dynamics and a strong
reduction of the elastic modulus. When the relative volume fraction of small
spheres exceeds that of large spheres, the small particles start to form their
own cages, slowing down the dynamics and increasing the elastic modulus of the
system. The large spheres become the minority and act as an impurity in the
ordering beyond the first neighbour shell, i.e. the cage, and do not directly
affect the particle organisation on the cage level. In such a system, when
shear at constant rate is applied, melting of the glass is observed due to
facilitated out-of-cage diffusion which is associated with structural
anisotropy induced by shear.


title: D-term Triggered Dynamical Supersymmetry Breaking

abstract:
  We present the mechanism of the dynamical supersymmetry breaking at the
metastable vacuum recently uncovered in the N=1 U(N) supersymmetric gauge
theory that contains adjoint superfields and that is specified by Kahler and
non-canonical gauge kinetic functions and a superpotential whose tree vacua
preserve N=1 supersymmetry. The overall U(1) serves as the hidden sector and no
messenger superfield is required. The dynamical supersymmetry breaking is
triggered by the non-vanishing D term coupled to the observable sector, and is
realized by the self-consistent Hartree-Fock approximation of the NJL type
while it eventually brings us the non-vanishing F term as well. It is shown
that theoretical analysis is resolved as a variational problem of the effective
potential for three kinds of background fields, namely, the complex scalar, and
the two order parameters D and F of supersymmetry, the last one being treated
perturbatively. We determine the stationary point and numerically check the
consistency of such treatment as well as the local stability of the scalar
potential. The coupling to the N = 1 supergravity is given and the gravitino
mass formula is derived.


title:
Matrix-Product Ansatz for Excited States of Fractional Quantum Hall
  Systems

abstract:
  Recently, it was discussed that the $\nu=1/3$ fractional quantum Hall state
can be expressed by a one-dimensional lattice model with an exact matrix-prduct
ground state, when toroidal boundary conditions are assumed for a narrow strip
[Phys. Rev. Lett. {\bf 109} (2012) 016401]. In this article, we discuss how the
excitation spectra of this system are calculated analytically based on the
matrix-product formalism. We introduce variational wave functions for various
momenta and optimize them. The obtained spectra of the charge neutral
excitations show the magneto-roton behavior.


title:
Overview on heavy flavour measurements in lead-lead collisions at the
  CERN-LHC

abstract:
  High energy collisions of heavy atomic nuclei allow to create and carefully
study a high-density, colour-deconfined state of strongly-interacting matter.
According to calculations from lattice Quantum-Chromodynamics, under the
conditions of high energy density and temperature reached in such collisions,
the phase transition to a quark-gluon plasma (QGP) is expected to occur, where
the colour confinement of quarks and gluons into hadrons should vanish and
chiral symmetry should be restored. Heavy-flavour particles, containing charm
and beauty, are unique probes of the conditions of the medium formed in
nucleus-nucleus collisions at high energy. In this report recent measurements
on open and hidden heavy-flavour production in lead-lead collisions at CERN's
Large Hadron Collider are presented and discussed.


title:
Quantum measurements and maps preserving strict convex combinations and
  pure states

abstract:
  In this paper, a characterization of maps between quantum states that
preserve pure states and strict convex combinations is obtained. Based on this
characterization, a structural theorem for maps between multipartite quantum
states that preserve separable pure states and strict convex combinations is
established. Then these results are applied to characterize injective (local)
quantum measurements and answer some conjectures proposed in
[J.Phys.A:Math.Theor. 45 (2012) 205305].


title: Distribution of $r_{12} \cdot p_{12}$ in quantum systems

abstract:
  We introduce the two-particle probability density $X(x)$ of
$x=\bm{r}_{12}\cdot\bm{p}_{12}=\left(\bm{r}_1-\bm{r}_2\right) \cdot
\left(\bm{p}_1-\bm{p}_2\right)$. We show how to derive $X(x)$, which we call
the Posmom intracule, from the many-particle wavefunction. We contrast it with
the Dot intracule [Y. A. Bernard, D. L. Crittenden, P. M. W. Gill, Phys. Chem.
Chem. Phys., 10, 3447 (2008)] which can be derived from the Wigner distribution
and show the relationships between the Posmom intracule and the one-particle
Posmom density [Y. A. Bernard, D. L. Crittenden, P. M. W .Gill, J.Phys. Chem.A,
114, 11984 (2010)]. To illustrate the usefulness of $X(x)$, we construct and
discuss it for a number of two-electron systems.


title: Lie ring isomorphisms between nest algebras on Banach spaces

abstract:
  Let ${\mathcal N}$ and ${\mathcal M}$ be nests on Banach spaces $X$ and $Y$
over the (real or complex) field $\mathbb F$ and let $\mbox{\rm Alg}{\mathcal
N}$ and $\mbox{\rm Alg}{\mathcal M}$ be the associated nest algebras,
respectively. It is shown that a map $\Phi:{\rm Alg}{\mathcal N}\rightarrow{\rm
Alg}{\mathcal M}$ is a Lie ring isomorphism (i.e., $\Phi$ is additive, Lie
multiplicative and bijective) if and only if $\Phi$ has the form $\Phi(A) =
TAT^{-1} + h(A)I$ for all $A\in \mbox{\rm Alg}{\mathcal N}$ or
$\Phi(A)=-TA^*T^{-1}+h(A)I$ for all $A\in \mbox{\rm Alg}{\mathcal N}$, where
$h$ is an additive functional vanishing on all commutators and $T$ is an
invertible bounded linear or conjugate linear operator when $\dim X=\infty$;
$T$ is a bijective $\tau$-linear transformation for some field automorphism
$\tau$ of $\mathbb F$ when $\dim X<\infty$.


title:
Composite representations of new SUSY algebra under nonlinear SUSY
  transformations in curved spacetime

abstract:
  We discuss composite representations of new supersymmetry (SUSY) algebra
under nonlinear (NL) SUSY transformations in curved space-time from the
viewpoint of nonlinear supersymmetric general relativity (NLSUSY GR)/ SGM
scenario. We show in the linearization of NLSUSY how various basic fields in
linear SUSY theories/supergravity are expressed as functionals in terms of a
vierbein and Nambu-Goldstone fermion fundamental fields in NLSUSY GR.


title: Constraints on dark photons from $\pi^0$ decays

abstract:
  Several models of dark matter suggest the existence of hidden sectors
consisting of SU(3)_C x SU(2)_L x U(1)_Y singlet fields. The interaction
between the ordinary and hidden sectors could be transmitted by new Abelian
U'(1) gauge bosons A' (dark or hidden photons) mixing with ordinary photons. If
such A's have masses below the \pi^0 meson mass, they would be produced through
\gamma - A' mixing in the \pi^0 ->2\gamma - decays and be observed via their
decays A' -> e+e- in a detector. Using bounds from the SINDRUM experiment at
the Paul Scherrer Institute that searched for an excess of e+e- pairs in \pi^-
p interactions at rest, the area excluding the \gamma - A' mixing \epsilon >
10^{-3} for the A' mass region 25 < M_{A'} < 120 MeV is derived.


title:
Chaotic dynamics in three dimensions: a topological proof for a triopoly
  game model

abstract:
  We rigorously prove the existence of chaotic dynamics for the triopoly game
model already studied, mainly from a numerical viewpoint, in the working paper
by Naimzada and Tramontana [2011]. In the model considered, the three firms are
heterogeneous and in fact each of them adopts a different decisional mechanism,
i.e., linear approximation, best response and gradient mechanisms,
respectively. The method we employ is the so-called "Stretching Along the
Paths" (SAP) technique in Pireddu and Zanolin [2007], based on the
Poincar\'e-Miranda Theorem and on the properties of the cutting surfaces.


title:
Determination of SU(2) ChPT LECs from 2+1 flavor staggered lattice
  simulations

abstract:
  By fitting pion masses and decay constants from 2+1 flavor staggered lattice
simulations to the predictions of NLO and NNLO SU(2) chiral perturbation theory
we determine the low-energy constants l_3 and l_4. The lattice ensembles were
generated by the Wuppertal-Budapest collaboration and cover pion masses in the
range of 135 to 435 MeV and lattice scales between 0.7 and 2.0 GeV. By choosing
a suitable scaling trajectory, we were able to demonstrate that precise and
stable results for the LECs can be obtained from continuum ChPT to NLO. The
pion masses available in this work also allow us to study the applicability of
using ChPT to extrapolate from higher masses to the physical pion mass.


