title:
Integrable Boundary for Quad-Graph Systems: Three-Dimensional Boundary
  Consistency

abstract:
  We propose the notion of integrable boundary in the context of discrete
integrable systems on quad-graphs. The equation characterizing the boundary
must satisfy a compatibility equation with the one characterizing the bulk that
we called the three-dimensional (3D) boundary consistency. In comparison to the
usual 3D consistency condition which is linked to a cube, our 3D boundary
consistency condition lives on a half of a rhombic dodecahedron. The We provide
a list of integrable boundaries associated to each quad-graph equation of the
classification obtained by Adler, Bobenko and Suris. Then, the use of the term
"integrable boundary" is justified by the facts that there are B\"acklund
transformations and a zero curvature representation for systems with boundary
satisfying our condition. We discuss the three-leg form of boundary equations,
obtain associated discrete Toda-type models with boundary and recover previous
results as particular cases. Finally, the connection between the 3D boundary
consistency and the set-theoretical reflection equation is established.


title: On signed measure valued solutions of stochastic evolution equations

abstract:
  We study existence, uniqueness and mass conservation of signed measure valued
solutions of a class of stochastic evolution equations with respect to the
Wiener sheet, including as particular cases the stochastic versions of the
regularized two-dimensional Navier-Stokes equations in vorticity form
introduced by Kotelenez.


title:
Mass predictions of superheavy nuclei from the systematics of
  $\alpha$-Decay Energies

abstract:
  A recent proposed method for $\alpha$-decay energies ($Q_\alpha$) [J.M. Dong,
W. Zuo, and W. Scheid, Phys. Rev. Lett. \textbf{107}, 012501 (2011)] can
reproduce experimental data of superheavy nuclei (SHN) with an $rms$-value of
less than 100 keV. However, a sinusoid-like periodic deviation from
experiments, which limits the accuracy in predictions, is observed when using
different reference nuclei. In this paper, we have further extended this hybrid
method, i.e., to predict $Q_\alpha$ of the as-yet-unobserved SHN with the help
of known nuclei. It is found that the systematic deviation in previous study is
rooted in the nuclear mass model employed. By further analyzing the source of
errors, different nuclear mass models are evaluated based on the same
procedure.


title: Zero sound in a two-dimensional dipolar Fermi gas

abstract:
  We study zero sound in a weakly interacting 2D gas of single-component
fermionic dipoles (polar molecules or atoms with a large magnetic moment)
tilted with respect to the plane of their translational motion. It is shown
that the propagation of zero sound is provided by both mean field and many-body
(beyond mean field) effects, and the anisotropy of the sound velocity is the
same as the one of the Fermi velocity. The damping of zero sound modes can be
much slower than that of quasiparticle excitations of the same energy. One thus
has wide possibilities for the observation of zero sound modes in experiments
with 2D fermionic dipoles, although the zero sound peak in the structure
function is very close to the particle-hole continuum.


title:
Spectral distribution of large-size Brownian motions on the complex
  linear group

abstract:
  We show how the approach used in `N. Demni, T. Hmidi. Spectral Distribution
of the Free unitary Brownian motion: another approach. Sem. Probab. XLIV. 2012.
191-206.' applies to describe the large-size limit of the marginal distribution
of the Brownian motion on the complex linear group.


title: Quantum semigroup structures on quantum families of maps

abstract:
  These are notes accompanying lectures at 7th ILJU School of Mathematics
"Banach Spaces and Related Topics" in Gyeongju, Koera. The lectures are devoted
to exposition of the theory of quantum families of maps with emphasis on the
study of quantum semigroup structures appearing in this context.


title: Toric fiber products versus Segre products

abstract:
  The toric fiber product is an operation that combines two ideals that are
homogeneous with respect to a grading by an affine monoid. The Segre product is
a related construction that combines two multigraded rings. The quotient ring
by a toric fiber product of two ideals is a subring of the Segre product, but
in general this inclusion is strict. We contrast the two constructions and show
that any Segre product can be presented as a toric fiber product without
changing the involved quotient rings. This allows to apply previous results
about toric fiber products to the study of Segre products.
  We give criteria for the Segre product of two affine toric varieties to be
dense in their toric fiber product, and for the map from the Segre product to
the toric fiber product to be finite. We give an example that shows that the
quotient ring of a toric fiber product of normal ideals need not be normal. In
rings with Veronese type gradings, we find examples of toric fiber products
that are always Segre products, and we show that iterated toric fiber products
of Veronese ideals over Veronese rings are normal.


title:
Causality-Driven Slow-Down and Speed-Up of Diffusion in Non-Markovian
  Temporal Networks

abstract:
  Recent research has highlighted limitations of studying complex systems with
time-varying topologies from the perspective of static, time-aggregated
networks. Non-Markovian characteristics resulting from the ordering of
interactions in temporal networks were identified as one important mechanism
that alters causality, and affects dynamical processes. So far, an analytical
explanation for this phenomenon and for the significant variations observed
across different systems is missing. Here we introduce a methodology that
allows to analytically predict causality-driven changes of diffusion speed in
non-Markovian temporal networks. Validating our predictions in six data sets,
we show that - compared to the time-aggregated network - non-Markovian
characteristics can lead to both a slow-down, or speed-up of diffusion which
can even outweigh the decelerating effect of community structures in the static
topology. Thus, non-Markovian properties of temporal networks constitute an
important additional dimension of complexity in time-varying complex systems.

categories: physics.soc-ph cond-mat.dis-nn cond-mat.stat-mech cs.SI


title:
Solution of the Gross-Pitaevskii equation in terms of the associated
  non-linear Hartree potential

abstract:
  The Gross-Pitaevskii equation (GP), that describes the wave function of a
number of coherent Bose particles contained in a trap, contains the cube of the
normalized wave function, times a factor proportional to the number of coherent
atoms. The square of the wave function, times the above mentioned factor, is
defined as the Hartree potential. A method implemented here for the numerical
solution of the GP equation consists in obtaining the Hartree potential
iteratively, starting with the Thomas Fermi approximation to this potential.
The energy eigenvalues and the corresponding wave functions for each successive
potential are obtained by a method described previously. After approximately 35
iterations a stability of eight significant figures for the energy eigenvalues
is obtained.This method has the advantage of being physically intuitive, and
could be extended to the calculation of a shell-model potential in nuclear
physics, once the Pauli exclusion principle is allowed for.


title: Birational morphisms and Poisson moduli spaces

abstract:
  We study birational morphisms between smooth projective surfaces that respect
a given Poisson structure, with particular attention to induced birational maps
between the (Poisson) moduli spaces of sheaves on those surfaces. In
particular, to any birational morphism, we associate a corresponding "minimal
lift" operation on sheaves of homological dimension <=1, and study its
properties. In particular, we show that minimal lift induces a stratification
of the moduli space of simple sheaves on the codomain by open subspaces of the
moduli space of simple sheaves on the domain, compatibly with the induced
Poisson structures.


title: Generalized Hitchin systems on rational surfaces

abstract:
  By analogy with work of Hitchin on integrable systems, we construct natural
relaxations of several kinds of moduli spaces of difference equations, with
special attention to a particular class of difference equations on an elliptic
curve (arising in the theory of elliptic special functions). The common feature
of the relaxations is that they can be identified with moduli spaces of sheaves
on rational surfaces. Not only does this make various natural questions become
purely geometric (rigid equations correspond to -2-curves), it also establishes
a number of nontrivial correspondences between different moduli spaces, since a
given moduli space of sheaves is typically the relaxation of infinitely many
moduli spaces of equations. In the process of understanding this, we also
consider a number of purely geometric questions about rational surfaces with
anticanonical curves; e.g., we give an essentially combinatorial algorithm for
testing whether a given divisor is the class of a -2-curve or is effective with
generically integral representative.


title:
Local existence and uniqueness for a two-dimensional surface growth
  equation with space--time white noise

abstract:
  We study local existence and uniqueness for a surface growth model with
space-time white noise in 2D. Unfortunately, the direct fixed-point argument
for mild solutions fails here, as we do not have sufficient regularity for the
stochastic forcing. Nevertheless, one can give a rigorous meaning to the
stochastic PDE and show uniqueness of solutions in that setting. Using spectral
Galerkin method and any other types of regularization of the noise, we obtain
always the same solution.


title: Majority Dynamics and the Retention of Information

abstract:
  We consider a group of agents connected by a social network who participate
in majority dynamics: each agent starts with an opinion in {-1,+1} and
repeatedly updates it to match the opinion of the majority of its neighbors.
  We assume that one of {-1,+1} is the "correct" opinion S, and consider a
setting in which the initial opinions are independent conditioned on S, and
biased towards it. They hence contain enough information to reconstruct S with
high probability. We ask whether it is still possible to reconstruct S from the
agents' opinions after many rounds of updates.
  While this is not the case in general, we show that indeed, for a large
family of bounded degree graphs, information on S is retained by the process of
majority dynamics.
  Our proof technique yields novel combinatorial results on majority dynamics
on both finite and infinite graphs, with applications to zero temperature Ising
models.


title: Population Dynamics with Infinite Leslie Matrices

abstract:
  Infinite Leslie matrices, introduced by Demetrius forty years ago are
mathematical models of age-structured populations defined by a countable
infinite number of age classes. This article is concerned with determining
solutions of the discrete dynamical system in finite time. We address this
problem by appealing to the concept of kneading matrices and kneading
determinants. Our analysis is applicable not only to populations models, but to
models of self-reproducing machines and self-reproducing computer programs. The
dynamics of theses systems can also be described in terms of infinite Leslie
matrices.uation.


title:
KK MC 4.22: CEEX EW Corrections for f\bar{f}\rightarrow f'\bar{f'} at
  LHC and Muon Colliders

abstract:
  We present the upgrade of the coherent exclusive (CEEX) exponentiation
realization of the Yennie-Frautschi-Suura (YFS) theory used in our Monte Carlo
({\cal KK} MC) to the processes f\bar{f}\rightarrow f'\bar{f'},
f=\mu,\tau,q,\nu_\ell, f'=e,\mu,\tau,q,\nu_\ell, q=u,d,s,c,b,t, \ell=e,\mu,\tau
with f\ne f', with an eye toward the precision physics of the LHC and possible
high energy muon colliders. We give a brief summary of the CEEX theory in
comparison to the older (EEX) exclusive exponentiation theory and illustrate
theoretical results relevant to the LHC and possible muon collider physics
programs.


title: An alternative Gospel of structure: order, composition, processes

abstract:
  We survey some basic mathematical structures, which arguably are more
primitive than the structures taught at school. These structures are orders,
with or without composition, and (symmetric) monoidal categories. We list
several `real life' incarnations of each of these. This paper also serves as an
introduction to these structures and their current and potentially future uses
in linguistics, physics and knowledge representation.


