title: sl(N)-Web categories

abstract:
  In this paper we use colored sl(N)-matrix factorizations, due to Wu and Y.Y.,
in order to categorify part of the quantum skew Howe duality defined by Cautis,
Kamnitzer and Morrison. In particular, we define web categories and
2-representations of Khovanov and Lauda's categorical quantum sl(m) on them. We
show that each such web category is equivalent to the category of finite
dimensional graded projective modules over a certain level N cyclotomic
Khovanov-Lauda-Rouquier algebra.


title:
Light-induced long-ranged disorder effect in ultra-dilute
  two-dimensional holes in GaAs heterojunction-insulated-gate
  field-effect-transistors

abstract:
  Comparing the results of transport measurements of strongly correlated
two-dimensional holes in a GaAs heterojunction-insulated-gate
field-effect-transistor obtained before and after a brief photo-illumination,
the light-induced disorder is found to cause qualitative changes suggesting
altered carrier states. For charge concentrations ranging from $3\times10^{10}$
$cm^{-2}$ down to $7\times10^{8}$ cm$^{-2}$, the post-illumination hole
mobility exhibits a severe suppression for charge densities below
$2\times10^{10}$ cm$^{-2}$, while almost no change for densities above. The
long-ranged nature of the disorder is identified. The temperature dependence of
the conductivity is also drastically modified by the disorder reconfiguration
from being nonactivated to activated.


title: Quantum subgroups of the compact quantum group SU_{-1}(3)

abstract:
  We study the (compact) quantum subgroups of the compact quantum group
$SU_{-1}(3)$: we show that any non-classical such quantum subgroup is a twist
of a compact subgroup of SU(3) or is isomorphic to a quantum subgroup of
$U_{-1}(2)$.


title: On the number of soft quanta in classical field configurations

abstract:
  A crucial ingredient in the large-N quantum portrait of black holes proposed
by Dvali and Gomez is the estimate of the number of soft quanta that make up
the classical gravitational field. It is argued here that the coherent state
formalism provides a way to calculate that number directly. As a consequence,
the average energy of the soft quanta is such that the typical geometric size
of the field source can be roughly interpreted as their de Broglie wavelength.
The calculation is done for the electromagnetic field and for Newtonian
gravity, and it is argued that the number of soft quanta should be unchanged in
General Relativity due to the long range nature of gravity.


title: The influence of a repulsive vector coupling in magnetized quark matter

abstract:
  We consider two flavor magnetized quark matter in the presence of a repulsive
vector coupling ($G_V$) devoting special attention to the low temperature
region of the phase diagram to show how this type of interaction
counterbalances the effects produced by a strong magnetic field. The most
important effects occur at intermediate and low temperatures affecting the
location of the critical end point as well as the region of first order chiral
transitions. When $G_V=0$ the presence of high magnetic fields ($eB \ge 10
m_\pi^2$) increases the density coexistence region with respect to the case
when $B$ and $G_V$ are absent while a decrease of this region is observed at
high $G_V$ values and vanishing magnetic fields. Another interesting aspect
observed at the low temperature region is that the usual decrease of the
coexistence chemical value (Inverse Magnetic Catalysis) at $G_V=0$ is highly
affected by the presence of the vector interaction which acts in the opposite
way. Our investigation also shows that the presence of a repulsive vector
interaction enhances the de Haas-van Alphen oscillations which, for very low
temperatures, take place at $eB \lesssim 6 m_\pi^2$. We observe that the
presence of a magnetic field, together with a repulsive vector interaction,
gives rise to a complex transition pattern since $B$ favors the appearance of
multiple solutions to the gap equation whereas $G_V$ turns some metastable
solutions into stable ones allowing for a cascade of transitions to occur.


title:
Investigation of gamma-ray sensitivity of neutron detectors based on
  thin converter films

abstract:
  Currently, many detector technologies for thermal neutron detection are in
development in order to lower the demand for the rare 3He gas. Gas detectors
with solid thin film neutron converters readout by gas proportional counter
method have been proposed as an appropriate choice for applications where large
area coverage is necessary. In this paper, we investigate the probability for
gamma-rays to generate a false count in a neutron measurement. Simulated
results are compared to measurement with a 10B thin film prototype and a 3He
detector. It is demonstrated that equal gamma-ray rejection to that of 3He
tubes is achieved with the new technology. The arguments and results presented
here are also applicable to gas detectors with converters other than solid 10B
layers, such as 6Li layers and 10BF3 gas.


title: Velocity spectra of quantum turbulence: experiments, numerics and models

abstract:
  Superfluid Turbulence is unusual and presents a challenge to fluid
dynamicists because it consists of two coupled, inter penetrating turbulent
fluids: the first is inviscid with quantised vorticity, the second is viscous
with continuous vorticity. Despite this double nature, the observed spectra of
the superfluid turbulent velocity at sufficiently large length scales are
similar to those o ordinary turbulence. We present experimental, numerical and
theoretical results which explain these similarities, and illustrate the limits
of our present understanding of superfluid turbulence at smaller scales.


title: An explicit calculation of the Ronkin function

abstract:
  We calculate the second order derivatives of the Ronkin function in the case
of an affine linear polynomial in three variables and give an expression of
them in terms of complete elliptic integrals and hypergeometric functions. This
gives a semi-explicit expression of the associated Monge-Amp\`ere measure, the
Ronkin measure.


title: In the heart of representable metric jets

abstract:
  Here, I aim to immerse myself in the heart of the metric jets, more precisely
of those which are representable, restricting myself to the main basic
concepts, while going deeper into some notions already mentionned in our
previous papers; this will give me the opportunity of lightening the previous
texts (including some proofs), while precising some ideas and giving new
examples (as the bifractal wave function) with a proof at the end of this
paper. Concerning the concrete examples found all along this paper: they play
the "starring role" in the understanding of our metric Differential Calculus!


title:
Computation of Losses in HTS Under the Action of Varying Magnetic Fields
  and Currents

abstract:
  Numerical modeling of superconductors is widely recognized as a powerful tool
for interpreting experimental results, understanding physical mechanisms and
predicting the performance of high-temperature superconductor (HTS) tapes,
wires and devices. This is especially true for ac loss calculation, since a
sufficiently low ac loss value is imperative to make these materials attractive
for commercialization. In recent years, a large variety of numerical models,
based on different techniques and implementations, have been proposed by
researchers around the world, with the purpose of being able to estimate ac
losses in HTSs quickly and accurately. This article presents a literature
review of the methods for computing ac losses in HTS tapes, wires and devices.
Technical superconductors have a relatively complex geometry (filaments, which
might be twisted or transposed, or layers) and consist of different materials.
As a result, different loss contributions exist. In this paper, we describe the
ways of computing such loss contributions, which include hysteresis losses,
eddy current losses, coupling losses, and losses in ferromagnetic materials. We
also provide an estimation of the losses occurring in a variety of power
applications.


title: A local duality principle for ideals of pure dimension

abstract:
  We prove that a certain cohomological residue associated to an ideal of pure
dimension is annihilated exactly by the ideal. The cohomological residue is
quite explicit and generalizes the classical local Grothendieck residue and the
cohomological residue of Passare.


title: Siegel modular forms and the gonality of curves

abstract:
  There is no stable Siegel modular form that vanishes on the trigonal locus in
every moduli space of curves.


title: The Glassey conjecture on asymptotically flat manifolds

abstract:
  We verify the 3-dimensional Glassey conjecture on asymptotically flat
manifolds $(R^{1+3}, g)$, where the metric $g$ is certain small space-time
perturbation of the flat metric, as well as the nontrapping asymptotically
Euclidean manifolds. Moreover, for radial asymptotically flat manifolds
$(R^{1+n}, g)$ with $n\ge 3$, we verify the Glassey conjecture in the radial
case. High dimensional wave equations with higher regularity are also
discussed. The main idea is to exploit local energy and KSS estimates with
variable coefficients, together with the weighted Sobolev estimates including
trace estimates.


title:
Approximation of sequences of symmetric matrices with the symmetric
  rank-one algorithm and applications

abstract:
  The symmetric rank-one update method is well-known in optimization for its
applications in the quasi-Newton algorithm. In particular, Conn, Gould, and
Toint proved in 1991 that the matrix sequence resulting from this method
approximates the Hessian of the minimized function. Expanding their idea, we
prove that the symmetric rank-one update algorithm can be used to approximate
any sequence of symmetric invertible matrices, thereby adding a variety of
applications to more general problems, such as the computation of constrained
geodesics in shape analysis imaging problems. We also provide numerical
simulations for the method and some of these applications.


title: Spectrum created by line defects in periodic structures

abstract:
  The spectrum of periodic differential operators typically exhibits a band-gap
structure. In this paper, we will consider perturbations to periodic
differential operators and investigate the spectrum the perturbation induces in
the gaps. More specifically, we consider the operator $$ L_0
=-\frac{1}{\eps_0(x,y,z)}\Delta $$ in $\R^3$ with $\eps_0$ periodic in all
three directions. The perturbation is introduced by replacing $\eps_0$ by
$\eps_0+\eps_1$ where we assume that $\eps_1$ is still periodic in one
direction, but compactly supported in the remaining two directions, creating a
line defect. We will show that even small perturbations $\eps_1$ lead to
additional spectrum in the spectral gaps of the unperturbed operator $L_0$ and
investigate some properties of the spectrum that is created.


title: Heat flow out of a compact manifold

abstract:
  We discuss the heat content asymptotics associated with the heat flow out of
a smooth compact manifold in a larger compact Riemannian manifold. Although
there are no boundary conditions, the corresponding heat content asymptotics
involve terms localized on the boundary. The classical pseudo-differential
calculus is used to establish the existence of the complete asymptotic series
and methods of invariance theory are used to determine the first few terms in
the asymptotic series in terms of geometric data. The operator driving the heat
process is assumed to be an operator of Laplace type.


title:
Electrically Detected Double Electron-Electron Resonance: Exchange
  Interaction of 31P Donors and Pb0 Defects at the Si/SiO2 Interface

abstract:
  We study the coupling of Pb0 dangling bond defects at the Si/SiO2 interface
and 31P donors in an epitaxial layer directly underneath using electrically
detected double electron-electron resonance (EDDEER). An exponential decay of
the EDDEER signal is observed, which is attributed to a broad distribution of
exchange coupling strengths J/2pi from 25 kHz to 3 MHz. Comparison of the
experimental data with a numerical simulation of the exchange coupling shows
that this range of coupling strengths corresponds to 31P-Pb0 distances ranging
from 14 nm to 20 nm.


