title: How to scale distributed deep learning?

abstract:
  Training time on large datasets for deep neural networks is the principal
workflow bottleneck in a number of important applications of deep learning,
such as object classification and detection in automatic driver assistance
systems (ADAS). To minimize training time, the training of a deep neural
network must be scaled beyond a single machine to as many machines as possible
by distributing the optimization method used for training. While a number of
approaches have been proposed for distributed stochastic gradient descent
(SGD), at the current time synchronous approaches to distributed SGD appear to
be showing the greatest performance at large scale. Synchronous scaling of SGD
suffers from the need to synchronize all processors on each gradient step and
is not resilient in the face of failing or lagging processors. In asynchronous
approaches using parameter servers, training is slowed by contention to the
parameter server. In this paper we compare the convergence of synchronous and
asynchronous SGD for training a modern ResNet network architecture on the
ImageNet classification problem. We also propose an asynchronous method,
gossiping SGD, that aims to retain the positive features of both systems by
replacing the all-reduce collective operation of synchronous training with a
gossip aggregation algorithm. We find, perhaps counterintuitively, that
asynchronous SGD, including both elastic averaging and gossiping, converges
faster at fewer nodes (up to about 32 nodes), whereas synchronous SGD scales
better to more nodes (up to about 100 nodes).


title:
Symmetric and antisymmetric forms of the Pauli master equation (for
  interaction of matter and antimatter quantum states)

abstract:
  When applied to matter and antimatter states, the Pauli master equation (PME)
may have two forms: time-symmetric, which is conventional, and
time-antisymmetric, which is suggested in the present work. The symmetric and
antisymmetric forms correspond to symmetric and antisymmetric extensions of
thermodynamics from matter to antimatter --- this is demonstrated by proving
the corresponding H-theorem. The two forms are based on the thermodynamic
similarity of matter and antimatter and differ only in the directions of
thermodynamic time for matter and antimatter (the same in the time-symmetric
case and the opposite in the time-antisymmetric case). We demonstrate that,
while the symmetric form of PME predicts an equi-balance between matter and
antimatter, the antisymmetric form of PME favours full conversion of antimatter
into matter. At this stage, it is impossible to make an experimentally
justified choice in favour of the symmetric or antisymmetric versions of
thermodynamics since we have no experience of thermodynamic properties of
macroscopic objects made of antimatter, but experiments of this kind may become
possible in the future.


title:
Degree Distribution, Rank-size Distribution, and Leadership Persistence
  in Mediation-Driven Attachment Networks

abstract:
  We investigate the growth of a class of networks in which a new node first
picks a mediator at random and connects with $m$ randomly chosen neighbors of
the mediator at each time step. We show that degree distribution in such a
mediation-driven attachment (MDA) network exhibits power-law $P(k)\sim
k^{-\gamma(m)}$ with a spectrum of exponents depending on $m$. To appreciate
the contrast between MDA and Barab\'{a}si-Albert (BA) networks, we then discuss
their rank-size distribution. To quantify how long a leader, the node with the
maximum degree, persists in its leadership as the network evolves, we
investigate the leadership persistence probability $F(\tau)$ i.e. the
probability that a leader retains its leadership up to time $\tau$. We find
that it exhibits a power-law $F(\tau)\sim \tau^{-\theta(m)}$ with persistence
exponent $\theta(m) \approx 1.51 \ \forall \ m$ in the MDA networks and
$\theta(m) \rightarrow 1.53$ exponentially with $m$ in the BA networks.


title: Ground-state OH maser distributions in the Galactic Centre region

abstract:
  Ground-state OH masers identified in the Southern Parkes Large-Area Survey in
Hydroxyl were observed with the Australia Telescope Compact Array to obtain
positions with high accuracy ($\sim$1\,arcsec). We classified these OH masers
into evolved star OH maser sites, star formation OH maser sites, supernova
remnant OH maser sites, planetary nebula OH maser sites and unknown maser sites
using their accurate positions. Evolved star and star formation OH maser sites
in the Galactic Centre region (between Galactic longitudes of $-5^{\circ}$ to
$+5^{\circ}$ and Galactic latitudes of $-2^{\circ}$ and $+2^{\circ}$) were
studied in detail to understand their distributions.


