title: Negative refraction of inhomogeneous waves in lossy isotropic media

abstract:
  We theoretically study negative refraction of inhomogeneous waves at the
interface of lossy isotropic media. We obtain explicit (up to the sign)
expressions for the parameters of a wave transmitted through the interface
between two lossy media characterized by complex permittivity and permeability.
We show that the criterion of negative refraction that requires negative
permittivity and permeability can be used only in the case of a homogeneous
incident wave at the interface between a lossless and lossy media. In a more
general situation, when the incident wave is inhomogeneous, or both media are
lossy, the criterion of negative refraction becomes dependent on an incident
angle. Most interestingly, we show that negative refraction can be realized in
conventional lossy materials (such as metals) if their interfaces are properly
oriented.


title: Enhanced Predictive Ratio Control of Interacting Systems

abstract:
  Ratio control for two interacting processes is proposed with a PID
feedforward design based on model predictive control (MPC) scheme. At each
sampling instant, the MPC control action minimizes a state-dependent
performance index associated with a PID-type state vector, thus yielding a
PID-type control structure. Compared to the standard MPC formulations with
separated single-variable control, such a control action allows one to take
into account the non-uniformity of the two process outputs. After reformulating
the MPC control law as a PID control law, we provide conditions for prediction
horizon and weighting matrices so that the closed-loop control is
asymptotically stable, and show the effectiveness of the approach with
simulation and experiment results.


title: On the Number of Closed Factors in a Word

abstract:
  A closed word (a.k.a. periodic-like word or complete first return) is a word
whose longest border does not have internal occurrences, or, equivalently,
whose longest repeated prefix is not right special. We investigate the
structure of closed factors of words. We show that a word of length $n$
contains at least $n+1$ distinct closed factors, and characterize those words
having exactly $n+1$ closed factors. Furthermore, we show that a word of length
$n$ can contain $\Theta(n^{2})$ many distinct closed factors.


title:
Supernova remnants interacting with molecular clouds as seen with
  H.E.S.S

abstract:
  About 30 Galactic supernova remnants (SNRs) are thought to be physically
associated with molecular clouds (MCs). These systems are prime \g-ray source
candidates as the accelerated particles from shock fronts collide with the
surrounding high-density medium thus emitting gamma-rays through hadronic
interactions. However only a handful of such interacting SNRs are detected at
TeV energies. We report the current status of the High Energy Stereoscopic
System (H.E.S.S.) observations towards these SNR-MC systems, with a particular
emphasis on the latest results.


title: How well do we need to measure the Higgs boson mass and self-coupling?

abstract:
  Much of the discussion regarding future measurements of the Higgs boson mass
and self-coupling is focussed on how well various collider options can do. In
this article we ask a physics-based question of how well do we need colliders
to measure these quantities to have an impact on discovery of new physics or an
impact in how we understand the role of the Higgs boson in nature. We address
the question within the framework of the Standard Model and various beyond the
Standard Model scenarios, including supersymmetry and theories of composite
Higgs bosons. We conclude that the LHC's stated ability to measure the Higgs
boson to better than 150 MeV will be as good as we will ever need to know the
Higgs boson mass in the foreseeable future. On the other hand, we estimate that
the self-coupling will likely need to be measured to better than 20 percent to
see a deviation from the Standard Model expectation. This is a challenging
target for future collider and upgrade scenarios.


title:
Low & High scale MSSM inflation, gravitational waves and constraints
  from Planck

abstract:
  In this paper we will analyze generic predictions of an inflection-point
model of inflation with Hubble-induced corrections and study them in light of
the Planck data. Typically inflection-point models of inflation can be embedded
within Minimal Supersymmetric Standard Model (MSSM) where inflation can occur
below the Planck scale. The flexibility of the potential allows us to match the
observed amplitude of the TT-power spectrum of the cosmic microwave background
radiation with low and high multipoles, spectral tilt, and virtually mild
running of the spectral tilt, which can put a bound on an upper limit on the
tensor-to-scalar ratio, $r \leq 0.12$. Since the inflaton within MSSM carries
the Standard Model charges, therefore it is the minimal model of inflation
beyond the Standard Model which can reheat the universe with the right thermal
degrees of freedom without any dark-radiation.


title:
Pr\"ufer sheaves and generic sheaves over the weighted projective lines
  and elliptic curves

abstract:
  In the present paper, we introduce the concepts of Pr\"{u}fer sheaves and
adic sheaves over a weighted projective line of genus one or an elliptic curve,
show that Pr\"{u}fer sheaves and adic sheaves can classify the category of
coherent sheaves. Moreover, we describe the relationship between Pr\"{u}fer
sheaves and generic sheaves, and provide two methods to construct generic
sheaves by using coherent sheaves and Pr\"{u}fer sheaves.


title: Jet Quenching at LHC

abstract:
  We review up-to-date results on high-pt particles and jets in heavy ion
collisions by three major LHC experiments, ALICE, ATLAS, and CMS. Results of
analyses of 2010 and 2011 Pb+Pb data at $\sqrt{s_{NN}} = 2.76$ TeV are
discussed. We concentrate mainly on results by fully reconstructed jets and
discuss similarities and important differences in measurements among
experiments. We point to the importance of understanding the results in a view
of difference between quark-initiated and gluon-initiated jets


title: Renormalization of Composite Operators in time-dependent Backgrounds

abstract:
  We study the phenomenon of composite operator renormalization and mixing in
systems where time-translational invariance is broken and the evolution is
out-of-equilibrium. We show that composite operators mix also through non-local
memory terms which persist for periods whose duration is set by the mass scales
in the problem.


title: From Parametric Model-based Optimization to robust PID Gain Scheduling

abstract:
  In chemical process applications, model predictive control effectively deals
with input and state constraints during transient operations. However,
industrial PID controllers directly manipulates the actuators, so they play the
key role in small perturbation robustness. This paper considers the problem of
augmenting the commonplace PID with the constraint handling and optimization
functionalities of MPC. First, we review the MPC framework, which employs a
linear feedback gain in its unconstrained region. This linear gain can be any
preexisting multiloop PID design, or based on the two stabilizing PI or PID
designs for multivariable systems proposed in the paper. The resulting
controller is a feedforward PID mapping, a straightforward form without the
need of tuning PID to fit an optimal input. The parametrized solution of MPC
under constraints further leverages a familiar PID gain scheduling structure.
Steady state robustness is achieved along with the PID design so that
additional robustness analysis is avoided.


title:
Driving at the quantum speed limit: Optimal control of a two-level
  system

abstract:
  A remarkably simple result is derived for the minimal time $T_{\rm min}$
required to drive a general initial state to a final target state by a
Landau-Zener type Hamiltonian or, equivalently, by time-dependent laser
driving. The associated protocol is also derived. A surprise arises for some
states when the interaction strength is assumed to be bounded by a constant
$c$. Then, for large $c$, the optimal driving is of type bang-off-bang and for
increasing $c$ one recovers the unconstrained result. However, for smaller $c$
the optimal driving can suddenly switch to bang-bang type. We discuss the
notion of quantum speed limit time.


title: Note on $s_0$ nonmeasurable unions

abstract:
  In this note we consider an arbitrary families of sets of $s_0$ ideal
introduced by Marczewski-Szpilrajn. We show that in any uncountable Polish
space $X$ and under some combinatorial and set theoretical assumptions
($cov(s_0)=\c$ for example), that for any family $\ca\subseteq s_0$ with
$\bigcup\ca =X$, we can find a some subfamily $\ca'\subseteq\ca$ such that the
union $\bigcup\ca'$ is not $s$-measurable. We have shown a consistency of the
$cov(s_0)=\omega_1<\c$ and existence a partition of the size $\omega_1$ $\ca\in
[s_0]^{\omega}$ of the real line $\bbr$, such that there exists a subfamily
$\ca'\subseteq\ca$ for which $\bigcup\ca'$ is $s$-nonmeasurable. We also showed
that it is relatively consistent with ZFC theory that $\omega_1<\c$ and
existence of m.a.d. family $\ca$ such that $\bigcup\ca$ is $s$-nonmeasurable in
Cantor space $2^\omega$ or Baire space $\omega^\omega$. The consistency of
$a<cov(s_0)$ and $cov(s_0)<a$ is proved also.


title: Tracking Emission Rate Dynamics of NV Centers in Nanodiamonds

abstract:
  Spontaneous emission from crystal centers is influenced by both the photonic
local density of states and non-radiative processes. Here we monitor the
spontaneous emission of single nitrogen vacancy (NV) centers as their host
diamond is reduced in size from a large monolithic crystal to a nanocrystal by
successive cycles of oxidation. The size reduction induces a quenching of the
NV radiative emission. New non-radiative channels lead to a decrease of the
fluorescence intensity and the excited state lifetime. In one case we observe
the onset of blinking which may provide a route to understand these additional
non-radiative decay channels.


title:
Treatment of the infrared contribution: NLO QED evolution as a pedagogic
  example

abstract:
  We show that the conventional prescription used for DGLAP parton evolution at
NLO has an inconsistent treatment of the contribution from the infrared (IR)
region. We illustrate the problem by studying the simple example of QED
evolution, treating the electron and photon as partons. The deficiency is not
present in a physical approach which removes the IR divergency and allows
calculation in the normal 4-dimensional space.


title:
Equivariant character correspondences and inductive McKay condition for
  type A

abstract:
  As a step to establish the McKay conjecture on character degrees of finite
groups, we verify the inductive McKay condition introduced by
Isaacs-Malle-Navarro for simple groups of Lie type $A_{n-1}$, split or twisted.
Key to the proofs is the study of certain characters of SL$_n(q)$ and SU$_n(q)$
related to generalized Gelfand-Graev representations. As a by-product we can
show that a Jordan decomposition for the characters of the latter groups is
equivariant under outer automorphisms. Many ideas seem applicable to other Lie
types.


title:
When uniform weak convergence fails: Empirical processes for dependence
  functions and residuals via epi- and hypographs

abstract:
  In the past decades, weak convergence theory for stochastic processes has
become a standard tool for analyzing the asymptotic properties of various
statistics. Routinely, weak convergence is considered in the space of bounded
functions equipped with the supremum metric. However, there are cases when weak
convergence in those spaces fails to hold. Examples include empirical copula
and tail dependence processes and residual empirical processes in linear
regression models in case the underlying distributions lack a certain degree of
smoothness. To resolve the issue, a new metric for locally bounded functions is
introduced and the corresponding weak convergence theory is developed.
Convergence with respect to the new metric is related to epi- and
hypo-convergence and is weaker than uniform convergence. Still, for continuous
limits, it is equivalent to locally uniform convergence, whereas under mild
side conditions, it implies $L^p$ convergence. For the examples mentioned
above, weak convergence with respect to the new metric is established in
situations where it does not occur with respect to the supremum distance. The
results are applied to obtain asymptotic properties of resampling procedures
and goodness-of-fit tests.