title:
Highlighting Entanglement of Cultures via Ranking of Multilingual
  Wikipedia Articles

abstract:
  How different cultures evaluate a person? Is an important person in one
culture is also important in the other culture? We address these questions via
ranking of multilingual Wikipedia articles. With three ranking algorithms based
on network structure of Wikipedia, we assign ranking to all articles in 9
multilingual editions of Wikipedia and investigate general ranking structure of
PageRank, CheiRank and 2DRank. In particular, we focus on articles related to
persons, identify top 30 persons for each rank among different editions and
analyze distinctions of their distributions over activity fields such as
politics, art, science, religion, sport for each edition. We find that local
heroes are dominant but also global heroes exist and create an effective
network representing entanglement of cultures. The Google matrix analysis of
network of cultures shows signs of the Zipf law distribution. This approach
allows to examine diversity and shared characteristics of knowledge
organization between cultures. The developed computational, data driven
approach highlights cultural interconnections in a new perspective.


title: Information-Theoretic Security for the Masses

abstract:
  We combine interactive zero-knowledge protocols and weak physical layer
randomness properties to construct a protocol which allows bootstrapping an
IT-secure and PF-secure channel from a memorizable shared secret. The protocol
also tolerates failures of its components, still preserving most of its
security properties, which makes it accessible to regular users.


title: Cyclic extensions of Moufang loops induced by semi-automorphisms

abstract:
  It is well known that if a group G factorizes as G = NH where H\leq G and N
is normal in G then the group structure of G is determined by the subgroups H
and N, the intersection of N with H and how H acts on N with a homomorphism f :
H -> Aut(N). Here we generalize the idea by creating extensions using the
semi-automorphism group of N. We show that if G=NH is a Moufang loop, N is a
normal subloop, and H=<u> is a finite cyclic group of order coprime to three
then the binary operation of G depends only on the binary operation of N, the
intersection of N with H, and how u permutes the elements of N as a
semi-automorphism of N.


title: A Study of Library Migration in Java Software

abstract:
  Software intensively depends on external libraries whose relevance may change
during its life cycle. As a consequence, software developers must periodically
reconsider the libraries they depend on, and must think about \textit{library
migration}. To our knowledge, no existing study has been done to understand
library migration although it is known to be an expensive maintenance task. Are
library migrations frequent? For which software are they performed and when?
For which libraries? For what reasons? The purpose of this paper is to answer
these questions with the intent to help software developers that have to
replace their libraries. To that extent, we have performed a statistical
analysis of a large set of open source software to mine their library
migration. To perform this analysis we have defined an approach that identifies
library migrations in a pseudo-automatic fashion by analyzing the source code
of the software. We have implemented this approach for the Java programming
language and applied it on Java Open Source Software stored in large hosting
services. The main result of our study is that library migration is not a
frequent practice but depends a lot on the nature of the software as well as
the nature of the libraries.


title: Persian Heritage Image Binarization Competition (PHIBC 2012)

abstract:
  The first competition on the binarization of historical Persian documents and
manuscripts (PHIBC 2012) has been organized in conjunction with the first
Iranian conference on pattern recognition and image analysis (PRIA 2013). The
main objective of PHIBC 2012 is to evaluate performance of the binarization
methodologies, when applied on the Persian heritage images. This paper provides
a report on the methodology and performance of the three submitted algorithms
based on evaluation measures has been used.


title: Codes on Graphs: Fundamentals

abstract:
  This paper develops a fundamental theory of realizations of linear and group
codes on general graphs using elementary group theory, including basic group
duality theory. Principal new and extended results include: normal realization
duality; analysis of systems-theoretic properties of fragments of realizations
and their connections; "minimal = trim and proper" theorem for cycle-free
codes; results showing that all constraint codes except interface nodes may be
assumed to be trim and proper, and that the interesting part of a cyclic
realization is its "2-core;" notions of observability and controllability for
fragments, and related tests; relations between state-trimness and
controllability, and dual state-trimness and observability.


title: Towards Secure Two-Party Computation from the Wire-Tap Channel

abstract:
  We introduce a new protocol for secure two-party computation of linear
functions in the semi-honest model, based on coding techniques. We first
establish a parallel between the second version of the wire-tap channel model
and secure two-party computation. This leads us to our protocol, that combines
linear coset coding and oblivious transfer techniques. Our construction
requires the use of binary intersecting codes or $q$-ary minimal codes, which
are also studied in this paper.


title: Detection of screw threads in computed tomography 3D density fields

abstract:
  In this paper, a new method is proposed to automatically detect screw threads
in 3D density fields obtained from computed tomography measurement devices. The
described method can be used to automate many operations during screw thread
inspection process and drastically reduce operator's influence on the
measurement process resulting in lower measurement times and increased
repeatability.


title:
Dynamic Term Structure Modelling with Default and Mortality Risk: New
  Results on Existence and Monotonicity

abstract:
  This paper considers general term structure models like the ones appearing in
portfolio credit risk modelling or life insurance. We give a general model
starting from families of forward rates driven by infinitely many Brownian
motions and an integer-valued random measure, generalizing existing approaches
in the literature. Then we derive drift conditions which are equivalent to no
asymptotic free lunch on the considered market. Existence results are also
given. In practice, models possessing a certain monotonicity are favorable and
we study general conditions which guarantee this. The setup is illustrated with
some examples.


title:
Actuation, propagation, and detection of transverse magnetoelastic waves
  in ferromagnets

abstract:
  We study propagation of ultrasonic waves through a ferromagnetic medium with
special attention to the boundary conditions at the interface with an
ultrasonic actuator. In analogy to charge and spin transport in conductors, we
formulate the energy transport through the system as a scattering problem. We
find that the magneto-elastic coupling leads to a non-vanishing magnetic
(elastic) energy accompanying the acoustic (spin) waves with a resonantly
enhanced effect around the dispersion relation anti-crossing point. We
demonstrate the physics of excitation of magnetization dynamics via acoustic
waves injection around the ferromagnetic resonance frequency.


title: Active Contour Models for Manifold Valued Image Segmentation

abstract:
  Image segmentation is the process of partitioning a image into different
regions or groups based on some characteristics like color, texture, motion or
shape etc. Active contours is a popular variational method for object
segmentation in images, in which the user initializes a contour which evolves
in order to optimize an objective function designed such that the desired
object boundary is the optimal solution. Recently, imaging modalities that
produce Manifold valued images have come up, for example, DT-MRI images, vector
fields. The traditional active contour model does not work on such images. In
this paper, we generalize the active contour model to work on Manifold valued
images. As expected, our algorithm detects regions with similar Manifold values
in the image. Our algorithm also produces expected results on usual gray-scale
images, since these are nothing but trivial examples of Manifold valued images.
As another application of our general active contour model, we perform texture
segmentation on gray-scale images by first creating an appropriate Manifold
valued image. We demonstrate segmentation results for manifold valued images
and texture images.


title:
Lie algebras associated with quadratic forms and their applications to
  Ringel-Hall algebras

abstract:
  We define and investigate nilpotent Lie algebras associated with quadratic
forms. We also present their connections with Lie algebras and Ringel-Hall
algebras associated with representation directed algebras.


title: The existence of Hall polynomials for posets of finite prinjective type

abstract:
  We prove the existence of Hall polynomials for prinjective representations of
finite partially ordered sets of finite prinjective type. In Section 4 we
shortly discuss consequences of the existence of Hall polynomials, in
particular, we are able to define a generic Ringel-Hall algebra for prinjective
representations of posets of finite prinjective type.


title: Homotopy Groups of Diagonal Complements

abstract:
  For $X$ a connected finite simplicial complex we consider $\Delta^d(X,n)$ the
space of configurations of $n$ ordered points of $X$ such that no $d+1$ of them
are equal, and $B^d(X,n)$ the analogous space of configurations of unordered
points. These reduce to the standard configuration spaces of distinct points
when $d=1$. We describe the homotopy groups of $\Delta^d(X,n)$ (resp.
$B^d(X,n)$) in terms of the homotopy (resp. homology) groups of $X$ through a
range which is generally sharp. It is noteworthy that the fundamental group of
the configuration space $B^d(X,n)$ abelianizes as soon as we allow points to
collide (i.e. $d\geq 2$).


title: Acoustic plasmons in extrinsic free-standing graphene

abstract:
  An acoustic plasmon is predicted to occur, in addition to the conventional
two-dimensional (2D) plasmon, as the collective motion of a system of two types
of electronic carriers coexisting in the very same 2D band of extrinsic (doped
or gated) graphene. The origin of this novel mode resides in the strong
anisotropy that is present in the graphene band structure near the Dirac point.
This anisotropy allows for the coexistence of carriers moving with two distinct
Fermi velocities along the Gamma-K direction, which leads to two modes of
collective oscillation: one mode in which the two types of electrons oscillate
in phase with one another [this is the conventional 2D graphene plasmon, which
at long wavelengths (q->0) has the same dispersion, q^1/2, as the conventional
2D plasmon of a 2D free electron gas], and the other mode found here
corresponding to a low-frequency acoustic oscillation [whose energy exhibits at
long wavelengths a linear dependence on the 2D wavenumber q] in which the two
types of electrons oscillate out of phase. If this prediction is confirmed
experimentally, it will represent the first realization of acoustic plasmons
originated in the collective motion of a system of two types of carriers
coexisting within the very same band.


title:
Effective Scattering Cross-section in Lattice Thermal Conductivity
  Calculation with Differential Effective Medium Method

abstract:
  To further reduce the lattice thermal conductivity of thermoelectric
materials, the technique of embedding nano-inclusions into bulk matrix
materials, in addition to point defect scattering via alloying, was widely
applied. Differential Effective Medium (DEM) method was employed to calculate
two-phase heterogeneous systems. However, in most effective medium treatment,
the interface scattering of matrix phonons by embedded nanoparticle was
underestimated by adopting particle's projected area as scattering
cross-section. Herein, modified cross-section calculations, as well as grain
sizes dispersions, are applied in DEM, with the calculations then validated by
comparing with Monte-Carlo simulations and existing experimental data.
Predictions of lattice thermal conductivity reduction on in-situ formed Full
Heusler(FH)/Half Heusler(HH) nano/matrix system are discussed.


title: Impossibility of Spontaneously Rotating Time-Crystals: A No-Go Theorem

abstract:
  I present arguments indicating the impossibility of spontaneously rotating
quantum timecrystals, as recently proposed by Frank Wilczek [arXiv:1202.2539].
In particular, I prove a No-Go Theorem, rigorously ruling out the possibility
of spontaneous ground-state (or thermal equilibrium) rotation for a broad class
of systems.