title:
Energy levels, radiative rates and electron impact excitation rates for
  transitions in Si III

abstract:
  Energy levels and radiative rates (A-values) for four types of transitions
(E1, E2, M1, and M2) are reported for an astrophysically important Mg-like ion
Si~III, whose emission lines have been observed in a variety of plasmas. For
the calculations, well-known and widely-used GRASP code has been adopted, and
results are listed for transitions among the 141 levels of the 3$\ell3\ell'$
and 3$\ell$4$\ell$ configurations. Experimental energies are available for only
the lowest 58 levels but there is no major discrepancy with theoretical
results. Similarly, the A-values and lifetimes show a satisfactory agreement
with other available results, particularly for strong E1 transitions. Collision
strengths are also calculated, with the DARC code, and listed for resonance
transitions over a wide energy range, up to 30~Ryd. No similar results are
available in the literature for comparisons. However, comparisons are made with
the more important parameter, effective collision strength ($\Upsilon$), for
which recent $R$-matrix results are available for a wide range of transitions,
and over a large range of temperatures. To determine $\Upsilon$, resonances
have been resolved in a narrow energy mesh, although these are not observed to
be as important as for other ions. Unfortunately, large discrepancies in
$\Upsilon$ values are noted for about half the transitions. The differences
increase with increasing temperature and worsen as the upper level J increases.
In most cases the earlier results are overestimated, by up to (almost) two
orders of magnitude, and this conclusion is consistent with the one observed
earlier for Be-like ions.


title: Quantifying Chiral Magnetic Effect from Anomalous-Viscous Fluid Dynamics

abstract:
  The Chiral Magnetic Effect (CME) is a macroscopic manifestation of
fundamental chiral anomaly in a many-body system of chiral fermions, and
emerges as anomalous transport current in the fluid dynamics framework.
Experimental observation of CME is of great interest and has been reported in
Dirac and Weyl semimetals. Significant efforts have also been made to look for
CME in heavy ion collisions. Critically needed for such search, is the
theoretical prediction for CME signal. In this paper we report a first
quantitative modeling framework, the Anomalous Viscous Fluid Dynamics (AVFD),
which computes the evolution of fermion currents on top of realistic bulk
evolution in heavy ion collisions and simultaneously accounts for both
anomalous and normal viscous transport effects. The AVFD allows a quantitative
understanding of the generation and evolution of CME-induced charge separation
during hydrodynamic stage as well as its dependence on theoretical ingredients.
With reasonable estimates of key parameters, the AVFD simulations provide the
first phenomenologically successful explanation of the measured signal in
200AGeV AuAu collisions.


title:
PHIBSS: Exploring the Dependence of the CO-H$_2$ Conversion Factor on
  Total Mass Surface Density at ${\it z} < 1.5$

abstract:
  We present an analysis of the relationship between the CO-H$_{2}$ conversion
factor ($\alpha_{\rm CO}$) and total mass surface density ($\Sigma_{\rm tot}$)
in star-forming galaxies at $z < 1.5$. Our sample, which is drawn from the IRAM
Plateau de Bure HIgh-$z$ Blue Sequence Survey (PHIBSS) and the CO Legacy
Database for GASS (COLD GASS), includes 'normal,' massive star-forming galaxies
that dominate the evolution of the cosmic star formation rate (SFR) at this
epoch and probe the $\Sigma_{\rm tot}$ regime where the strongest variation in
$\alpha_{\rm CO}$ is observed. We constrain $\alpha_{\rm CO}$ via existing CO
observations, measurements of the star formation rate, and an assumed molecular
gas depletion time ($t_{\rm dep}$=$M_{\rm gas}$/SFR) --- the latter two of
which establish the total molecular gas mass independent of the observed CO
luminosity. For a broad range of adopted depletion times, we find that
$\alpha_{\rm CO}$ is independent of total mass surface density, with little
deviation from the canonical Milky Way value. This runs contrary to a scenario
in which $\alpha_{\rm CO}$ decreases as surface density increases within the
extended clouds of molecular gas that potentially fuel clumps of star formation
in $z\sim1$ galaxies, similar to those observed in local ULIRGs. Instead, our
results suggest that molecular gas, both at $z\sim0$ and $z\sim1$, is primarily
in the form of self-gravitating molecular clouds. While CO observations suggest
a factor of $\sim3$ reduction in the average molecular gas depletion time
between $z \sim 0$ and $z\sim1$, we find that, for typical galaxies, the
structure of molecular gas and the process of star formation at $z \sim 1$ is
otherwise remarkably similar to that observed in local star-forming systems.