title:
Pseudoprocesses related to space-fractional higher-order heat-type
  equations

abstract:
  In this paper we construct pseudo random walks (symmetric and asymmetric)
which converge in law to compositions of pseudoprocesses stopped at stable
subordinators. We find the higher-order space-fractional heat-type equations
whose fundamental solutions coincide with the law of the limiting
pseudoprocesses. The fractional equations involve either Riesz operators or
their Feller asymmetric counterparts. The main result of this paper is the
derivation of pseudoprocesses whose law is governed by heat-type equations of
real-valued order $\gamma>2$. The classical pseudoprocesses are very special
cases of those investigated here.


title: The Spectrum of an Adelic Markov Operator

abstract:
  With the help of the representation of SL(2,Z) on the rank two free module
over the integer adeles, we define the transition operator of a Markov chain.
The real component of its spectrum exhibits a gap, whereas the non-real
component forms a circle of radius 1/\sqrt{2}.


title: A remark on Li-Xu's pathology

abstract:
  For test configurations, the Donaldson-Futaki invariant F_1 is well-known. In
this note, its refinement will be discussed. Then we see that Li-Xu's pathology
doesn't occur, since their example of a non-normal test configuration, with
trivial normalization, actually has non-vanishing F_1 in this refined sense.


title: Nonlinear fluctuating hydrodynamics for anharmonic chains

abstract:
  With focus on anharmonic chains, we develop a nonlinear version of
fluctuating hydrodynamics, in which the Euler currents are kept to second order
in the deviations from equilibrium and dissipation plus noise are added. The
required model-dependent parameters are written in such a way that they can be
computed numerically within seconds, once the interaction potential, pressure,
and temperature are given. In principle the theory is applicable to any
one-dimensional system with local conservation laws. The resulting nonlinear
stochastic field theory is handled in the one-loop approximation. Some of the
large scale predictions can still be worked out analytically. For more details
one has to rely on numerical simulations of the corresponding mode-coupling
equations. In this way we arrive at detailed predictions for the equilibrium
time correlations of the locally conserved fields of an anharmonic chain.


title:
Diffraction catastrophes threaded by quantized vortex skeletons caused
  by atom-optical aberrations induced in trapped Bose-Einstein condensates

abstract:
  We propose a nonlinear atom-optics experiment to create diffraction
catastrophes threaded by quantized vortex skeletons in Bose-Einstein condensed
matter waves. We show how atom-optical aberrations induced in trapped
Bose-Einstein condensates evolve into specific caustic structures due to
imperfect focusing. Vortex skeletons, whose cross-sections are staggered vortex
lattices, are observed to nucleate inside the universal diffraction
catastrophes. Our observations shed further light on the structure and dynamics
of Bose-novae and suggest applications of matter wave diffraction catastrophes,
including detection of the order parameter pairing symmetry in cold gas
experiments.


title: Generation of hyper-entangled photon pairs in coupled microcavities

abstract:
  We propose and theoretically analyze a new scheme for generating
hyper-entangled photon pairs in a system of polaritons in coupled planar
microcavities. Starting from a microscopic model, we evaluate the relevant
parametric scattering processes and numerically simulate the phonon-induced
noise background under continuous-wave excitation. Our results show that,
compared to other polariton entanglement proposals, our scheme enables the
generation of photon pairs that are entangled in both path and polarization
degrees of freedom, and simultaneously leads to a strong reduction of the
photoluminesence noise background. This can significantly improve the fidelity
of the entangled photon pairs under realistic experimental conditions.


title: Nonlocal electrodynamics of normal and superconducting films

abstract:
  Electrically conducting films in a time-varying transverse applied magnetic
field are considered. Their behavior is strongly influenced by the self-field
of the induced currents, making the electrodynamics nonlocal, and consequently
difficult to analyze both numerically and analytically. We present a formalism
which allows many phenomena related to superconducting and Ohmic films to be
modelled and analyzed. The formalism is based on the Maxwell equations, and a
material current-voltage characteristics, linear for normal metals, and
nonlinear for superconductors, plus a careful account of the boundary
conditions. For Ohmic films, we consider the response to a delta function
source-field turned on instantly. As one of few problems in nonlocal
electrodynamics, this has an analytical solution, which we obtain, in both
Fourier and real space. Next, the dynamical behaviour of a square
superconductor film during ramping up of the field, and subsequently returning
to zero, is treated numerically. Then, this remanent state is used as initial
condition for triggering thermomagnetic avalanches. The avalanches tend to
invade the central part where the density of trapped flux is largest, forming
dendritic patterns in excellent agreement with magneto-optical images. Detailed
profiles of current and flux density are presented and discussed. Finally, the
formalism is extended to multiply connected samples, and numerical results for
a patterned superconducting film, a ring with a square lattice of antidots, are
presented and discussed.


title:
Classification of two-dimensional real evolution algebras and dynamics
  of some two-dimensional chains of evolution algebras

abstract:
  In this paper we give classification of two-dimensional real evolution
algebras. For several chains of evolution algebras we study their
classification dynamics.


title: The Gromov-Winkelmann theorem for flexible varieties

abstract:
  An affine variety $X$ of dimension $\ge 2$ is called {\em flexible} if its
special automorphism group SAut$(X)$ acts transitively on the smooth locus
$X_{reg}$ \cite{AKZ}. Recall that the special automorphism group SAut$(X)$ is
the subgroup of the automorphism group Aut$(X)$ generated by all one-parameter
unipotent subgroups \cite{AKZ}. Given a normal, flexible, affine variety $X$
and a closed subvariety $Y$ in $X$ of codimension at least 2, we show that the
pointwise stabilizer subgroup of $Y$ in the group SAut$(X)$ acts infinitely
transitively on the complement $X\backslash Y$, that is, $m$-transitively for
any $m\ge 1$. More generally we show such a result for any quasi-affine variety
$X$ and codimension $\ge 2$ subset $Y$ of $X$. In the particular case of
$X=\AA^n$, $n\ge 2$, this yields a Theorem of Gromov and Winkelmann \cite{Gr1},
\cite{Wi}.


title:
Zero-temperature Monte Carlo study of the non-coplanar phase of the
  classical bilinear-biquadratic Heisenberg model on the triangular lattice

abstract:
  We investigate the ground-state properties of the highly degenerate
non-coplanar phase of the classical bilinear-biquadratic Heisenberg model on
the triangular lattice with Monte Carlo simulations. For that purpose, we
introduce an Ising pseudospin representation of the ground states, and we use a
simple Metropolis algorithm with local updates, as well as a powerful cluster
algorithm. At sizes that can be sampled with local updates, the presence of
long-range order is surprisingly combined with an algebraic decay of
correlations and the complete disordering of the chirality. It is only thanks
to the investigation of unusually large systems (containing $\sim 10^8$ spins)
with cluster updates that the true asymptotic regime can be reached and that
the system can be proven to consist of equivalent (i.e., equally ordered)
sublattices. These large-scale simulations also demonstrate that the scalar
chirality exhibits long-range order at zero temperature, implying that the
system has to undergo a finite-temperature phase transition. Finally, we show
that the average distance in the order parameter space, which has the structure
of an infinite Cayley tree, remains remarkably small between any pair of
points, even in the limit when the real space distance between them tends to
infinity.


title:
Enhancement of graphene visibility on transparent substrates by
  refractive index optimization

abstract:
  Optical reflection microscopy is one of the main imaging tools to visualize
graphene microstructures. Here is reported a novel method that employs
refractive index optimization in an optical reflection microscope, which
greatly improves the visibility of graphene flakes. To this end, an immersion
liquid with a refractive index that is close to that of the glass support is
used in-between the microscope lens and the support improving the contrast and
resolution of the sample image. Results show that the contrast of single and
few layer graphene crystals and structures can be enhanced by a factor of 4
compared to values commonly achieved with transparent substrates using optical
reflection microscopy lacking refractive index optimization.


title: The Bishop-Phelps-Bollob\'as version of Lindenstrauss properties A and B

abstract:
  We study a Bishop-Phelps-Bollob\'as version of Lindenstrauss properties A and
B. For domain spaces, we study Banach spaces $X$ such that $(X,Y)$ has the
Bishop-Phelps-Bollob\'as property (BPBp) for every Banach space $Y$. We show
that in this case, there exists a universal function $\eta_X(\varepsilon)$ such
that for every $Y$, the pair $(X,Y)$ has the BPBp with this function. This
allows us to prove some necessary isometric conditions for $X$ to have the
property. We also prove that if $X$ has this property in every equivalent norm,
then $X$ is one-dimensional. For range spaces, we study Banach spaces $Y$ such
that $(X,Y)$ has the Bishop-Phelps-Bollob\'as property for every Banach space
$X$. In this case, we show that there is a universal function
$\eta_Y(\varepsilon)$ such that for every $X$, the pair $(X,Y)$ has the BPBp
with this function. This implies that this property of $Y$ is strictly stronger
than Lindenstrauss property B. The main tool to get these results is the study
of the Bishop-Phelps-Bollob\'as property for $c_0$-, $\ell_1$- and
$\ell_\infty$-sums of Banach spaces.


title:
The Herschel/HIFI spectral survey of OMC-2 FIR 4 (CHESS): An overview of
  the 480 to 1902 GHz range

abstract:
  Broadband spectral surveys of protostars offer a rich view of the physical,
chemical and dynamical structure and evolution of star-forming regions. The
Herschel Space Observatory opened up the terahertz regime to such surveys,
giving access to the fundamental transitions of many hydrides and to the
high-energy transitions of many other species. A comparative analysis of the
chemical inventories and physical processes and properties of protostars of
various masses and evolutionary states is the goal of the Herschel CHEmical
Surveys of Star forming regions (CHESS) key program. This paper focusses on the
intermediate-mass protostar, OMC-2 FIR 4. We obtained a spectrum of OMC-2 FIR 4
in the 480 to 1902 GHz range with the HIFI spectrometer onboard Herschel and
carried out the reduction, line identification, and a broad analysis of the
line profile components, excitation, and cooling. We detect 719 spectral lines
from 40 species and isotopologs. The line flux is dominated by CO, H2O, and
CH3OH. The line profiles are complex and vary with species and upper level
energy, but clearly contain signatures from quiescent gas, a broad component
likely due to an outflow, and a foreground cloud. We find abundant evidence for
warm, dense gas, as well as for an outflow in the field of view. Line flux
represents 2% of the 7 L_Sol luminosity detected with HIFI in the 480 to 1250
GHz range. Of the total line flux, 60% is from CO, 13% from H2O and 9% from
CH3OH. A comparison with similar HIFI spectra of other sources is set to
provide much new insight into star formation regions, a case in point being a
difference of two orders of magnitude in the relative contribution of sulphur
oxides to the line cooling of Orion KL and OMC-2 FIR 4.