title:
Cepheid theoretical models and observations in HST/WFC3 filters: the
  effect on the Hubble constant Ho

abstract:
  We present a complete theoretical scenario for classical Cepheids in the most
commonly used HST/WFC3 filters, going from optical (F555W, F606W and F814W) to
near-infrared (F160W) bands. The importance of such a study is related to the
recent release of new classical Cepheids observed with HST/WFC3 in 8 distant
galaxies where SNIa are hosted. These observations have posed sound constraints
to the current distance scale with uncertainties on the Hubble constant Ho
smaller than 3%. Our models explore a large range of metallicity and Helium
content, thus providing a robust and unique theoretical tool for describing
these new and future HST/WFC3 observations. As expected, the Period-Luminosity
(PL) relation in F160W filter is linear and slightly dependent on the
metallicity when compared with optical bands, thus it seems the most accurate
tool to constrain extragalactic distances with Cepheids. We compare the
pulsation properties of Cepheids observed with HST/WFC3-IR with our theoretical
scenario and we discuss the agreement with the predicted Instability Strip for
all the investigated galaxy samples including the case of NGC4258. Finally,
adopting our theoretical F160W PL relation for Z=0.02 and log P>1.0, we derive
new distance moduli. In particular, for NGC 4258, we derive a distance modulus
mu0 = 29.345 +- 0.004 mag with a sigma = 0.34 mag, which is in very good
agreement with the geometrical maser value. Moreover, using the obtained
distance moduli, we estimate the Hubble constant value, Ho=76.0 +- 1.9 km s-1
Mpc-1 in excellent agreement with the most recent literature values.


title:
Studies of single-photoelectron response and of performance in magnetic
  field of a H8500C-03 photomultiplier tube

abstract:
  We studied the single-photoelectron detection capabilities of a multianode
photomultiplier tube H8500C-03 and its performance in high magnetic field. Our
results show that the device can readily resolve signals at the single
photoelectron level making it suitable for photon detection in both threshold
and ring imaging Cerenkov detectors. We also found that a large longitudinal
magnetic field, up to 300 Gauss, induces a change in the relative output of at
most 55% for an edge pixel, and of at most 15% for a central pixel. The
H8500C-03 signal loss in transverse magnetic fields it is significantly more
pronounced than for the longitudinal case. Our studies of single photoelectron
reduction in magnetic fields point to the field induced misfocusing of the
photoelectron extracted from the photocathode as primary cause of signal loss.
With appropriate shielding this PMT could function in high magnetic field
environments.


title: Playing cooperatively with possibly treacherous partner

abstract:
  We investigate an alternative concept of Nash equilibrium, m-equilibrium,
which slightly resembles Harsanyi-Selten risk dominant equilibrium although it
is a different notion. M-equilibria provide nontrivial solutions of normal form
games as shown by comparison of the Prisoner's Dilemma with the Traveler's
Dilemma. They are also resistant on the deep iterated elimination of dominated
strategies.


title:
Continuum simulation of the discharge of the granular silo: a validation
  test for the mu(I)-visco-plastic flow law

abstract:
  Using both a continuum Navier-Stokes solver, with the mu(I)-flow-law
implemented to model the viscous behavior, and the discrete Contact Dynamics
algorithm, the discharge of granular silos is simulated in two dimensions from
the early stages of the discharge until complete release of the material. In
both cases, the Beverloo scaling is recovered. We first do not attempt
quantitative comparison, but focus on the qualitative behavior of velocity and
pressure at different locations in the flow. A good agreement is obtained in
the regions of rapid flows, while areas of slow creep are not entirely captured
by the continuum model. The pressure field shows a general good agreement. The
evolution of the free surface implies differences, however, the bulk
deformation is essentially identical in both approaches. The influence of the
parameters of the mu(I)-flow-law is systematically investigated, showing the
importance of the dependence on the inertial number I to achieve quantitative
agreement between continuum and discrete discharge. The general ability of the
continuum model to reproduce qualitatively the granular behavior is found to be
very encouraging.


title: Transferring the attoclock technique to velocity map imaging

abstract:
  Attosecond angular streaking measurements have revealed deep insights into
the timing of tunnel ionization processes of atoms in intense laser fields. So
far experiments of this type have been performed only with a cold-target
recoil-ion momentum spectrometer (COLTRIMS). Here, we present a way to apply
attosecond angular streaking experiments to a velocity map imaging spectrometer
(VMIS) with few-cycle pulses at a repetition rate of 10 kHz and a high
ionization yield per pulse. Three-dimensional photoelectron momentum
distributions from strong-field ionization of helium with an elliptically
polarized, sub-10-fs pulse were retrieved by tomographic reconstruction from
the momentum space electron images and used for the analysis in the
polarization plane.


title:
Compressive Coded Aperture Keyed Exposure Imaging with Optical Flow
  Reconstruction

abstract:
  This paper describes a coded aperture and keyed exposure approach to
compressive video measurement which admits a small physical platform, high
photon efficiency, high temporal resolution, and fast reconstruction
algorithms. The proposed projections satisfy the Restricted Isometry Property
(RIP), and hence compressed sensing theory provides theoretical guarantees on
the video reconstruction quality. Moreover, the projections can be easily
implemented using existing optical elements such as spatial light modulators
(SLMs). We extend these coded mask designs to novel dual-scale masks (DSMs)
which enable the recovery of a coarse-resolution estimate of the scene with
negligible computational cost. We develop fast numerical algorithms which
utilize both temporal correlations and optical flow in the video sequence as
well as the innovative structure of the projections. Our numerical experiments
demonstrate the efficacy of the proposed approach on short-wave infrared data.


title:
The physical nature of the 8 o'clock arc based on near-IR IFU
  spectroscopy with SINFONI

abstract:
  We present an analysis of near-infrared integral field unit spectroscopy of
the 8 o'clock arc, a gravitationally lensed Lyman break galaxy, taken with
SINFONI. We explore the shape of the spatially-resolved H\beta\ profile and
demonstrate that we can decompose it into three components that partially
overlap (spatially) but are distinguishable when we include dynamical
information. We use existing B and H imaging from the Hubble Space Telescope to
construct a rigorous lens model using a Bayesian grid based lens modelling
technique. We apply this lens model to the SINFONI data cube to construct the
de-lensed H\beta\ line-flux velocity and velocity dispersion maps of the
galaxy. We find that the 8 o'clock arc has a complex velocity field that is not
simply explained by a single rotating disk. The H\beta\ profile of the galaxy
shows a blue-shifted wing suggesting gas outflows of ~ 200 km s^{-1}. We
confirm that the 8 o'clock arc lies on the stellar mass--oxygen abundance--SFR
plane found locally, but it has nevertheless significantly different gas
surface density (a factor of 2--4 higher) and electron density in the ionized
gas (five times higher) from those in similar nearby galaxies, possibly
indicating a higher density interstellar medium for this galaxy.


title:
KASCADE-Grande measurements of energy spectra for elemental groups of
  cosmic rays

abstract:
  The KASCADE-Grande air shower experiment [W. Apel, et al. (KASCADE-Grande
collaboration), Nucl. Instrum. Methods A 620 (2010) 202] consists of, among
others, a large scintillator array for measurements of charged particles, Nch,
and of an array of shielded scintillation counters used for muon counting, Nmu.
KASCADE-Grande is optimized for cosmic ray measurements in the energy range 10
PeV to about 2000 PeV, where exploring the composition is of fundamental
importance for understanding the transition from galactic to extragalactic
origin of cosmic rays. Following earlier studies of the all-particle and the
elemental spectra reconstructed in the knee energy range from KASCADE data [T.
Antoni, et al. (KASCADE collaboration), Astropart. Phys. 24 (2005) 1], we have
now extended these measurements to beyond 200 PeV. By analysing the
two-dimensional shower size spectrum Nch vs. Nmu for nearly vertical events, we
reconstruct the energy spectra of different mass groups by means of unfolding
methods over an energy range where the detector is fully efficient. The
procedure and its results, which are derived based on the hadronic interaction
model QGSJET-II-02 and which yield a strong indication for a dominance of heavy
mass groups in the covered energy range and for a knee-like structure in the
iron spectrum at around 80 PeV, are presented. This confirms and further
refines the results obtained by other analyses of KASCADE-Grande data, which
already gave evidence for a knee-like structure in the heavy component of
cosmic rays at about 80 PeV [W. Apel, et al. (KASCADE-Grande collaboration),
Phys. Rev. Lett. 107 (2011) 171104].


title: The Importance of the Strategy in Backward Orbits

abstract:
  This work considers reversed evolution in dynamical systems. In particular,
asymptotic behavior of chaotic systems, when their orbits evolve backwards in
time. Reversed dynamics reveals important aspects of the trajectories, such as
a new necessary parameter. This is the strategy through which one orbit reaches
an original state in the past. As a result, it is found that backward orbits
exhibit sensitivity to the strategy. This gives additional evidence about the
unpredictability of the past


title: Restoration Ecology: Two-Sex Dynamics and Cost Minimization

abstract:
  We model a spatially detailed, two-sex population dynamics, to study the cost
of ecological restoration. We assume that cost is proportional to the number of
individuals introduced into a large habitat. We treat dispersal as homogeneous
diffusion. The local population dynamics depends on sex ratio at birth, and
allows mortality rates to differ between sexes. Furthermore, local density
dependence induces a strong Allee effect, implying that the initial population
must be sufficiently large to avert rapid extinction. We address three
different initial spatial distributions for the introduced individuals; for
each we minimize the associated cost, constrained by the requirement that the
species must be restored throughout the habitat. First, we consider spatially
inhomogeneous, unstable stationary solutions of the model's equations as
plausible candidates for small restoration cost. Second, we use numerical
simulations to find the smallest cluster size, enclosing a spatially
homogeneous population density, that minimizes the cost of assured restoration.
Finally, by employing simulated annealing, we minimize restoration cost among
all possible initial spatial distributions of females and males. For biased sex
ratios, or for a significant between-sex difference in mortality, we find that
sex-specific spatial distributions minimize the cost. But as long as the sex
ratio maximizes the local equilibrium density for given mortality rates, a
common homogeneous distribution for both sexes that spans a critical distance
yields a similarly low cost.