title: Siegel Modular Forms and Black Hole Entropy

abstract:
  We discuss the application of Siegel Modular Forms to Black Hole entropy
counting. The role of the Igusa cusp form $\chi_{10}$ in the D1D5P system is
well-known, and its transformation properties are what allows precision
microstate counting in this case. We apply a similar method to extract the
Fourier coefficients of other Siegel modular and paramodular forms, and we show
that they could serve as candidates for other types of black holes. We
investigate the growth of their coefficients, identifying the dominant
contributions and the leading logarithmic corrections in various regimes. We
also discuss similarities and differences to the behavior of $\chi_{10}$, and
possible physical interpretations of such forms both from a microscopic and
gravitational point of view.


title: Dynamical friction in the primordial neutrino sea

abstract:
  Standard big bang cosmology predicts a cosmic neutrino background at $T_\nu
\simeq 1.95~$K. Given the current neutrino oscillation measurements, we know
most neutrinos move at large, but non-relativistic, velocities. Therefore, dark
matter haloes moving in the sea of primordial neutrinos form a neutrino wake
behind them, which would slow them down, due to the effect of {\it dynamical
friction}. In this paper, we quantify this effect for realistic haloes, in the
context of the halo model of structure formation, and show that it scales as
$m_\nu^4$ $\times$ relative velocity, and monotonically grows with the halo
mass. Galaxy redshift surveys can be sensitive to this effect (at $>3\sigma$
confidence level, depending on survey properties, neutrino mass and hierarchy)
through redshift space distortions (RSD) of distinct galaxy populations.


title: Cores in Dwarf Galaxies from Fermi Repulsion

abstract:
  We show that Fermi repulsion can lead to cored density profiles in dwarf
galaxies for sub-keV fermionic dark matter. We treat the dark matter as a
quasi-degenerate self-gravitating Fermi gas and calculate its density profile
assuming hydrostatic equilibrium. We find that suitable dwarf galaxy cores of
larger than 130 pc can be achieved for fermion dark matter with mass in the
range 70 eV - 400 eV. While in conventional dark matter scenarios, such sub-keV
thermal dark matter would be excluded by free streaming bounds, the constraints
are ameliorated in models with dark matter at lower temperature than
conventional thermal scenarios, such as the Flooded Dark Matter model that we
have previously considered. Modifying the arguments of Tremaine and Gunn we
derive a conservative lower bound on the mass of fermionic dark matter of 70 eV
and a stronger lower bound from Lyman-$\alpha$ clouds of about 470 eV, leading
to slightly smaller cores than have been observed. We comment on this result
and how the tension is relaxed in dark matter scenarios with non-thermal
momentum distributions.