title:
Differential distributions for top-quark hadro-production with a running
  mass

abstract:
  We take a look at how the differential distributions for top-quark production
are affected by changing to the running mass scheme. Specifically we consider
the transverse momentum, rapidity and pair-invariant mass distributions at NLO
for the top-quark mass in the MSbar scheme. It is found that, similar to the
total cross section, the perturbative expansion converges faster and the scale
dependence improves using the mass in the MSbar scheme as opposed to the
on-shell scheme. We also update the analysis for the total cross section using
the now available full NNLO contribution.


title:
Effect of clustering on ellipsometric spectra of randomly distributed
  gold nanoparticles on a substrate

abstract:
  We present a theoretical model for describing light scattering from randomly
distributed Au nanoparticles on a substrate, including the clustering effect.
By using the finite-element Green function method and spherical harmonic basis
functions, we are able to calculate the polarization-dependent reflectivity
spectra of the system (modeled by randomly distributed nanoparticles coupled
with clusters) efficiently and accurately. The calculated ellipsometric spectra
of the system with clusters can adequately describe the experimental data for
the whole frequency range. We find that the clustering effect leads to some
prominent features in the low frequency range of the ellipsometric spectra,
which are attributed to plasmonic resonances associated with the coupling of Au
nanoparticles and clusters.


title:
Protection of center-spin coherence by dynamically polarizing nuclear
  spin core in diamond

abstract:
  We experimentally investigate the protection of electron spin coherence of
nitrogen vacancy (NV) center in diamond by dynamical nuclear polarization. The
electron spin decoherence of an NV center is caused by the magnetic ield
fluctuation of the $^{13}$C nuclear spin bath, which contributes large thermal
fluctuation to the center electron spin when it is in equilibrium state at room
temperature. To address this issue, we continuously transfer the angular
momentum from electron spin to nuclear spins, and pump the nuclear spin bath to
a polarized state under Hartman-Hahn condition. The bath polarization effect is
verified by the observation of prolongation of the electron spin coherence time
($T_2^*$). Optimal conditions for the dynamical nuclear polarization (DNP)
process, including the pumping pulse duration and depolarization effect of
laser pulses, are studied. Our experimental results provide strong support for
quantum information processing and quantum simulation using polarized nuclear
spin bath in solid state systems.


title: Stability of persistence spaces of vector-valued continuous functions

abstract:
  Multidimensional persistence modules do not admit a concise representation
analogous to that provided by persistence diagrams for real-valued functions.
However, there is no obstruction for multidimensional persistent Betti numbers
to admit one. Therefore, it is reasonable to look for a generalization of
persistence diagrams concerning those properties that are related only to
persistent Betti numbers. In this paper, the persistence space of a
vector-valued continuous function is introduced to generalize the concept of
persistence diagram in this sense. The main result is its stability under
function perturbations: any change in vector-valued functions implies a not
greater change in the Hausdorff distance between their persistence spaces.


title:
Estimation of anthropometrical and inertial body parameters using double
  integration of residual torques and forces during squat jump

abstract:
  The inertial (IP) and anthropometrical (AP) parameters of human body are
mostly estimated from coefficients issue from cadaver measurements. These
parameters could involve errors in the calculation of joint torques during
explosive movements. The purpose of this study was to optimize the IP and AP in
order to minimize the residual torque and force during squat jumping. Three
methods of determination have been presented: method A: optimizing AP and IP of
each body part, method B: optimizing trunk AP and IP, assuming that the AP and
IP of the lower limbs were known, method C: using Winter AP and IP. For each
method, the value (degree 0), the integral (degree 1) and the double integral
(degree 2) of the residual moment were also used. The method B with degree 2
was the most accurate to determine trunk AP and IP by minimizing of the
residual force and torque, by providing a linear least squares system. Instead
of minimizing the residual force and torque, by classical way, the double
integral of the latter provided more accurate results.


title: Strong coupling of optical nanoantennas and atomic systems

abstract:
  An optical nanoantenna and adjacent atomic systems are strongly coupled when
an excitation is repeatedly exchanged between these subsystems prior to its
eventual dissipation into the environment. It remains challenging to reach the
strong coupling regime but it is equally rewarding. Once being achieved,
promising applications as signal processing at the nanoscale and at the single
photon level would immediately come into reach. Here, we study such hybrid
configuration from different perspectives. The configuration we consider
consists of two identical atomic systems, described in a two-level
approximation, which are strongly coupled to an optical nanoantenna. First, we
investigate when this hybrid system requires a fully quantum description and
provide a simple analytical criterion. Second, a design for a nanoantenna is
presented that enables the strong coupling regime. Besides a vivid time
evolution, the strong coupling is documented in experimentally accessible
quantities, such as the extinction spectra. The latter are shown to be strongly
modified if the hybrid system is weakly driven and operates in the quantum
regime. We find that the extinction spectra depend sensitively on the number of
atomic systems coupled to the nanoantenna.


title: On motivic vanishing cycles of critical loci

abstract:
  Let $U$ be a smooth scheme over an algebraically closed field $\mathbb K$ of
characteristic zero and $f:U\to{\mathbb A}^1$ a regular function, and write
$X=$Crit$(f)$, as a closed subscheme of $U$. The motivic vanishing cycle
$MF_{U,f}^\phi$ is an element of the $\hat\mu$-equivariant motivic Grothendieck
ring ${\mathcal M}^{\hat\mu}_X$ defined by Denef and Loeser math.AG/0006050 and
Looijenga math.AG/0006220, and used in Kontsevich and Soibelman's theory of
motivic Donaldson-Thomas invariants, arXiv:0811.2435.
  We prove three main results:
  (a) $MF_{U,f}^\phi$ depends only on the third-order thickenings
$U^{(3)},f^{(3)}$ of $U,f$.
  (b) If $V$ is another smooth scheme, $g:V\to{\mathbb A}^1$ is regular,
$Y=$Crit$(g)$, and $\Phi:U\to V$ is an embedding with $f=g\circ\Phi$ and
$\Phi\vert_X:X\to Y$ an isomorphism, then $\Phi\vert_X^*(MF_{V,g}^\phi)$ equals
$MF_{U,f}^\phi$ "twisted" by a motive associated to a principal ${\mathbb
Z}_2$-bundle defined using $\Phi$, where now we work in a quotient ring
$\bar{\mathcal M}^{\hat\mu}_X$ of ${\mathcal M}^{\hat\mu}_X$.
  (c) If $(X,s)$ is an "oriented algebraic d-critical locus" in the sense of
Joyce arXiv:1304.4508, there is a natural motive $MF_{X,s} \in\bar{\mathcal
M}^{\hat\mu}_X$, such that if $(X,s)$ is locally modelled on
Crit$(f:U\to{\mathbb A}^1)$, then $MF_{X,s}$ is locally modelled on
$MF_{U,f}^\phi$.
  Using results from arXiv:1305.6302, these imply the existence of natural
motives on moduli schemes of coherent sheaves on a Calabi-Yau 3-fold equipped
with "orientation data", as required in Kontsevich and Soibelman's motivic
Donaldson-Thomas theory arXiv:0811.2435, and on intersections of oriented
Lagrangians in an algebraic symplectic manifold.
  This paper is an analogue for motives of results on perverse sheaves of
vanishing cycles proved in arXiv:1211.3259. We extend this paper to Artin
stacks in arXiv:1312.0090.


title: Super-star networks: Growing optimal scale-free networks via likelihood

abstract:
  Preferential attachment --- by which new nodes attach to existing nodes with
probability proportional to the existing nodes' degree --- has become the
standard growth model for scale-free networks, where the asymptotic probability
of a node having degree $k$ is proportional to $k^{-\gamma}$. However, the
motivation for this model is entirely ad hoc. We use exact likelihood arguments
and show that the optimal way to build a scale-free network is to attach most
new links to nodes of low degree. Curiously, this leads to a scale-free
networks with a single dominant hub: a star-like structure we call a super-star
network. Asymptotically, the optimal strategy is to attach each new node to one
of the nodes of degree $k$ with probability proportional to
$\frac{1}{N+\zeta(\gamma)(k+1)^\gamma}$ (in a $N$ node network) --- a stronger
bias toward high degree nodes than exhibited by standard preferential
attachment. Our algorithm generates optimally scale-free networks (the
super-star networks) as well as randomly sampling the space of all scale-free
networks with a given degree exponent $\gamma$. We generate viable realisation
with finite $N$ for $1\ll \gamma<2$ as well as $\gamma>2$. We observe an
apparently discontinuous transition at $\gamma\approx 2$ between so-called
super-star networks and more tree-like realisations. Gradually increasing
$\gamma$ further leads to re-emergence of a super-star hub. To quantify these
structural features we derive a new analytic expression for the expected degree
exponent of a pure preferential attachment process, and introduce alternative
measures of network entropy. Our approach is generic and may also be applied to
an arbitrary degree distribution.


title:
Adaptive function estimation in nonparametric regression with one-sided
  errors

abstract:
  We consider the model of nonregular nonparametric regression where smoothness
constraints are imposed on the regression function $f$ and the regression
errors are assumed to decay with some sharpness level at their endpoints. The
aim of this paper is to construct an adaptive estimator for the regression
function $f$. In contrast to the standard model where local averaging is
fruitful, the nonregular conditions require a substantial different treatment
based on local extreme values. We study this model under the realistic setting
in which both the smoothness degree $\beta>0$ and the sharpness degree
$\mathfrak {a}\in(0,\infty)$ are unknown in advance. We construct adaptation
procedures applying a nested version of Lepski's method and the negative Hill
estimator which show no loss in the convergence rates with respect to the
general $L_q$-risk and a logarithmic loss with respect to the pointwise risk.
Optimality of these rates is proved for $\mathfrak{a}\in(0,\infty)$. Some
numerical simulations and an application to real data are provided.


title:
Certifying Machine Code Safe from Hardware Aliasing: RISC is not
  necessarily risky

abstract:
  Sometimes machine code turns out to be a better target for verification than
source code. RISC machine code is especially advantaged with respect to source
code in this regard because it has only two instructions that access memory.
That architecture forms the basis here for an inference system that can prove
machine code safe against `hardware aliasing', an effect that occurs in
embedded systems. There are programming memes that ensure code is safe from
hardware aliasing, but we want to certify that a given machine code is provably
safe.