title: Optimality of a class of entanglement witnesses for $3\otimes 3$ systems

abstract:
  Let $\Phi_{t,\pi}: M_3({\mathbb C}) \rightarrow M_3({\mathbb C})$ be a linear
map defined by
$\Phi_{t,\pi}(A)=(3-t)\sum_{i=1}^3E_{ii}AE_{ii}+t\sum_{i=1}^3E_{i,\pi(i)}AE_{i,\pi(i)}^\dag-A$,
where $0\leq t\leq 3$ and $\pi$ is a permutation of $(1,2,3)$. We show that the
Hermitian matrix $W_{\Phi_{t,\pi}}$ induced by $\Phi_{t,\pi}$ is an optimal
entanglement witness if and only if $t=1$ and $\pi$ is cyclic.


title:
Electric-field switching magnetization and spin transfer in ultrathin
  BiFeO3 film

abstract:
  First-principles density-functional theory calculations show switching
magnetization by 90 degree can be achieved in ultrathin BFO film by applying
external electric-field. Up-spin carriers appear to the surface with positive
field while down-spin ones to the negative field surface, arising from the
redistribution of Fe-t2g orbital. The half-metallic behavior of Fe-3d states in
the surface of R phase film makes it a promising candidate for AFM/FM bilayer
heterostructure possessing electric-field tunable FM magnetization reversal and
opens a new way towards designing spintronic multiferroics. The interface
exchange-bias effect in this BFO/FM bilayer is mainly driven by the Fe-t2g
orbital reconstruction, as well as spin transferring and rearrangement.


title: Circular orbits in the extreme Reissner-Nordstr{\o}m dihole metric

abstract:
  We study the motion of neutral test particles in the gravitational field of
two charged black holes described by the extreme Reissner-Nordstr{\o}m dihole
metric where the masses and charges of the black holes are chosen such that the
gravitational attraction is compensated by the electrostatic repulsion. We
investigate circular orbits in the equatorial plane between the two black holes
with equal masses as well as the case of circular orbits outside this symmetry
plane. We show that the first case reduces to an effective two-body problem
with a behavior similar to a system described by the Reissner-Nordstr{\o}m
spacetime. The main focus is directed to the second case with circular orbits
outside the equatorial plane.


title: Spin-rotation coupling in compound spin objects

abstract:
  We generalize spin-rotation coupling to compound spin systems. In the case of
muons bound to nuclei in a storage ring the decay process acquires a
modulation. Typical frequencies for $Z/A\sim 1/2$ are $\sim 3\times 10^6$Hz, a
factor 10 higher than the modulation observed in $g-2$ experiments.


title: Active Gel Model of Amoeboid Cell Motility

abstract:
  We develop a model of amoeboid cell motility based on active gel theory.
Modeling the motile apparatus of a eukaryotic cell as a confined layer of
finite length of poroelastic active gel permeated by a solvent, we first show
that, due to active stress and gel turnover, an initially static and
homogeneous layer can undergo a contractile-type instability to a polarized
moving state in which the rear is enriched in gel polymer. This agrees
qualitatively with motile cells containing an actomyosin-rich uropod at their
rear. We find that the gel layer settles into a steadily moving, inhomogeneous
state at long times, sustained by a balance between contractility and filament
turnover. In addition, our model predicts an optimal value of the
gel-susbstrate adhesion leading to maximum layer speed, in agreement with cell
motility assays. The model may be relevant to motility of cells translocating
in complex, confining environments that can be mimicked experimentally by cell
migration through microchannels.


title: Mean-field analysis of the q-voter model on networks

abstract:
  We present a detailed investigation of the behavior of the nonlinear q-voter
model for opinion dynamics. At the mean-field level we derive analytically, for
any value of the number q of agents involved in the elementary update, the
phase diagram, the exit probability and the consensus time at the transition
point. The mean-field formalism is extended to the case that the interaction
pattern is given by generic heterogeneous networks. We finally discuss the case
of random regular networks and compare analytical results with simulations.


title: Multiset Codes for Permutation Channels

abstract:
  This paper introduces the notion of multiset codes as relevant to the problem
of reliable information transmission over permutation channels. The motivation
for studying permutation channels comes from the effect of out of order
delivery of packets in some types of packet networks. The proposed codes are a
generalization of the so-called subset codes, recently proposed by the authors.
Some of the basic properties of multiset codes are established, among which
their equivalence to integer codes under the Manhattan metric. The presented
coding-theoretic framework follows closely the one proposed by Koetter and
Kschischang for the operator channels. The two mathematical models are similar
in many respects, and the basic idea is presented in a way which admits a
unified view on coding for these types of channels.


title: A Note On Edge Connectivity and Parity Factor

abstract:
  In this paper, we investigate some parity factors by using Lov\'asz's
(g,f)-parity theorem. Let $m>0$ be an integer. Firstly, we obtain a sufficient
and necessary condition for some graphs to have a parity factor with restricted
minimum degree. Secondly, we obtain some sufficient conditions for a graph to
have a parity factor with minimum degree $m$ in term of edge connectivity.


title:
On the Capacity of Special Classes of Gaussian Relay Networks with
  Orthogonal Components and Noncausal State Information at Source

abstract:
  In this paper, we study relay networks with orthogonal components in presence
of noncausal channel state information (CSI) available at the source. We
propose an upper bound on the capacity of the discrete memoryless model (DM)for
the case in which just the source component intended for the destination is
encoded against the CSI known non-causally at the source. Also, we derive
capacity for two special classes of the Gaussian structure of the model. The
first class is the one for which we have obtained the upper bound and the
second class is the one in which all of the source components intended for the
relays and destination are encoded against the noncausal CSI, however, no
interference at the relays and destination exists in this case.


title:
Consistent nonparametric Bayesian inference for discretely observed
  scalar diffusions

abstract:
  We study Bayes procedures for the problem of nonparametric drift estimation
for one-dimensional, ergodic diffusion models from discrete-time, low-frequency
data. We give conditions for posterior consistency and verify these conditions
for concrete priors, including priors based on wavelet expansions.


title: On geodesics of phyllotaxis

abstract:
  Seeds of sunflowers are often modelled by the map $n\longmapsto
\varphi_\theta(n)=\sqrt{n}e^{2i\pi n\theta}$ leading to a roughly uniform
repartition with two consecutive seeds separated by the divergence angle
$2\pi\theta$ for $\theta$ the golden ratio. We associate to an arbitrary real
divergence angle $2\pi \theta$ a geodesic path $\gamma_\theta: \mathbb
R_{>0}\longrightarrow \mathrm{PSL}_2(\mathbb Z)\backslash \mathbb H$ of the
modular curve and use it for local descriptions of the image
$\varphi_\theta(\mathbb N)$ of the phyllotactic map $\varphi_\theta$.


title:
Determining the implied volatility in the Dupire equation for vanilla
  European call options

abstract:
  The Black-Scholes model gives vanilla Europen call option prices as a
function of the volatility. We prove Lipschitz stability in the inverse problem
of determining the implied volatility, which is a function of the underlying
asset, from a collection of quoted option prices with different strikes.


title: A semi-Lagrangian scheme for the game $p$-Laplacian via $p$-averaging

abstract:
  We present and analyze an approximation scheme for the two-dimensional game
$p$-Laplacian in the framework of viscosity solutions. The approximation is
based on a semi-Lagrangian scheme which exploits the idea of $p$-averages. We
study the properties of the scheme and prove that it converges, in particular
cases, to the viscosity solution of the game $p$-Laplacian. We also present a
numerical implementation of the scheme for different values of $p$; the
numerical tests show that the scheme is accurate.


title: Fick's Second Law Transformed: One Path to Cloaking in Mass Diffusion

abstract:
  Here, we adapt the concept of transformational thermodynamics, whereby the
flux of temperature is controlled via anisotropic heterogeneous diffusivity,
for the diffusion and transport of mass concentration. The n-dimensional,
time-dependent, anisotropic heterogeneous Fick's equation is considered, which
is a parabolic partial differential equation also applicable to heat diffusion,
when convection occurs, for example in fluids. This theory is illustrated with
finite element computations for a liposome particle surrounded by a cylindrical
multilayered cloak in a water-based environment, and for a spherical
multilayered cloak consisting of layers of fluid with an isotropic homogeneous
diffusivity, deduced from an effective medium approach. Initial potential
applications could be sought in bio-engineering.


title: Measurements of deep inelastic scattering at HERA

abstract:
  After fifteen years of running and a further five years of analysis, the
final inclusive deep inelastic scattering cross sections from H1 and ZEUS have
been published. Measurements of neutral current and charged current processes
in ep collisions at HERA are presented. These provide us with the most valuable
information on the structure of the proton, which tells us about the
fundamental structure of matter and is essential for understanding processes at
proton colliders such as the Large Hadron Collider. The measurements also
demonstrate the chiral structure of the weak force and give a beautiful
demonstration of the unification of the electromagnetic and weak forces. The
new data will be presented in detail and comparisons with the latest
predictions of the Standard Model shown. The H1 and ZEUS collaborations have
also performed fits of the parton distribution functions in the proton; the
results of these fits will also be presented.