title:
Preparation of Low Entropy Correlated Many-body States via Conformal
  Cooling Quenches

abstract:
  We analyze a method for preparing low-entropy many-body states in isolated
quantum optical systems of atoms, ions and molecules. Our approach is based
upon shifting entropy between different regions of a system by spatially
modulating the magnitude of the effective Hamiltonian. We conduct two case
studies, on a topological spin chain and the spinful fermionic Hubbard model,
focusing on the key question: can a "conformal cooling quench" remove
sufficient entropy within experimentally accessible timescales? Finite
temperature, time-dependent matrix product state calculations reveal that even
moderately sized "bath" regions can remove enough energy and entropy density to
expose coherent low temperature physics. The protocol is particularly natural
in systems with long-range interactions such lattice-trapped polar molecules
and Rydberg dressed atoms where the magnitude of the Hamiltonian scales
directly with the density. To this end, we propose a simple implementation of
conformal cooling quenches in a dilutely-filled optical lattice, where
signatures of quantum magnetism can be observed.


title: 2D CFT Partition Functions at Late Times

abstract:
  We consider the late time behavior of the analytically continued partition
function $Z(\beta + it) Z(\beta - it)$ in holographic $2d$ CFTs. This is a
probe of information loss in such theories and in their holographic duals. We
show that each Virasoro character decays in time, and so information is not
restored at the level of individual characters. We identify a universal
decaying contribution at late times, and conjecture that it describes the
behavior of generic chaotic $2d$ CFTs out to times that are exponentially large
in the central charge. It was recently suggested that at sufficiently late
times one expects a crossover to random matrix behavior. We estimate an upper
bound on the crossover time, which suggests that the decay is followed by a
parametrically long period of late time growth. Finally, we discuss integrable
theories and show how information is restored at late times by a series of
characters. This hints at a possible bulk mechanism, where information is
restored by an infinite sum over non-perturbative saddles.


title: Simplified Models for Dark Matter Face their Consistent Completions

abstract:
  Simplified dark matter models have been recently advocated as a powerful tool
to exploit the complementarity between dark matter direct detection, indirect
detection and LHC experimental probes. Focusing on pseudoscalar mediators
between the dark and visible sectors, we show that the simplified dark matter
model phenomenology departs significantly from that of consistent
${SU(2)_{\mathrm{L}} \times U(1)_{\mathrm{Y}}}$ gauge invariant completions. We
discuss the key physics simplified models fail to capture, and its impact on
LHC searches. Notably, we show that resonant mono-Z searches provide
competitive sensitivities to standard mono-jet analyses at $13$ TeV LHC.


title:
Phase diagram of electronic systems with quadratic Fermi nodes in
  $2<d<4$: $2+\epsilon$ expansion, $4-\epsilon$ expansion, and functional
  renormalization group

abstract:
  Several materials in the regime of strong spin-orbit interaction such as
HgTe, the pyrochlore iridate Pr$_2$Ir$_2$O$_7$, and the half-Heusler compound
LaPtBi, as well as various systems related to these three prototype materials,
are believed to host a quadratic band touching point at the Fermi level.
Recently, it has been proposed that such a three-dimensional gapless state is
unstable to a Mott-insulating ground state at low temperatures when the number
of band touching points $N$ at the Fermi level is smaller than a certain
critical number $N_c$. We further substantiate and quantify this scenario by
various approaches. Using $\epsilon$ expansion near two spatial dimensions, we
show that $N_c = 64/(25 \epsilon^2) + O(1/\epsilon)$ and demonstrate that the
instability for $N < N_c$ is towards a nematic ground state that can be
understood as if the system were under (dynamically generated) uniaxial strain.
We also propose a truncation of the functional renormalization group equations
in the dynamical bosonization scheme which we show to agree to one-loop order
with the results from $\epsilon$ expansion both near two as well as near four
dimensions, and which smoothly interpolates between these two perturbatively
accessible limits for general $2<d<4$. Directly in $d=3$ we therewith find $N_c
= 1.86$, and thus again above the physical $N=1$. All these results are
consistent with the prediction that the interacting ground state of pure,
unstrained HgTe, and possibly also Pr$_2$Ir$_2$O$_7$, is a strong topological
insulator with a dynamically-generated gap -- a topological Mott insulator.