title: The Complexity of the Proper Orientation Number

abstract:
  Graph orientation is a well-studied area of graph theory. A proper
orientation of a graph $G = (V,E)$ is an orientation $D$ of $E(G)$ such that
for every two adjacent vertices $ v $ and $ u $, $ d^{-}_{D}(v) \neq
d^{-}_{D}(u)$ where $d_{D}^{-}(v)$ is the number of edges with head $v$ in $D$.
The proper orientation number of $G$ is defined as $ \overrightarrow{\chi} (G)
=\displaystyle \min_{D\in \Gamma} \displaystyle\max_{v\in V(G)} d^{-}_{D}(v) $
where $\Gamma$ is the set of proper orientations of $G$. We have $ \chi(G)-1
\leq \overrightarrow{\chi} (G)\leq \Delta(G) $. We show that, it is $
\mathbf{NP} $-complete to decide whether $\overrightarrow{\chi}(G)=2$, for a
given planar graph $G$. Also, we prove that there is a polynomial time
algorithm for determining the proper orientation number of 3-regular graphs. In
sharp contrast, we will prove that this problem is $ \mathbf{NP} $-hard for
4-regular graphs.


title: Non-Abelian Phases from a Quantum Zeno Dynamics

abstract:
  A connection is estabilished between the non-Abelian phases obtained via
adiabatic driving and those acquired via a quantum Zeno dynamics induced by
repeated projective measurements. In comparison to the adiabatic case, the Zeno
dynamics is shown to be more flexible in tuning the system evolution, which
paves the way to the implementation of unitary quantum gates and applications
in quantum control.


title:
Highly-Efficient Charge Separation and Polaron Delocalization in
  Polymer-Fullerene Bulk-Heterojunctions: A Comparative Multi-Frequency EPR &
  DFT Study

abstract:
  The ongoing depletion of fossil fuels has led to an intensive search for
additional renewable energy sources. Solar-based technologies could provide
sufficient energy to satisfy the global economic demands in the near future.
Photovoltaic (PV) cells are the most promising man-made devices for direct
solar energy utilization. Understanding the charge separation and charge
transport in PV materials at a molecular level is crucial for improving the
efficiency of the solar cells. Here, we use light-induced EPR spectroscopy
combined with DFT calculations to study the electronic structure of charge
separated states in blends of polymers (P3HT, PCDTBT, and PTB7) and fullerene
derivatives (C60-PCBM and C70-PCBM). Solar cells made with the same composites
as active layers show power conversion efficiencies of 3.3% (P3HT), 6.1%
(PCDTBT), and 7.3% (PTB7), respectively. Under illumination of these
composites, two paramagnetic species are formed due to photo-induced electron
transfer between the conjugated polymer and the fullerene. They are the
positive, P+, and negative, P-, polarons on the polymer backbone and fullerene
cage, respectively, and correspond to radical cations and radical anions. Using
the high spectral resolution of high-frequency EPR (130 GHz), the EPR spectra
of these species were resolved and principal components of the g-tensors were
assigned. Light-induced pulsed ENDOR spectroscopy allowed the determination of
1H hyperfine coupling constants of photogenerated positive and negative
polarons. The experimental results obtained for the different polymer-fullerene
composites have been compared with DFT calculations, revealing that in all
three systems the positive polaron is distributed over distances of 40-60 A on
the polymer chain. This corresponds to about 15 thiophene units for P3HT,
approximately three units PCDTBT, and about three to four units for PTB7. No
spin density...


title: Bounding the volumes of singular weak log del Pezzo surfaces

abstract:
  We give an optimal upper bound for the anti-canonical volume of an
$\epsilon$-lc weak log del Pezzo surface. Moreover, we consider the relation
between the bound of the volume and the Picard number of the minimal resolution
of the surface. Furthermore we consider blowing up several points on a
Hirzebruch surface in general position and give some examples of smooth weak
log del Pezzo surfaces.


title: Failure of the local-to-global property for CD(K,N) spaces

abstract:
  Given any K and N we show that there exists a compact geodesic metric measure
space satisfying locally the CD(0,4) condition but failing CD(K,N) globally.
The space with this property is a suitable non convex subset of R^2 equipped
with the l^\infty-norm and the Lebesgue measure. Combining many such spaces
gives a (non compact) complete geodesic metric measure space satisfying CD(0,4)
locally but failing CD(K,N) globally for every K and N.


title: Shape evolution of giant resonances in Nd and Sm isotopes

abstract:
  Giant multipole resonances in Nd and Sm isotopes are studied by employing the
quasiparticle-random-phase approximation on the basis of the Skyrme
energy-density-functional method. Deformation effects on giant resonances are
investigated in these isotopes which manifest a typical nuclear shape change
from spherical to prolate shapes. The peak energy, the broadening, and the
deformation splitting of the isoscalar giant monopole (ISGMR) and quadrupole
(ISGQR) resonances agree well with measurements. The magnitude of the peak
splitting and the fraction of the energy-weighted strength in the lower peak of
the ISGMR reflect the nuclear deformation. The experimental data on ISGMR,
ISGDR, and ISGQR are consistent with the nuclear-matter incompressibility $K
\simeq 210-230$ MeV and the effective mass $m^*_0/m \simeq 0.8-0.9$. However,
the high-energy octupole resonance (HEOR) in $^{144}$Sm seems to indicates a
smaller effective mass, $m^*_0/m \simeq 0.7-0.8$. A further precise measurement
of HEOR is desired to determine the effective mass.


title: Topological Hochschild homology and the Bass trace conjecture

abstract:
  We use the methods of topological Hochschild homology to shed new light on
the groups satisfying the Bass trace conjecture. We show that the factorization
of the Hattori-Stallings rank map through the Bokstedt-Hsiang-Madsen cyclotomic
trace map leads to Linnell's restriction on such groups. As a new consequence
of this restriction, we show that the conjecture holds for any group G with the
property that every subgroup that is isomorphic to the additive group of
rational numbers has nontrivial and central image in some quotient of G.


title: Vertex Algebras and the Equivariant Lie Algebroid Cohomology

abstract:
  A vertex-algebraic analogue of the Lie algebroid complex is constructed,
which generalizes the "small" chiral de Rham complex on smooth manifolds. The
notion of VSA-inductive sheaves is also introduced. This notion generalizes
that of sheaves of vertex superalgebras. The complex mentioned above is
constructed as a VSA-inductive sheaf. With this complex, the equivariant Lie
algebroid cohomology is generalized to a vertex-algebraic analogue, which we
call the chiral equivariant Lie algebroid cohomology. In fact, the notion of
the equivariant Lie algebroid cohomology contains that of the equivariant
Poisson cohomology. Thus the chiral equivariant Lie algebroid cohomology is
also a vertex-algebraic generalization of the equivariant Poisson cohomology. A
special kind of complex is introduced and its properties are studied in detail.
With these properties, some isomorphisms of cohomologies are developed, which
enables us to compute the chiral equivariant Lie algebroid cohomology in some
cases. Poisson-Lie groups are considered as such a special case.


title: Finite p-groups with central automorphism group of minimal order

abstract:
  We study finite p-groups G of coclass upto 4 for which the group Aut_z(G) of
all central automorphisms of G is of minimal possible order. As a consequence,
we obtain very short and elementary proofs of main results of Sharma and Gumber
[7].


title: Matrices of forests, analysis of networks, and ranking problems

abstract:
  The matrices of spanning rooted forests are studied as a tool for analysing
the structure of networks and measuring their properties. The problems of
revealing the basic bicomponents, measuring vertex proximity, and ranking from
preference relations / sports competitions are considered. It is shown that the
vertex accessibility measure based on spanning forests has a number of
desirable properties. An interpretation for the stochastic matrix of
out-forests in terms of information dissemination is given.


title:
Updated limits on diffuse fluxes of cosmic neutrinos with 2008-2011
  ANTARES data

abstract:
  The ANTARES neutrino telescope detects the Cherenkov radiation emitted along
the path of charged particles produced in neutrino interactions. ANTARES is
sensitive to all flavors even though it is optimized for muon neutrinos.
Several algorithms estimating the deposited energy in the active volume of the
detector have been developed and applied to the reconstruction of the primary
neutrino energy - this allows to improve the search for a diffuse flux of
astrophysical neutrinos. The search for a diffuse flux of cosmic neutrinos at
very high energies (E_\nu > 30 TeV) is updated using 4 years of data with the
full detector.


title: Elliptic flow of thermal photons from event-by-event hydrodynamic model

abstract:
  Elliptic flow of direct photons in relativistic heavy ion collisions is
believed to be dominated by contribution from thermal radiation of quark gluon
plasma up to $p_T$ $\sim 5$ GeV/$c$, although other sources start outshining
the thermal contribution at already smaller values of $p_T$ in the direct
photon spectrum. The elliptic flow of thermal photons from ideal hydrodynamics
considering a smooth initial density distribution under-predicts the PHENIX
direct photon data from 200A GeV Au+Au collisions at RHIC by a large margin in
the range $1 < p_T < 5$ GeV/$c$. However, a significant enhancement of thermal
photon production due to fluctuations in the initial QCD matter density
distributions is expected. We show that such fluctuations result in
substantially larger photon elliptic flow for $p_T > 2.5 $ GeV/$c$ compared to
a smooth initial-state-averaged density profile. The results from
event-by-event hydrodynamics are found to be sensitive to the fluctuation size
parameter. However, the effects of initial state fluctuations are insufficient
to account for the discrepancy to the PHENIX data for direct photon elliptic
flow. Furthermore, the photon $v_2$ is reduced even more when we include the
NLO pQCD prompt photon component. We also calculate the spectra and elliptic
flow of thermal photons for 2.76A TeV Pb+Pb collisions at LHC and for the
0--40% centrality bin. Thermal photons from event-by-event hydrodynamics along
with prompt photons from NLO pQCD calculations explain the ALICE preliminary
direct photon data well in the region $p_T \ge 2.5$ GeV/c. Similar to RHIC, the
elliptic flow results at LHC are again found to be much smaller than the ALICE
preliminary $v_2$ data.


title: Red supergiant star studies with CO5BOLD and Optim3D

abstract:
  We describe recent work focused towards a better understanding of red
supergiant stars using 3D radiative-hydrodynamics (RHD) simulations with
CO5BOLD. A small number of simulations now exist that span up to seven years of
stellar time, at various numerical resolutions. Our discussion concentrates on
interferometric and spectroscopic observations. We point out a number of
problems, in particular the line depth and line width that are not well
reproduced by simulations. The most recent introduction of a non-grey treatment
of the radiation field dramatically improved the match with observations,
without solving all difficulties. We also review the newly revived effective
temperature scale controversy, and argue that it will only be solved using 3D
RHD models.


title:
Gluon bremsstrahlung by heavy quarks - its effects on transport
  coefficients and equilibrium distribution

abstract:
  The effects of gluon radiation by charm quarks on the transport coefficients
{\it e.g.} drag, longitudinal and transverse diffusion and shear viscosity have
been studied within the ambit of perturbative quantum chromodynamics (pQCD) and
kinetic theory. We found that while the soft gluon radiation has substantial
effects on the transport coefficients of the charm quarks in the quark gluon
plasma its effects on the equilibrium distribution function is insignificant.