title: Time Constants of Spin-Dependent Recombination Processes

abstract:
  We present experiments to systematically study the time constants of
spin-dependent recombination processes in semiconductors using pulsed
electrically detected magnetic resonance (EDMR). The combination of
time-programmed optical excitation and pulsed spin manipulation allows us to
directly measure the recombination time constants of electrons via localized
spin pairs and the time constant of spin pair formation as a function of the
optical excitation intensity. Using electron nuclear double resonance, we show
that the time constant of spin pair formation is determined by an electron
capture process. Based on these time constants we devise a set of rate
equations to calculate the current transient after a resonant microwave pulse
and compare the results with experimental data. Finally, we critically discuss
the effects of different boxcar integration time intervals typically used to
analyze pulsed EDMR experiments on the determination of the time constants. The
experiments are performed on phosphorus-doped silicon, where EDMR via spin
pairs formed by phosphorus donors and Si/SiO2 interface dangling bond defects
is detected.


title: The distribution of the electric current in a watt-balance coil

abstract:
  In the watt balance experiments, separate measurements of the magnetic and
electromotive forces in a coil in a magnetic field enable a virtual comparison
between mechanical and electric powers to be carried out, which lead to an
accurate measurement of the Planck constant. This paper investigates the
three-dimensional nature of the coil-field interaction and describes the
balance operation by a continuous three-dimensional model.


title: The essential skeleton of a degeneration of algebraic varieties

abstract:
  In this paper, we explore the connections between the Minimal Model Program
and the theory of Berkovich spaces. Let $k$ be a field of characteristic zero
and let $X$ be a smooth and proper $k((t))$-variety with semi-ample canonical
divisor. We prove that the essential skeleton of $X$ coincides with the
skeleton of any minimal $dlt$-model and that it is a strong deformation retract
of the Berkovich analytification of $X$. As an application, we show that the
essential skeleton of a Calabi-Yau variety over $k((t))$ is a pseudo-manifold.


title: Binary collision approximation for multi-decorated granular chains

abstract:
  We study pulse propagation along decorated tapered granular chains without
precompression. Our goal is to generalize the results obtained in our previous
work, by analyzing a decorated chain with an arbitrary number of small grains
between the large ones. Making use of an effective description, where the
original decorated tapered chain is replaced by a non-decorated tapered chain
with effective masses interacting via an effective potential, and applying the
binary collisions approximation, we calculate the residence time of the pulse
on each effective large grain. We also present the comparison between the
numerical integration of the equations of motion and our analytical predictions
which show the agreement to be very good for the pulse velocity, albeit only
qualitatively for the velocity of the grains.


title: UHECR: Signatures and Models

abstract:
  The signatures of Ultra High Energy (E >1 EeV) proton propagation through CMB
radiation are pair-production dip and GZK cutoff. The visible characteristics
of these two spectral features are ankle, which is intrinsic part of the dip,
beginning of GZK cutoff in the differential spectrum and E_{1/2} in integral
spectrum. Measured by HiRes and Telescope Array (TA) these characteristics
agree with theoretical predictions. However, directly measured mass composition
remains a puzzle. While HiRes and TA detectors observe the proton dominated
mass composition, the data of Auger detector strongly evidence for nuclei mass
composition becoming progressively heavier at energy higher than 4 EeV and
reaching Iron at energy about 35 EeV. The models based on the Auger and
HiRes/TA data are considered independently and classified using the transition
from galactic to extragalactic cosmic rays. The ankle cannot provide this
transition. since data of all three detector at energy (1 - 3) EeV agree with
pure proton composition (or at least not heavier than Helium). If produced in
Galaxy these particles result in too high anisotropy. This argument excludes or
strongly disfavours all ankle models with ankle energy E_a > 3 EeV. The
calculation of elongation curves, X_{\max}(E), for different ankle models
strengthens further this conclusion. Status of other models, the dip, mixed
composition and Auger based models are discussed.


title:
Relevance of various Dirac covariants in hadronic Bethe-Salpeter wave
  functions in electromagnetic decays of ground state vector mesons

abstract:
  In this work we have employed Bethe-Salpeter equation (BSE) under covariant
instantaneous ansatz (CIA) to study electromagnetic decays of ground state
equal mass vector mesons: $\rho$, $\omega$, $\phi$, $\psi$ and $Y$ through the
process $V\rightarrow\gamma*\rightarrow e^+ + e^-$. We employ the generalized
structure of hadron-quark vertex function $\Gamma$ which incorporates various
Dirac structures from their complete set order-by-order in powers of inverse of
meson mass. The electromagnetic decay constants for the above mesons are
calculated using the leading order (LO) and the next-to-leading order (NLO)
Dirac structures. The relevance of various Dirac structures in this calculation
is studied.


title:
Comparison of volume-selective z-shim and conventional EPI in fMRI
  studies using face stimuli

abstract:
  Single-shot gradient recalled echo planar imaging (EPI) is the primary tool
for functional magnetic resonance imaging (fMRI). The image often suffers from
signal drop near the air-tissue interface, such as the amygdala and regions of
the orbitofrontal lobe. An effective way to correct for this type of artifact
is by applying multi-shot EPI using different z-shimming. Unfortunately, the
scanning efficiency is significantly lowered. More recently, a new technique
called volume-selective z-shim was proposed to implement z-shim compensation to
only specific slices with large susceptibility effects. The high imaging
efficiency of volume selective z-shim makes it possible to substitute
conventional EPI for whole brain studies. In this study two fMRI experiments
were conducted to compare volume- selective z-shim and conventional EPI while
subjects performed tasks on face stimuli. The comparison was focused on three
brain regions: amygdala, hippocampus, and fusiform gyrus. Our results indicate
that despite fewer volumes collected during the same amount of scan time,
volume-selective z-shim showed statistically higher activation in brain regions
susceptible to signal loss while minimal differences were observed elsewhere.


title:
PeerShare: A System Secure Distribution of Sensitive Data Among Social
  Contacts

abstract:
  We present the design and implementation of the PeerShare, a system that can
be used by applications to securely distribute sensitive data to social
contacts of a user. PeerShare incorporates a generic framework that allows
different applications to distribute data with different security requirements.
By using interfaces available from existing popular social networks. PeerShare
is designed to be easy to use for both end users as well as developers of
applications. PeerShare can be used to distribute shared keys, public keys and
any other data that need to be distributed with authenticity and
confidentiality guarantees to an authorized set of recipients, specified in
terms of social relationships. We have used \peershare already in three
different applications and plan to make it available for developers.


title:
Convex relaxation for finding planted influential nodes in a social
  network

abstract:
  We consider the problem of maximizing influence in a social network. We focus
on the case that the social network is a directed bipartite graph whose arcs
join senders to receivers. We consider both the case of deterministic networks
and probabilistic graphical models, that is, the so-called "cascade" model. The
problem is to find the set of the $k$ most influential senders for a given
integer $k$. Although this problem is NP-hard, there is a polynomial-time
approximation algorithm due to Kempe, Kleinberg and Tardos. In this work we
consider convex relaxation for the problem. We prove that convex optimization
can recover the exact optimizer in the case that the network is constructed
according to a generative model in which influential nodes are planted but then
obscured with noise. We also demonstrate computationally that the convex
relaxation can succeed on a more realistic generative model called the "forest
fire" model.


title:
Modified SPLICE and its Extension to Non-Stereo Data for Noise Robust
  Speech Recognition

abstract:
  In this paper, a modification to the training process of the popular SPLICE
algorithm has been proposed for noise robust speech recognition. The
modification is based on feature correlations, and enables this stereo-based
algorithm to improve the performance in all noise conditions, especially in
unseen cases. Further, the modified framework is extended to work for
non-stereo datasets where clean and noisy training utterances, but not stereo
counterparts, are required. Finally, an MLLR-based computationally efficient
run-time noise adaptation method in SPLICE framework has been proposed. The
modified SPLICE shows 8.6% absolute improvement over SPLICE in Test C of
Aurora-2 database, and 2.93% overall. Non-stereo method shows 10.37% and 6.93%
absolute improvements over Aurora-2 and Aurora-4 baseline models respectively.
Run-time adaptation shows 9.89% absolute improvement in modified framework as
compared to SPLICE for Test C, and 4.96% overall w.r.t. standard MLLR
adaptation on HMMs.


title: Heterotic Flux Geometry from Chiral Gauge Dynamics

abstract:
  Chiral gauge theories in two dimensions with (0,2) supersymmetry admit a much
broader, and more interesting, class of vacuum solutions than their better
studied (2,2) counterparts. In this thesis, we will explore some of the
possibilities that are offered by this additional freedom by including
field-dependent theta-angles and FI parameters. The moduli spaces that will
result from this procedure correspond to heterotic string backgrounds with
non-trivial H-flux and NS-brane sources. Along the way, a remarkable
relationship between (0,2) gauge anomalies and H-flux will emerge.


title:
Detection techniques for the H.E.S.S. II telescope, data modeling of
  gravitational lensing and emission of blazars in HE-VHE astronomy

abstract:
  This thesis presents the study of four aspects of high energy astronomy. The
first part of the thesis is dedicated to an aspect of instrument development
for imaging atmospheric Cherenkov telescopes, namely the Level 2 trigger system
of the High Energy Stereoscopic System (H.E.S.S.). I am providing the
motivation and principle of the operation of the Level 2 trigger, I am
describing hardware implementation of the system and then I am evaluating
expected performances. The second part of my thesis deals with the data
analysis and modeling of broad-band emission of particular blazar PKS 1510-089.
I am presenting the analysis of the H.E.S.S. data, together with the FERMI data
and a collection of multi-wavelength data obtained with various instruments. I
am presenting the model of PKS 1510-089 observations carried out during a flare
recorded by H.E.S.S.. The third part of my thesis deals with blazars observed
by the FERMI-LAT, but from the point of view of other phenomena: a strong
gravitational lensing. This part of my thesis shows the first evidence for
gravitational lensing phenomena in high energy gamma-rays. This evidence comes
from the observation of a gravitational lens system induced echo in the light
curve of the distant blazar PKS 1830-211. The last part concentrates on another
lensing phenomena called femtolensing. The search for femtolensing effects has
been used to derive limits on the primordial black holes abundance. I have used
gamma-ray bursts with known redshifts detected by the FERMI Gamma-ray Burst
Monitor (GBM) to search for the femtolensing effects caused by compact objects.