title:
Photo-Disintegration of the Iron Nucleus in Fractured Magnetite Rocks
  with Magnetostriction

abstract:
  There has been considerable interest in recent experiments on iron nuclear
disintegrations observed when rocks containing such nuclei are crushed and
fractured. The resulting nuclear transmutations are particularly strong for the
case of magnetite rocks, i.e. loadstones. We argue that the fission of the iron
nucleus is a consequence of photo-disintegration. The electro-strong coupling
between electromagnetic fields and nuclear giant dipole resonances are central
for producing observed nuclear reactions. The large electron energies produced
during the fracture of piezomagnetic rocks are closely analogous to the
previously discussed case of the fracture of piezoelectric rocks. In both cases
electro-weak interactions can produce neutrons and neutrinos from energetic
protons and electrons thus inducing nuclear transmutations. The electro-strong
condensed matter coupling discussed herein represents new many body collective
nuclear photo-disintegration effects.


title:
The Summary for Optimization of the Annular Coupled Structure
  Accelerating Module Physical Design for High Intensity Hadron Linac

abstract:
  The normal conducting Annular Coupled Structure (ACS) is applied for 190-400
MeV part of high intensity proton linac for the J-PARC. The ACS operating
frequency is 972 MHz. The J-PARC ACS is strongly based on the results of
previous investigations, especially results of Japan Hadron Project (JHP)
research program in KEK. However, the design was revised and optimized to meet
the requirements of reliability, operation efficiency and cost reduction. The
cells shape of accelerating cells was optimized in total energy range to have
high shunt impedance value together with the careful matching with the
decreased coupling cells. The design of the bridge coupler cells was optimized
to simplify mass production and shape of RF input cell together with matching
window were optimized for higher operational reliability. Collected and
adjusted all together, these modifications result in the significant effect.
The ACS module design doesn't lose to another possible accelerating structures
in RF parameters and dimensions. Previously developed for L-band ACS
fabrication technique is applied to 972 MHz ACS construction. The realized
solutions have the reserve for ACS module use with very high heat loading
during operations with 15% duty factor, the highest heat loading at present
time, as compared to accelerating modules with another normal conducting
accelerating structures, realized in hadron linacs. This report contains the
descriptions and explanations of changes in the ACS module physical design for
the J-PARC linac.


title: Information Spectrum Approach to the Source Channel Separation Theorem

abstract:
  A source-channel separation theorem for a general channel has recently been
shown by Aggrawal et. al. This theorem states that if there exist a coding
scheme that achieves a maximum distortion level d_{max} over a general channel
W, then reliable communication can be accomplished over this channel at rates
less then R(d_{max}), where R(.) is the rate distortion function of the source.
The source, however, is essentially constrained to be discrete and memoryless
(DMS). In this work we prove a stronger claim where the source is general,
satisfying only a "sphere packing optimality" feature, and the channel is
completely general. Furthermore, we show that if the channel satisfies the
strong converse property as define by Han & verdu, then the same statement can
be made with d_{avg}, the average distortion level, replacing d_{max}. Unlike
the proofs there, we use information spectrum methods to prove the statements
and the results can be quite easily extended to other situations.


title:
The exclusivity principle forbids sets of correlations larger than the
  quantum set

abstract:
  We show that the exclusivity (E) principle singles out the set of quantum
correlations associated to any exclusivity graph assuming the set of quantum
correlations for the complementary graph. Moreover, we prove that, for
self-complementary graphs, the E principle, by itself (i.e., without further
assumptions), excludes any set of correlations strictly larger than the quantum
set. Finally, we prove that, for vertex-transitive graphs, the E principle
singles out the maximum value for the quantum correlations assuming only the
quantum maximum for the complementary graph. This opens the door for testing
the impossibility of higher-than-quantum correlations in experiments.


title: Crossed products of Banach algebras. III

abstract:
  In earlier work a crossed product of a Banach algebra was constructed from a
Banach algebra dynamical system $(A,G,\alpha)$ and a class $\mathcal{R}$ of
continuous covariant representations, and its representations were determined.
In this paper we adapt the theory to the ordered context. We construct a
pre-ordered crossed product of a Banach algebra from a pre-ordered Banach
algebra dynamical system $(A,G,\alpha)$ and a given uniformly bounded class
$\mathcal{R}$ of continuous covariant representations of $(A,G,\alpha)$. If $A$
has a positive bounded approximate left identity and $\mathcal{R}$ consists of
non-degenerate continuous covariant representations, we establish a bijection
between the positive non-degenerate bounded representations of the pre-ordered
crossed product on pre-ordered Banach spaces with closed cones and the positive
non-degenerate $\mathcal{R}$-continuous covariant representations of
$(A,G,\alpha)$ on such spaces. Under mild conditions, we show that this
pre-ordered crossed product is the essentially unique pre-ordered Banach
algebra for which such a bijection exists. Finally, we study pre-ordered
generalized Beurling algebras. We show that they are bipositively topologically
isomorphic to pre-ordered crossed products of Banach algebras associated with
pre-ordered Banach algebra dynamical systems, and hence the general theory
allows us to describe their positive representations on pre-ordered Banach
spaces with closed cones.


title: A Method for Fast Diagonalization of a 2x2 or 3x3 Real Symmetric Matrix

abstract:
  A method is presented for fast diagonalization of a 2x2 or 3x3 real symmetric
matrix, that is determination of its eigenvalues and eigenvectors. The Euler
angles of the eigenvectors are computed. A small computer algebra program is
used to compute some of the identities, and a C++ program for testing the
formulas has been uploaded to arXiv.


title: An Exact Expression for Photon Polarization in Kerr Geometry

abstract:
  We analyze the transformation of the polarization of a photon propagating
along an arbitrary null geodesic in Kerr geometry. The motivation comes from
the problem of an observer trying to communicate quantum information to another
observer in Kerr spacetime by transmitting polarized photons. It is essential
that the observers understand the relationship between their frames of
reference and also know how the photon's polarization transforms as it travels
through Kerr spacetime. Existing methods to calculate the rotation of the
photon polarization (Faraday rotation) depend on choices of coordinate systems,
are algebraically complex and yield results only in the weak-field limit.
  We give a closed-form expression for a parallel propagated frame along an
arbitrary null geodesic using Killing-Yano theory, and thereby solve the
problem of parallel transport of the polarization vector in an intrinsic,
geometrically-motivated fashion. The symmetries of Kerr geometry are utilized
to obtain a remarkably compact expression for the geometrically induced phase
of the photon's polarization. We show that this phase vanishes on the
equatorial plane and the axis of symmetry.


title:
Anisotropic LMN dielectronic resonances from ratios of magnetic-dipole
  lines

abstract:
  Signatures of multi-keV LMN dielectronic resonances in highly-charged 3d^n
ions of tungsten were detected in the intensity ratios of extreme-ultraviolet
magnetic-dipole lines within ground configurations. The measurements were
performed with an electron beam ion trap at beam energies of about 6 keV.
Large-scale collisional-radiative modeling incorporating magnetic sublevels of
autoionizing levels showed the significance of anisotropy effects due to the
monodirectional propagation of the electron beam. The observation method allows
simultaneous resolved registration of dielectronic resonances from several
ions.


title:
Learning Trajectory Preferences for Manipulators via Iterative
  Improvement

abstract:
  We consider the problem of learning good trajectories for manipulation tasks.
This is challenging because the criterion defining a good trajectory varies
with users, tasks and environments. In this paper, we propose a co-active
online learning framework for teaching robots the preferences of its users for
object manipulation tasks. The key novelty of our approach lies in the type of
feedback expected from the user: the human user does not need to demonstrate
optimal trajectories as training data, but merely needs to iteratively provide
trajectories that slightly improve over the trajectory currently proposed by
the system. We argue that this co-active preference feedback can be more easily
elicited from the user than demonstrations of optimal trajectories, which are
often challenging and non-intuitive to provide on high degrees of freedom
manipulators. Nevertheless, theoretical regret bounds of our algorithm match
the asymptotic rates of optimal trajectory algorithms. We demonstrate the
generalizability of our algorithm on a variety of grocery checkout tasks, for
whom, the preferences were not only influenced by the object being manipulated
but also by the surrounding environment.\footnote{For more details and a
demonstration video, visit: \url{http://pr.cs.cornell.edu/coactive}}


title: Tight Lower Bound for Linear Sketches of Moments

abstract:
  The problem of estimating frequency moments of a data stream has attracted a
lot of attention since the onset of streaming algorithms [AMS99]. While the
space complexity for approximately computing the $p^{\rm th}$ moment, for
$p\in(0,2]$ has been settled [KNW10], for $p>2$ the exact complexity remains
open. For $p>2$ the current best algorithm uses $O(n^{1-2/p}\log n)$ words of
space [AKO11,BO10], whereas the lower bound is of $\Omega(n^{1-2/p})$ [BJKS04].
  In this paper, we show a tight lower bound of $\Omega(n^{1-2/p}\log n)$ words
for the class of algorithms based on linear sketches, which store only a sketch
$Ax$ of input vector $x$ and some (possibly randomized) matrix $A$. We note
that all known algorithms for this problem are linear sketches.


title:
Periodic magnetic structures generated by spin-polarized currents in
  nanostripes

abstract:
  The influence of a spin-polarized current on long ferromagnetic nanostripes
is studied numerically. The current flows perpendicularly to the stripe. The
study is based on the Landau-Lifshitz phenomenological equation with the
Slonczewski-Berger spin-torque term. The magnetization behavior is analyzed for
all range of the applied currents, up to the saturation. It is shown that the
saturation current is a nonmonotonic function of the stripe width. For a stripe
width increasing it approaches the saturation value for an infinite film. A
number of stable periodic magnetization structures are observed below the
saturation. Type of the periodical structure depends on the stripe width.
Besides the one-dimensional domain structure, typical for narrow wires, and the
two-dimensional vortex-antivortex lattice, typical for wide films, a number of
intermediate structures are observed, e.g. cross-tie and diamond state. For
narrow stripes an analytical analysis is provided.


title:
Thermal Conductivity of Core-Shell Based Nanocomposites for Enhancing
  Thermoelectric ZT

abstract:
  The differential effective medium method (DEM) is presented from a physical
viewpoint and employed to calculate the lattice thermal conductivity of
nano-bulk composites comprising core-shell particles. Extended from the
average-T-matrix single-particle approximation, DEM incorporates interparticle
effect essential for the study of core-shell nanocomposites (CSN).
Interparticle boundary scattering in addition to intraparticle boundary
scattering in CSN is found to add to the reduction of thermal conductivity of
nanocomposites. Thus, CSN hold the promise of improving the thermoelectric
dimensionless figure of merit ZT above that of monolithic nano-bulk phases. Si
and SiGe based CSN serve as illustrative examples.