title:
On the Survival of High-Altitude Open Clusters within the Milky Way
  Galaxy Tides

abstract:
  It is a common assumption that high-altitude open clusters live longer
compared with clusters moving close to the Galactic plane. This is because at
high altitudes, open clusters are far from the disruptive effects of in-plane
substructures, such as spiral arms, molecular clouds and the bar. However, an
important aspect to consider in this scenario is that orbits of high-altitude
open clusters will eventually cross the Galactic plane, where the vertical
tidal field of the disk is strong. In this work we simulate the interaction of
open clusters with the tidal field of a detailed Milky Way Galactic model at
different average altitudes and galactocentric radii. We find that the life
expectancy of clusters decreases as the maximum orbital altitude increases and
reaches a minimum at altitudes of approximately 600 pc. Clusters near the
Galactic plane live longer because they do not experience strong vertical tidal
shocks from the Galactic disk; then, for orbital altitudes higher than 600 pc,
clusters start again to live longer due to the decrease in the number of
encounters with the disk. With our study, we find that the compressive nature
of the tides in the arms region and the bar have an important role on the
survival of small clusters by protecting them from disruption: clusters inside
the arms can live up to twice as long as those outside the arms at similar
galactocentric distance.


title:
Gravity Spy: Integrating Advanced LIGO Detector Characterization,
  Machine Learning, and Citizen Science

abstract:
  (abridged for arXiv) With the first direct detection of gravitational waves,
the Advanced Laser Interferometer Gravitational-wave Observatory (LIGO) has
initiated a new field of astronomy by providing an alternate means of sensing
the universe. The extreme sensitivity required to make such detections is
achieved through exquisite isolation of all sensitive components of LIGO from
non-gravitational-wave disturbances. Nonetheless, LIGO is still susceptible to
a variety of instrumental and environmental sources of noise that contaminate
the data. Of particular concern are noise features known as glitches, which are
transient and non-Gaussian in their nature, and occur at a high enough rate so
that accidental coincidence between the two LIGO detectors is non-negligible.
In this paper we describe an innovative project that combines crowdsourcing
with machine learning to aid in the challenging task of categorizing all of the
glitches recorded by the LIGO detectors. Through the Zooniverse platform, we
engage and recruit volunteers from the public to categorize images of glitches
into pre-identified morphological classes and to discover new classes that
appear as the detectors evolve. In addition, machine learning algorithms are
used to categorize images after being trained on human-classified examples of
the morphological classes. Leveraging the strengths of both classification
methods, we create a combined method with the aim of improving the efficiency
and accuracy of each individual classifier. The resulting classification and
characterization should help LIGO scientists to identify causes of glitches and
subsequently eliminate them from the data or the detector entirely, thereby
improving the rate and accuracy of gravitational-wave observations. We
demonstrate these methods using a small subset of data from LIGO's first
observing run.

categories: gr-qc astro-ph.HE astro-ph.IM physics.ins-det


title:
AGN feedback and the origin of the $\alpha$ enhancement in early type
  galaxies - insights from the GAEA model

abstract:
  We take advantage of our recently published model for Galaxy Evolution and
Assembly (GAEA) to study the origin of the observed correlation between
[$\alpha$/Fe] and galaxy stellar mass. In particular, we analyse the role of
radio mode AGN feedback, that recent work has identified as a crucial
ingredient to reproduce observations. In GAEA, this process introduces the
observed trend of star formation histories extending over shorter time-scales
for more massive galaxies, but does not provide a sufficient condition to
reproduce the observed $\alpha$ enhancements of massive galaxies. In the
framework of our model, this is possible only assuming that any residual star
formation is truncated for galaxies more massive than $10^{10.5}\,{\rm
M}_{\odot}$. This results, however, in even shorter star formation time-scales
for the most massive galaxies, that translate in total stellar metallicities
significantly lower than observed. Our results demonstrate that (i) trends of
[$\alpha$/Fe] ratios cannot be simply converted in relative time-scale
indicators, and (ii) AGN feedback cannot explain alone the positive correlation
between [$\alpha$/Fe] and galaxy mass/velocity dispersion. Reproducing
simultaneously the mass-metallicity relation and the $\alpha$ enhancements
observed poses a challenge for hierarchical models, unless more exotic
solutions are adopted such as metal-rich winds or a variable IMF.