title: Higgs form factors in Associated Production

abstract:
  We further develop a form factor formalism characterizing anomalous
interactions of the Higgs-like boson (h) to massive electroweak vector bosons
(V) and generic bilinear fermion states (F). Employing this approach, we
examine the sensitivity of pp -> F ->Vh associated production to physics beyond
the Standard Model, and compare it to the corresponding sensitivity of h -> V F
decays. We discuss how determining the Vh invariant-mass distribution in
associated production at LHC is a key ingredient for model-independent
determinations of h V F interactions. We also provide a general discussion
about the power counting of the form factor's momentum dependence in a generic
effective field theory approach, analyzing in particular how effective theories
based on a linear and non-linear realization of the SU(2)_L x U(1)_Y gauge
symmetry map into the form factor formalism. We point out how measurements of
the differential spectra characterizing h -> V F decays and pp -> F -> Vh
associated production could be the leading indication of the presence of a
nonlinear realization of the SU(2)_L x U(1)_Y gauge symmetry.


title: Aspects of the inverse problem for the Toda chain

abstract:
  We generalize Babelon's approach to equations in dual variables so as to be
able to treat new types of operators which we build out of the sub-constituents
of the model's monodromy matrix. Further, we also apply Sklyanin's recent
monodromy matrix identities so as to obtain equations in dual variables for yet
other operators. The schemes discussed in this paper appear to be universal and
thus, in principle, applicable to many models solvable through the quantum
separation of variables.


title: Hardcore bosons in a zig-zag optical superlattice

abstract:
  We study a system of hard-core bosons at half-filling in a one-dimensional
optical superlattice. The bosons are allowed to hop to nearest and next-nearest
neighbor sites producing a zig-zag geometry and we obtain the ground state
phase diagram as a function of microscopic parameters using the finite-size
density matrix renormalization group (FS-DMRG) method. Depending on the sign of
the next-nearest neighbor hopping and the strength of the superlattice
potential the system exhibits three different phases, namely the bond-order
(BO) solid, the superlattice induced Mott insulator (SLMI) and the superfluid
(SF) phase. When the signs of both hopping amplitudes are the same (the
"unfrustrated" case), the system undergoes a transition from the SF to the SLMI
at a non-zero value of the superlattice potential. On the other hand, when the
two amplitudes differ in sign (the "frustrated" case), the SF is unstable to
switching on a superlattice potential and also exists only up to a finite value
of the next nearest neighbor hopping. This part of the phase diagram is
dominated by the BO phase which breaks translation symmetry spontaneously even
in the absence of the superlattice potential and can thus be characterized by a
bond order parameter. The transition from BO to SLMI appears to be first order.


title: Pairing and specific heat in hot nuclei

abstract:
  The thermodynamics of pairing phase-transition in nuclei is studied in the
canonical ensemble and treating the pairing correlations in a
finite-temperature variation after projection BCS approach (FT-VAP). Due to the
restoration of particle number conservation, the pairing gap and the specific
heat calculated in the FT-VAP approach vary smoothly with the temperature,
indicating a gradual transition from the superfluid to the normal phase, as
expected in finite systems. We have checked that the predictions of the FT-VAP
approach are very accurate when compared to the results obtained by an exact
diagonalization of the pairing Hamiltonian. The influence of pairing
correlations on specific heat is analysed for the isotopes $^{161,162}$Dy and
$^{171,172}$Yb. It is shown that the FT-VAP approach, applied with a level
density provided by mean field calculations and supplemented, at high energies,
by the level density of the back-shifted Fermi gas model, can approximate
reasonably well the main properties of specific heat extracted from
experimental data. However, the detailed shape of the calculated specific heat
is rather sensitive to the assumption made for the mean field.


title: Renormalization of Nielsen Identities

abstract:
  We study renormalization of identities governing the dependence of 1PI
Green's functions on gauge-fixing parameters. For general dimensionally
regularized Yang-Mills theories with gauge groups being direct products of
arbitrary compact simple Lie groups and U(1) groups coupled to scalar fields,
we extend the well known analysis in Fermi gauges to the class of generalized
't Hoot gauges $R_{\xi,u}$, in which also symmetry under global gauge
transformations is broken by the gauge-fixing procedure. We also discuss
conditions ensuring homogeneity of the Nielsen identity satisfied by the
effective potential.


title:
Inverse Bernstein inequalities and min-max-min problems on the unit
  circle

abstract:
  We give a short and elementary proof of an inverse Bernstein-type inequality
found by S. Khrushchev for the derivative of a polynomial having all its zeros
on the unit circle. The inequality is used to show that equally-spaced points
solve a min-max-min problem for the logarithmic potential of such polynomials.
Using techniques recently developed for polarization (Chebyshev-type) problems,
we show that this optimality also holds for a large class of potentials,
including the Riesz potentials $1/r^s$ with $s>0.$


title: Towards the Test of Saturation Physics Beyond Leading Logarithm

abstract:
  We present results from the first next-to-leading order (NLO) numerical
analysis of forward hadron production in pA collisions in the small-x
saturation formalism. Using parton distributions and fragmentation functions at
NLO, as well as the dipole amplitude from the solution to the
Balitsky-Kovchegov equation with running coupling, together with the NLO
corrections to the hard coefficients, we obtain a good description of the
available RHIC data in dAu collisions. We also comment on the results in the
large p_T region beyond the saturation scale. Furthermore, we make predictions
for forward hadron production in pPb collisions at the LHC. This analysis not
only incorporates the important NLO corrections for all partonic channels, but
also reduces the renormalization scale dependence and therefore helps to
significantly reduce the theoretical uncertainties. It therefore provides a
precise test of saturation physics beyond the leading logarithmic
approximation.


title:
The Influence of Spatial Variation in Chromatin Density Determined by
  X-ray Tomograms on the Time to Find DNA Binding Sites

abstract:
  In this work we examine how volume exclusion caused by regions of high
chromatin density might influence the time required for proteins to find
specific DNA binding sites. The spatial variation of chromatin density within
mouse olfactory sensory neurons is determined from soft X-ray tomography
reconstructions of five nuclei. We show that there is a division of the nuclear
space into regions of low-density euchromatin and high-density heterochromatin.
Volume exclusion experienced by a diffusing protein caused by this varying
density of chromatin is modeled by a repulsive potential. The value of the
potential at a given point in space is chosen to be proportional to the density
of chromatin at that location. The constant of proportionality, called the
volume exclusivity, provides a model parameter that determines the strength of
volume exclusion. Numerical simulations demonstrate that the mean time for a
protein to locate a binding site localized in euchromatin is minimized for a
finite, non-zero volume exclusivity. For binding sites in heterochromatin, the
mean time is minimized when the volume exclusivity is zero (the protein
experiences no volume exclusion). An analytical theory is developed to explain
these results. The theory suggests that for binding sites in euchromatin there
is an optimal level of volume exclusivity that balances a reduction in the
volume searched in finding the binding site, with the height of effective
potential barriers the protein must cross during the search process.


title: Higher discriminants and the topology of algebraic maps

abstract:
  We show that the way in which Betti cohomology varies in a proper family of
complex algebraic varieties is controlled by certain "higher discriminants" in
the base. These discriminants are defined in terms of transversality
conditions, which in the case of a morphism between smooth varieties can be
checked by a tangent space calculation. They control the variation of
cohomology in the following two senses: (1) the support of any summand of the
pushforward of the IC sheaf along a projective map is a component of a higher
discriminant, and (2) any component of the characteristic cycle of the proper
pushforward of the constant function is a conormal variety to a component of a
higher discriminant.
  The same would hold for the Whitney stratification of the family, but there
are vastly fewer higher discriminants than Whitney strata. For example, in the
case of the Hitchin fibration, the stratification by higher discriminants gives
exactly the {\delta} stratification introduced by Ngo.


title:
Transport of a Bose gas in 1D disordered lattices at the fluid-insulator
  transition

abstract:
  We investigate the momentum-dependent transport of 1D quasi-condensates in
quasiperiodic optical lattices. We observe a sharp crossover from a weakly
dissipative regime to a strongly unstable one at a disorder-dependent critical
momentum. In the limit of non-disordered lattices the observations indicate a
contribution of quantum phase slips to the dissipation. We identify a set of
critical disorder and interaction strengths for which such critical momentum
vanishes, separating a fluid regime from an insulating one. We relate our
observation to the predicted zero-temperature superfluid-Bose glass transition.


title:
Melting curve of face-centred-cubic nickel from first principles
  calculations

abstract:
  The melting curve of Ni up to 100 GPa has been calculated using first
principles methods based on density functional theory (DFT). We used two
complementary approaches: i) coexistence simulations with a reference system
and then free energy corrections between DFT and the reference system, and ii)
direct DFT coexistence using simulation cells including 1000 atoms. The
calculated zero pressure melting temperature is slightly underestimated at
$1637 \pm 10$ K (experimental value is 1728 K), and at high pressure is
significantly higher than recent measurements in diamond anvil cell experiments
[Phys. Rev. B {\bf 87}, 054108 (2013)]. The zero pressure DFT melting slope is
calculated to be $30 \pm 2$ K, in good agreement with the experimental value of
28 K.


title:
Empirical Evidence of Large-Scale Diversity in API Usage of
  Object-Oriented Software

abstract:
  In this paper, we study how object-oriented classes are used across thousands
of software packages. We concentrate on "usage diversity'", defined as the
different statically observable combinations of methods called on the same
object. We present empirical evidence that there is a significant usage
diversity for many classes. For instance, we observe in our dataset that Java's
String is used in 2460 manners. We discuss the reasons of this observed
diversity and the consequences on software engineering knowledge and research.


title:
Reading the Correct History? Modeling Temporal Intention in Resource
  Sharing

abstract:
  The web is trapped in the "perpetual now", and when users traverse from page
to page, they are seeing the state of the web resource (i.e., the page) as it
exists at the time of the click and not necessarily at the time when the link
was made. Thus, a temporal discrepancy can arise between the resource at the
time the page author created a link to it and the time when a reader follows
the link. This is especially important in the context of social media: the ease
of sharing links in a tweet or Facebook post allows many people to author web
content, but the space constraints combined with poor awareness by authors
often prevents sufficient context from being generated to determine the intent
of the post. If the links are clicked as soon as they are shared, the temporal
distance between sharing and clicking is so small that there is little to no
difference in content. However, not all clicks occur immediately, and a delay
of days or even hours can result in reading something other than what the
author intended. We introduce the concept of a user's temporal intention upon
publishing a link in social media. We investigate the features that could be
extracted from the post, the linked resource, and the patterns of social
dissemination to model this user intention. Finally, we analyze the historical
integrity of the shared resources in social media across time. In other words,
how much is the knowledge of the author's intent beneficial in maintaining the
consistency of the story being told through social posts and in enriching the
archived content coverage and depth of vulnerable resources?