title: Weak radiative corrections to dijet production at the LHC

abstract:
  We summarize the calculation of the weak corrections to dijet production at
hadron colliders, comprising tree-level effects of O(\alpha_s\alpha,\alpha^2)
and loop corrections of O(\alpha_s^2\alpha). Although suppressed by the small
value of the coupling constant \alpha, the weak radiative corrections can
become large in the high-energy domain due to the appearance of Sudakov-type
and other high-energy logarithms. Generally the corrections to the
transverse-momentum distributions are larger by approximately a factor of two
compared to the corresponding reach in the invariant-mass distributions,
because the invariant-mass distributions are not, unlike the k_T distributions,
dominated by the Sudakov regime at high scales. The electroweak tree-level
contributions are found to be of the same generic size as the loop corrections.


title:
Gravitational recoil in nonspinning black hole binaries: the span of
  test-mass results

abstract:
  We consider binary systems of coalescing, nonspinning, black holes of masses
$m_{1}$ and $m_{2}$ and show that the gravitational recoil velocity for any
mass ratio can be obtained accurately by extrapolating the waveform of the
test-mass limit case. The waveform obtained in the limit $m_1/m_2\ll 1$ via a
perturbative approach is extrapolated in $\nu= m_{1} m_{2}/(m_{1}+m_{2})^{2} $
multipole by multipole using the corresponding, analytically known,
leading-in-$\nu$ behavior. The final kick velocity computed from this
$\nu$-flexed waveform is written as $v(\nu)/c = 0.04457
\nu^2\sqrt{1-4\nu}\,(1-2.07106\nu + 3.93472\nu^2 -4.78404\nu^3+2.52040\nu^{4})$
and is compatible with the outcome of numerical relativity simulations


title: Effects of Gas Dynamics on Rapidly Collapsing Bubbles

abstract:
  The dynamics of rapidly collapsing bubbles are of great interest due to the
high degree of energy focusing that occurs withing the bubble. Molecular
dynamics provides a way to model the interior of the bubble and couple the gas
dynamics with the equations governing the bubble wall. While much theoretical
work has been done to understand how a bubble will respond to an external
force, the internal dynamics of the gas system are usually simplified greatly
in such treatments. This paper shows how the gas system dynamics affect bubble
collapse and illustrates what effects various modeling assumptions can have on
the motion of the bubble wall. In addition, we present a method of adaptively
partitioning space to improve the performance of collision intersection
calculations when using an energy dependent collision cross section.


title:
Effects of the rotating wave and secular approximations on
  non-Markovianity

abstract:
  We study the effect of the rotating-wave approximation (RWA) and the secular
approximation (SA) on the non-Markovian behavior in the spin-boson model at
zero-temperature. We find that both the RWA and SA lead to a dramatic reduction
in the observed non-Markovianity. In general, non-Markovian dynamics is
observed for the whole relaxation time of the system, whereas the RWA and SA
lead to such dynamics only on the short time scale of the environmental
correlation time. Thus, the RWA and SA are not necessarily justified in the
studies of non-Markovianity although they can estimate the state of the system
precisely. Furthermore, we derive an accurate analytical expression for the
non-Markovianity measure without the RWA or SA. This expression yields
important insight into the physics of the problem.


title: Solving Relational MDPs with Exogenous Events and Additive Rewards

abstract:
  We formalize a simple but natural subclass of service domains for relational
planning problems with object-centered, independent exogenous events and
additive rewards capturing, for example, problems in inventory control.
Focusing on this subclass, we present a new symbolic planning algorithm which
is the first algorithm that has explicit performance guarantees for relational
MDPs with exogenous events. In particular, under some technical conditions, our
planning algorithm provides a monotonic lower bound on the optimal value
function. To support this algorithm we present novel evaluation and reduction
techniques for generalized first order decision diagrams, a knowledge
representation for real-valued functions over relational world states. Our
planning algorithm uses a set of focus states, which serves as a training set,
to simplify and approximate the symbolic solution, and can thus be seen to
perform learning for planning. A preliminary experimental evaluation
demonstrates the validity of our approach.


title:
Classification of three-state Hamiltonians solvable by Coordinate Bethe
  Ansatz

abstract:
  We classify all Hamiltonians with rank 1 symmetry, acting on a periodic
three-state spin chain, and solvable through (generalisation of) the coordinate
Bethe ansatz (CBA). We obtain in this way four multi-parametric extensions of
the known 19-vertex Hamiltonians (such as Zamolodchikov-Fateev,
Izergin-Korepin, Bariev Hamiltonians). Apart from the 19-vertex Hamiltonians,
there exists 17-vertex and 14-vertex Hamiltonians that cannot be viewed as
subcases of the 19-vertex ones. In the case of 17-vertex Hamiltonian, we get a
generalization of the genus 5 special branch found by Martins, plus three new
ones. We get also two 14-vertex Hamiltonians.
  We solve all these Hamiltonians using CBA, and provide their spectrum,
eigenfunctions and Bethe equations. A special attention is made to provide the
specifications of our multi-parametric Hamiltonians that give back known
Hamiltonians.


title: Thermally activated conductance in arrays of small Josephson junctions

abstract:
  We present measurements of the temperature-dependent conductance for series
arrays of small-capacitance SQUIDs. At low bias voltages, the arrays exhibit a
strong Coulomb blockade, which we study in detail as a function of temperature
and Josephson energy $E_J$. We find that the zero-bias conductance is well
described by thermally activated charge transport with the activation energy on
the order of $\Lambda E_C$, where $\Lambda$ is the charge screening length in
the array and $E_C$ is the charging energy of a single SQUID.


title: A half-space theorem for ideal Scherk graphs in $M\times\mathbb R$

abstract:
  We prove a half-space theorem for an ideal Scherk graph $\Sigma\subset
M\times\mathbb R$ over a polygonal domain $D\subset M,$ where $M$ is a Hadamard
surface whose curvature is bounded above by a negative constant. More
precisely, we show that a properly immersed minimal surface contained in
$D\times\mathbb R$ and disjoint from $\Sigma$ is a translate of $\Sigma.$


title:
Magnetic field-enhanced spin freezing in YBa2Cu3O6.45 at the verge of
  the competition between superconductivity and charge order

abstract:
  Using 63Cu NMR, we establish that the enhancement of spin order by a magnetic
field H in YBa2Cu3O6.45 arises from a competition with superconductivity
because the effect occurs for H perpendicular, but not parallel, to the CuO2
planes, and it persists up to field values comparable to Hc2. We also find that
the spin-freezing has a glassy nature and that the frozen state onsets at a
temperature which is independent of the magnitude of H. These results, together
with the presence of a competing charge-ordering instability at nearby doping
levels, are strikingly parallel to those previously obtained in La-214. This
suggests a universal interpretation of magnetic field effects in underdoped
cuprates where the enhancement of spin order by the field may not be the
primary phenomenon but rather a byproduct of the competition between
superconductivity and charge order. Low-energy spin fluctuations are manifested
up to relatively high temperatures where they partially mask the signature of
the pseudogap in 1/T1 data of planar Cu sites.


title: The pole of the fermion propagator in a general class of gauges

abstract:
  We study the behavior of the pole of the fermion propagator, in QED in
$n$-dimensions, in a general class of gauges which interpolate between the
covariant, the axial and the Coulomb gauges. We use Nielsen identities,
following from the BRST invariance of the theory, to determine the gauge
variation of the fermion two point function in this general class of gauges.
This allows us to show directly and in a simple manner, to all orders in
perturbation theory, that in the absence of infrared divergences and mass shell
singularities, the fermion pole mass is gauge independent.


title: Pad\'e Approximants and Resonance Poles

abstract:
  Based on the mathematically well defined Pad\'e Theory, a theoretically safe
new procedure for the extraction of the pole mass and width of a resonance is
proposed. In particular, thanks to the Montessus de Ballore theorem we are able
to unfold the Second Riemann Sheet of an amplitude to search for the position
of the resonant pole in the complex plane. The method is systematic and
provides a model-independent treatment of the prediction and the corresponding
errors of the approximation.


title: Isospin dependence of nucleon Correlations in ground state nuclei

abstract:
  The dispersive optical model (DOM) as presently implemented can investigate
the isospin (nucleon asymmetry) dependence of the Hartree-Fock-like potential
relevant for nucleons near the Fermi energy. Data constraints indicate that a
Lane-type potential adequately describes its asymmetry dependence. Correlations
beyond the mean-field can also be described in this framework, but this
requires an extension that treats the non-locality of the Hartree-Fock-like
potential properly. The DOM has therefore been extended to properly describe
ground-state properties of nuclei as a function of nucleon asymmetry in
addition to standard ingredients like elastic nucleon scattering data and level
structure. Predictions of nucleon correlations at larger nucleon asymmetries
can then be made after data at smaller asymmetries constrain the potentials
that represent the nucleon self-energy. A simple extrapolation for Sn isotopes
generates predictions for increasing correlations of minority protons with
increasing neutron number. Such predictions can be investigated by performing
experiments with exotic beams. The predicted neutron properties for the double
closed-shell 132Sn nucleus exhibit similar correlations as those in 208Pb.
Future relevance of these studies for understanding the properties of all
nucleons, including those with high momentum, and the role of three-body forces
in nuclei are briefly discussed. Such an implementation will require a proper
treatment of the non-locality of the imaginary part of the potentials and a
description of high-momentum nucleons as experimentally constrained by the
(e,e'p) reactions performed at Jefferson Lab.


title:
Pressure induced amorphization and collapse of magnetic order in type-I
  clathrate Eu8Ga16Ge30

abstract:
  We investigate the low temperature structural and electronic properties of
the type-I clathrate Eu8Ga16Ge30 under pressure using x-ray powder diffraction
(XRD), x-ray absorption near-edge structure (XANES) and x-ray magnetic circular
dichroism (XMCD) techniques. The XRD measurements reveal a transition to an
amorphous phase above 18 GPa. Unlike previous reports on other clathrate
compounds, no volume-collapse is observed prior to the crystalline-amorphous
phase transition which takes place when the unit cell volume is reduced to 81%
of its ambient pressure value. Fits of the pressure-dependent relative volume
to a Murnaghan equation of state (EOS) yield a bulk modulus B0 = 65+-3 GPa and
a pressure derivative B'0 = 3.3+-0.5. The Eu L2-edge XMCD data shows quenching
of the magnetic order at the crystalline-amorphous phase transition. The XANES
spectra indicate the persistence of Eu2+ valency state up to 22 GPa, therefore
the suppression of XMCD intensity is due to the loss of magnetic order as a
result of frustrated exchange interactions in the amorphous phase, and not due
to quenching of local moments. When compared with other clathrates, the results
point to the importance of guest ion-cage interactions in determining the
mechanical stability of the framework structure and the critical pressure for
amorphization. Finally, the crystalline structure is not found to recover after
pressure release, resulting in a novel amorphous material that is at least
metastable at ambient pressure and temperature.