title: Sterile Neutrinos and Flavor Ratios in IceCube

abstract:
  The flavor composition of astrophysical neutrinos observed in neutrino
telescopes is a powerful discriminator between different astrophysical neutrino
production mechanisms and can also teach us about the particle physics
properties of neutrinos. In this paper, we investigate how the possible
existence of light sterile neutrinos can affect these flavor ratios. We
consider two scenarios: (i) neutrino production in conventional astrophysical
sources, followed by partial oscillation into sterile states; (ii) neutrinos
from dark matter decay with a primary flavor composition enhanced in tau
neutrinos or sterile neutrinos. Throughout the paper, we constrain the sterile
neutrino mixing parameters from a full global fit to short and long baseline
data. We present our results in the form of flavor triangles and, for scenario
(ii), as exclusion limits on the dark matter mass and lifetime, derived from a
fit to IceCube high energy starting events and through-going muons. We argue
that identifying a possible flux of neutrinos from dark matter decay may
require analyzing the flavor composition as a function of neutrino energy.


title: Dark Cosmic Rays

abstract:
  If dark matter particles have an electric charge, as in models of
millicharged dark matter, such particles should be accelerated in the same
astrophysical accelerators that produce ordinary cosmic rays, and their spectra
should have a predictable rigidity dependence. Depending on the charge, the
resulting "dark cosmic rays" can be detected as muon-like or neutrino-like
events in Super-Kamiokande, IceCube, and other detectors. We present new limits
and propose several new analyses, in particular, for the Super-Kamiokande
experiment, which can probe a previously unexplored portion of the millicharged
dark matter parameter space. Most of our results are fairly general and apply
to a broad class of dark matter models.


title:
The Clouds are breaking: tracing the Magellanic system with Gaia DR1
  Mira variables

abstract:
  We exploit the first data release from the Gaia mission to identify candidate
Mira variables in the outskirts of the Magellanic Clouds. The repeated
observations of sources during the initial phase of the Gaia mission is used to
identify stars that show signs of variability. This variability information,
combined with infrared photometry from 2MASS and WISE, allows us to select a
clean sample of giants in the periphery of the LMC. We find evidence for Miras
surrounding the LMC out to ~20 deg in all directions, apart from the North-West
quadrant. Our sample does not generally follow the gas distribution of the
Magellanic system; Miras are notably absent in the gaseous bridge between the
LMC and SMC, but they are likely related to the stellar RR Lyrae bridge
reported by Belokurov et al. (2016). The stellar stream discovered by Mackey et
al. (2016) to the North of the LMC is almost perfectly delineated by our Mira
variables, and likely extends further East toward the Galactic plane. The
presence of an intermediate-age population in this stream advocates an LMC disc
origin. We also find a significant excess of Miras to the East of the LMC;
these more diffusely distributed stars are likely stripped SMC stars due to
interactions with the LMC. Miras are also identified in regions of the sky away
from the Clouds; we locate stars likely associated with known massive
substructures, and also find potential associations with stripped SMC debris
above the Galactic plane.


title:
The impact of non-thermal electrons on event horizon scale images and
  spectra of Sgr A*