title: Self force from equivalent periodic sources

abstract:
  Considering the self force and radiation due to a small body in orbit
(especially aperiodic) around a black hole, this paper defines a decomposition
of the source into a sum over the shape preserving periodic motions of extended
objects defined here consisting of ensembles of freely falling point particles.
The stationary component is found to be within the conservative sector.
Self-force computation throughout a specified trajectory reduces to solving one
spatial partial differential equation (PDE) and a series of PDE's with periodic
time. Regularization is alleviated due to the sources' extended nature. A
regularization method is suggested inspired by the type present in
electrostatics with surface or other singular sources.


title: Consistency conditions from generalized-unitarity

abstract:
  In the modern on-shell approach, the perturbative S-matrix is constructed
iteratively using on-shell building blocks with manifest unitarity. As only
gauge invariant quantities enter in the intermediate steps, the notion of gauge
anomaly is absent. In this letter, we rephrase the anomaly cancellation
conditions in a purely on-shell language. We demonstrate that while the
unitarity-methods automatically lead to a unitary S-matrix, the rational terms
that are required to enforce locality, invariably give rise to inconsistent
factorization channels in chiral theories. In four-dimensions, the absence of
such inconsistencies implies the vanishing of the cubic Casimir of the gauge
group. In six-dimensions, if the symmetric trace of four generators does not
vanish, the rational term develops a factorization channel revealing a new
particle in the spectrum: the two-form of the Green-Schwarz mechanism. Thus in
the purely on-shell construction, the notion of gauge-anomaly is replaced by
the difficulty to consistently impose locality on the unitary S-matrix.


title:
Pre-slow roll initial conditions: large scale power suppression and
  infrared aspects during inflation

abstract:
  If the large scale anomalies in the temperature power spectrum of the cosmic
microwave background are of primordial origin, they may herald modifications to
the slow roll inflationary paradigm on the largest scales. We study the
possibility that the origin of the large scale power suppression is a
modification of initial conditions during slow roll as a result of a pre-slow
roll phase during which the inflaton evolves rapidly. This stage is manifest in
a potential in the equations for the Gaussian fluctuations during slow roll and
modify the power spectra of scalar perturbations via an initial condition
transfer function $\mathcal{T}(k)$. We provide a general analytical study of
its large and small scale properties and analyze the impact of these initial
conditions on the infrared aspects of typical test scalar fields. The infrared
behavior of massless minimally coupled test scalar field theories leads to the
dynamical generation of mass and anomalous dimensions, both depend
non-analytically on $\mathcal{T}(0)$. During inflation all quanta decay into
many quanta even of the same field because of the lack of kinematic thresholds.
The decay leads to a quantum entangled state of sub and superhorizon quanta
with correlations across the horizon. We find the modifications of the decay
width and the entanglement entropy from the initial conditions. In all cases,
initial conditions from a ``fast-roll'' stage that lead to a suppression in the
scalar power spectrum at large scales also result in a suppression of the
dynamically generated masses, anomalous dimensions and decay widths.


title: A Paneitz-type problem in pierced domains

abstract:
  We study the critical problem {equation} {{array}{ll} \Delta
^{2}u=u^{\frac{N+4}{N-4}} & {in}\Omega\setminus
\bar{B(\xi_0,\varepsilon)},\medskip u>0&{in}\Omega\setminus
\bar{B(\xi_0,\varepsilon)},\medskip u=\Delta u=0 & {on}\partial (\Omega
\setminus \bar{B(\xi_0,\varepsilon)}),{array}. \tag{P$_\varepsilon$} {equation}
where $\Omega$ is an open bounded domain in $\mathbb{R}^N$, $N\ge5$,
$\xi_0\in\Omega$ and $B(\xi_0,\varepsilon)$ is the ball centered at $\xi_0$
with radius $\varepsilon>0$ small enough. We construct solutions of
(P$_\varepsilon$) blowing-up at the center of the hole as the size of the hole
goes to zero.


title: Lorentz and CPT violation in the hydrogen spectrum

abstract:
  We have studied the effect of hypothetical violations of Lorentz and CPT
symmetry by calculating the corrections to the energy levels of hydrogen
induced by the Standard-Model Extension (SME). Hydrogen studies are interesting
because the energy levels of hydrogen can be measured with great precision and
the theory for hydrogen based on the Standard Model (SM) is well understood. We
obtained corrections through order \alpha^2 times the SME parameters for all
levels of hydrogen and applied them to determine the SME corrections to the
transition frequency for the 2S-1S transition.


title: Temperature Gated Thermal Rectifier

abstract:
  Heat flow control is essential for widespread applications of heating,
cooling, energy conversion and utilization. Here we demonstrate the first
observation of temperature-gated thermal rectification in vanadium dioxide
beams, in which an environment temperature actively modulates asymmetric heat
flow. In this three terminal device, there are two switchable states, which can
be accessed by global heating: Rectifier state and Resistor state. In the
Rectifier state, up to 28% thermal rectification is observed. In the Resistor
state, the thermal rectification is significantly suppressed (below 4%). This
temperature-gated rectifier can have substantial implications ranging from
autonomous thermal management of micro/nanoscale devices to thermal energy
conversion and storage.


title:
Phase diagram of strongly interacting matter under strong magnetic
  fields

abstract:
  The understanding of the behaviour of strongly interacting matter at finite
temperature and density is of fundamental interest and has applications in
cosmology, in the astrophysics of neutron stars and in the physics of
relativistic heavy ion collisions. Given the possible existence of strong
magnetic fields in the mentioned situations, their effect on the QCD phase
diagram has recently become a topic of increasing interest. Here, we report on
the study of this issue in the framework of the two flavor Nambu-Jona-Lasinio
model with Polyakov loop (PNJL) and an extension of it, the so-called entangled
PNJL model (EPNJL).


title:
Multispinon continua at zero and finite temperature in a near-ideal
  Heisenberg chain

abstract:
  The space- and time-dependent response of many-body quantum systems is the
most informative aspect of their emergent behaviour. The dynamical structure
factor, experimentally measurable using neutron scattering, can map this
response in wavevector and energy with great detail, allowing theories to be
quantitatively tested to high accuracy. Here, we present a comparison between
neutron scattering measurements on the one-dimensional spin-1/2 Heisenberg
antiferromagnet KCuF3, and recent state-of-the-art theoretical methods based on
integrability and density matrix renormalization group simulations. The
unprecedented quantitative agreement shows that precise descriptions of
strongly correlated states at all distance, time and temperature scales are now
possible, and highlights the need to apply these novel techniques to other
problems in low-dimensional magnetism.


title:
Schwarzschild-Couder telescope for the Cherenkov Telescope Array:
  Development of the Optical System

abstract:
  The CTA (Cherenkov Telescope Array) is the next generation ground-based
experiment for very high-energy (VHE) gamma-ray observations. It will integrate
several tens of imaging atmospheric Cherenkov telescopes (IACTs) with different
apertures into a single astronomical instrument. The US part of the CTA
collaboration has proposed and is developing a novel IACT design with a
Schwarzschild-Couder (SC) aplanatic two mirror optical system. In comparison
with the traditional single mirror Davies-Cotton IACT the SC telescope, by
design, can accommodate a wide field-of-view, with significantly improved
imaging resolution. In addition, the reduced plate scale of an SC telescope
makes it compatible with highly integrated cameras assembled from silicon photo
multipliers. In this submission we report on the status of the development of
the SC optical system, which is part of the effort to construct a full-scale
prototype telescope of this type at the Fred Lawrence Whipple Observatory in
southern Arizona.


title: A Note On Heisenberg Categorification

abstract:
  A categorification of the Heisenberg algebra is constructed in by Khovanov
using graphical calculus, and left with a conjecture on the isomorphism between
the Heisenberg algebra and Grothendieck ring of the constructed category. We
give a proof of Khovanov's conjectured statement in this paper from a
categorification of some deformed Heisenberg algebra.


title: Bilinear R Parity Violation at the ILC - Neutrino Physics at Colliders

abstract:
  Supersymmetry (SUSY) with bilinearly broken R parity (bRPV) offers an
attractive possibility to explain the origin of neutrino masses and mixings. In
such scenarios, the study of neutralino decays at colliders gives access to
neutrino sector parameters. The ILC offers a very clean environment to study
the neutralino properties as well as its subsequent decays, which typically
involve a $W$ or $Z$ boson and a lepton. This study is based on ILC beam
parameters according to the Technical Design Report for a center of mass energy
of $500\,\mathrm{GeV}$. A full detector simulation of the International Large
Detector (ILD) was performed for all Standard Model backgrounds and for
$\widetilde{\chi}_1^0$-pair production within a simplified model. The bRPV
parameters are fixed according to current neutrino data. In this scenario, the
$\widetilde{\chi}_1^0$ mass can be reconstructed with an uncertainty of $\delta
m = (40(\text{stat.}) + 50(\text{syst.}))\,\mathrm{MeV}$ for an integrated
luminosity of $500\,\mathrm{fb}^{-1}$ from direct $\widetilde{\chi}_1^0$-pair
production, thus, to a large extent independently of the rest of the SUSY
spectrum. The achievable precision on the atmospheric neutrino mixing angle
$\sin^2 \theta_{23}$ from measuring the neutralino branching fractions
$\mathrm{BR}(\widetilde{\chi}_1^0 \rightarrow W \mu)$ and
$\mathrm{BR}(\widetilde{\chi}_1^0 \rightarrow W \tau)$ at the ILC is better
than current uncertainties from neutrino experiments. Thus, the ILC could have
the opportunity to unveil the mechanism of neutrino mass generation.


title:
Establishing a relation between mass and spin of stellar mass black
  holes

abstract:
  Stellar mass black holes (SMBHs), forming by the core collapse of very
massive, rapidly rotating stars, are expected to exhibit a high density
accretion disk around them developed from the spinning mantle of the collapsing
star. A wide class of such disks, due to their high density and temperature,
are effective emitters of neutrinos and hence called neutrino cooled disks.
Tracking the physics relating the observed (neutrino) luminosity to the mass,
spin of black holes (BHs) and the accretion rate (M_dot) of such disks, here we
establish a correlation between the spin and mass of SMBHs at their formation
stage. Our work shows that spinning BHs are more massive than non-spinning BHs
for a given M_dot. However, slowly spinning BHs can turn out to be more massive
than spinning BHs if M_dot at their formation stage was higher compared to
faster spinning BHs.