title: Chiral Tunnelling in Twisted Graphene Bilayer

abstract:
  The perfect transmission in graphene monolayer and the perfect reflection in
Bernal graphene bilayer for electrons incident in the normal direction of a
potential barrier are viewed as two incarnations of the Klein paradox. Here we
show a new and unique incarnation of the Klein paradox. Owing to the different
chiralities of the quasiparticles involved, the chiral fermions in twisted
graphene bilayer shows adjustable probability of chiral tunnelling for normal
incidence: they can be changed from perfect tunnelling to partial/perfect
reflection, or vice versa, by controlling either the height of the barrier or
the incident energy. As well as addressing basic physics about how the chiral
fermions with different chiralities tunnel through a barrier, our results
provide a facile route to tune the electronic properties of the twisted
graphene bilayer.


title: Supergiant Fast X-ray Transients: a review

abstract:
  Supergiant Fast X-ray Transients are a class of Galactic High Mass X-ray
Binaries with supergiant companions. Their extreme transient X-ray flaring
activity was unveiled thanks to INTEGRAL/IBIS observations. The SFXTs dynamic
range, with X-ray luminosities from 1E32 erg/s to 1E37 erg/s, and long time
intervals of low X-ray emission, are puzzling, given that both their donor star
properties and their orbital and spin periodicities seem very similar to those
displayed by massive binaries with persistent X-ray emission. Clumpy supergiant
winds, accretion barriers, orbital geometries and wind anisotropies are often
invoked to explain their behavior, but still several open issues remain. A
review of the main recent observational results will be outlined, together with
a summary of the new scenarios proposed to explain their bright flaring X-ray
activity. The main result of a long Suzaku observation of the SFXT
IGRJ16479-4514 with the shortest orbital period is also briefly summarized. The
observation of the X-ray eclipse in this source allowed us to directly probe
the supergiant wind density at the orbital separation, leading to the
conclusion that it is too large to justify the low X-ray luminosity. A
mechanism reducing the accretion rate onto the compact object is required.


title: Cooperative Fluorescence from a Strongly Driven Dilute Cloud of Atoms

abstract:
  We investigate cooperative fluorescence in a dilute cloud of strongly driven
two-level emitters. Starting from the Heisenberg equations of motion, we
compute the first-order scattering corrections to the saturation of the
excited-state population and to the resonance-fluorescence spectrum, which both
require going beyond the state-of-the-art linear-optics approach to describe
collective phenomena. A dipole blockade is observed due to long range
dipole-dipole coupling that vanishes at stronger driving fields. Furthermore,
we compute the inelastic component of the light scattered by a cloud of many
atoms and find that the Mollow triplet is affected by cooperativity. In a lobe
around the forward direction, the inelastic Mollow triplet develops a spectral
asymmetry, observable under experimental conditions.


title:
Spin-dependent gradient correction for more accurate atomization
  energies of molecules

abstract:
  We discuss, simplify, and improve the spin-dependent correction of L.A.
Constantin et al., Phys. Rev. B 84, 233103, for atomization energies, and
develop a density parameter of the form $v\propto |\nabla n|/n^{10/9}$, found
from the statistical ensemble of one-electron densities. The here constructed
exchange-correlation generalized gradient approximations (GGAs), named zvPBEsol
and zvPBEint, show a broad applicability, and a good accuracy for many
applications, because these corrected functionals significantly improve the
atomization and binding energies of molecular systems, without worsening the
behavior of the original functionals (PBEsol and PBEint) for other properties.
This spin-dependent correction is also applied to meta-GGA dynamical
correlation functionals combined with exact-exchange; in this case a
significant (about 30%) improvement in atomization energies of small molecules
is found.


title: Renormalization of gauge theories without cohomology

abstract:
  We investigate the renormalization of gauge theories without assuming
cohomological properties. We define a renormalization algorithm that preserves
the Batalin-Vilkovisky master equation at each step and automatically extends
the classical action till it contains sufficiently many independent parameters
to reabsorb all divergences into parameter-redefinitions and canonical
transformations. The construction is then generalized to the master functional
and the field-covariant proper formalism for gauge theories. Our results hold
in all manifestly anomaly-free gauge theories, power-counting renormalizable or
not. The extension algorithm allows us to solve a quadratic problem, such as
finding a sufficiently general solution of the master equation, even when it is
not possible to reduce it to a linear (cohomological) problem.


title: Determinism without causality

abstract:
  Causality has been often confused with the notion of determinism. It is
mandatory to separate the two notions in view of the debate about quantum
foundations. Quantum theory provides an example of causal not-deterministic
theory. Here we introduce a toy operational theory that is deterministic and
non-causal, thus proving that the two notions of causality and determinism are
totally independent.


title:
Peptide pores in lipid bilayers : voltage facilitation pleads for a
  revised model

abstract:
  We address the problem of antimicrobial peptides that create pores in lipid
bilayers, focusing on voltage-temperature dependence of pore opening. Two novel
experiments (voltage-clamp with alamethicin as an emblematic representative of
these peptides and neutron reflectivity of lipid-monolayer at solid/water
interface under electric field) serve to revise the only current theoretical
model (H. W. Huang et al.Phys. Rev. Lett., 92, 198304 (2004)). We introduce a
general contribution of the electric field as being responsible for an
unbalanced tension of the two bilayer leaflets and we claim that the main
entropy cost of one pore opening is due to the corresponding "excluded-area"
for lipid translation.


title: On coherent structure in wall turbulence

abstract:
  A new theory of coherent structure in wall turbulence is presented.
  The theory is the first to predict packets of hairpin vortices and other
structure in turbulence, and their dynamics, based on an analysis of the
Navier-Stokes equations, under an assumption of a turbulent mean profile. The
assumption of the turbulent mean acts as a restriction on the class of possible
structures. It is shown that the coherent structure is a manifestation of
essentially low-dimensional flow dynamics, arising from a critical layer
mechanism. Using the decomposition presented in McKeon & Sharma (J. Fluid Mech,
658, 2010), complex coherent structure is recreated from minimal superpositions
of response modes predicted by the analysis, which take the form of
radially-varying travelling waves. By way of example, simple combinations of
these modes are offered that predicts hairpins and modulated hairpin packets.
  The phase interaction also predicts important skewness and correlation
results known in the literature.
  It is also shown that the very large scale motions act to organise
hairpin-like structures such that they co-locate with areas of low streamwise
momentum, by a mechanism of locally varying the shear profile.
  The relationship between Taylor's hypothesis and coherence is discussed and
both are shown to be the consequence of the localisation of the response modes
around the critical layer.
  A pleasing link is made to the classical laminar inviscid theory, whereby the
essential mechanism underlying the hairpin vortex is captured by two obliquely
interacting Kelvin-Stuart (cat's eye) vortices. Evidence for the theory is
presented based on comparison to observations of structure reported in the
experimental, transitional flow and turbulent flow numerical simulation
literature.


title:
Ultraviolet divergences in the cyclic Wilson loop and their
  renormalization

abstract:
  We discuss the cyclic Wilson loop, i.e. a rectangular Wilson loop that spans
the entire compactified time axis in the imaginary time formalism. The result
of a perturbative calculation at $O(\alpha_s^2)$ is given, with the main focus
on the ultraviolet divergences of this operator. Based on a general analysis of
divergences in loop diagrams, we find that, unlike usual Wilson loops, the
cyclic loop does not have cusp divergences but intersection divergences, where
the intersections arise due to the periodic boundary conditions. As a result,
the cyclic Wilson loop itself is not multiplicatively renormalizable, but the
difference between it and the correlator of two Polyakov loops is.


title:
Random laser from engineered nanostructures obtained by surface tension
  driven lithography

abstract:
  The random laser emission from the functionalized thienyl-S,S-dioxide
quinquethiophene (T5OCx) in confined patterns with different shapes is
demonstrated. Functional patterning of the light emitter organic material in
well defined features is obtained by spontaneous molecular self-assembly guided
by surface tension driven (STD) lithography. Such controlled supramolecular
nano-aggregates act as scattering centers allowing the fabrication of
one-component organic lasers with no external resonator and with desired shape
and efficiency. Atomic force microscopy shows that different geometric pattern
with different supramolecular organization obtained by the lithographic process
tailors the coherent emission properties by controlling the distribution and
the size of the random scatterers.


title: Conformal methods for massless Feynman integrals and large N_f methods

abstract:
  We review the large N method of calculating high order information on the
renormalization group functions in a quantum field theory which is based on
conformal integration methods. As an example these techniques are applied to a
typical graph contributing to the beta-function of O(N) phi^4 theory at
O(1/N^2). The possible future directions for the large N methods are discussed
in light of the development of more recent techniques such as the Laporta
algorithm.