title: Fast Software Polar Decoders

abstract:
  Among error-correcting codes, polar codes are the first to provably achieve
channel capacity with an explicit construction. In this work, we present
software implementations of a polar decoder that leverage the capabilities of
modern general-purpose processors to achieve an information throughput in
excess of 200 Mbps, a throughput well suited for software-defined-radio
applications. We also show that, for a similar error-correction performance,
the throughput of polar decoders both surpasses that of LDPC decoders targeting
general-purpose processors and is competitive with that of state-of-the-art
software LDPC decoders running on graphic processing units.


title: Simplicity and exceptionality of syzygy bundles over P^n

abstract:
  In this work we will prove results that ensure the simplicity and the
exceptionality of vector bundles which are defined by the splitting of pure
resolutions. We will call such objects syzygy bundles.


title:
A Bayesian approach to inferring the phylogenetic structure of
  communities from metagenomic data

abstract:
  Metagenomics provides a powerful new tool set for investigating evolutionary
interactions with the environment. However, an absence of model-based
statistical methods means that researchers are often not able to make full use
of this complex information. We present a Bayesian method for inferring the
phylogenetic relationship among related organisms found within metagenomic
samples. Our approach exploits variation in the frequency of taxa among samples
to simultaneously infer each lineage haplotype, the phylogenetic tree
connecting them, and their frequency within each sample. Applications of the
algorithm to simulated data show that our method can recover a substantial
fraction of the phylogenetic structure even in the presence of strong mixing
among samples. We provide examples of the method applied to data from green
sulfur bacteria recovered from an Antarctic lake, plastids from mixed
Plasmodium falciparum infections, and virulent Neisseria meningitidis samples.


title: Linear polarization of rapidly rotating ultracool dwarfs

abstract:
  Aims. We aim at studying the near infrared linear polarization signal of
rapidly rotating ultracool dwarfs with spectral types ranging from M7 through
T2 and projected rotational velocities vsini >= 30 km s^{-1}. All these dwarfs
are believed to have dusty atmospheres and oblate shapes, an appropriate
scenario to produce measurable linear polarization of the continuum light.\\
Methods. Linear polarimetric images were collected in the J-band for a sample
of 18 fast-rotating ultracool dwarfs, five of which were also observed in the
Z-band using the LIRIS spectrograph on the Cassegrain focus of the 4.2-m
William Herschel Telescope. The measured median uncertainty in the linear
polarization degree is +/-0.13% for our sample, which allowed us to detect
polarization signatures above ~0.39% with a confidence of >=3\sigma.\\ Results.
About 40+/-15% of the sample is linearly polarized in the Z- and J-bands. All
positive detections have linear polarization degrees ranging from 0.4% to 0.8%
in both filters independently of spectral type and spectroscopic rotational
velocity. However, simple statistics point at the fastest rotators (vsini >=60
km s^{-1}) having a larger fraction of positive detections and a larger
averaged linear polarization degree than the moderately rotating dwarfs
(vsini=30--60 km s^{-1}). Our data suggest little linear polarimetric
variability on short time scales (i.e., observations separated by a few ten
rotation periods), and significant variability on long time scales (i.e.,
hundred to thousand rotation cycles), supporting the presence of "long-term
weather" in ultracool dwarf atmospheres.


title:
Hamiltonian-based impurity solver for nonequilibrium dynamical
  mean-field theory

abstract:
  We derive an exact mapping from the action of nonequilibrium dynamical
mean-field theory (DMFT) to a single-impurity Anderson model (SIAM) with
time-dependent parameters, which can be solved numerically by exact
diagonalization. The representability of the nonequilibrium DMFT action by a
SIAM is established as a rather general property of nonequilibrium Green
functions. We also obtain the nonequilibrium DMFT equations using the cavity
method alone. We show how to numerically obtain the SIAM parameters using
Cholesky or eigenvector matrix decompositions. As an application, we use a
Krylov-based time propagation method to investigate the Hubbard model in which
the hopping is switched on, starting from the atomic limit. Possible future
developments are discussed.


title: An Effect System for Algebraic Effects and Handlers

abstract:
  We present an effect system for core Eff, a simplified variant of Eff, which
is an ML-style programming language with first-class algebraic effects and
handlers. We define an expressive effect system and prove safety of operational
semantics with respect to it. Then we give a domain-theoretic denotational
semantics of core Eff, using Pitts's theory of minimal invariant relations, and
prove it adequate. We use this fact to develop tools for finding useful
contextual equivalences, including an induction principle. To demonstrate their
usefulness, we use these tools to derive the usual equations for mutable state,
including a general commutativity law for computations using non-interfering
references. We have formalized the effect system, the operational semantics,
and the safety theorem in Twelf.


title: Local-entire cyclic cocycles for graded quantum field nets

abstract:
  In a recent paper we studied general properties of super-KMS functionals on
graded quantum dynamical systems coming from graded translation-covariant
quantum field nets over R, and we carried out a detailed analysis of these
objects on certain models of superconformal nets. In the present article we
show that these locally bounded functionals give rise to local-entire cyclic
cocycles (generalized JLO cocycles), which are homotopy-invariant for a
suitable class of perturbations. Thus we can associate meaningful
noncommutative geometric invariants to those graded quantum dynamical systems.


title: Data reliability in complex directed networks

abstract:
  The availability of data from many different sources and fields of science
has made it possible to map out an increasing number of networks of contacts
and interactions. However, quantifying how reliable these data are remains an
open problem. From Biology to Sociology and Economy, the identification of
false and missing positives has become a problem that calls for a solution. In
this work we extend one of newest, best performing models -due to Guimera and
Sales-Pardo in 2009- to directed networks. The new methodology is able to
identify missing and spurious directed interactions, which renders it
particularly useful to analyze data reliability in systems like trophic webs,
gene regulatory networks, communication patterns and social systems. We also
show, using real-world networks, how the method can be employed to help
searching for new interactions in an efficient way.

categories: physics.soc-ph cond-mat.stat-mech physics.bio-ph q-bio.MN


title: Novae Ejecta as Discrete Adiabatically Expanding Globules

abstract:
  Available data for novae show that the X-ray and visible spectral regions
correlate with each other as they evolve. Large differences in ionization exist
simultaneously in the two wavelength regimes, and a straightforward model is
proposed that explains the characteristics observed in both spectral regimes.
Its key features are (1) ejected blobs of very high density gas from the white
dwarf that expand to create within each clump a wide range of emitting density,
ionization, and velocity, and (2) a more homogeneous circumbinary envelope of
gas that is produced by secondary star mass loss. The relative mass loss rates
from the two stars determine whether the He/N or the Fe II visible spectrum
predominates during decline, when hard X-rays are detected, and when the white
dwarf can be detected as a super soft X-ray source.


title: Flat histogram diagrammatic Monte Carlo method

abstract:
  The diagrammatic Monte Carlo (Diag-MC) method is a numerical technique which
samples the entire diagrammatic series of the Green's function in quantum
many-body systems. In this work, we incorporate the flat histogram principle in
the diagrammatic Monte method and we term the improved version "Flat Histogram
Diagrammatic Monte Carlo" method. We demonstrate the superiority of the method
over the standard Diag-MC in extracting the long-imaginary-time behavior of the
Green's function, without incorporating any a priori knowledge about this
function, by applying the technique to the polaron problem


title: When amplification with weak values fails to suppress technical noise

abstract:
  The application of postselection to a weak quantum measurement leads to the
phenomenon of weak values. Expressed in units of the measurement strength, the
displacement of a quantum coherent measuring device is ordinarily bounded by
the eigenspectrum of the measured observable. Postselection can enable an
interference effect that moves the average displacement far outside this range,
bringing practical benefits in certain situations. Employing the Fisher
information metric, we argue that the amplified displacement offers no
fundamental metrological advantage, due to the necessarily reduced probability
of success. Our understanding of metrological advantage is the possibility of a
lower uncertainty in the estimate of an unknown parameter with a large number
of trials. We analyze a situation in which the detector is pixelated with a
finite resolution, and in which the detector is afflicted by random
displacements: imperfections which degrade the fundamental limits of parameter
estimation. Surprisingly, weak-value amplification is no more robust to them
than a technique making no use of the amplification effect brought about by a
final, postselected measurement.


title: On involutive cluster automorphisms

abstract:
  We construct a special embedding of the translation quiver $\mathbb{Z}Q$ in
the three-dimensional affine space $\mathbb{R}^{3}$ where $Q$ is a finite
connected acyclic quiver and $\mathbb{Z}Q$ contains a local slice whose quiver
is isomorphic to the opposite quiver $Q^{op}$ of $Q.$ Via this embedding, we
show that there exists an involutive anti-automorphism of the translation
quiver $\mathbb{Z}Q.$ As an immediate consequence, we characterize explicitly
the group of cluster automorphisms of the cluster algebras of seed $(X,Q)$,
where $Q$ and $Q^{op}$ are mutation equivalent.


title: Mapping Dirac gaugino masses

abstract:
  We investigate the mapping of Dirac gaugino masses through regions of strong
coupling, focussing on SQCD with an adjoint. These models have a well-known
Kutasov duality, under which a weakly coupled electric UV description can flow
to a different weakly coupled magnetic IR description. We provide evidence to
show that Dirac gaugino mass terms map as lim_{mu->infty} mD/(g kappa^{1/(k+1}}
= lim_{mu->0} tilde{mD}/(tilde{g} tilde{kappa}^{1/(k+1}} under such a flow,
where the coupling kappa appears in the superpotential of the canonically
normalised theory as W \supset kappa X^{k+1}. This combination is an
RG-invariant to all orders in perturbation theory, but establishing the mapping
in its entirety is not straightforward because Dirac masses are not the
spurions of holomorphic couplings in the N=1 theory. To circumvent this, we
first demonstrate that deforming the Kutasov theory can make it flow to an N=2
theory with parametrically small N=1 deformations. Using harmonic superspace
techniques we then show that the N=1 deformations can be recovered from
electric and magnetic FI-terms that break N=2 -> N=1, and also show that pure
Dirac mass terms can be induced by the same mechanism. We then find that the
proposed RG-invariant is indeed preserved under N=2 duality, and thence along
the flow to the dual N=1 Kutasov theories. Possible phenomenological
applications are discussed.