title:
Shuffling: Improving Data Security in Ad Hoc Networks based on Unipath
  Routing

abstract:
  An ad hoc network is a self-organizing network with help of Access Point (AP)
of wireless links connecting nodes to another. The nodes can communicate
without infrastructure network. They form an random topology (BSS/ESS), where
the nodes play the role of routers and are free to move arbitrarily. Ad hoc
networks confirmed their efficiency being used in different fields but they are
highly vulnerable to security attacks and dealing with this is one of the main
challenges of these networks today. In recent times, a few solutions are
proposed to provide authentication, confidentiality, availability, secure
routing and intrusion prevention in ad hoc networks. Employ security in such
dynamically changing networks is a hard task. Ad hoc network uniqueness must be
taken into contemplation to be clever to design efficient clarification. Here
we spotlight on improving the flow transmission confidentiality in ad hoc
networks based on unipath routing. Definitely, we take advantage of the being
of multiple paths between nodes in an ad hoc network to increase the
confidentiality robustness of transmitted data with the help of Access Point.
In our approach the original message to secure is split into shares through
access point that are encrypted and combined then transmitted along different
disjointed existing paths between sender and receiver. Still if an attacker
succeeds to attain one or more transmitted contribute to the probability that
the unique message will be reconstituted is very low.


title:
A Conceptual Framework for Definition of the Correlation Between Company
  Size Categories and the Proliferation of Business Information Systems in
  Hungary

abstract:
  Based on a conceptual model, this paper aims to explore the background of the
decision-making process leading to the introduction of business information
systems among enterprises in Hungary. Together with presenting the problems
arising in the course of the implementation of such systems, their usage
patterns are also investigated. A strong correlation is established between the
size of an enterprise, the scope of its business activities and the range of
the business information systems it applies.


title:
The Calibration of Star Formation Rate Indicators for WISE 22 Micron
  Selected Galaxies in the SDSS

abstract:
  We study star formation rate (SFR) indicators for Wide-field Infrared Survey
Explorer (WISE) 22 \mu m selected, star-forming galaxies at 0.01 < z < 0.3 in
the Sloan Digital Sky Survey. Using extinction-corrected H\alpha\ luminosities
and total infrared luminosities as reference SFR estimates, we calibrate WISE
mid-infrared (MIR) related SFR indicators. Both 12 and 22 \mu m monochromatic
luminosities correlate well with the reference SFR estimates, but tend to
underestimate SFRs of metal-poor galaxies (at lower than solar metallicity),
consistent with previous studies. We mitigate this metallicity dependence using
a linear combination of observed H\alpha\ and WISE MIR luminosities for SFR
estimates. The combination provides robust SFR measurements as Kennicutt et al.
(2009) applied to Spitzer data. However, we find that the coefficient a in
L_H\alpha(obs) + a L_MIR increases with SFR, and show that a non-linear
combination of observed H\alpha\ and MIR luminosities gives the best SFR
estimates with small scatters and with little dependence on physical
parameters. Such a combination of H\alpha\ and MIR luminosities for SFR
estimates is first applied to WISE data. We provide several SFR recipes using
WISE data applicable to galaxies with 0.1 <~ SFR (M_sun yr^-1) <~ 100.


title:
Colour gradients of high-redshift Early-Type Galaxies from
  hydrodynamical monolithic models

abstract:
  We analyze the evolution of colour gradients predicted by the hydrodynamical
models of early type galaxies (ETGs) in Pipino et al. (2008), which reproduce
fairly well the chemical abundance pattern and the metallicity gradients of
local ETGs. We convert the star formation (SF) and metal content into colours
by means of stellar population synthetic model and investigate the role of
different physical ingredients, as the initial gas distribution and content,
and eps_SF, i.e. the normalization of SF rate. From the comparison with high
redshift data, a full agreement with optical rest-frame observations at z < 1
is found, for models with low eps_SF, whereas some discrepancies emerge at 1 <
z < 2, despite our models reproduce quite well the data scatter at these
redshifts. To reconcile the prediction of these high eps_SF systems with the
shallower colour gradients observed at lower z we suggest intervention of 1-2
dry mergers. We suggest that future studies should explore the impact of wet
galaxy mergings, interactions with environment, dust content and a variation of
the Initial Mass Function from the galactic centers to the peripheries.


title:
The Roche limit for close-orbiting planets: Minimum density, composition
  constraints, and application to the 4.2-hour planet KOI 1843.03

abstract:
  The requirement that a planet must orbit outside of its Roche limit gives a
lower limit on the planet's mean density. The minimum density depends almost
entirely on the orbital period and is immune to systematic errors in the
stellar properties. We consider the implications of this density constraint for
the newly-identified class of small planets with periods shorter than half a
day. When the planet's radius is known accurately, this lower limit to the
density can be used to restrict the possible combinations of iron and rock
within the planet. Applied to KOI 1843.03, with a radius of 0.6 Earth radii and
the shortest known orbital period of 4.245 hr, the planet's mean density must
be greater than approximately 7 g/cm^3. By modeling the planetary interior
subject to this constraint, we find the composition of the planet must be
mostly iron, with at most a modest fraction of silicates (less than
approximately 30% by mass).


title:
Is there a metallicity ceiling to form carbon stars? - A novel technique
  reveals a scarcity of C stars in the inner M31 disk

abstract:
  We use medium-band near-infrared (NIR) Hubble Space Telescope WFC3 photometry
with model NIR spectra of Asymptotic Giant Branch (AGB) stars to develop a new
tool for efficiently distinguishing carbon-rich (C-type) AGB stars from
oxygen-rich (M-type) AGB stars in galaxies at the edge of and outside the Local
Group. We present the results of a test of this method on a region of the inner
disk of M31, where we find a surprising lack of C stars, contrary to the
findings of previous C star searches in other regions of M31. We find only 1
candidate C star (plus up to 6 additional, less certain C stars candidates),
resulting in an extremely low ratio of C to M stars (C/M =
(3.3(+20,-0.1))x10^-4) that is 1-2 orders of magnitude lower than other C/M
estimates in M31. The low C/M ratio is likely due to the high metallicity in
this region which impedes stars from achieving C/O > 1 in their atmospheres.
These observations provide stringent constraints evolutionary models of
metal-rich AGB stars and suggest that there is a metallicity threshold above
which M stars are unable to make the transition to C stars, dramatically
affecting AGB mass loss and dust production and, consequently, the observed
global properties of metal-rich galaxies.


title: Wino Dark Matter Under Siege

abstract:
  A fermion triplet of SU(2)_L - a wino - is a well-motivated dark matter
candidate. This work shows that present-day wino annihilations are constrained
by indirect detection experiments, with the strongest limits coming from
H.E.S.S. and Fermi. The bounds on wino dark matter are presented as a function
of mass for two scenarios: thermal (winos constitute a subdominant component of
the dark matter for masses less than 3.1 TeV) and non-thermal (winos comprise
all the dark matter). Assuming the NFW halo model, the H.E.S.S. search for
gamma-ray lines excludes the 3.1 TeV thermal wino; the combined H.E.S.S. and
Fermi results completely exclude the non-thermal scenario. Uncertainties in the
exclusions are explored. Indirect detection may provide the only probe for
models of anomaly plus gravity mediation where the wino is the lightest
superpartner and scalars reside at the 100 TeV scale.


title: Analytic results for two-loop master integrals for Bhabha scattering I

abstract:
  We evaluate analytically the master integrals for one of two types of planar
families contributing to massive two-loop Bhabha scattering in QED. As in our
previous paper, we apply a recently suggested new strategy to solve
differential equations for master integrals for families of Feynman integrals.
The crucial point of this strategy is to use a new basis of the master
integrals where all master integrals are pure functions of uniform weight. This
allows to cast the differential equations into a simple canonical form, which
can straightforwardly be integrated order by order in epsilon in dimensional
regularization. The boundary conditions are also particularly transparent in
this setup. We identify the class of functions relevant to this problem to all
orders in epsilon. We present the results up to weight four for all except one
integrals in terms of a subset of Goncharov polylogarithms, which one may call
two-dimensional harmonic polylogarithms. For one integral, and more generally
at higher weight, the solution is written in terms of Chen iterated integrals.


title:
Super-massive planets around late-type stars - the case of
  OGLE-2012-BLG-0406Lb

abstract:
  The core accretion theory of planetary formation does not predict that
super-Jupiters will form beyond the snow line of a low mass stars. We present a
discovery of 3.9 +- 1.2 M_Jup mass planet orbiting the 0.59 +- 0.17 M_Sun star
using the gravitational microlensing method. During the event, the projected
separation of the planet and the star is 3.9 +- 1.0 AU i.e., the planet is
significantly further from the host star than the snow line. This is a fourth
such planet discovered using the microlensing technique and challenges the core
accretion theory.


title: NGC 362: another globular cluster with a split red giant branch

abstract:
  We obtained FLAMES GIRAFFE+UVES spectra for both first and second-generation
red giant branch (RGB) stars in the globular cluster (GC) NGC 362 and used them
to derive abundances of 21 atomic species for a sample of 92 stars. The
surveyed elements include proton-capture (O, Na, Mg, Al, Si), alpha-capture
(Ca, Ti), Fe-peak (Sc, V, Mn, Co, Ni, Cu), and neutron-capture elements (Y, Zr,
Ba, La, Ce, Nd, Eu, Dy). The analysis is fully consistent with that presented
for twenty GCs in previous papers of this series. Stars in NGC 362 seem to be
clustered into two discrete groups along the Na-O anti-correlation, with a gap
at [O/Na] 0 dex. Na-rich, second generation stars show a trend to be more
centrally concentrated, although the level of confidence is not very high. When
compared to the classical second-parameter twin NGC 288, with similar
metallicity, but different horizontal branch type and much lower total mass,
the proton-capture processing in stars of NGC 362 seems to be more extreme,
confirming previous analysis. We discovered the presence of a secondary RGB
sequence, redder than the bulk of the RGB: a preliminary estimate shows that
this sequence comprises about 6% of RGB stars. Our spectroscopic data and
literature photometry indicate that this sequence is populated almost
exclusively by giants rich in Ba, and probably rich in all s-process elements,
as found in other clusters. In this regards, NGC 362 joins previously studied
GCs like NGC 1851, NGC 6656 (M 22), and NGC 7089 (M 2).