title: LHC constraints on M_1/2 and m_0 in the semi-constrained NMSSM

abstract:
  Constraints from searches for squarks and gluinos at the LHC at sqrt{s}=8 TeV
are applied to the parameter space of the NMSSM with universal squark/slepton
and gaugino masses at the GUT scale, but allowing for non-universal soft Higgs
mass parameters (the sNMSSM). We confine ourselves to regions of the parameter
space compatible with a 125 GeV Higgs boson with diphoton signal rates at least
as large as the Standard Model ones, and a dark matter candidate compatible
with WMAP and XENON100 constraints. Following the simulation of numerous points
in the m_0-M_{1/2} plane, we compare the constraints on the sNMSSM from 3-5
jets + missing E_T channels as well as from multijet + missing E_T channels
with the corresponding cMSSM constraints. Due to the longer squark decay
cascades, lower bounds on M_{1/2} are alleviated by up to 50 GeV. For heavy
squarks at large m_0, the dominant constraints originate from multijet +
missing E_T channels due to gluino decays via stop pairs.


title:
Origin of electronic Raman scattering and the Fano resonance in metallic
  carbon nanotubes

abstract:
  Fano resonance spectra for the G band in metallic carbon nanotubes are
calculated as a function of laser excitation energy in which the origin of the
resonance is given by an interference between the continuous electronic Raman
spectra and the discrete phonon spectra. We found that the second-order
scattering process of the non-zero q electron-electron interaction is more
relevant to the continuous spectra rather than the q = 0 first-order process
because the q = 0 direct Coulomb interaction vanishes due to the symmetry of
the two sublattices of a nanotube. We also show that the RBM spectra of
metallic carbon nanotubes have an asymmetric line shape which previously had
been overlooked.


title:
Ionisation in atmospheres of Brown Dwarfs and extrasolar planets III.
  Breakdown conditions for mineral clouds

abstract:
  Electric discharges were detected directly in the cloudy atmospheres of
Earth, Jupiter and Saturn, are debatable for Venus, and indirectly inferred for
Neptune and Uranus in our solar system. Sprites (and other types of transient
luminous events) have been detected only on Earth, and are theoretically
predicted for Jupiter, Saturn and Venus. Cloud formation is a common phenomenon
in ultra-cool atmospheres such as in Brown Dwarf and extrasolar planetary
atmospheres. Cloud particles can be expected to carry considerable charges
which may trigger discharge events via small-scale processes between individual
cloud particles (intra-cloud discharges) or large-scale processes between
clouds (inter-cloud discharges). We investigate electrostatic breakdown
characteristics, like critical field strengths and critical charge densities
per surface, to demonstrate under which conditions mineral clouds undergo
electric discharge events which may trigger or be responsible for sporadic
X-ray emission. We apply results from our kinetic dust cloud formation model
that is part of the Drift-Phoenix model atmosphere simulations. We present a
first investigation of the dependence of the breakdown conditions in Brown
Dwarf and giant gas exoplanets on the local gas-phase chemistry, the effective
temperature and primordial gas-phase metallicity. Our results suggest that
different intra-cloud discharge processes dominate at different heights inside
mineral clouds: local coronal (point discharges) and small-scale sparks at the
bottom region of the cloud where the gas density is high, and flow discharges
and large-scale sparks near, and maybe above, the cloud top. The comparison of
the thermal degree of ionisation and the number density of cloud particles
allows us to suggest the efficiency with which discharges will occur in
planetary atmospheres.


title:
Microscopic Description of Nuclear Fission: Fission Barrier Heights of
  Even-Even Actinides

abstract:
  We evaluate the performance of modern nuclear energy density functionals for
predicting inner and outer fission barrier heights and energies of fission
isomers of even-even actinides. For isomer energies and outer barrier heights,
we find that the self-consistent theory at the HFB level is capable of
providing quantitative agreement with empirical data.


title:
Zero-lag synchronization in coupled time-delayed piecewise linear
  electronic circuits

abstract:
  We investigate and report an experimental confirmation of zero-lag
synchronization (ZLS) in a system of three coupled time-delayed piecewise
linear electronic circuits via dynamical relaying with different coupling
configurations, namely mutual and subsystem coupling configurations. We have
observed that when there is a feedback between the central unit (relay unit)
and at least one of the outer units, ZLS occurs in the two outer units whereas
the central and outer units exhibit inverse phase synchronization (IPS). We
find that in the case of mutual coupling configuration ZLS occurs both in
periodic and hyperchaotic regimes, while in the subsystem coupling
configuration it occurs only in the hyperchaotic regime. Snapshots of the time
evolution of outer circuits as observed from the oscilloscope confirm the
occurrence of ZLS experimentally. The quality of ZLS is numerically verified by
correlation coefficient and similarity function measures. Further, the
transition to ZLS is verified from the changes in the largest Lyapunov
exponents and the correlation coefficient as a function of the coupling
strength. IPS is experimentally confirmed using time series plots and also can
be visualized using the concept of localized sets which are also corroborated
by numerical simulations. In addition, we have calculated the correlation of
probability of recurrence to quantify the phase coherence. We have also
analytically derived a sufficient condition for the stability of ZLS using the
Krasovskii-Lyapunov theory.


title: Asymptotics of a vanishing period : characterization of semi-simplicity

abstract:
  In this paper we introduce the word {\em fresco} to denote a monogenic
geometric (a,b)-module. This "basic object" (generalized Brieskorn module with
one generator) corresponds to the formal germ of the minimal filtered (regular)
differential equation. Such an equation is satisfied by a relative de Rham
cohomology class at a critical value of a holomorphic function on a smooth
complex manifold. In [B.09] the first structure theorems are proved. Then in
[B.10] we introduced the notion of {\em theme} which corresponds in the \
$[\lambda]-$primitive case to frescos having a unique Jordan-H{\"o}lder
sequence (a unique Jordan block for the monodromy). Themes correspond to
asymptotic expansion of a given vanishing period, so to an image of a fresco in
the module of asymptotic expansions. For a fixed relative de Rham cohomology
class (for instance given by a smooth differential form $d-$closed and
$df-$closed) each choice of a vanishing cycle in the spectral eigenspace of the
monodromy for the eigenvalue \ $exp(2i\pi.\lambda)$ \ produces a \
$[\lambda]-$primitive theme, which is a quotient of the fresco associated to
the given relative de Rham class itself. \\ We show that for any fresco there
exists an {\em unique} Jordan-H{\"o}lder sequence, called the {\em principal
J-H. sequence}, with corresponding quotients giving the opposite of the roots
of the Bernstein polynomial in increasing order. We study the semi-simple part
of a given fresco and we characterize the semi-simplicity of a fresco by the
fact for any given order on the roots of its Bernstein polynomial we may find a
J-H. sequence making them appear with this order. Then we construct a numerical
invariant, called the \ $\beta-$invariant, and we show that it produces
numerical criteria in order to give a necessary and sufficient condition on a
fresco to be semi-simple. We show that these numerical invariants define a
natural algebraic stratification on the set of isomorphism classes of fresco
with given fundamental invariants (or equivalently with given roots of the
Bernstein polynomial).


title:
Global generalized synchronization in networks of different time-delay
  systems

abstract:
  We show that global generalized synchronization (GS) exists in structurally
different time-delay systems, even with different orders, with quite different
fractal (Kaplan-Yorke) dimensions, which emerges via partial GS in
symmetrically coupled regular networks. We find that there exists a smooth
transformation in such systems, which maps them to a common GS manifold as
corroborated by their maximal transverse Lyapunov exponent. In addition, an
analytical stability condition using the Krasvoskii-Lyapunov theory is deduced.
This phenomenon of GS in strongly distinct systems opens a new way for an
effective control of pathological synchronous activity by means of extremely
small perturbations to appropriate variables in the synchronization manifold.


title:
Implications for electron acceleration and transport from non-thermal
  electron rates at looptop and footpoint sources in solar flares

abstract:
  The interrelation of hard X-ray (HXR) emitting sources and the underlying
physics of electron acceleration and transport presents one of the major
questions in high-energy solar flare physics. Spatially resolved observations
of solar flares often demonstrate the presence of well-separated sources of
bremsstrahlung emission, so-called coronal and footpoint sources. Using
spatially resolved X-ray observations by the Reuven Ramaty High Energy Solar
Spectroscopic Imager (RHESSI) and recently improved imaging techniques, we
investigate in detail the spatially resolved electron distributions in a few
well-observed solar flares. The selected flares can be interpreted as having a
standard geometry with chromospheric HXR footpoint sources related to
thick-target X-ray emission and the coronal sources characterised by a
combination of thermal and thin-target bremsstrahlung. Using imaging
spectroscopy techniques, we deduce the characteristic electron rates and
spectral indices required to explain the coronal and footpoint X-ray sources.
We found that, during the impulsive phase, the electron rate at the looptop is
several times (a factor of 1.7-8) higher than at the footpoints. The results
suggest that a sufficient number of electrons accelerated in the looptop
explain the precipitation into the footpoints and imply that electrons
accumulate in the looptop. We discuss these results in terms of magnetic
trapping, pitch-angle scattering, and injection properties. Our conclusion is
that the accelerated electrons must be subject to magnetic trapping and/or
pitch-angle scattering, keeping a fraction of the population trapped inside the
coronal loops. These findings put strong constraints on the particle transport
in the coronal source and provide quantitative limits on deka-keV electron
trapping/scattering in the coronal source.