title: Eclipsing Binary Stars in the OGLE-III Galactic Disk Fields

abstract:
  We present the analysis of 11 589 eclipsing binary stars identified in
twenty-one OGLE-III Galactic disk fields toward constellations of Carina,
Centaurus, and Musca. All eclipsing binaries but 402 objects are new
discoveries. The binaries have out-of-eclipse brightness between I=12.5 mag and
I=21 mag. The completeness of the catalog is estimated at a level of about 75%.
Comparison of the orbital period distribution for the OGLE-III disk binaries
with systems detected in other recent large-scale Galactic surveys shows the
maximum around 0.40 d and an almost flat distribution between 0.5 d and 2.5 d,
indepedent of population. Ten doubly eclipsing systems and one
eclipsing-ellipsoidal object were found among thousands of variables. Nine of
them are candidates for quadruple systems. We also identify ten eclipsing
subdwarf-B type binary stars and numerous eclipsing RS CVn type variables. All
objects reported in this paper are part of the OGLE-III Catalog of Variable
Stars.


title:
How to Distinguish between Cloudy Mini-Neptunes and
  Water/Volatile-Dominated Super-Earths

abstract:
  One of the most profound questions about the newly discovered class of
low-density super-Earths is whether these exoplanets are predominately
H2-dominated mini-Neptunes or volatile-rich worlds with gas envelopes dominated
by H2O, CO2, CO, CH4, or N2. Transit observations of the super-Earth GJ 1214b
rule out a cloud-free H2-dominated atmosphere, but are not able to determine
whether the lack of deep spectral features is due to high-altitude clouds or
the presence of a high mean molecular mass atmosphere. Here, we demonstrate
that one can unambiguously distinguish between cloudy mini-Neptunes and
volatile-dominated worlds based on the differences in the wing steepness and
relative depths of water absorption features in moderate-resolution NIR
transmission spectra (R~100). In a numerical retrieval study, we show for GJ
1214b that an unambiguous distinction between a cloudy H2-dominated atmosphere
and cloud-free H2 atmosphere will be possible if the uncertainties in the
spectral transit depth measurements can be reduced by a factor of ~3 compared
to the published HST WFC3 and VLT transit observations. We argue that the
required precision for the distinction may be achievable with currently
available instrumentation by stacking 10-15 transit observations. We provide a
scaling law that scales our quantitative results to other transiting
super-Earths and Neptunes such as HD 97658b, 55 Cnc e, and GJ 436b. The
analysis is performed using an improved version of our Bayesian atmospheric
retrieval framework. The new framework not only constrains the gas composition
and cloud/haze parameters, but also determines our confidence in having
detected molecules and cloud/haze species through Bayesian model comparison.
Using the Bayesian tool, we demonstrate quantitatively that the subtle transit
depth variation in the Berta et al. (2012) data is not sufficient to claim the
detection of water absorption.


title: Observation of the SU(4) Kondo state in a double quantum dot

abstract:
  Central to condensed matter physics are quantum impurity models, which
describe how a local degree of freedom interacts with a continuum.
Surprisingly, these models are often universal in that they can quantitatively
describe many outwardly unrelated physical systems. Here we develop a double
quantum dot-based experimental realization of the SU(4) Kondo model, which
describes the maximally symmetric screening of a local four-fold degeneracy. As
demonstrated through transport measurements and detailed numerical
renormalization group calculations, our device affords exquisite control over
orbital and spin physics. Because the two quantum dots are coupled only
capacitively, we can achieve orbital state- or "pseudospin"-resolved bias
spectroscopy, providing intimate access to the interplay of spin and orbital
Kondo effects. This cannot be achieved in the few other systems realizing the
SU(4) Kondo state.


title:
The International Linear Collider Technical Design Report - Volume 1:
  Executive Summary

abstract:
  The International Linear Collider Technical Design Report (TDR) describes in
four volumes the physics case and the design of a 500 GeV centre-of-mass energy
linear electron-positron collider based on superconducting radio-frequency
technology using Niobium cavities as the accelerating structures. The
accelerator can be extended to 1 TeV and also run as a Higgs factory at around
250 GeV and on the Z0 pole. A comprehensive value estimate of the accelerator
is give, together with associated uncertainties. It is shown that no
significant technical issues remain to be solved. Once a site is selected and
the necessary site-dependent engineering is carried out, construction can begin
immediately. The TDR also gives baseline documentation for two high-performance
detectors that can share the ILC luminosity by being moved into and out of the
beam line in a "push-pull" configuration. These detectors, ILD and SiD, are
described in detail. They form the basis for a world-class experimental
programme that promises to increase significantly our understanding of the
fundamental processes that govern the evolution of the Universe.


title:
The International Linear Collider Technical Design Report - Volume 3.II:
  Accelerator Baseline Design


title:
The International Linear Collider Technical Design Report - Volume 4:
  Detectors


title:
The Sloan digital sky survey data release 7 spectroscopic m dwarf
  catalog iii: The spatial dependence of magnetic activity in the galaxy

abstract:
  We analyze the magnetic activity of 59,318 M dwarfs from the Sloan Digital
Sky Survey (SDSS) Data Release 7. This analysis explores the spatial
distribution of M dwarf activity as a function of both vertical distance from
the Galactic plane (Z) and planar distance from the Galactic center (R). We
confirm the established trends of decreasing magnetic activity (as measured by
H-alpha emission) with increasing distance from the mid-plane of the disk and
find evidence for a trend in Galactocentric radius. We measure a non-zero
radial gradient in the activity fraction in our analysis of stars with spectral
types dM3 and dM4. The activity fraction increases with R and can be explained
by a decreasing mean stellar age with increasing distance from the Galactic
center.


title: Bipartite Field Theories from D-Branes

abstract:
  We develop tools for determining the gauge theory resulting from a
configuration of Type IIB D3-branes probing a non-compact, toric Calabi-Yau
3-fold, in the presence of additional flavor D7-branes with general embeddings.
Two main ingredients of our approach are dimer models and mirror symmetry.
D7-branes with general embeddings are obtained by recombination of elementary
D7-brane constituents. These tools are then used to engineer a large set of
Bipartite Field Theories, a class of 4d, N=1 quantum field theories defined by
bipartite graphs on bordered Riemann surfaces. Several explicit examples,
including infinite families of models, associated to both planar and non-planar
graphs are presented.


title: The (galaxy-wide) IMF in giant elliptical galaxies: From top to bottom

abstract:
  Recent evidence based independently on spectral line strengths and dynamical
modelling point towards a non-universal stellar Initial Mass Function (IMF),
probably implying an excess of low-mass stars in elliptical galaxies with a
high velocity dispersion. Here we show that a time-independent bottom-heavy IMF
is compatible neither with the observed metal-rich populations found in giant
ellipticals nor with the number of stellar remnants observed within these
systems. We suggest a two-stage formation scenario involving a time-dependent
IMF to reconcile these observational constraints. In this model, an early
strong star-bursting stage with a top-heavy IMF is followed by a more prolonged
stage with a bottom-heavy IMF. Such model is physically motivated by the fact
that a sustained high star formation will bring the interstellar medium to a
state of pressure, temperature and turbulence that can drastically alter the
fragmentation of the gaseous component into small clumps, promoting the
formation of low-mass stars. This toy model is in good agreement with the
different observational constrains on massive elliptical galaxies, such as age,
metallicity, alpha-enhancement, M/L, or the mass fraction of the stellar
component in low-mass stars.


title:
Chronos: A NIR spectroscopic galaxy survey. From the formation of
  galaxies to the peak of activity

abstract:
  Chronos is our response to ESA's call for white papers to define the science
for the future L2, L3 missions. Chronos targets the formation and evolution of
galaxies, by collecting the deepest NIR spectroscopic data, from the formation
of the first galaxies at z~10 to the peak of formation activity at z~1-3. The
strong emission from the atmospheric background makes this type of survey
impossible from a ground-based observatory. The spectra of galaxies represent
the equivalent of a DNA fingerprint, containing information about the past
history of star formation and chemical enrichment. The proposed survey will
allow us to dissect the formation process of galaxies including the timescales
of quenching triggered by star formation or AGN activity, the effect of
environment, the role of infall/outflow processes, or the connection between
the galaxies and their underlying dark matter haloes. To provide these data,
the mission requires a 2.5m space telescope optimised for a campaign of very
deep NIR spectroscopy. A combination of a high multiplex and very long
integration times will result in the deepest, largest, high-quality
spectroscopic dataset of galaxies from z=1 to 12, spanning the history of the
Universe, from 400 million to 6 billion years after the big bang, i.e. covering
the most active half of cosmic history.


title: The Mass-Metallicity Relation Of A Z~2 Protocluster With MOSFIRE

abstract:
  We present Keck/MOSFIRE observations of the role of environment in the
formation of galaxies at z~2. Using K-band spectroscopy of H-alpha and [N II]
emission lines, we have analyzed the metallicities of galaxies within and
around a z=2.3 protocluster discovered in the HS1700+643 field. Our main sample
consists of 23 protocluster and 20 field galaxies with estimates of stellar
masses and gas-phase metallicities based on the N2 strong-line metallicity
indicator. With these data we have examined the mass-metallicity relation (MZR)
with respect to environment at z~2. We find that field galaxies follow the
well-established trend between stellar mass and metallicity, such that more
massive galaxies have larger metallicities. The protocluster galaxies, however,
do not exhibit a dependence of metallicity on mass, with the low-mass
protocluster galaxies showing an enhancement in metallicity compared to field
galaxies spanning the same mass range. A comparison with galaxy formation
models suggests that the mass-dependent environmental trend we observed can be
qualitatively explained in the context of the recycling of "momentum-driven"
galaxy wind material. Accordingly, winds are recycled on a shorter timescale in
denser environments, leading to an enhancement in metallicity at fixed mass for
all but the most massive galaxies. Future hydrodynamical simulations of z~2
overdensities matching the one in the HS1700 field will be crucial for
understanding the origin of the observed environmental trend in detail.