title: Gravitational wave emission from binary supermassive black holes

abstract:
  Massive black hole binaries (MBHBs) are unavoidable outcomes of the
hierarchical structure formation process, and according to the theory of
general relativity are expected to be the loudest gravitational wave (GW)
sources in the Universe. In this article I provide a broad overview of MBHBs as
GW sources. After reviewing the basics of GW emission from binary systems and
of MBHB formation, evolution and dynamics, I describe in some details the
connection between binary properties and the emitted gravitational waveform.
Direct GW observations will provide an unprecedented wealth of information
about the physical nature and the astrophysical properties of these extreme
objects, allowing to reconstruct their cosmic history, dynamics and coupling
with their dense stellar and gas environment. In this context I describe
ongoing and future efforts to make a direct detection with space based
interferometry and pulsar timing arrays, highlighting the invaluable scientific
payouts of such enterprises.


title: Perturbations of W(infinity) CFTs

abstract:
  The holographic duals of higher spin theories on AdS_3 are described by the
large N limit of a family of minimal model CFTs, whose symmetry algebra is
equivalent to W(infinity)[lambda]. We study perturbations of these limit
theories, and show that they possess a marginal symmetry-preserving
perturbation that describes switching on the 1/N corrections. We also test our
general results for the specific cases of lambda=0,1, where free field
realisations are available.


title:
Burying a Binary: Dynamical Mass Loss and a Continuous Optically-Thick
  Outflow Explain the Candidate Stellar Merger V1309 Scorpii

abstract:
  V1309 Sco was proposed to be a stellar merger and a common envelope transient
based on the pre-outburst light curve of a contact eclipsing binary with a
rapidly decaying orbital period. Using published data, I show that the period
decay timescale P/Pdot of V1309 Sco decreased from ~1000 to ~170 years in less
than about 6 years, which implies a very high value of second period
derivative. I argue that V1309 Sco experienced an onset of dynamical mass loss
through the outer Lagrange point, which eventually obscured the binary. The
photosphere of the resulting continuous optically-thick outflow expands as the
mass-loss rate increases, explaining the ~200 day rise to optical maximum. The
model yields the mass-loss rate of the binary star as a function of time and
fits the observed light curve remarkably well. It is also possible to
observationally constrain the properties of the surface layers undergoing the
dynamical mass loss. V1309 Sco is thus a prototype of a new class of stellar
transients distinguished by a slow rise to optical maximum that are driven by
dynamical mass loss from a binary. I discuss implications of these findings for
stellar transients and other suggested common envelope events.


title: Keck-I MOSFIRE spectroscopy of the z~12 candidate galaxy UDFj-39546284

abstract:
  We report the results of deep (4.6h) H band spectroscopy of the well studied
z~12 H-band dropout galaxy candidate UDFj-39546284 with MOSFIRE on Keck-I.
These data reach a sensitivity of 5-10 x 10^-19 erg s^-1 cm^-2 per 4.4 Angstrom
resolution element between sky lines. Previous papers have argued this source
could either be a large equivalent width line emitting galaxy at 2<z<3.5 or a
luminous galaxy at z~12. We find a 2.2 sigma peak associated with a line
candidate in deep Hubble-Space-Telescope Wide-Field-Camera 3 Infrared grism
observations, but at a lower flux than what was expected. After considering
several possibilities we conclude these data can not conclusively confirm or
reject the previous line detection, and significantly deeper spectroscopic
observations are required. We also search for low-redshift emission lines in
ten other 7<z<10 z, Y, and J-dropout candidates in our mask and find no
significant detections.


title: CMB Power Asymmetry from Primordial Sound Speed Parameter

abstract:
  The hemispherical power asymmetry in the cosmic microwave background may be
explained by the modulation of some primordial cosmological parameter, such as
the sound speed of the inflaton. This modulation can be achieved by the
perturbation of a light field during inflation. We numerically examine this
mechanism and show it can be consistent with current observations. Further,
this model predicts that the power asymmetry also exists in the
temperature-polarization correlation and polarization autocorrelation with the
same shape, and in primordial non-gaussianity of equilateral type with a
particular shape. Therefore, our mechanism is observationally detectable in
forthcoming experiments.


title:
Self-Injection Locking and Phase-Locked States in Microresonator-Based
  Optical Frequency Combs

abstract:
  Microresonator-based optical frequency combs have been a topic of extensive
research during the last few years. Several theoretical models for the comb
generation have been proposed; however, they do not comprehensively address
experimental results that show a variety of independent comb generation
mechanisms. Here, we present frequency-domain experiments that illuminate the
transition of microcombs into phase-locked states, which show characteristics
of injection locking between ensembles of comb modes. In addition, we
demonstrate the existence of equidistant optical frequency combs that are phase
stable but with non-deterministic phase relationships between individual comb
modes.


title:
Localization and topology protected quantum coherence at the edge of
  'hot' matter

abstract:
  Topological phases are often characterized by special edge states confined
near the boundaries by an energy gap in the bulk. On raising temperature, these
edge states are lost in a clean system due to mobile thermal excitations.
Recently however, it has been established that disorder can localize an
isolated many body system, potentially allowing for a sharply defined
topological phase even in a highly excited state. Here we show this to be the
case for the topological phase of a one dimensional magnet with quenched
disorder, which features spin one-half excitations at the edges. The time
evolution of a simple, highly excited, initial state is used to reveal quantum
coherent edge spins. In particular, we demonstrate, using theoretical arguments
and numerical simulation, the coherent revival of an edge spin over a time
scale that grows exponentially bigger with system size. This is in sharp
contrast to the general expectation that quantum bits strongly coupled to a
'hot' many body system will rapidly lose coherence.

categories: cond-mat.dis-nn cond-mat.quant-gas cond-mat.str-el quant-ph


title:
The Subaru Coronagraphic Extreme Adaptive Optics Imager: First Results
  and On-Sky Performance

abstract:
  We present new on-sky results for the Subaru Coronagraphic Extreme Adaptive
Optics imager (SCExAO) verifying and quantifying the contrast gain enabled by
key components: the closed-loop coronagraphic low-order wavefront sensor
(CLOWFS) and focal plane wavefront control ("speckle nulling"). SCExAO will
soon be coupled with a high-order, Pyramid wavefront sensor which will yield >
90% Strehl ratio and enable 10^6--10^7 contrast at small angular separations
allowing us to image gas giant planets at solar system scales. Upcoming
instruments like VAMPIRES, FIRST, and CHARIS will expand SCExAO's science
capabilities.


title: Photometry Study of Open Cluster NGC 7788

abstract:
  A new CCD photometry survey of the open cluster NGC7788 in U, B, V, R and I
colors to magnitude V=20 is present. Extensive comparison of our photometry
with other published dataset shows excellent agreement, indicating that CCD
photometry is capable of producing a uniform set of measurements consistent
with the photometric system defined primarily by the Landolt standard sequence.
For this study we used the 113 stars considered to be cluster members by Becker
on 1965.


title: Exothermic Double-Disk Dark Matter

abstract:
  If a subdominant component of dark matter (DM) interacts via long-range dark
force carriers it may cool and collapse to form complex structures within the
Milky Way galaxy, such as a rotating dark disk. This scenario was proposed
recently and termed "Double-Disk Dark Matter" (DDDM). In this paper we consider
the possibility that DDDM remains in a cosmologically long-lived excited state
and can scatter exothermically on nuclei (ExoDDDM). We investigate the current
status of ExoDDDM direct detection and find that ExoDDDM can readily explain
the recently announced ~3 sigma excess observed at CDMS-Si, with almost all of
the 90% best-fit parameter space in complete consistency with limits from other
experiments, including XENON10 and XENON100. In the absence of
isospin-dependent couplings, this consistency requires light DM with mass
typically in the 5-15 GeV range. The hypothesis of ExoDDDM can be tested in
direct detection experiments through its peaked recoil spectra, reduced annual
modulation amplitude, and, in some cases, its novel time-dependence. We also
discuss future direct detection prospects and additional indirect constraints
from colliders and solar capture of ExoDDDM. As theoretical proof-of-principle,
we combine the features of exothermic DM models and DDDM models to construct a
complete model of ExoDDDM, exhibiting all the required properties.


title:
Unusual reflection of electromagnetic radiation from a stack of graphene
  layers at oblique incidence

abstract:
  We study the interaction of electromagnetic (EM) radiation with single-layer
graphene and a stack of parallel graphene sheets at arbitrary angles of
incidence. It is found that the behavior is qualitatively different for
transverse magnetic (or p-polarized) and transverse electric (or s-polarized)
waves. In particular, the absorbance of single-layer graphene attains minimum
(maximum) for p (s) polarization, at the angle of total internal reflection
when the light comes from a medium with a higher dielectric constant. In the
case of equal dielectric constants of the media above and beneath graphene, for
grazing incidence graphene is almost 100% transparent to p-polarized waves and
acts as a tunable mirror for the s-polarization. These effects are enhanced for
the stack of graphene sheets, so the system can work as a broad band polarizer.
It is shown further that a periodic stack of graphene layers has the properties
of an one-dimensional photonic crystal, with gaps (or stop--bands) at certain
frequencies. When an incident EM wave is reflected from this photonic crystal,
the tunability of the graphene conductivity renders the possibility of
controlling the gaps, and the structure can operate as a tunable
spectral--selective mirror.


title:
Some notes on applying computational divided differencing in
  optimization

abstract:
  We consider the problem of accurate computation of the finite difference
$f(\x+\s)-f(\x)$ when $\Vert\s\Vert$ is very small. Direct evaluation of this
difference in floating point arithmetic succumbs to cancellation error and
yields 0 when $\s$ is sufficiently small. Nonetheless, accurate computation of
this finite difference is required by many optimization algorithms for a
"sufficient decrease" test. Reps and Rall proposed a programmatic
transformation called "computational divided differencing" reminiscent of
automatic differentiation to compute these differences with high accuracy. The
running time to compute the difference is a small constant multiple of the
running time to compute $f$. Unlike automatic differentiation, however, the
technique is not fully general because of a difficulty with branching code
(i.e., `if' statements). We make several remarks about the application of
computational divided differencing to optimization. One point is that the
technique can be used effectively as a stagnation test.


title: LHC jet suppression of light and heavy flavor observables

abstract:
  Jet suppression of light and heavy flavor observables is considered to be an
excellent tool to study the properties of QCD matter created in
ultra-relativistic heavy ion collisions. We calculate the suppression patterns
of light hadrons, D mesons, non-photonic single electrons and non-prompt
$J/\psi$ in Pb+Pb collisions at LHC. We use a theoretical formalism that takes
into account finite size {\it dynamical} QCD medium with finite magnetic mass
effects and running coupling, which is integrated into a numerical procedure
that uses no free parameters in model testing. We obtain a good agreement with
the experimental results across different experiments/particle species. Our
results show that the developed theoretical formalism can robustly explain
suppression data in ultra relativistic heavy ion collisions, which strongly
suggests that pQCD in Quark-Gluon Plasma is able to provide a reasonable
description of the underlying jet physics at LHC.