title: Paradoxes in Social Networks with Multiple Products

abstract:
  Recently, we introduced in arXiv:1105.2434 a model for product adoption in
social networks with multiple products, where the agents, influenced by their
neighbours, can adopt one out of several alternatives. We identify and analyze
here four types of paradoxes that can arise in these networks. To this end, we
use social network games that we recently introduced in arxiv:1202.2209. These
paradoxes shed light on possible inefficiencies arising when one modifies the
sets of products available to the agents forming a social network. One of the
paradoxes corresponds to the well-known Braess paradox in congestion games and
shows that by adding more choices to a node, the network may end up in a
situation that is worse for everybody. We exhibit a dual version of this, where
removing available choices from someone can eventually make everybody better
off. The other paradoxes that we identify show that by adding or removing a
product from the choice set of some node may lead to permanent instability.
Finally, we also identify conditions under which some of these paradoxes cannot
arise.


title:
Testing the OPE Wilson coefficient for $A^2$ from lattice QCD with a
  dynamical charm

abstract:
  Gluon and ghost propagators data, obtained in Landau gauge from lattice
simulations with two light and two heavy dynamical quark flavours
($N_f$=2+1+1), are described here with a running formula including a four-loop
perturbative expression and a nonperturbative OPE correction dominated by the
local operator $A^2$. The Wilson coefficients and their variation as a function
of the coupling constant are extracted from the numerical data and compared
with the theoretical expressions that, after being properly renormalized, are
known at ${\cal O}(\alpha^4)$. As also $\Lambda_{\msbar}$ is rather well known
for $N_f$=2+1+1, this allows for a precise consistency test of the OPE approach
in the joint description of different observables.


title:
Intermittent stick-slip dynamics during the peeling of an adhesive tape
  from a roller

abstract:
  We study experimentally the fracture dynamics during the peeling at a
constant velocity of a roller adhesive tape mounted on a freely rotating
pulley. Thanks to a high speed camera, we measure, in an intermediate range of
peeling velocities, high frequency oscillations between phases of slow and
rapid propagation of the peeling fracture. This so-called stick-slip regime is
well known as the consequence of a decreasing fracture energy of the adhesive
in a certain range of peeling velocity coupled to the elasticity of the peeled
tape. Simultaneously with stick-slip, we observe low frequency oscillations of
the adhesive roller angular velocity which are the consequence of a pendular
instability of the roller submitted to the peeling force. The stick-slip
dynamics is shown to become intermittent due to these slow pendular
oscillations which produce a quasi-static oscillation of the peeling angle
while keeping constant the peeling fracture velocity (averaged over each
stick-slip cycle). The observed correlation between the mean peeling angle and
the stick-slip amplitude questions the validity of the usually admitted
independence with the peeling angle of the fracture energy of adhesives.


title:
Stationary Bound States of Dirac Particles in the Schwarzschild
  Gravitational Field

abstract:
  Nondecaying bound states of elementary spin-half particles are validated and
calculated numerically for the Schwarzschild gravitational field using a
self-conjugate Hamiltonian with a flat scalar product for any value of the
gravitational coupling constant. Hilbert condition g_{00}>0 leads to a boundary
condition such that components of the vector of current density of Dirac
particles are zero near the "event horizon". At small values of the coupling
constant, the energy spectrum is close to the hydrogen-like spectrum. Based on
the results of this study, we can assume that there exists a new type of
collapsars, for which the Hawking radiation mechanism is not present. From the
standpoint of cosmology, if the value of the gravitational coupling constant is
small, alpha<<1, the new type of nonradiating relict collapsars can manifest
itself only through gravitation. Thus, they are good candidates for the role of
"dark matter" carriers. In the wide range of admissible masses, there can exist
collapsars of a new type with the masses of hypothesized WIMP particles, which
are treated as representatives of "dark matter" in numerous scenarios of the
expansion of the universe. The results of this study can lead to revisiting
some concepts of the standard cosmological model related to the evolution of
the universe and interaction of collapsars with surrounding matter.


title:
Adaptive propagation of quantum few-body systems with time-dependent
  Hamiltonians

abstract:
  In this study, a variety of methods are tested and compared for the numerical
solution of the Schr\"odinger equation for few-body systems with explicitely
time-dependent Hamiltonians, with the aim to find the optimal one. The
configuration interaction method, generally applied to find stationary
eigenstates accurately and without approximations to the wavefunction's
structure, may also be used for the time-evolution, which results in a large
linear system of ordinary differential equations. The large basis sizes
typically present when the configuration interaction method is used calls for
efficient methods for the time evolution. Apart from efficiency, adaptivity (in
the time domain) is the other main focus in this study, such that the time step
is adjusted automatically given some requested accuracy. A method is suggested
here, based on an exponential integrator approach, combined with different ways
to implement the adaptivity, which was found to be faster than a broad variety
of other methods that were also considered.


title: The Third Proof of Lov\'asz's Cathedral Theorem

abstract:
  A graph $G$ with a perfect matching is called saturated if $G+e$ has more
perfect matchings than $G$ for any edge $e$ that is not in $G$. Lov\'asz gave a
characterization of the saturated graphs called the cathedral theorem, with
some applications to the enumeration problem of perfect matchings, and later
Szigeti gave another proof. In this paper, we give a new proof with our
preceding works which revealed canonical structures of general graphs with
perfect matchings. Here, the cathedral theorem is derived in quite a natural
way, providing more refined or generalized properties. Moreover, the new proof
shows that it can be proved without using the Gallai-Edmonds structure theorem.


title:
Low velocity shocks: signatures of turbulent dissipation in diffuse
  irradiated gas

abstract:
  We examine the chemical and emission properties of mildly irradiated (G0=1)
magnetised shocks in diffuse media (nH=10^2 to 10^4 /cm3) at low to moderate
velocities (from 3 to 40 km/s). Results: The formation of some molecules relies
on endoergic reactions. In J-shocks, their abundances are enhanced by several
orders of magnitude for shock velocities as low as 7 km/s. Otherwise most
chemical properties of J-type shocks vary over less than an order of magnitude
between velocities from about 7 to about 30 km/s, where H2 dissociation sets
in. C-type shocks display a more gradual molecular enhancement as the shock
velocity increases. We quantify the energy flux budget (fluxes of kinetic,
radiated and magnetic energies) with emphasis on the main cooling lines of the
cold interstellar medium. Their sensitivity to shock velocity is such that it
allows observations to constrain statistical distributions of shock velocities.
We fit various probability distribution functions (PDFs) of shock velocities to
spectroscopic observations of the galaxy-wide shock in Stephan's Quintet (SQ)
and of a Galactic line of sight sampling diffuse molecular gas in Chamaeleon.
In both cases, low velocities bear the greatest statistical weight and the PDF
is consistent with a bimodal distribution. In the very low velocity shocks
(below 5 km/s), dissipation is due to ion-neutral friction which powers H2 low
energy transitions and atomic lines. In moderate velocity shocks (20 km/s and
above), the dissipation is due to viscous heating and accounts for most of the
molecular emission. In our interpretation a significant fraction of the gas on
the line of sight is shocked (from 4% to 66%). For example, C+ emission may
trace shocks in UV irradiated gas where C+ is the dominant carbon species.


title:
Absence of the non-uniqueness problem of the Dirac theory in a curved
  spacetime. Spin-rotation coupling is not physically relevant

abstract:
  As opposed to Arminjon statements, in this work we again assert the absence
of the non-uniqueness problem of the Dirac theory in a curved and flat
spacetime and illustrate this with a number of examples. Dirac Hamiltonians in
arbitrary, including time-dependent, gravitational fields uniquely determine
physical characteristics of quantum-mechanical systems irrespective of the
choice of the tetrad fields. Direct spin-rotation coupling that occurs with a
certain choice of tetrads does not manifest itself in final physical
characteristics of the systems and therefore does not represent a physically
relevant effect.


title: Monogamy deficit for quantum correlation in multipartite quantum system

abstract:
  We introduce the concept of monogamy deficit for quantum correlation by
combining together two types of monogamy inequalities depending on different
measurement sides. For tripartite pure state, we demonstrate a relation which
connects two types of monogamy inequalities for quantum discord and provide the
difference between them. By using this relation, we obtain an unified physical
interpretation for these two monogamy deficit. In addition, we find an
interesting fact that there is a general monogamy condition for several quantum
correlations for tripartite pure states. We then provide a necessary and
sufficient condition for the establishment of one kind of monogamy inequality
for tripartite mixed state and generalize it to multipartite quantum state.


title:
On the number of real eigenvalues of products of random matrices and an
  application to quantum entanglement

abstract:
  The probability that there are $k$ real eigenvalues for an $n$ dimensional
real random matrix is known. Here we study this for the case of products of
independent random matrices. Relating the problem of the probability that the
product of two real 2 dimensional random matrices has real eigenvalues to an
issue of optimal quantum entanglement, this is fully analytically solved. It is
shown that in $\pi/4$ fraction of such products the eigenvalues are real. Being
greater than the corresponding known probability ($1/\sqrt{2}$) for a single
matrix, it is shown numerically that the probability that {\it all} eigenvalues
of a product of random matrices are real tends to unity as the number of
matrices in the product increases indefinitely. Some other numerical
explorations, including the expected number of real eigenvalues is also
presented, where an exponential approach of the expected number to the
dimension of the matrix seems to hold.