title:
EVN observations of 6.7-GHz methanol maser polarization in massive
  star-forming regions II. First statistical results

abstract:
  Magnetic fields have only recently been included in theoretical simulations
of high-mass star formation. The simulations show that magnetic fields play an
important role in the formation and dynamics of molecular outflows. Masers, in
particular 6.7-GHz CH3OH masers, are the best probes of the magnetic field
morphologies around massive young stellar objects on the smallest scales of
10-100 AU. This paper focuses on 4 massive young stellar objects,
IRAS06058+2138-NIRS1, IRAS22272+6358A, S255-IR, and S231, which complement our
previous 2012 sample (the first EVN group). From all these sources, molecular
outflows have been detected in the past. Seven of the European VLBI Network
antennas were used to measure the linear polarization and Zeeman-splitting of
the 6.7-GHz CH3OH masers in the star-forming regions in this second EVN group.
We detected a total of 128 CH3OH masing cloudlets. Fractional linear
polarization (0.8%-11.3%) was detected towards 18% of the CH3OH masers in our
sample. The linear polarization vectors are well ordered in all the massive
young stellar objects. We measured significant Zeeman-splitting in
IRAS06058+2138-NIRS1 (DVz=3.8+/-0.6 m/s) and S255-IR (DVz=3.2+/-0.7 m/s). By
considering the 20 massive young stellar objects towards which the morphology
of magnetic fields was determined by observing 6.7-GHz CH3OH masers in both
hemispheres, we find no evident correlation between the linear distributions of
CH3OH masers and the outflows or the linear polarization vectors. On the other
hand, we present first statistical evidence that the magnetic field (on scales
10-100 AU) is primarily oriented along the large-scale outflow direction.
Moreover, we empirically find that the linear polarization fraction of
unsaturated CH3OH masers is P_l<4.5%.


title: Measuring the gas clumping in Abell 133

abstract:
  This paper continues a series in which we developed a non-parametric method
to measure inhomogeneities in the gas distribution from X-ray observations of
galaxy clusters. In this work, we apply our method to Chandra X-ray
observations of Abell 133 and present the determination of the gas clumping
factor from X-ray cluster data. We find that the gas clumping factor in Abell
133 increases with radius and reaches $\sim 2-3$ at $0.9\,R_{200}$. This is in
good agreement with the predictions of hydrodynamical simulations and our
previous determination. We then observe a general trend of steepening in the
radial profiles of the clumping-corrected gas density beyond $0.3\, R_{200}$,
with a logarithmic slope of $\sim 2.6$ at $0.9\,R_{200}$. The observed density
profiles appear to be flatter compared to simulations, but in agreement with
previous observational findings. In addition, we observe that the measured
temperature decreases steadily with radius toward the outskirts of A133, while
the entropy increases monotonically with radius, gently flattening in the outer
volumes. With respect to theoretical predictions from pure gravitational
collapse, the results presented here point to an entropy excess in the central
regions, which extends out to large radii. These results suggest that gas
inhomogeneities should be treated properly when interpreting X-ray measurements
in the envelope of galaxy clusters. We finally discuss how the brightness
distribution keeps a record of the large-scale structures formation scenario,
providing a snapshot of the 'melting pot' in the virialization region.


title: Rotational-vibrational coupling in the BPS Skyrme model of baryons

abstract:
  We calculate the rotational-vibrational spectrum in the BPS Skyrme model for
the hedgehog skyrmion with baryon number one. The resulting excitation energies
for the nucleon and delta Roper resonances are slightly above their
experimental values. Together with the fact that in the standard Skyrme model
these excitation energies are significantly lower than the experimental ones,
this provides strong evidence for the conjecture that the inclusion of the BPS
Skyrme model is necessary for a successful quantitative description of physical
properties of baryons and nuclei.


title:
Feedback regulated star formation: II. dual constraints on the SFE and
  the age spread of stars in massive clusters

abstract:
  We show that the termination of the star formation process by winds from
massive stars in protocluster forming clumps imposes dual constraints on the
star formation efficiencies (SFEs) and stellar age spreads ($\Delta \tau_{*}$)
in stellar clusters. We have considered two main classes of clump models. One
class of models in one in which the core formation efficiency (CFE) per unit
time and as a consequence the star formation rate (SFR) is constant in time and
another class of models in which the CFE per unit time, and as a consequence
the SFR, increases with time. Models with an increasing mode of star formation
yield shorter age spreads (a few 0.1 Myrs) and typically higher SFEs than
models in which star formation is uniform in time. We find that the former
models reproduce remarkably well the SFE$-\Delta \tau_{*}$ values of starburst
clusters such as NGC 3603 YC and Westerlund 1, while the latter describe better
the star formation process in lower density environments such as in the Orion
Nebula Cluster. We also show that the SFE and $\Delta \tau_{*}$ of massive
clusters are expected to be higher in low metallicity environments. This could
be tested with future large extragalactic surveys of stellar clusters. We
advocate that placing a stellar cluster on the SFE-$\Delta \tau_{*}$ diagram is
a powerful method to distinguish between different stellar clusters formation
scenarios such as between generic gravitational instability of a gas
cloud/clump or as the result of cloud-cloud collisions. It is also a very
useful tool for testing star formation theories and numerical models versus the
observations.


title: A lithium depletion boundary age of 22 Myr for NGC 1960

abstract:
  We present a deep Cousins RI photometric survey of the open cluster NGC 1960,
complete to R_C \simeq 22, I_C \simeq 21, that is used to select a sample of
very low-mass cluster candidates. Gemini spectroscopy of a subset of these is
used to confirm membership and locate the age-dependent "lithium depletion
boundary" (LDB) --the luminosity at which lithium remains unburned in its
low-mass stars. The LDB implies a cluster age of 22 +/-4 Myr and is quite
insensitive to choice of evolutionary model. NGC 1960 is the youngest cluster
for which a LDB age has been estimated and possesses a well populated upper
main sequence and a rich low-mass pre-main sequence. The LDB age determined
here agrees well with precise age estimates made for the same cluster based on
isochrone fits to its high- and low-mass populations. The concordance between
these three age estimation techniques, that rely on different facets of stellar
astrophysics at very different masses, is an important step towards calibrating
the absolute ages of young open clusters and lends confidence to ages
determined using any one of them.


title: Nonequilibrium self-energy functional theory

abstract:
  The self-energy functional theory (SFT) is generalized to describe the
real-time dynamics of correlated lattice-fermion models far from thermal
equilibrium. This is achieved by means of a reformulation of the original
equilibrium theory in terms of double-time Green's functions on the
Keldysh-Matsubara contour. We construct a functional which is stationary at the
physical (nonequilibrium) self-energy and which yields the grand potential of
the initial thermal state at the physical point. Non-perturbative
approximations can be defined by specifying a reference system that serves to
generate trial self-energies. These self-energies are varied by varying the
reference system's one-particle parameters on the Keldysh-Matsubara contour. In
case of thermal equilibrium, the new approach reduces to the conventional SFT.
However, "unphysical" variations, i.e., variations that are different on the
upper and the lower branch of the Keldysh contour, must be considered to fix
the time-dependence of the optimal physical parameters via the variational
principle. Functional derivatives in the nonequilibrium SFT Euler equation are
carried out analytically to derive conditional equations for the variational
parameters that are accessible to a numerical evaluation via a time-propagation
scheme. Approximations constructed by means of the nonequilibrium SFT are shown
to be inherently causal, internally consistent and to respect macroscopic
conservation laws resulting from gauge symmetries of the Hamiltonian. This
comprises the nonequilibrium dynamical mean-field theory but also
dynamical-impurity and variational-cluster approximations that are specified by
reference systems with a finite number of degrees of freedom. In this way,
non-perturbative and consistent approximations can be set up, the numerical
evaluation of which is accessible to an exact-diagonalization approach.


title: An on-shell approach to factorization

abstract:
  Factorization is possible due to the universal behavior of Yang-Mills
theories in soft and collinear limits. Here, we take a small step towards a
more transparent understanding of these limits by proving a form of
perturbative factorization at tree- level using on-shell spinor helicity
methods. We present a concrete and self-contained expression of factorization
in which matrix elements in QCD are related to products of other matrix
elements in QCD up to leading order in a power-counting parameter determined by
the momenta of certain physical on-shell states. Our approach uses only the
scaling of momenta in soft and collinear limits, avoiding any assignment of
scaling behavior to unphysical (and gauge-dependent) fields. The proof of
factorization exploits many advantages of helicity spinors, such as the freedom
to choose different reference vectors for polarizations in different collinear
sectors. An advantage of this approach is that once factorization is shown to
hold in QCD, the transition to Soft-Collinear Effective Theory is effortless.


title:
Internal bremsstrahlung signatures in light of direct dark matter
  searches

abstract:
  Although proposed long ago, the search for internal bremsstrahlung signatures
has only recently been made possible by the excellent energy resolution of
ground-based and satellite-borne gamma-ray instruments. Here, we investigate
thoroughly the current status of internal bremsstrahlung searches in light of
the results of direct dark matter searches and in the framework of a minimal
mass-degenerate scenario consisting of a Majorana dark matter particle that
couples to a fermion and a scalar via a Yukawa coupling. The upper limits on
the annihilation cross section set by Fermi-LAT and H.E.S.S. extend
uninterrupted from tens of GeV up to tens of TeV and are rather insensitive to
the mass degeneracy in the particle physics model. In contrast, direct searches
are best in the moderate to low mass splitting regime, where XENON100 limits
overshadow Fermi-LAT and H.E.S.S. up to TeV masses if dark matter couples to
one of the light quarks. In our minimal scenario we examine carefully the
prospects for GAMMA-400, CTA and XENON1T, all planned to come online in the
near future, and find that: (a) CTA and XENON1T are fully complementary, with
CTA most sensitive to multi-TeV masses and mass splittings around 10%, and
XENON1T probing best small mass splittings up to TeV masses; and (b) current
constraints from XENON100 already preclude the observation of any spectral
feature with GAMMA-400 in spite of its impressive energy resolution, unless
dark matter does not couple predominantly to light quarks. Finally, we point
out that, unlike for direct searches, the possibility of detecting thermal
relics in upcoming internal bremsstrahlung searches requires, depending on the
concrete scenario, boost factors larger than 5-10.


title: Signatures of Majorana fermions in hybrid normal-superconducting rings

abstract:
  We investigate persistent currents in metallic rings interrupted by a Coulomb
blockaded topological superconducting segment. We show that the presence of
Majorana bound states in the superconductor is reflected in the emergence of an
h/e harmonics in the persistent current, whose sign is determined by the
fermion parity of the superconductor. The Majorana bound states further render
the current finite at zero flux, nevertheless the resulting peculiar symmetry
of the persistent current is compatible with a free energy that is even in
time-reversal symmetry breaking fields. These unique features of the persistent
currents are robust against disorder and provide unambiguous signatures of the
presence of Majorana fermions.