title: Hydrogen and helium in the spectra of Type Ia supernovae

abstract:
  We present predictions for hydrogen and helium emission line luminosities
from circumstellar matter around Type Ia supernovae (SNe Ia) using time
dependent photoionization modeling. ESO/VLT optical echelle spectra of the SN
Ia 2000cx were taken before and up to 70 days after maximum. We detect no
hydrogen and helium lines, and place an upper limit on the mass loss rate for
the putative wind of less than 1.3EE{-5} solar masses per year, assuming a
speed of 10 km/s and solar abundances for the wind. In a helium-enriched case,
the best line to constrain the mass loss would be He I 10,830 A. We confirm the
details of interstellar Na I and Ca II absorption towards SN 2000cx as
discussed by Patat et al., but also find evidence for 6613.56 A Diffuse
Interstellar Band (DIB) absorption in the Milky Way. We discuss measurements of
the X-ray emission from the interaction between the supernova ejecta and the
wind and we re-evaluate observations of SN 1992A obtained 16 days after maximum
by Schlegel & Petre. We find an upper limit of 1.3EE{-5} solar masses per year.
These results, together with the previous observational work on the normal SNe
Ia 1994D and 2001el, disfavour a symbiotic star in the upper mass loss rate
regime from being the likely progenitor scenario for these SNe. To constrain
hydrogen in late time spectra, we present ESO/VLT and ESO/NTT optical and
infrared observations of SNe Ia 1998bu and 2000cx 251-388 days after maximum.
We see no hydrogen line emission in SNe 1998bu and 2000cx at these epochs, and
we argue from modeling that the mass of such hydrogen-rich gas must be less
than 0.03 solar masses for both supernovae. Comparing similar upper limits with
recent models of Pan et al., it seems hydrogen-rich donors with a separation of
less than 5 times the radius of the donor may be ruled out for the five SNe Ia
1998bu, 2000cx, 2001el, 2005am and 2005cf.


title: The core shift effect in the blazar 3C 454.3

abstract:
  Opacity-driven shifts of the apparent VLBI core position with frequency (the
"core shift" effect) probe physical conditions in the innermost parts of jets
in active galactic nuclei. We present the first detailed investigation of this
effect in the brightest gamma-ray blazar 3C454.3 using direct measurements from
simultaneous 4.6-43 GHz VLBA observations, and a time lag analysis of 4.8-37
GHz lightcurves from the UMRAO, CrAO, and Metsahovi observations in 2007-2009.
The results support the standard Konigl model of jet physics in the VLBI core
region. The distance of the core from the jet origin r_c(nu), the core size
W(nu), and the lightcurve time lag DT(nu) all depend on the observing frequency
nu as r_c(nu)~W(nu)~ DT(nu)~nu^-1/k. The obtained range of k=0.6-0.8 is
consistent with the synchrotron self-absorption being the dominating opacity
mechanism in the jet. The similar frequency dependence of r_c(nu) and W(nu)
suggests that the external pressure gradient does not dictate the jet geometry
in the cm-band core region. Assuming equipartition, the magnetic field strength
scales with distance r as B = 0.4(r/1pc)^-0.8 G. The total kinetic power of
electron/positron jet is about 10^44 ergs/s.


title:
Decision Making for Inconsistent Expert Judgments Using Negative
  Probabilities

abstract:
  In this paper we provide a simple random-variable example of inconsistent
information, and analyze it using three different approaches: Bayesian,
quantum-like, and negative probabilities. We then show that, at least for this
particular example, both the Bayesian and the quantum-like approaches have less
normative power than the negative probabilities one.


title:
Network Formation Games with Heterogeneous Players and the Internet
  Structure

abstract:
  We study the structure and evolution of the Internet's Autonomous System (AS)
interconnection topology as a game with heterogeneous players. In this network
formation game, the utility of a player depends on the network structure, e.g.,
the distances between nodes and the cost of links. We analyze static properties
of the game, such as the prices of anarchy and stability and provide explicit
results concerning the generated topologies. Furthermore, we discuss dynamic
aspects, demonstrating linear convergence rate and showing that only a
restricted subset of equilibria is feasible under realistic dynamics. We also
consider the case where utility (or monetary) transfers are allowed between the
players.


title:
Migration-selection balance at multiple loci and selection on dominance
  and recombination

abstract:
  A steady influx of a single deleterious multilocus genotype will impose
genetic load on the resident population and leave multiple descendants carrying
various numbers of the foreign alleles. Provided that the foreign types are
rare at equilibrium, and that all immigrant genes will eventually be eliminated
by selection, the population structure can be inferred explicitly from the
deterministic branching process taking place within a single immigrant lineage.
Unless the migration and recombination rates were high, this simple method was
a very close approximation to the simulated migration-selection balance with
all possible multilocus genotypes considered.


title:
Conformal Field Theory at the Lattice Level: Discrete Complex Analysis
  and Virasoro Structure

abstract:
  Critical statistical mechanics and Conformal Field Theory (CFT) are
conjecturally connected since the seminal work of Beliavin, Polyakov, and
Zamolodchikov [BPZ84a]. Both exhibit exactly solvable structures in two
dimensions. A long-standing question [ItTh87] concerns whether there is a
direct link between these structures, that is, whether the Virasoro algebra
representations of CFT, the distinctive feature of CFT in two dimensions, can
be found within lattice models of statistical mechanics. We give a positive
answer to this question for the discrete Gaussian free field and for the Ising
model, by connecting the structures of discrete complex analysis in the lattice
models with the Virasoro symmetry that is expected to describe their scaling
limits. This allows for a tight connection of a number of objects from the
lattice model world and the field theory one. In particular, our results link
the CFT local fields with lattice local fields introduced in [GHP19] and the
probabilistic formulation of the lattice model with the continuum correlation
functions. Our construction is a decisive step towards establishing the
conjectured correspondence between the correlation functions of the CFT fields
and those of the lattice local fields. In particular, together with the
upcoming [CHI19], our construction will complete the picture initiated in
[HoSm13, Hon12, CHI15], where a number of conjectures relating specific Ising
lattice fields and CFT correlations were proven.


title: ATLASGAL --- properties of compact HII regions and their natal clumps

abstract:
  We present a complete sample of molecular clumps containing compact and
ultra-compact (UC) HII regions between \ell=10\degr and 60\degr\ and
$|b|<1\degr, identified by combining the the ATLASGAL submm and CORNISH radio
continuum surveys with visual examination of archival infrared data. Our sample
is complete to optically thin, compact and UCHII regions driven by a zero age
main sequence star of spectral type B0 or earlier embedded within a 1,000 Msun
clump. In total we identify 213 compact and UCHII regions, associated with 170
clumps. Unambiguous kinematic distances are derived for these clumps and used
to estimate their masses and physical sizes, as well as the Lyman continuum
fluxes and sizes of their embedded HII regions. We find a clear lower envelope
for the surface density of molecular clumps hosting massive star formation of
0.05 g cm^{-2}, which is consistent with a similar sample of clumps associated
with 6.7 GHz masers. The mass of the most massive embedded stars is closely
correlated with the mass of their natal clump. Young B stars appear to be
significantly more luminous in the ultraviolet than predicted by current
stellar atmosphere models. The properties of clumps associated with compact and
UCHII regions are very similar to those associated with 6.7 GHz methanol masers
and we speculate that there is little evolution in the structure of the
molecular clumps between these two phases. Finally, we identify a significant
peak in the surface density of compact and UCHII regions associated with the
W49A star-forming complex, noting that this complex is truly one of the most
massive and intense regions of star formation in the Galaxy.


title:
Front speed enhancement by incompressible flows in three or higher
  dimensions

abstract:
  We study, in dimensions $N\geq 3$, the family of first integrals of an
incompressible flow: these are $H^{1}_{loc}$ functions whose level surfaces are
tangent to the streamlines of the advective incompressible field. One main
motivation for this study comes from earlier results proving that the existence
of nontrivial first integrals of an incompressible flow $q$ is the main key
that leads to a "linear speed up" by a large advection of pulsating traveling
fronts solving a reaction-advection-diffusion equation in a periodic
heterogeneous framework. The family of first integrals is not well understood
in dimensions $N\geq3$ due to the randomness of the trajectories of $q$ and
this is in contrast with the case N=2. By looking at the domain of propagation
as a union of different components produced by the advective field, we provide
more information about first integrals and we give a class of incompressible
flows which exhibit `ergodic components' of positive Lebesgue measure (hence
are not shear flows) and which, under certain sharp geometric conditions, speed
up the KPP fronts linearly with respect to the large amplitude. In the proofs,
we establish a link between incompressibility, ergodicity, first integrals, and
the dimension to give a sharp condition about the asymptotic behavior of the
minimal KPP speed in terms the configuration of ergodic components.


title:
Alternating Product Ciphers: A Case for Provable Security Comparisons
  (extended abstract)

abstract:
  We formally study iterated block ciphers that alternate between two sequences
of independent and identically distributed (i.i.d.) rounds. It is demonstrated
that, in some cases the effect of alternating increases security, while in
other cases the effect may strictly decrease security relative to the
corresponding product of one of its component sequences. As this would appear
to contradict conventional wisdom based on the ideal cipher approximation, we
introduce new machinery for provable security comparisons. The comparisons made
here simultaneously establish a coherent ordering of security metrics ranging
from key-recovery cost to computational indistinguishability.


title:
The shocks during the accretion of an ultrarelativistic supersonic gas
  onto a rotating black hole

abstract:
  In this work, we track the evolution of an ultrarelativistic fluid onto a
Kerr black hole, on the equatorial plane. In this treatment, we consider the
limit where the rest mass density is neglected, that is, the approximation is
valid in the regime where the internal energy dominates over the rest mass
density. We particularly concentrate in the case of a gas with $\Gamma$ = 4/3,
which corresponds to a radiation fluid. We show, as in several cases, that a
shock cone appears when the asymptotic velocity of the fluid is larger than the
asymptotic relativistic sound speed of the gas. On the other hand, in order to
show the system approaches to steady state, we calculate the accreted total
energy rate on a spherical surface. Finally, we also show the gas distribution
and various of its properties.


title:
Theory of the Electron Spin Resonance in the Heavy Fermion Metal
  \beta-YbAlB4

abstract:
  The heavy fermion metal \beta-YbAlB4 exhibits a bulk room temperature
conduction electron ESR signal which evolves into an Ising-anisotropic
f-electron signal exhibiting hyperfine features at low temperatures. We develop
a theory for this phenomenon based on the development of resonant scattering
off a periodic array of Kondo centers. We show that the hyperfine structure
arises from the scattering off the Yb atoms with non zero nuclear spin, while
the constancy of the ESR intensity is a consequence of the presence of CEF
excitations of the order of the hybridization strength.