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


title: Exact algorithms for dominating induced matchings

abstract:
  Say that an edge of a graph G dominates itself and every other edge adjacent
to it. An edge dominating set of a graph G = (V,E) is a subset of edges E' of E
which dominates all edges of G. In particular, if every edge of G is dominated
by exactly one edge of E' then E' is a dominating induced matching. It is known
that not every graph admits a dominating induced matching, while the problem to
decide if it does admit is NP-complete. In this paper we consider the problem
of finding a minimum weighted dominating induced matching, if any, of a graph
with weighted edges. We describe two exact algorithms for general graphs. The
algorithms are efficient in the cases where G admits a known vertex dominating
set of small size, or when G contains a polynomial number of maximal
independent sets.


title: On quasi modules at infinity for vertex algebras

abstract:
  A theory of quasi modules at infinity for (weak) quantum vertex algebras
including vertex algebras was previously developed in \cite{li-infinity}. In
this current paper, quasi modules at infinity for vertex algebras are
revisited. Among the main results, we extend some technical results, to fill in
a gap in the proof of a theorem therein, and we obtain a commutator formula for
general quasi modules at infinity and establish a version of the converse of
the aforementioned theorem.


title: Particles accelerate the detachment of viscous liquids

abstract:
  During detachment of a viscous fluid extruded from a nozzle a filament
linking the droplet to the latter is formed. Under the effect of surface
tension the filament thins until pinch off and final detachment of the droplet.
In this paper we study the effect of the presence of individual particles
trapped in the filament on the detachment dynamics using granular suspensions
of small volume fractions ({\phi} < 6%). We show that even a single particle
strongly modifies the detachment dynamics. The particle perturbs the thinning
of the thread and a large droplet of fluid around the particle is formed. This
perturbation leads to an acceleration of the detachment of the droplet compared
to the detachment ob- served for a pure fluid. We quantify this acceleration
for single particles of different sizes and link it to similar ob- servations
for suspensions of small volume fractions. Our study also gives more insight
into particulate effects on de- tachment of more dense suspensions and allows
to explain the accelerated detachment close to final pinch off observed
previously (Bonnoit et al 2012)


title:
Burgeoning the Higgs mass to 125 GeV through messenger-matter
  interactions in GMSB models

abstract:
  A 125 GeV Higgs renders the simpler GMSB models unnatural, essentially
pushing the soft spectrum beyond the LHC reach. A direct coupling of the matter
and messenger fields, that facilitates an enhanced mixing in the squark sector,
is a way to ameliorate this deficiency. We construct all possible
messenger-matter interaction terms considering the messenger multiplets in 1, 5
and 10 dimensional representations of the SU(5). A Froggatt-Nielsen like flavor
framework connected with the origin of fermion mass hierarchy is utilized to
control the interaction terms and suppress FCNC. We perform a detailed
comparative study of the efficiency of such interaction terms to boost the
Higgs mass keeping the soft spectrum light. We identify the more promising
models and comment on their status in present and future collider studies.


title:
Waiting times for particles in a branching Brownian motion to reach the
  rightmost position

abstract:
  It has been proved by Lalley and Sellke [13] that every particle born in a
branching Brownian motion has a descendant reaching the rightmost position at
some future time. The main goal of the present paper is to estimate
asymptotically as s goes to infinity, the first time that every particle alive
at the time s has a descendant reaching the rightmost position.


title: Yielding of binary colloidal glasses

abstract:
  The rheological response, in particular the non-linear response, to
oscillatory shear is experimentally investigated in colloidal glasses. The
glasses are highly concentrated binary hard-sphere mixtures with relatively
large size disparities. For a size ratio of 0.2, a strong reduction of the
normalized elastic moduli, the yield strain and stress and, for some samples,
even melting of the glass to a fluid is observed upon addition of the second
species. This is attributed to the more efficient packing, as indicated by the
shift of random close packing to larger total volume fractions. This leads to
an increase in free volume which favours cage deformations and hence a
loosening of the cage. Cage deformations are also favoured by the structural
heterogeneity introduced by the second species. For a limited parameter range,
we furthermore found indications of two-step yielding, as has been reported
previously for attractive glasses. In samples containing spheres with more
comparable sizes, namely a size ratio of 0.38, the cage seems less distorted
and structural heterogeneities on larger length scales seem to become
important. The limited structural changes are reflected in only a small
reduction of the moduli, yield strain and stress.


title: Chimera States in Mechanical Oscillator Networks

abstract:
  The synchronization of coupled oscillators is a fascinating manifestation of
self-organization that nature employs to orchestrate essential processes of
life, such as the beating of the heart. Although it was long thought that
synchrony or disorder were mutually exclusive steady states for a network of
identical oscillators, numerous theoretical studies in recent years have
revealed the intriguing possibility of `chimera states', in which the symmetry
of the oscillator population is broken into a synchronous and an asynchronous
part. However, a striking lack of empirical evidence raises the question of
whether chimeras are indeed characteristic to natural systems. This calls for a
palpable realization of chimera states without any fine-tuning, from which
physical mechanisms underlying their emergence can be uncovered. Here, we
devise a simple experiment with mechanical oscillators coupled in a
hierarchical network to show that chimeras emerge naturally from a competition
between two antagonistic synchronization patterns. We identify a wide spectrum
of complex states, encompassing and extending the set of previously described
chimeras. Our mathematical model shows that the self-organization observed in
our experiments is controlled by elementary dynamical equations from mechanics
that are ubiquitous in many natural and technological systems. The symmetry
breaking mechanism revealed by our experiments may thus be prevalent in systems
exhibiting collective behaviour, such as power grids, opto-mechanical crystals
or cells communicating via quorum sensing in microbial populations.

categories: nlin.AO cond-mat.stat-mech nlin.PS physics.class-ph


title:
Relative locality and relative Co-locality as extensions of the
  Generalized Uncertainty Principle

abstract:
  I introduce the spatial curvature effects inside the formalism of Relative
Locality as a non-commutative structure of the momentum space in agreement with
the very well known concepts of Quantum Groups. This gives a natural red-shift
effect in agreement with an extended version of the Generalized Uncertainty
Principle (GUP) and in agreement with the standard notions of curvature inside
General Relativity. I then introduce the concept of Relative Co-locality as a
reinterpretation of the usual notions of spacetime curvature. From this
redefinition, I obtain the momentum space curvature effects as a
non-commutativity in position space. This introduce a natural blue-shift effect
in agreement with the extended version of GUP. Both effects, Relative locality
and Co-locality are dual each other inside the formalism of quantum groups
$SU_q(n)$ symmetric Heisenberg algebras and their q-Bargmann Fock
representations. When Relative locality and Co-locality are introduced, the
q-deformation parameter takes the form $q\approx 1+\sqrt{\frac{\vert p\vert
\vert x\vert}{r_\Lambda m_{pl}}}$ with the spatial curvature effects in
Relative Locality appearing like $\Delta X\approx \frac{\vert
x\vert}{m_{pl}}\Delta P$ and the momentum curvature effects in Relative
Co-locality appearing like $\Delta P\approx \frac{\vert
p\vert}{r_\Lambda}\Delta X$, where $r_\Lambda=\frac{1}{\sqrt{\Lambda}}$ is the
scale defined by the Cosmological Constant $\Lambda$, $m_{pl}$ is the Planck
mass and $\Delta X/\Delta P$ is a scale of position/momentum or time/energy
associated with the event, p and x are the momentum and position of the
observer relative to the event.


title: Dynamical kurtosis of net and total proton distributions in STAR at RHIC

abstract:
  We report the energy and centrality dependence of dynamical kurtosis for Au +
Au collisions at $\sqrt{s_{NN}}$ = 7.7, 11.5, 19.6, 27, 39, 62.4 and 200 GeV at
RHIC. The dynamical kurtosis of net-proton is compared to that of total-proton.
The results are also compared with AMPT model calculations.