title:
Probing Majorana Flat Bands in Nodal $d_{x^2-y^2}$-wave Superconductors
  with Rashba Spin-Orbit Coupling

abstract:
  We show that Majorana fermions associated with Majorana flat bands emerge as
zero energy modes on the [110] edge of single layer or multilayer nodal
superconductors with $d_{x^2-y^2}$-wave pairing and Rashba spin-orbit coupling.
Moreover, as long as the global inversion symmetry of the single layer or
multilayer superconductor is broken, and in the presence of an in-plane
magnetic field parallel to the [110] edge, the Majorana fermions together with
usual fermionic Andreev bound states induce a triple-peak structure in
tunnelling spectroscopy experiments. Importantly, we show that the zero bias
conductance peak is induced by Majorana fermions. Therefore, tunnelling
spectroscopy can be used to probe Majorana fermions in nodal $d_{x^2-y^2}$-wave
superconductors.


title:
Can structure formation distinguish \Lambda CDM from non-minimal f(R)
  Gravity?

abstract:
  Non-minimally coupled f(R) gravity model is an interesting approach to
explain the late time acceleration of the Universe without introducing any
exotic matter component in the energy budget of the Universe. But
distinguishing such model with the concordance \Lambda CDM model using present
observational data is a serious challenge. In this paper, we address this issue
using the observations related to the growth of matter over density g(z) as
measured by different galaxy surveys. As background cosmology is not sufficient
to distinguish different dark energy models, we first find out the functional
form for f(R) (which is non-minimally coupled to the matter lagrangian) that
produces the similar background cosmology as in \Lambda CDM. Subsequently we
calculate the growth for the matter over density g(z) for such non minimally
coupled f(R) models and compare them with the \Lambda CDM Universe. We also use
the measurements of g(z)\sigma_{8}(z) by different galaxy surveys to
reconstruct the behavior for g(z) and \sigma_{8}(z) for both the non-minimally
coupled f(R) gravity models as well as for the \Lambda CDM. Our results show
that there is a small but finite window where one can distinguish the
non-minimally coupled f(R) models with the concordance \Lambda CDM.


title: How big is the minimum of a branching random walk?

abstract:
  Let $M_n$ be the minimal position at generation $n$, of a real-valued
branching random walk in the boundary case. As $n \to \infty$, $M_n- {3 \over
2} \log n$ is tight (see [1][9][2]). We establish here a law of iterated
logarithm for the upper limits of $M_n$: upon the system's non-extinction, $
\limsup\_{n\to \infty} {1\over \log \log \log n} ( M_n - {3\over2} \log n) = 1$
almost surely. We also study the problem of moderate deviations of $M_n$:
$p(M_n- {3 \over 2} \log n > \lambda)$ for $\lambda\to \infty$ and
$\lambda=o(\log n)$. This problem is closely related to the small deviations of
a class of Mandelbrot's cascades.


title: Metabolic Control Analysis: Rereading Reder

abstract:
  Metabolic control analysis is a biochemical formalism defined by Kacser and
Burns in 1973, and given firm mathematical basis by Reder in 1988. The
algorithm defined by Reder for calculating the control matrices is still used
by software programs today, but is only valid for some biochemical models. We
show that, with slight modification, the algorithm may be applied to all
models.


title:
A Bhatnagar-Gross-Krook Approximation to Stochastic Scalar Conservation
  Laws

abstract:
  We study a BGK-like approximation to hyperbolic conservation laws forced by a
multiplicative noise. First, we make use of the stochastic characteristics
method and establish the existence of a solution for any fi xed parameter
$\varepsilon$. In the next step, we investigate the limit as $\varepsilon$
tends to 0 and show the convergence to the kinetic solution of the limit
problem.


title: Data Leak Aware Crowdsourcing in Social Network

abstract:
  Harnessing human computation for solving complex problems call spawns the
issue of finding the unknown competitive group of solvers. In this paper, we
propose an approach called Friendlysourcing to build up teams from social
network answering a business call, all the while avoiding partial solution
disclosure to competitive groups. The contributions of this paper include (i) a
clustering based approach for discovering collaborative and competitive team in
social network (ii) a Markov-chain based algorithm for discovering implicit
interactions in the social network.


title: Transport Properties of Topological Insulators Films and Nanowires

abstract:
  The last several years have witnessed the rapid developments in the study and
understanding of topological insulators. In this review, after a brief summary
of the history of topological insulators, we focus on the recent progress made
in transport experiments on topological insulator films and nanowires. Some
quantum phenomena, including the weak antilocalization, the Aharonov Bohm
effect and the Shubnikov de Haas oscillations, observed in these nanostructures
are described. In addition, the electronic transport evidence of the
superconducting proximity effect as well as an anomalous resistance enhancement
in topological insulator/superconductor hybrid structures is included.


title:
Outflow forces of low mass embedded objects in Ophiuchus: a quantitative
  comparison of analysis methods

abstract:
  The outflow force of molecular bipolar outflows is a key parameter in
theories of young stellar feedback on their surroundings. The focus of many
outflow studies is the correlation between the outflow force, bolometric
luminosity and envelope mass. However, it is difficult to combine the results
of different studies in large evolutionary plots over many orders of magnitude
due to the range of data quality, analysis methods and corrections for
observational effects such as opacity and inclination. We aim to determine the
outflow force for a sample of low luminosity embedded sources. We will quantify
the influence of the analysis method and the assumptions entering the
calculation of the outflow force. We use the James Clerk Maxwell Telescope to
map 12CO J=3-2 over 2'x2' regions around 16 Class I sources of a well-defined
sample in Ophiuchus at 15" resolution. The outflow force is then calculated
using seven different methods differing e.g. in the use of intensity-weighted
emission and correction factors for inclination. The results from the analysis
methods differ from each other by up to a factor of 6, whereas observational
properties and choices in the analysis procedure affect the outflow force by up
to a factor of 4. For the sample of Class I objects, bipolar outflows are
detected around 13 sources including 5 new detections, where the three
non-detections are confused by nearby outflows from other sources. When
combining outflow forces from different studies, a scatter by up to a factor of
5 can be expected. Although the true outflow force remains unknown, the
separation method (separate calculation of dynamical time and momentum) is
least affected by the uncertain observational parameters. The correlations
between outflow force, bolometric luminosity and envelope mass are further
confirmed down to low luminosity sources.


title: Phase stacking diagram of colloidal mixtures under gravity

abstract:
  The observation of stacks of distinct layers in a colloidal or liquid mixture
in sedimentation-diffusion equilibrium is a striking consequence of bulk phase
separation. Drawing quantitative conclusions about the phase diagram is,
however, very delicate. Here we introduce the Legendre transform of the
chemical potential representation of the bulk phase diagram to obtain a unique
stacking diagram of all possible stacks under gravity. Simple bulk phase
diagrams generically lead to complex stacking diagrams. We apply the theory to
a binary hard core platelet mixture with only two-phase bulk coexistence, and
find that the stacking diagram contains six types of stacks with up to four
distinct layers. These results can be tested experimentally in colloidal
platelet mixtures. In general, an extended Gibbs phase rule determines the
maximum number of sedimented layers to be $3+2(n_b-1)+n_i$, where $n_b$ is the
number of binodals and $n_i$ is the number of their inflection points.


title:
Bistable generalised Langevin dynamics driven by correlated noise
  possessing a long jump distribution: barrier crossing and stochastic
  resonance

abstract:
  The generalised Langevin equation with a retarded friction and a double-well
potential is solved. The random force is modelled by a multiplicative noise
with long jumps. Probability density distributions converge with time to a
distribution similar to a Gaussian but tails have a power-law form. Dependence
of the mean first passage time on model parameters is discussed. Properties of
the stochastic resonance, emerging as a peak in the plot of the spectral
amplification against the temperature, are discussed for various sets of the
model parameters. The amplification rises with the memory and is largest for
the cases corresponding to the large passage time.


title: B -> K(*) l+ l- @ Low Recoil and Physics Implications

abstract:
  This talk covers recent theoretical progress in exclusive semileptonic rare
B-decays at low hadronic recoil. The efficient parametric suppression of the
1/mb corrections in this region provides opportunities to probe the Standard
Model and beyond at precision level. Notably, angular analysis allows to
simultaneously access electroweak flavor physics and hadronic matrix elements,
the latter of which constitute the leading source of theoretical uncertainty.
Ratios of B ->K* form factors can already be extracted from present data. A
comparison with existing theoretical determinations by lattice QCD and light
cone sum rules gives a consistent picture over the whole kinematic range. In
the future improved analyses will advance our understanding of non-perturbative
methods for QCD and of |Delta B|=1 transitions.


title: Tetraquarks, their Masses and Decays in QED_2

abstract:
  Recent observations by Belle and BESIII of charged quarkonium-like resonances
give new stimulus for theoretical investigation of exotic hadrons in general
and heavy tetraquarks in particular. We use QED_2, a confining theory, as a
model for the masses and decays of tetraquarks. Here we discuss the states (Q
Qbar q qbar) and (Q Q qbar qbar) (and its anti-particle), where Q and q are two
fermion flavors with masses M and m, so that M > m. We then discuss decay modes
of these states into (Q Qqbar), (q qbar), (Q qbar), (Qbar q). It turns out that
(Q Qbar q qbar) is stable, while (Q Q qbar qbar) is not.


title: Azimuthal Jet Tomography of Quark Gluon Plasmas at RHIC and LHC

abstract:
  Recent data on the azimuthal and transverse momentum dependence of high-pT>10
GeV pion nuclear modification factors in nuclear collisions at RHIC/BNL and
LHC/CERN are analyzed in terms of a wide class of jet-energy loss models and a
variety of transverse expanding collective flow backgrounds. RHIC data at 200
AGeV are found to be surprisingly consistent with rather different dE/dx models
when coupled to recent 2+1D minimally viscous QGP flow field predictions.
However, extrapolations to LHC, with parameters fixed at RHIC, favor running
coupling QCD based energy-loss models over fixed coupling QCD, conformal AdS
holography, or Tc-dominated jet-energy loss models that tend to overpredict jet
quenching at the LHC.