title:
Well-posedness and ill-posedness results for the Novikov-Veselov
  equation

abstract:
  In this paper we study the Novikov-Veselov equation and the related modified
Novikov-Veselov equation in certain Sobolev spaces. We prove local
well-posedness in H^s (R2) for s > 1/2 for the Novikov-Veselov equation, and
local well-posedness in H^s (R2) for s > 1 for the modified Novikov-Veselov
equation. Finally we point out some ill-posedness issues for the Novikov-
Veselov equation in the supercritical regime.


title: Common fixed points for $\psi-(\alpha,\beta, m)$-contraction pairs

abstract:
  In this paper we establish some common fixed point theorem for a new class of
pair of contractions mappings, called $\psi-(\alpha,\beta, m)$-contraction
pairs, which we will assume occasionally weakly compatible and satisfying the
property (E.A.).


title: Diffuse interstellar bands in M33

abstract:
  We present the first sample of diffuse interstellar bands (DIBs) in the
nearby galaxy M33. Studying DIBs in other galaxies allows the behaviour of the
carriers to be examined under interstellar conditions which can be quite
different from those of the Milky Way, and to determine which DIB properties
can be used as reliable probes of extragalactic interstellar media.
Multi-object spectroscopy of 43 stars in M33 has been performed using
Keck/DEIMOS. The stellar spectral types were determined and combined with
literature photometry to determine the M33 reddenings E(B-V)_M33. Equivalent
widths or upper limits have been measured for the {\lambda}5780 DIB towards
each star. DIBs were detected towards 20 stars, demonstrating that their
carriers are abundant in M33. The relationship with reddening is found to be at
the upper end of the range observed in the Milky Way. The line of sight towards
one star has an unusually strong ratio of DIB equivalent width to E(B-V)_M33,
and a total of seven DIBs were detected towards this star.


title:
On a common generalization of Shelah's 2-rank, dp-rank, and o-minimal
  dimension

abstract:
  In this paper, we build a dimension theory related to Shelah's 2-rank,
dp-rank, and o-minimal dimension. We call this dimension op-dimension. We
exhibit the notion of the n-multi-order property, generalizing the order
property, and use this to create op-rank, which generalizes 2-rank. From this
we build op-dimension. We show that op-dimension bounds dp-rank, that
op-dimension is sub-additive, and op-dimension generalizes o-minimal dimension
in o-minimal theories.


title: Vertex Operator Superalgebras and Odd Trace Functions

abstract:
  We begin by reviewing Zhu's theorem on modular invariance of trace functions
associated to a vertex operator algebra, as well as a generalisation by the
author to vertex operator superalgebras. This generalisation involves objects
that we call `odd trace functions'. We examine the case of the N=1
superconformal algebra. In particular we compute an odd trace function in two
different ways, and thereby obtain a new representation theoretic
interpretation of a well known classical identity due to Jacobi concerning the
Dedekind eta function.


title:
A mean-field Babcock-Leighton solar dynamo model with long-term
  variability

abstract:
  Dynamo models relying on the Babcock-Leighton mechanism are successful in
reproducing most of the solar magnetic field dynamical characteristics.
However, considering that such models operate only above a lower magnetic field
threshold, they do not provide an appropriate magnetic field regeneration
process characterizing a self-sustainable dynamo. In this work we consider the
existence of an additional \alpha-effect to the Babcock-Leighton scenario in a
mean-field axisymmetric kinematic numerical model. Both poloidal field
regeneration mechanisms are treated with two different strength-limiting
factors. Apart from the solar anti-symmetric parity behavior, the main solar
features are reproduced: cyclic polarity reversals, mid-latitudinal equatorward
migration of strong toroidal field, poleward migration of polar surface radial
fields, and the quadrature phase shift between both. Long-term variability of
the solutions exhibits lengthy periods of minimum activity followed by
posterior recovery, akin to the observed Maunder Minimum. Based on the analysis
of the residual activity during periods of minimum activity, we suggest that
these are caused by a predominance of the \alpha-effect over the
Babcock-Leighton mechanism in regenerating the poloidal field.


title:
Detecting a Stochastic Gravitational Wave Background in the presence of
  a Galactic Foreground and Instrument Noise

abstract:
  Detecting a stochastic gravitational wave background requires that we first
understand and model any astrophysical foregrounds. In the millihertz frequency
band, the predominate foreground signal will be from unresolved white dwarf
binaries in the galaxy. We build on our previous work to show that a stochastic
gravitational wave background can be detected in the presence of both
instrument noise and a galactic confusion foreground. The key to our approach
is accurately modeling the spectra for each of the various signal components.
We simulate data for a gigameter Laser Interferometer Space Antenna (LISA)
operating in the mHz frequency band detector operating with both 6- and
4-links. We obtain posterior distribution functions for the instrument noise
parameters, the galaxy level and modulation parameters, and the stochastic
background energy density. We find that we are able to detect a scale-invariant
stochastic background with energy density as low as Omega_gw = 2e-13 for a
6-link interferometer and Omega_gw = 5e-13 for a 4-link interferometer with one
year of data.


title:
An Astrometric Search for a Sub-stellar Companion of the M8.5 Dwarf TVLM
  513-46546 Using Very Long Baseline Interferometry

abstract:
  We conducted multi-epoch VLBI observations to search for astrometric reflex
motion caused by a sub-stellar companion of the M8.5 dwarf TVLM 513-46546. The
observations yield an absolute parallax corresponding to a distance of
10.762+/-0.027 pc and a proper motion of 78.09+/-0.17 mas/yr. From the absence
of significant residual motion, we place an upper limit to any reflex motion
caused by a companion, extending the parameter space covered by previous
near-infrared direct-imaging searches. By covering different orbital periods,
the data exclude a phase-space of companion masses and orbital periods ranging
from 3.8 Mjup with an orbital radius of ~0.05 AU (orbital period of 16 days) to
0.3 Mjup with an orbital radius of ~0.7 AU (orbital period of 710 days).


title:
Genomic identification of founding haplotypes reveals the history of the
  selfing species Capsella rubella

abstract:
  The shift from outcrossing to self-fertilization is among the most common
transitions in plants. Until recently, however, a genome-wide view of this
transition has been obscured by a dearth of appropriate data and the lack of
appropriate population genomic methods to interpret such data. Here, we present
novel analyses detailing the origin of the selfing species, Capsella rubella,
which recently split from its outcrossing sister, Capsella grandiflora. Due to
the recency of the split, most variation within C. rubella is found within C.
grandiflora. We can therefore identify genomic regions where two C. rubella
individuals have inherited the same or different segments of ancestral
diversity (i.e. founding haplotypes) present in C. rubella's founder(s). Based
on this analysis, we show that C. rubella was founded by multiple individuals
drawn from a diverse ancestral population closely related to extant C.
grandiflora, that drift and selection have rapidly homogenized most of this
ancestral variation since C. rubella's founding, and that little novel
variation has accumulated within this time. Despite the extensive loss of
ancestral variation, the approximately 25% of the genome for which two C.
rubella individuals have inherited different founding haplotypes makes up
roughly 90% of the genetic variation between them. To extend these findings, we
develop a coalescent model that utilizes the inferred frequency of founding
haplotypes and variation within founding haplotypes to estimate that C. rubella
was founded by a potentially large number of individuals 50-100 kya, and has
subsequently experienced a 20X reduction in its effective population size. As
population genomic data from an increasing number of outcrossing/selfing pairs
are generated, analyses like this here will facilitate a fine-scaled view of
the evolutionary and demographic impact of the transition to
self-fertilization.


title: Cornering light Neutralino Dark Matter at the LHC

abstract:
  We investigate the current status of the light neutralino dark matter
scenario within the minimal supersymmetric standard model (MSSM) taking into
account latest results from the LHC. A discussion of the relevant constraints,
in particular from the dark matter relic abundance, leads us to a manageable
simplified model defined by a subset of MSSM parameters. Within this simplified
model we reinterpret a recent search for electroweak supersymmetric particle
production based on a signature including multi-taus plus missing transverse
momentum performed by the ATLAS collaboration. In this way we derive stringent
constraints on the light neutralino parameter space. In combination with
further experimental information from the LHC, such as dark matter searches in
the monojet channel and constraints on invisible Higgs decays, we obtain a
lower bound on the lightest neutralino mass of about 24 GeV. This limit is
stronger than any current limit set by underground direct dark matter searches
or indirect detection experiments. With a mild improvement of the sensitivity
of the multi-tau search, light neutralino dark matter can be fully tested up to
about 30 GeV.


title:
Consistency and Stability of a Milstein-Galerkin Finite Element Scheme
  for Semilinear SPDE

abstract:
  We present an abstract concept for the error analysis of numerical schemes
for semilinear stochastic partial differential equations (SPDEs) and
demonstrate its usefulness by proving the strong convergence of a
Milstein-Galerkin finite element scheme. By a suitable generalization of the
notion of bistability from Beyn & Kruse (DCDS B, 2010) to the semigroup
framework in Hilbert spaces, our main result includes a two-sided error
estimate of the spatio-temporal discretization. In an additional section we
derive an analogous result for a Milstein-Galerkin finite element scheme with
truncated noise.


title:
Finite cyclicity of quadratic slow-fast Darboux systems with a
  two-saddle loop

abstract:
  We prove that the cyclicity of a quadratic slow-fast integrable system of
Darboux type with a double heteroclinic loop is finite and uniformly bounded.


title:
(N+1)-dimensional Lorentzian evolving wormholes supported by polytropic
  matter

abstract:
  In this paper we study $(N+1)$-dimensional evolving wormholes supported by
energy satisfying a polytropic equation of state. The considered evolving
wormhole models are described by a constant redshift function and generalizes
the standard flat Friedmann-Robertson-Walker spacetime. The polytropic equation
of state allows us to consider in $(3+1)$-dimensions generalizations of the
phantom energy and the generalized Chaplygin gas sources.


title: Diophantine approximation of Mahler numbers

abstract:
  Suppose that $F(x)\in\mathbb{Z}[[x]]$ is a Mahler function and that $1/b$ is
in the radius of convergence of $F(x)$. In this paper, we consider the
approximation of $F(1/b)$ by algebraic numbers. In particular, we prove that
$F(1/b)$ cannot be a Liouville number. If $F(x)$ is also regular, we show that
$F(1/b)$ is either rational or transcendental, and in the latter case that
$F(1/b)$ is an $S$-number or a $T$-number.