title:
Dual origin of defect magnetism in graphene and its reversible switching
  by molecular doping

abstract:
  A possibility to control magnetic properties by using electric fields is one
of the most desirable characteristics for spintronics applications. Finding a
suitable material remains an elusive goal, with only a few candidates found so
far. Graphene is one of them and offers a hope due to its weak spin-orbit
interaction, the ability to control electronic properties by the electric field
effect and the possibility to introduce paramagnetic centres such as vacancies
and adatoms. Here we show that adatoms magnetism in graphene is itinerant and
can be controlled by doping, so that magnetic moments can be switched on and
off. The much-discussed vacancy magnetism is found to have a dual origin, with
two approximately equal contributions: one coming from the same itinerant
magnetism and the other due to broken bonds. Our work suggests that magnetic
response of graphene can be controlled by the field effect, similar to its
transport and optical properties, and that spin diffusion length can be
significantly enhanced above a certain carrier density.


title:
Non-exponential spontaneous emission dynamics for emitters in a
  time-dependent optical cavity

abstract:
  We have theoretically studied the effect of deterministic temporal control of
spontaneous emission in a dynamic optical microcavity. We propose a new
paradigm in light emission: we envision an ensemble of two-level emitters in an
environment where the local density of optical states is modified on a time
scale shorter than the decay time. A rate equation model is developed for the
excited state population of two-level emitters in a time-dependent environment
in the weak coupling regime in quantum electrodynamics. As a realistic
experimental system, we consider emitters in a semiconductor microcavity that
is switched by free-carrier excitation. We demonstrate that a short temporal
increase of the radiative decay rate depletes the excited state and drastically
increases the emission intensity during the switch time. The resulting
time-dependent spontaneous emission shows a distribution of photon arrival
times that strongly deviates from the usual exponential decay: A deterministic
burst of photons is spontaneously emitted during the switch event.


title:
Quantifying the behaviour of curvature perturbations near Horizon
  Crossing

abstract:
  How much does the curvature perturbation change after it leaves the horizon,
and when should one evaluate the power spectrum? To answer these questions we
study single field inflation models numerically, and compare the evolution of
different curvature perturbations from horizon crossing to the end of
inflation. We find that e.g. in chaotic inflation, the amplitude of the
comoving and the curvature perturbation on uniform density hypersurfaces differ
by up to 180 \% at horizon crossing assuming the same amplitude at the end of
inflation, and that it takes approximately 3 efolds for the curvature
perturbation to be within 1 \% of its value at the end of inflation.


title: The strong Lefschetz property in codimension two

abstract:
  Every artinian quotient of $K[x,y]$ has the strong Lefschetz property if $K$
is a field of characteristic zero or is an infinite field whose characteristic
is greater than the regularity of the quotient. We improve this bound in the
case of monomial ideals. Using this we classify when both bounds are sharp.
Moreover, we prove that the artinian quotient of a monomial ideal in $K[x,y]$
always has the strong Lefschetz property, regardless of the characteristic of
the field, exactly when the ideal is lexsegment. As a consequence we describe a
family of non-monomial complete intersections that always have the strong
Lefschetz property.


title: Discovery of the spectroscopic binary nature of six southern Cepheids

abstract:
  We present the analysis of photometric and spectroscopic data of six bright
Galactic Cepheids: GH Carinae, V419 Centauri, V898 Centauri, AD Puppis, AY
Sagittarii, and ST Velorum. Based on new radial velocity data (in some cases
supplemented with earlier data available in the literature), these Cepheids
have been found to be members in spectroscopic binary systems. V898 Cen turned
out to have one of the largest orbital radial velocity amplitude (> 40 km/s)
among the known binary Cepheids. The data are insufficient to determine the
orbital periods nor other orbital elements for these new spectroscopic
binaries.
  These discoveries corroborate the statement on the high frequency of
occurrence of binaries among the classical Cepheids, a fact to be taken into
account when calibrating the period-luminosity relationship for Cepheids.
  We have also compiled all available photometric data that revealed that the
pulsation period of AD Pup, the longest period Cepheid in this sample, is
continuously increasing with Delta P = 0.004567 d/century, likely to be caused
by stellar evolution. The wave-like pattern superimposed on the parabolic O-C
graph of AD Pup may well be caused by the light-time effect in the binary
system. ST Vel also pulsates with a continuously increasing period. The other
four Cepheids are characterised with stable pulsation periods in the last half
century.


title: Topology of character varieties of Abelian groups

abstract:
  Let G be a complex reductive algebraic group (not necessarily connected), let
K be a maximal compact subgroup, and let A be a finitely generated Abelian
group. We prove that the conjugation orbit space Hom(A,K)/K is a strong
deformation retract of the GIT quotient space Hom(A,G)//G. As a corollary, we
determine necessary and sufficient conditions for the character variety
Hom(A,G)//G to be irreducible when G is connected and semisimple. For a general
connected reductive G, analogous conditions are found to be sufficient for
irreducibility, when A is free abelian.


title:
Optimisation of out-vessel magnetic diagnostics for plasma boundary
  reconstruction in tokamaks

abstract:
  To improve the low frequency spectrum of magnetic field measurements of
future tokamak reactors such as ITER, several steady state magnetic sensor
technologies have been considered. For all the studied technologies it is
always advantageous to place the sensors outside the vacuum vessel and as far
away from the reactor core to minimize radiation damage and temperature
effects, but not so far as to compromise the accuracy of the equilibrium
reconstruction. We have studied to what extent increasing the distance between
out-vessel sensors and plasma can be compensated for sensor accuracy and/or
density before the limit imposed by the degeneracy of the problem is reached.
The study is particularized for the Swiss TCV tokamak, due to the quality of
its magnetic data and its ability to operate with a wide range of plasma shapes
and divertor configurations. We have scanned the plasma boundary reconstruction
error as function of out-vessel sensor density, accuracy and distance to the
plasma. The study is performed for both the transient and steady state phases
of the tokamak discharge. We find that, in general, there is a broad region in
the parameter space where sensor accuracy, density and proximity to the plasma
can be traded for one another to obtain a desired level of accuracy in the
reconstructed boundary, up to some limit. Extrapolation of the results to a
tokamak reactor suggests that a hybrid configuration with sensors inside and
outside the vacuum vessel could be used to obtain a good boundary
reconstruction during both the transient and the flat-top of the discharges, if
out-vessel magnetic sensors of sufficient density and accuracy can be placed
sufficiently far outside the vessel to minimize radiation damage.


title:
NaviCell: a web-based environment for navigation, curation and
  maintenance of large molecular interaction maps

abstract:
  Molecular biology knowledge can be systematically represented in a
computer-readable form as a comprehensive map of molecular interactions. There
exist a number of maps of molecular interactions containing detailed
description of various cell mechanisms. It is difficult to explore these large
maps, to comment their content and to maintain them. Though there exist several
tools addressing these problems individually, the scientific community still
lacks an environment that combines these three capabilities together. NaviCell
is a web-based environment for exploiting large maps of molecular interactions,
created in CellDesigner, allowing their easy exploration, curation and
maintenance. NaviCell combines three features: (1) efficient map browsing based
on Google Maps engine; (2) semantic zooming for viewing different levels of
details or of abstraction of the map and (3) integrated web-based blog for
collecting the community feedback. NaviCell can be easily used by experts in
the field of molecular biology for studying molecular entities of their
interest in the context of signaling pathways and cross-talks between pathways
within a global signaling network. NaviCell allows both exploration of detailed
molecular mechanisms represented on the map and a more abstract view of the map
up to a top-level modular representation. NaviCell facilitates curation,
maintenance and updating the comprehensive maps of molecular interactions in an
interactive fashion due to an imbedded blogging system. NaviCell provides an
easy way to explore large-scale maps of molecular interactions, thanks to the
Google Maps and WordPress interfaces, already familiar to many users. Semantic
zooming used for navigating geographical maps is adopted for molecular maps in
NaviCell, making any level of visualization meaningful to the user. In
addition, NaviCell provides a framework for community-based map curation.


title:
Rank regularization and Bayesian inference for tensor completion and
  extrapolation

abstract:
  A novel regularizer of the PARAFAC decomposition factors capturing the
tensor's rank is proposed in this paper, as the key enabler for completion of
three-way data arrays with missing entries. Set in a Bayesian framework, the
tensor completion method incorporates prior information to enhance its
smoothing and prediction capabilities. This probabilistic approach can
naturally accommodate general models for the data distribution, lending itself
to various fitting criteria that yield optimum estimates in the
maximum-a-posteriori sense. In particular, two algorithms are devised for
Gaussian- and Poisson-distributed data, that minimize the rank-regularized
least-squares error and Kullback-Leibler divergence, respectively. The proposed
technique is able to recover the "ground-truth'' tensor rank when tested on
synthetic data, and to complete brain imaging and yeast gene expression
datasets with 50% and 15% of missing entries respectively, resulting in
recovery errors at -10dB and -15dB.