title: Parasitic interference in nulling interferometry

abstract:
  Nulling interferometry aims to detect faint objects close to bright stars.
Its principle is to produce a destructive interference along the line-of-sight
so that the stellar flux is rejected, while the flux of the off-axis source can
be transmitted. In practice, various instrumental perturbations can degrade the
nulling performance. Any imperfection in phase, amplitude, or polarization
produces a spurious flux that leaks to the interferometer output and corrupts
the transmitted off-axis flux. One of these instrumental pertubations is the
crosstalk phenomenon, which occurs because of multiple parasitic reflections
inside transmitting optics, and/or diffraction effects related to beam
propagation along finite size optics. It can include a crosstalk of a beam with
itself, and a mutual crosstalk between different beams. This can create a
parasitic interference pattern, which degrades the intrinsic transmission map -
or intensity response - of the interferometer. In this context, we describe how
this instrumental effect impairs the performance of a Bracewell interferometer.
A simple formalism is developed to derive the corresponding modified intensity
response of the interferometer, as a function of the two parameters of
interest: the crosstalk level (or contamination rate) and the phase shift
between the primary and secondary - parasitic - beams. We then apply our
mathematical approach to a few scientific cases, both analytically and using
the GENIEsim simulation software, adapted to handle coherent crosstalk. Our
results show that a coherent crosstalk level of about 1% implies a 20% drop of
the SNR at most. Careful attention should thus be paid to reduce the crosstalk
level inside an interferometric instrument and ensure an instrumental stability
that provides the necessary sensitivity through calibration procedures.


title: Optical bistability in strong-coupling cavity QED with a few atoms

abstract:
  We present exact numerical solutions of the damped-driven Jaynes--Cummings
model adapted to describe absorptive optical bistability in the limit of a few
atoms strongly coupled to a high-finesse resonator. We show that the
simplifying semiclassical result for many physical quantities of interest is
well reproduced by the quantum model including even with only a few atoms in
the strongly coupled system. Nontrivial atom-field quantum cross-correlations
show up in the strong-driving limit.


title: Observation of vibrating systems at different time instants

abstract:
  In this paper, we obtain new observability inequalities for the vibrating
string. This work was motivated by a recent paper by A. Szij\'art\'o and J.
Heged\H{u}s in which the authors ask the question of determining the initial
data by only knowing the position of the string at two distinct time instants.
The choice of the observation instants is crucial and the estimations rely on
the Fourier series expansion of the solutions and results of Diophantine
approximation.


title: Painleve Equations and Complex Reflections

abstract:
  We will explain how some new algebraic solutions of the sixth Painleve
equation arise from complex reflection groups, thereby extending some results
of Hitchin and Dubrovin-Mazzocco for real reflection groups. The problem of
finding explicit formulae for these solutions will be addressed elsewhere.


title:
The intermediate vertex subalgebras of the lattice vertex operator
  algebras

abstract:
  A notion of intermediate vertex subalgebras of lattice vertex operator
algebras is introduced, as a generalization of the notion of principal
subspaces. Bases and the graded dimensions of such subalgebras are given.As an
application, it is shown that the characters of some modules of an intermediate
vertex subalgebra between $E_7$ and $E_8$ lattice vertex operator algebras
satisfy some modular differential equations.This result is an analogue of the
result concerning the "hole" of the Deligne dimension formulas and the
intermediate Lie algebra between the simple Lie algebras $E_7$ and $E_8$.


title:
Tree-level contribution to \bar{B} -> X_d gamma using fragmentation
  functions

abstract:
  We evaluate the most important tree-level contributions connected with the
b-> u \bar{u} d gamma transition to the inclusive radiative decay \bar{B}-> X_d
gamma using fragmentation functions. In this framework the singularities
arising from collinear photon emission from the light quarks (u, \bar{u} and d)
can be absorbed into the (bare) quark-to-photon fragmentation function. We use
as input the fragmentation function extracted by the ALEPH group from the
two-jet cross section measured at LEP, where one of the jets is required to
contain a photon. To get the quark-to-photon fragmentation function at the
fragmentation scale \mu_F \sim m_b, we use the evolution equation, which we
solve numerically. We then calculate the (integrated) photon energy spectrum
for b-> u \bar{u} d gamma related to the operators P^u_{1,2}. For comparison,
we also give the corresponding results when using nonzero (constituent) masses
for the light quarks.


title: Through the analytic halo: Fission via irregular singularities

abstract:
  This article is concerned with moduli spaces of connections on bundles on
Riemann surfaces, where the structure group of the bundle may vary in different
regions of the surface. Here we will describe such moduli spaces as complex
symplectic manifolds, generalising the complex character varieties of Riemann
surfaces.


title: On equivariant characteristic ideals of real classes

abstract:
  Let $p$ be an odd prime, $F/{\Bbb Q}$ an abelian totally real number field,
$F_\infty/F$ its cyclotomic ${\Bbb Z}_p$-extension, $G_\infty = Gal (F_\infty /
{\Bbb Q}),$ ${\Bbb A} = {\Bbb Z}_p [[G_\infty]].$
  We give an explicit description of the equivariant characteristic ideal of
$H^2_{Iw} (F_\infty, {\Bbb Z}_p(m))$ over ${\Bbb A}$ for all odd $m \in {\Bbb
Z}$ by applying M. Witte's formulation of an equivariant main conjecture (or
"limit theorem") due to Burns and Greither. This could shed some light on
Greenberg's conjecture on the vanishing of the $\lambda$-invariant of
$F_\infty/F.$


title:
A Class of Inert N-tuplet Models with Radiative Neutrino Mass and Dark
  Matter

abstract:
  We present a class of models with radiative neutrino mass and stable
dark-matter candidates. Neutrino mass is generated by a one-loop diagram with
the same topography as Ma's 2006 proposal (which used an inert scalar-doublet
and singlet fermion). We generalize this approach and determine all variants
with new fields no larger than the adjoint representation. When the neutrino
mass diagram contains a Majorana mass insertion there are two possibilities,
both of which are known. If the mass insertion is of the Dirac type there are
seven additional models, two of which are excluded by direct-detection
experiments. The other five models are also constrained, such that only scalar
dark-matter is viable. There are cases with an inert singlet, an inert doublet,
and an inert triplet, providing a natural setting for inert N-tuplet models of
dark matter, with the additional feature of achieving radiative neutrino mass.
We show that some of the models admit a simple explanation for the (requisite)
discrete symmetry, and briefly discuss cases with representations larger than
the adjoint, which can admit a connection to the astrophysical gamma-ray
signal.


title:
Soft-gluon Resummation for High-pT Inclusive-Hadron Production at
  COMPASS

abstract:
  We study the cross section for the photoproduction reaction gamma N -> h X in
fixed-target scattering at COMPASS, where the hadron h is produced at large
transverse momentum. We investigate the role played by higher-order QCD
corrections to the cross section. In particular we address large logarithmic
"threshold" corrections to the rapidity dependent partonic cross sections,
which we resum to all orders at next-to-leading accuracy. In our comparison to
the experimental data we find that the threshold contributions are large and
improve the agreement between data and theoretical predictions significantly.


title:
A search for CII-158$\mu$m line emission in HCM\,6A, a Lyman-$\alpha$
  emitter at $z=6.56$

abstract:
  We report a Plateau de Bure interferometer search for CII-158$\mu$m emission
from HCM6A, a lensed Lyman-$\alpha$ emitter (LAE) at $z = 6.56$. Our
non-detections of CII-158$\mu$m line emission and 1.2mm radio continuum
emission yield $3\sigma$ limits of L$_{\rm CII} < 6.4 \times 10^7 \times
(\Delta V/100 km s^{-1})^{1/2}$ L$_\odot$ on the CII-158$\mu$m line luminosity
and S$_{\rm 1.2mm} < 0.68$ mJy on the 1.2mm flux density. The local conversion
factor between L$_{\rm CII}$ and star formation rate (SFR) yields an SFR $<
4.7$ M$_\odot$ yr$^{-1}$, $\approx 2$ times lower than that inferred from the
ultraviolet (UV) continuum, suggesting that the local factor may not be
applicable in high-$z$ LAEs. The non-detection of 1.2mm continuum emission
yields a total SFR $< 28$ M$_\odot$/yr; any obscured star formation is thus
within a factor of two of the visible star formation. Our best-fit model to the
rest-frame UV/optical spectral energy distribution of HCM6A yields a stellar
mass of $1.3 \times 10^9$ M$_\odot$ and an SFR of ~10 M$_\odot$/yr, with
negligible dust obscuration. We fortuitously detect CO J=3-2 emission from a
$z=0.375$ galaxy in the foreground cluster Abell370, obtaining a CO line
luminosity of L$^\prime ({\rm CO}) > (8.95 \pm 0.79) \times 10^8$ K km s$^{-1}$
pc$^2$, and a molecular gas mass of M$({\rm H_2}) > (4.12 \pm 0.36) \times
10^9$ M$_\odot$, for a CO-to-H$_2$ conversion factor of 4.6 M$_\odot$ (K km
s$^{-1}$ pc$^2$)$^{-1}$.


title:
Editorial note to "A Homogeneous Universe of Constant Mass and
  Increasing Radius accounting for the Radial Velocity of Extra--Galactic
  Nebulae" by Georges Lema\^itre (1927)

abstract:
  This is an editorial note to accompany printing as a Golden Oldie in the
Journal of General Relativity and Gravitation of the fundamental article by
Georges Lema\^itre first published in French in 1927, in which the author
provided the first explanation of the observations on the recession velocities
of galaxies as a natural consequence of dynamical cosmological solutions of
Einstein's field equations, and discovered the so-called Hubble law. We analyze
in detail the scientific contents of this outstanding work, we describe how it
remained unread or poorly appreciated until 1930, and we list and explain the
differences between the 1927 and 1931 versions. Indeed the English translation
published in 1931 in MNRAS was not perfectly faithful to the original text - it
was updated. As it turned out very recently, the updates were done by
Lema\^itre himself, but the discrepancies between the two texts caused a
temporary stir among historians. Our new translation - given in the Appendix -
follows the 1927 version exactly.


title: Local connection forms revisited

abstract:
  Local connection forms provide a very useful tool for handling connections on
principal bundles, because they ignore any complexities of the total space and,
essentially, involve only two fundamental features of the structure group,
namely the adjoint representation and the left (logarithmic) differential. The
main results of this note characterize connections related together by bundle
morphisms, while applications (taken from various sources) refer to connections
on (Banach) associated bundles, in particular vector bundles, and connections
on inverse limit bundles (in the Fr\'echet framework). The role of local
connection forms is further illustrated by their sheaf-theoretic globalization,
resulting in a sheaf operator-like approach to principal connections. The
latter point of view is naturally leading to a theory of connections on
abstract principal sheaves.


title:
Quantum Fluctuation Driven First-order Phase Transitions in Optical
  Lattices

abstract:
  We study quantum fluctuation driven first-order phase transitions of a
two-species bosonic system in a three-dimensional optical lattice. Using
effective potential method we find that the superfluid-Mott insulator phase
transition of one type of bosons can be changed from second-order to
first-order by the quantum fluctuations of the other type of bosons. The study
of the scaling behaviors near the quantum critical point shows that the
first-order phase transition has a different universality from the second-order
one. We also discuss the observation of this exotic phenomenon in the realistic
cold-atom experiments.


title: Two-loop Wess-Zumino model with exact supersymmetry on the lattice

abstract:
  We consider a lattice formulation of the four dimensional N=1 Wess-Zumino
model in terms of the Ginsparg-Wilson relation. This formulation has an exact
supersymmetry on the lattice. The lattice action is invariant under a deformed
supersymmetric transformation which is non-linear in the scalar fields and it
is determined by an iterative procedure in the coupling constant to all orders
in perturbation theory. We also show that the corresponding Ward-Takahashi
identity is satisfied at fixed lattice spacing. The calculation is performed in
lattice perturbation theory up to order $g^3$ (two-loop) and the Ward-Takahashi
identity (containing 110 connected non-tadpole Feynman diagrams) is satisfied
at fixed lattice spacing thanks to this exact lattice supersymmetry.


title: Configurable Strategies for Work-stealing

abstract:
  Work-stealing systems are typically oblivious to the nature of the tasks they
are scheduling. For instance, they do not know or take into account how long a
task will take to execute or how many subtasks it will spawn. Moreover, the
actual task execution order is typically determined by the underlying task
storage data structure, and cannot be changed. There are thus possibilities for
optimizing task parallel executions by providing information on specific tasks
and their preferred execution order to the scheduling system.
  We introduce scheduling strategies to enable applications to dynamically
provide hints to the task-scheduling system on the nature of specific tasks.
Scheduling strategies can be used to independently control both local task
execution order as well as steal order. In contrast to conventional scheduling
policies that are normally global in scope, strategies allow the scheduler to
apply optimizations on individual tasks. This flexibility greatly improves
composability as it allows the scheduler to apply different, specific
scheduling choices for different parts of applications simultaneously. We
present a number of benchmarks that highlight diverse, beneficial effects that
can be achieved with scheduling strategies. Some benchmarks (branch-and-bound,
single-source shortest path) show that prioritization of tasks can reduce the
total amount of work compared to standard work-stealing execution order. For
other benchmarks (triangle strip generation) qualitatively better results can
be achieved in shorter time. Other optimizations, such as dynamic merging of
tasks or stealing of half the work, instead of half the tasks, are also shown
to improve performance. Composability is demonstrated by examples that combine
different strategies, both within the same kernel (prefix sum) as well as when
scheduling multiple kernels (prefix sum and unbalanced tree search).


title: Effective run-and-tumble dynamics of bacteria baths

abstract:
  {\it E. coli} bacteria swim in straight runs interrupted by sudden
reorientation events called tumbles. The resulting random walks give rise to
density fluctuations that can be derived analytically in the limit of non
interacting particles or equivalently of very low concentrations. However, in
situations of practical interest, the concentration of bacteria is always large
enough to make interactions an important factor. Using molecular dynamics
simulations, we study the dynamic structure factor of a model bacterial bath
for increasing values of densities. We show that it is possible to reproduce
the dynamics of density fluctuations in the system using a free run-and-tumble
model with effective fitting parameters. We discuss the dependence of these
parameters, e.g., the tumbling rate, tumbling time and self-propulsion
velocity, on the density of the bath.


title:
Generalized Plasma Dispersion Function: One-Solve-All Treatment,
  Visualizations, and Application to Landau Damping

abstract:
  A unified, fast, and effective approach is developed for numerical
calculation of the well-known plasma dispersion function with extensions from
Maxwellian distribution to almost arbitrary distribution functions, such as the
$\delta$, flat top, triangular, $\kappa$ or Lorentzian, slowing down, and
incomplete Maxwellian distributions. The singularity and analytic continuation
problems are also solved generally. Given that the usual conclusion
$\gamma\propto\partial f_0/\partial v$ is only a rough approximation when
discussing the distribution function effects on Landau damping, this approach
provides a useful tool for rigorous calculations of the linear wave and
instability properties of plasma for general distribution functions. The
results are also verified via a linear initial value simulation approach.
Intuitive visualizations of the generalized plasma dispersion function are also
provided.


title: A model for the ESR-STM phenomenon

abstract:
  We propose a model to account for the observed ESR-like signal at the Larmor
frequency in the current noise STM experiments identifying spin centers on
various substrates. The theoretical understanding of this phenomenon, which
allows for single spin detection on surfaces at room temperature, is not
settled for the experimentally relevant case that the tip and substrate are not
spin polarized. Our model is based on a direct tip-substrate tunneling in
parallel with a current flowing via the spin states. We find a sharp signal at
the Larmor frequency even at high temperatures, in good agreement with
experimental data. We also evaluate the noise in presence of an ac field near
resonance and predict splitting of the signal by the Rabi frequency.


title:
Single-particle spectral functions in the normal phase of a
  strongly-attractive Bose-Fermi mixture

abstract:
  We calculate the single-particle spectral functions and quasi-particle
dispersions for a Bose-Fermi mixture when the boson-fermion attraction is
sufficiently strong to suppress completely the condensation of bosons at zero
temperature. Within a T-matrix diagrammatic approach, we vary the boson-fermion
attraction from the critical value where the boson condensate first disappears
to the strongly attractive (molecular) regime and study the effect of both
mass- and density-imbalance on the spectral weights and dispersions. An
interesting spectrum of particle-hole excitations mixing two different Fermi
surfaces is found. These unconventional excitations could be produced and
explored experimentally with radio-frequency spectroscopy.


title:
Capacity Value of Additional Generation: Probability Theory and Sampling
  Uncertainty

abstract:
  The concept of capacity value is widely used to quantify the contribution of
additional generation (most notably renewables) within generation adequacy
assessments. This paper surveys the existing probability theory of assessment
of the capacity value of additional generation, and discusses the available
statistical estimation methods for risk measures which depend on the joint
distribution of demand and available additional capacity (with particular
reference to wind).
  Preliminary results are presented on assessment of sampling uncertainty in
hindcast LOLE and capacity value calculations, using bootstrap resampling.
These results indicate strongly that, if the hindcast calculation is dominated
by extremes of demand minus wind, there is very large sampling uncertainty in
the results due to very limited historic experience of high demands coincident
with poor wind resource. For meaningful calculations, some form of statistical
smoothing will therefore be required in distribution estimation.


title:
An efficient implementation of the decoy-state
  measurement-device-independent quantum key distribution with heralded
  single-photon sources

abstract:
  We study the decoy-state measurement-device-independent quantum key
distribution using heralded single-photon sources. This has the advantage that
the observed error rate in X basis is in higher order and not so large. We
calculate the key rate and transmission distance for two cases: one using only
triggered events, and the other using both triggered and non-triggered events.
We compare the key rates of various protocols and find that our new scheme
using triggered and non-triggered events can give higher key rate and longer
secure distance. Moreover, we also show the different behavior of our scheme
when using different heralded single-photon sources, i.e., in poisson or
thermal distribution. We demonstrate that the former can generate a relatively
higher secure key rate than the latter, and can thus work more efficiently in
practical quantum key distributions.


title:
Reversal mechanism of an individual Ni nanotube simultaneously studied
  by torque and SQUID magnetometry

abstract:
  Using an optimally coupled nanometer-scale superconducting quantum
interference device, we measure the magnetic flux originating from an
individual ferromagnetic Ni nanotube attached to a Si cantilever. At the same
time, we detect the nanotube's volume magnetization using torque magnetometry.
We observe both the predicted reversible and irreversible reversal processes. A
detailed comparison with micromagnetic simulations suggests that vortex-like
states are formed in different segments of the individual nanotube. Such
stray-field free states are interesting for memory applications and
non-invasive sensing.


title: A new result on the problem of Buratti, Horak and Rosa

abstract:
  The conjecture of Peter Horak and Alex Rosa (generalizing that of Marco
Buratti) states that a multiset L of v-1 positive integers not exceeding [v/2]
is the list of edge-lengths of a suitable Hamiltonian path of the complete
graph with vertex-set {0,1,...,v-1} if and only if the following condition
(here reformulated in a slightly easier form) is satisfied: for every divisor d
of v, the number of multiples of d appearing in L is at most v-d. In this paper
we do some preliminary discussions on the conjecture, including its
relationship with graph decompositions. Then we prove, as main result, that the
conjecture is true whenever all the elements of L are in {1,2,3,5}.


title: Localized electron states near the armchair edge of graphene

abstract:
  It is known that zigzag graphene edge is able to support edge states: there
is a non-dispersive single-electron band localized near the zigzag edge.
However, it is generally believed that no edge states exist near the armchair
edge. In this paper we re-examine this notion. It is demonstrated that while,
indeed, the pristine armchair edge does not support any localized states, they
do appear if the edge is subjected to suitable modifications (e.g. chemical
functionalization). We explicitly present two types of the edge modification
which support the localized states. Unlike zigzag edge states, which have zero
energy and show no dispersion, properties of the armchair localized states
depend sensitively on the type of edge modification. Under suitable conditions
they demonstrate pronounced dispersion. While the zigzag edge state
wavefunction decays monotonously when we move away from the edge, the armchair
edge state wavefunction shows non-monotonous decay. Such states may be observed
in scanning tunneling spectroscopy experimentally.


title:
Role of MgO barriers for spin and charge transport in Co/MgO/graphene
  non-local spin-valve devices

abstract:
  We investigate spin and charge transport in both single and bilayer graphene
non-local spin-valve devices. Similar to previous studies on bilayer graphene,
we observe an inverse dependence of the spin lifetime on the carrier mobility
in our single layer devices. This general trend is only observed in devices
with large contact resistances. Furthermore, we observe a second Dirac peak in
devices with long spin lifetimes. This results from charge transport underneath
the contacts. In contrast, all devices with low ohmic contact resistances only
exhibit a single Dirac peak. Additionally, the spin lifetime is significantly
reduced indicating that an additional spin dephasing occurs underneath the
electrodes.


title: Genetic recombination is targeted towards gene promoter regions in dogs

abstract:
  The identification of the H3K4 trimethylase, PRDM9, as the gene responsible
for recombination hotspot localization has provided considerable insight into
the mechanisms by which recombination is initiated in mammals. However,
uniquely amongst mammals, canids appear to lack a functional version of PRDM9
and may therefore provide a model for understanding recombination that occurs
in the absence of PRDM9, and thus how PRDM9 functions to shape the
recombination landscape. We have constructed a fine-scale genetic map from
patterns of linkage disequilibrium assessed using high-throughput sequence data
from 51 free-ranging dogs, Canis lupus familiaris. While broad-scale properties
of recombination appear similar to other mammalian species, our fine-scale
estimates indicate that canine highly elevated recombination rates are observed
in the vicinity of CpG rich regions including gene promoter regions, but show
little association with H3K4 trimethylation marks identified in spermatocytes.
By comparison to genomic data from the Andean fox, Lycalopex culpaeus, we show
that biased gene conversion is a plausible mechanism by which the high CpG
content of the dog genome could have occurred.