title:
Order estimation of the best approximations and of the approximations by
  Fourier sums of classes of $(\psi,\beta)$--diferentiable functions

abstract:
  There were established the exact-order estimations of the best uniform
approximations by{\psi} the trigonometrical polynoms on the
$C^{\psi}_{\beta,p}$ classes of $2\pi$-periodic continuous functions $f$, which
are defined by the convolutions of the functions, which belong to the unit ball
in $L_p$, $1\leq p <\infty$ spaces with generating fixed kernels
$\Psi_{\beta}\subset|L_{p'}$, $\frac{1}{p}+\frac{1}{p'}=1$, whose Fourier
coeficients decreasing to zero approximately as power functions. The exact
order estimations were also established in $L_p$-metrics, $1 < p \leq\infty$
for $L^{\psi}_{\beta,1}$ classes of $2\pi$-periodic functions $f$, which are
equivalent by means of Lebesque measure to the convolutions of
$\Psi_{\beta}\subset|L_{p}$ kernels with the functions that belong to the unit
ball in $L_1$ space. We showed that in investigating cases the orders of best
approximations are realized by Fourier sums.


title:
Wake monochromator in asymmetric and symmetric Bragg and Laue geometry
  for self-seeding the European X-ray FEL

abstract:
  We discuss the use of self-seeding schemes with wake monochromators to
produce TW power, fully coherent pulses for applications at the dedicated
bio-imaging bealine at the European X-ray FEL, a concept for an upgrade of the
facility beyond the baseline previously proposed by the authors. We exploit the
asymmetric and symmetric Bragg and Laue reflections (sigma polarization) in
diamond crystal. Optimization of the bio-imaging beamline is performed with
extensive start-to-end simulations, which also take into account effects such
as the spatio-temporal coupling caused by the wake monochromator. The spatial
shift is maximal in the range for small Bragg angles. A geometry with Bragg
angles close to pi/2 would be a more advantageous option from this viewpoint,
albeit with decrease of the spectral tunability. We show that it will be
possible to cover the photon energy range from 3 keV to 13 keV by using four
different planes of the same crystal with one rotational degree of freedom.


title: The p-adic group ring of SL_2(p^f)

abstract:
  In this article we show that the $\Z_p[\zeta_{p^f-1}]$-order
$\Z_p[\zeta_{p^f-1}]\SL_2(p^f)$ can be recognized among those orders whose
reduction modulo $p$ is isomorphic to $\F_{p^f}\SL_2(p^f)$ using only
ring-theoretic properties (in other words we show that $\F_{p^f}\SL_2(p^f)$
lifts uniquely to a $\Z_p[\zeta_{p^f-1}]$-order, provided certain reasonable
conditions are imposed on the lift). This proves a conjecture made by Nebe
concerning the basic order of $\Z_p[\zeta_{p^f-1}]\SL_2(p^f)$.


title:
A new limit on the CP violating decay KS -> 3pi0 with the KLOE
  experiment

abstract:
  We have carried out a new direct search for the CP violating decay KS -> 3pi0
with 1.7 fb^-1 of e+e- collisions collected by the KLOE detector at the
phi-factory DAFNE. We have searched for this decay in a sample of about 5.9 x
10^8 KS KL events tagging the KS by means of the KL interaction in the
calorimeter and requiring six prompt photons. With respect to our previous
search, the analysis has been improved by increasing of a factor four the
tagged sample and by a more effective background rejection of fake KS tags and
spurious clusters. We find no candidates in data and simulated background
samples, while we expect 0.12 standard model events. Normalizing to the number
of KS -> 2pi0 events in the same sample, we set the upper limit on BR(KS ->
3pi0 < 2.6 x 10^-8 at 90% C.L., five times lower than the previous limit. We
also set the upper limit on the eta_000 parameter, |eta_000 | < 0.0088 at 90%
C.L., improving by a factor two the latest direct measurement.


title: An inequality for the entropy numbers and its application

abstract:
  We prove an inequality for the entropy numbers in terms of nonlinear
Kolmogorov's widths. This inequality is in a spirit of known inequalities of
this type and it is adjusted to the form convenient in applications for
$m$-term approximations with respect to a given system. Also, we obtain upper
bounds for the $m$-term approximation by the Weak Relaxed Greedy Algorithm with
respect to a system which is not a dictionary.


title: Improving Brownian approximations for boundary crossing problems

abstract:
  Donsker's theorem shows that random walks behave like Brownian motion in an
asymptotic sense. This result can be used to approximate expectations
associated with the time and location of a random walk when it first crosses a
nonlinear boundary. In this paper, correction terms are derived to improve the
accuracy of these approximations.


title: Hadronic and radiative decays of the tau lepton

abstract:
  This PhD thesis studies some hadronic and radiative decays of the tau lepton
using a Chiral Lagrangian including resonance fields. After a theoretical
introduction, the decays to the $(\pi \pi \pi)^-$, $(KK\pi)^-$ and
$\eta^{(\prime)} \pi^- \pi^0$ hadronic states and $\tau \to (\pi/K)^- \gamma
\nu_tau$ are analysed. Some material, which was not included in the
corresponding references, is also discussed: The structure functions analysis
for the 3 pion modes, the differential decay width as a function of the
two-particle invariant masses in the considered three-meson modes and a
simplified study of the $\tau\to$\eta^{(\prime)} \pi^- \pi^0 \nu_tau$ processes
within a single-angle mixing scheme for the $\eta$ and $\eta^\prime$ mesons.


title: Load curve data cleansing and imputation via sparsity and low rank

abstract:
  The smart grid vision is to build an intelligent power network with an
unprecedented level of situational awareness and controllability over its
services and infrastructure. This paper advocates statistical inference methods
to robustify power monitoring tasks against the outlier effects owing to faulty
readings and malicious attacks, as well as against missing data due to privacy
concerns and communication errors. In this context, a novel load cleansing and
imputation scheme is developed leveraging the low intrinsic-dimensionality of
spatiotemporal load profiles and the sparse nature of "bad data.'' A robust
estimator based on principal components pursuit (PCP) is adopted, which effects
a twofold sparsity-promoting regularization through an $\ell_1$-norm of the
outliers, and the nuclear norm of the nominal load profiles. Upon recasting the
non-separable nuclear norm into a form amenable to decentralized optimization,
a distributed (D-) PCP algorithm is developed to carry out the imputation and
cleansing tasks using networked devices comprising the so-termed advanced
metering infrastructure. If D-PCP converges and a qualification inequality is
satisfied, the novel distributed estimator provably attains the performance of
its centralized PCP counterpart, which has access to all networkwide data.
Computer simulations and tests with real load curve data corroborate the
convergence and effectiveness of the novel D-PCP algorithm.


title:
The student evaluation of teaching and the competence of students as
  evaluators

abstract:
  When the college student satisfaction survey is considered in the promotion
and recognition of instructors, a usual complaint is related to the impact that
biased ratings have on the arithmetic mean (used as a measure of teaching
effectiveness). This is especially significant when the number of students
responding to the survey is small. In this work a new methodology, considering
student to student perceptions, is presented. Two different estimators of
student rating credibility, based on centrality properties of the student
social network, are proposed. This method is established on the idea that in
the case of on-site higher education, students often know which others are
competent in rating the teaching and learning process.


title:
Spectra of radiation emitted by single-walled and multi-walled carbon
  nanotubes during multiple microwave irradiation and cooling cycles

abstract:
  Carbon nanotubes have been observed to emit ultraviolet, visible, and
infrared radiation when exposed to microwave fields. We have performed
experiments in which both single-walled (~1 nm diameters) and multi-walled
carbon nanotubes (>50 nm diameters) were exposed to 2.45 GHz microwaves during
several irradiation and cooling cycles at a pressure of ~10-6 torr. A
comparison of the spectra of the radiation emitted by the nanotubes indicates
that the intensity of radiation with wavelengths ranging from 700 to 1000 nm
increased substantially during the course of five irradiation and cooling
cycles. The data suggests that the mechanism responsible for the emissions is
field emission-induced luminescence and that the intensity of the radiation
emitted increased due to the opening of nanotube ends. Furthermore, the
intensity of the radiation emitted by the multi-walled carbon nanotubes was
much greater than the radiation emitted by the single-walled nanotubes.
Scanning electron microscopy images indicate that most of the single-walled
nanotubes were bundled together, while the multi-walled nanotubes were not.
This bundling may have resulted in a lower field enhancement factor and/or
screening effects which might help to explain the difference in the intensities
of the radiation emitted by the samples.