title:
Emergence of ferromagnetism and Jahn-Teller distortion in low
  Cr-substituted LaMnO3

abstract:
  The emergence of a ferromagnetic component in $LaMnO_{3}$ with low Cr-for-Mn
substitution has been studied by x-ray absorption spectroscopy and x-ray
magnetic circular dichroism at the Mn and Cr K edges. The local magnetic moment
strength for the Mn and Cr are proportional to each other and follows the
macroscopic magnetization. The net ferromagnetic components of $Cr^{3+}$ and
$Mn^{3+}$ are found antiferromagnetically coupled. Unlike hole doping by La
site substitution, the inclusion of $Cr^{3+}$ ions up to x = 0.15 does not
decrease the Jahn-Teller (JT) distortion and consequently does not
significantly affect the orbital ordering. This demonstrates that the emergence
of the ferromagnetism is not related to JT weakening and likely arises from a
complex orbital mixing.


title:
Scaling exponents and phase separation in a nonlinear network model
  inspired by the gravitational accretion

abstract:
  We study dynamics and scaling exponents in a nonlinear network model inspired
by the formation of planetary systems. Dynamics of this model leads to phase
separation to two types of condensate, light and heavy, distinguished by how
they scale with mass. Light condensate distributions obey power laws given in
terms of several identified scaling exponents that do not depend on initial
conditions. The analyzed properties of heavy condensates have been found to be
scale-free. Calculated mass distributions agree well with more complex models,
and fit observations of both our own Solar System, and the best observed
extra-solar planetary systems.

categories: cond-mat.stat-mech astro-ph.EP nlin.AO physics.comp-ph


title:
Frustrated magnetism and resonating valence bond physics in
  two-dimensional kagome-like magnets

abstract:
  We explore the phase diagram and the low-energy physics of three Heisenberg
antiferromagnets which, like the kagome lattice, are networks of corner-sharing
triangles but contain two sets of inequivalent short-distance resonance loops.
We use a combination of exact diagonalization, analytical strong-coupling
theories, and resonating valence bond approaches, and scan through the ratio of
the two inequivalent exchange couplings. In one limit, the lattices effectively
become bipartite, while at the opposite limit heavily frustrated nets emerge.
In between, competing tunneling processes result in short-ranged spin
correlations, a manifold of low-lying singlets (which can be understood as
localized bound states of magnetic excitations), and the stabilization of
valence bond crystals with resonating building blocks.


title:
Social Sensor Placement in Large Scale Networks: A Graph Sampling
  Perspective

abstract:
  Sensor placement for the purpose of detecting/tracking news outbreak and
preventing rumor spreading is a challenging problem in a large scale online
social network (OSN). This problem is a kind of subset selection problem:
choosing a small set of items from a large population so to maximize some
prespecified set function. However, it is known to be NP-complete. Existing
heuristics are very costly especially for modern OSNs which usually contain
hundreds of millions of users. This paper aims to design methods to find
\emph{good solutions} that can well trade off efficiency and accuracy. We first
show that it is possible to obtain a high quality solution with a probabilistic
guarantee from a "{\em candidate set}" of the underlying social network. By
exploring this candidate set, one can increase the efficiency of placing social
sensors. We also present how this candidate set can be obtained using "{\em
graph sampling}", which has an advantage over previous methods of not requiring
the prior knowledge of the complete network topology. Experiments carried out
on two real datasets demonstrate not only the accuracy and efficiency of our
approach, but also effectiveness in detecting and predicting news outbreak.


title: Near-extreme statistics of Brownian motion

abstract:
  We study the statistics of near-extreme events of Brownian motion (BM) on the
time interval [0,t]. We focus on the density of states (DOS) near the maximum
\rho(r,t) which is the amount of time spent by the process at a distance r from
the maximum. We develop a path integral approach to study functionals of the
maximum of BM, which allows us to study the full probability density function
(PDF) of \rho(r,t) and obtain an explicit expression for the moments, \langle
[\rho(r,t)]^k \rangle, for arbitrary integer k. We also study near-extremes of
constrained BM, like the Brownian bridge. Finally we also present numerical
simulations to check our analytical results.


title:
L\'evy processes with marked jumps II : Application to a population
  model with mutations at birth

abstract:
  Consider a population where individuals give birth at constant rate during
their lifetimes to i.i.d. copies of themselves. Individuals bear clonally
inherited types, but (neutral) mutations may happen at the birth events. The
smallest subtree containing the genealogy of all the extant individuals at a
fixed time \tau, is called the coalescent point process. We enrich this process
with the history of the mutations that appeared over time, and call it the
marked coalescent point process. With the help of limit theorems for L\'evy
processes with marked jumps established in a previous work (arXiv:1305.6245),
we prove the convergence of the marked coalescent point process with large
population size and two possible regimes for the mutations - one of them being
a classical rare mutation regime, towards a multivariate Poisson point process.
This Poisson point process can be described as the coalescent point process of
the limiting population at \tau, with mutations arising as inhomogeneous
regenerative sets along the lineages. Its intensity measure is further
characterized thanks to the excursion theory for spectrally positive L\'evy
processes. In the rare mutations asymptotic, mutations arise as the image of a
Poisson process by the ladder height process of a L\'evy process with infinite
variation, and in the particular case of the critical branching process with
exponential lifetimes, the limiting object is the Poisson point process of the
depths of excursions of the Brownian motion, with Poissonian mutations on the
lineages.


title: Twisted Witt Groups of Flag Varieties

abstract:
  Calm\`es and Fasel have shown that the twisted Witt groups of split flag
varieties vanish in a large number of cases. For flag varieties over
algebraically closed fields, we sharpen their result to an if-and-only-if
statement. In particular, we show that the twisted Witt groups vanish in many
previously unknown cases. In the non-zero cases, we find that the twisted total
Witt group forms a free module of rank one over the untwisted total Witt group,
up to a difference in grading.
  Our proof relies on an identification of the Witt groups of flag varieties
with the Tate cohomology groups of their K-groups, whereby the verification of
all assertions is eventually reduced to the computation of the (twisted) Tate
cohomology of the representation ring of a parabolic subgroup.


title: Tissus alg\'ebriques exceptionnels

abstract:
  In arXiv:1302.3142, it has been proved that for r>1, n>1 and d>(r+1)(n-1)+1,
a d-web of type (r,n) with maximal rank is algebraizable in the classical
sense, except maybe when n>2 and d = (r+2)(n-1)+1. In the present paper, one
considers this particular case. Under these hypotheses on r, n and d, one
constructs some examples of `exceptional algebraic webs': these are generalized
algebraic webs of maximal rank that aren't algebraizable in the classical
sense.


title:
The quest for companions to post-common envelope binaries IV: The 2:1
  mean-motion resonance of the planets orbiting NN Serpentis

abstract:
  We present 69 new mid-eclipse times of the young post-common envelope binary
(PCEB) NN Ser, which was previously suggested to possess two circumbinary
planets. We have interpreted the observed eclipse-time variations in terms of
the light-travel time effect caused by two planets, exhaustively covering the
multi-dimensional parameter space by fits in the two binary and ten orbital
parameters. We supplemented the fits by stability calculations for all models
with an acceptable chi-square. An island of secularly stable 2:1 resonant
solutions exists, which coincides with the global chi-square minimum. Our
best-fit stable solution yields current orbital periods P_o = 15.47 yr and P_i
= 7.65 yr and eccentricities e_o = 0.14 and e_i = 0.22 for the outer (o) and
inner (i) planets, respectively. The companions qualify as giant planets, with
masses of 7.0 M_Jup and 1.7 M_Jup for the case of orbits coplanar with that of
the binary. The two-planet model that starts from the present system parameters
has a lifetime greater than 10^8 yr, which significantly exceeds the age of NN
Ser of 10^6 yr as a PCEB. The resonance is characterized by libration of the
resonant variable Theta_1 and circulation of omega_i-omega_o, the difference
between the arguments of periapse of the two planets. No stable non-resonant
solutions were found, and the possibility of a 5:2 resonance suggested
previously by us is now excluded at the 99.3% confidence level.


title: Spin-charge disparity of polarons in organic ferromagnets

abstract:
  Polaron formation in quasi-one-dimensional organic ferromagnets is studied
based on an extended Su-Schrieffer-Heeger model combined with a Kondo term. The
charge distribution of the polaron is found to be highly asymmetric under
spatial reflection, due to the spin radicals. On the contrary, the spin density
is nearly symmetric; the spin asymmetry introduced by the extra electron
inducing the polaron formation is nearly compensated by the spin polarization
of the lower-energy states. We discuss these results on the basis of real-space
mean-field calculations and symmetry arguments.


title: Collinear and non-collinear spin ground state of wurtzite CoO

abstract:
  Collinear and non-collinear spin structures of wurtzite phase CoO often
appearing in nano-sized samples are investigated using first-principles density
functional theory calculations. We examined the total energy of several
different spin configurations, electronic structure and the effective magnetic
coupling strengths. It is shown that the AF3-type antiferromagnetic ordering is
energetically most stable among possible collinear configurations. Further, we
found that a novel spiral spin order can be stabilized by including the
relativistic spin-orbit coupling and the non-collinearity of spin direction.
Our result suggests that a non-collinear spin ground state can be observed in
the transition-metal-oxide nanostructures which adds an interesting new aspect
to the nano-magnetism study.


title: User Guide for the Discrete Dipole Approximation Code DDSCAT 7.3

abstract:
  DDSCAT 7.3 is an open-source Fortran-90 software package applying the
discrete dipole approximation to calculate scattering and absorption of
electromagnetic waves by targets with arbitrary geometries and complex
refractive index. The targets may be isolated entities (e.g., dust particles),
but may also be 1-d or 2-d periodic arrays of "target unit cells", allowing
calculation of absorption, scattering, and electric fields around arrays of
nanostructures.
  The theory of the DDA and its implementation in DDSCAT is presented in Draine
(1988) and Draine & Flatau (1994), and its extension to periodic structures in
Draine & Flatau (2008), and efficient near-field calculations in Flatau &
Draine (2012). DDSCAT 7.3 includes support for MPI, OpenMP, and the Intel Math
Kernel Library (MKL). DDSCAT supports calculations for a variety of target
geometries. Target materials may be both inhomogeneous and anisotropic. It is
straightforward for the user to "import" arbitrary target geometries into the
code. DDSCAT automatically calculates total cross sections for absorption and
scattering and selected elements of the Mueller scattering intensity matrix for
user-specified scattering directions. DDSCAT 7.3 can efficiently calculate E
and B throughout a user-specified volume containing the target.
  This User Guide explains how to use DDSCAT 7.3 to carry out electromagnetic
scattering calculations, including use of DDPOSTPROCESS, a Fortran-90 code to
perform calculations with E and B at user-selected locations near the target. A
number of changes have been made since the last release, DDSCAT 7.2 .

categories: physics.comp-ph astro-ph.GA cond-mat.mes-hall physics.optics