abstract:
  Decomposing an arbitrary electron energy distribution into sums of Maxwellian
and power law components is an efficient method to calculate synchrotron
emission and absorption. We use this method to study the effect of non-thermal
electrons on submm images and spectra of the Galactic center black hole, Sgr
A*. We assume a spatially uniform functional form for the electron distribution
function and use a semi-analytic radiatively inefficient accretion flow and a
2D general relativistic MHD snapshot as example models of the underlying
accretion flow structure. We develop simple analytic models which allow us to
generalize from the numerical examples. A high energy electron component
containing a small fraction (few per cent) of the total internal energy (e.g. a
"power law tail") can produce a diffuse halo of emission, which modifies the
observed image size and structure. A population of hot electrons with a larger
energy fraction (e.g. resulting from a diffusion in electron energy space) can
dominate the emission, so that the observed images and spectra are well
approximated by considering only a single thermal component for a suitable
choice of the electron temperature. We discuss the implications of these
results for estimating accretion flow or black hole parameters from images and
spectra, and for the identification of the black hole "shadow" in future
mm-VLBI data. In particular, the location of the first minimum in visibility
profiles does not necessarily correspond to the shadow size as sometimes
assumed.


title:
Modeling the Radio Foreground for detection of CMB spectral distortions
  from Cosmic Dawn and Epoch of Reionization

abstract:
  Cosmic baryon evolution during the Cosmic Dawn and Reionization results in
redshifted 21-cm spectral distortions in the cosmic microwave background (CMB).
These encode information about the nature and timing of first sources over
redshifts 30-6 and appear at meter wavelengths as a tiny CMB distortion along
with the Galactic and extragalactic radio sky, which is orders of magnitude
brighter. Therefore, detection requires precise methods to model foregrounds.
We present a method of foreground fitting using maximally smooth (MS)
functions. We demonstrate the usefulness of MS functions over traditionally
used polynomials to separate foregrounds from the Epoch of Reionization (EoR)
signal. We also examine the level of spectral complexity in plausible
foregrounds using GMOSS, a physically motivated model of the radio sky, and
find that they are indeed smooth and can be modeled by MS functions to levels
sufficient to discern the vanilla model of the EoR signal. We show that MS
functions are loss resistant and robustly preserve EoR signal strength and
turning points in the residuals. Finally, we demonstrate that in using a
well-calibrated spectral radiometer and modeling foregrounds with MS functions,
the global EoR signal can be detected with a Bayesian approach with 90\%
confidence in 10 minutes' integration.


title: A Quantum Check of AdS/dCFT

abstract:
  We build the framework for performing loop computations in the defect version
of N=4 super Yang-Mills theory which is dual to the probe D5-D3 brane system
with background gauge-field flux. In this dCFT, a codimension-one defect
separates two regions of space-time with different ranks of the gauge group and
three of the scalar fields acquire non-vanishing and space-time-dependent
vacuum expectation values. The latter leads to a highly non-trivial mass mixing
problem between different colour and flavour components, which we solve using
fuzzy-sphere coordinates. Furthermore, the resulting space-time dependence of
the theory's Minkowski space propagators is handled by reformulating these as
propagators in an effective AdS4. Subsequently, we initiate the computation of
quantum corrections. The one-loop correction to the one-point function of any
local gauge-invariant scalar operator is shown to receive contributions from
only two Feynman diagrams. We regulate these diagrams using dimensional
reduction, finding that one of the two diagrams vanishes, and discuss the
procedure for calculating the one-point function of a generic operator from the
SU(2) subsector. Finally, we explicitly evaluate the one-loop correction to the
one-point function of the BPS vacuum state, finding perfect agreement with an
earlier string-theory prediction. This constitutes a highly non-trivial test of
the gauge-gravity duality in a situation where both supersymmetry and conformal
symmetry are partially broken.


title:
Event-Ready Bell Test Using Entangled Atoms Simultaneously Closing
  Detection and Locality Loopholes

abstract:
  An experimental test of Bell's inequality allows ruling out any
local-realistic description of nature by measuring correlations between distant
systems. While such tests are conceptually simple, there are strict
requirements concerning the detection efficiency of the involved measurements,
as well as the enforcement of spacelike separation between the measurement
events. Only very recently could both loopholes be closed simultaneously. Here
we present a statistically significant, event-ready Bell test based on
combining heralded entanglement of atoms separated by $398\,\mathrm{m}$ with
fast and efficient measurements of the atomic spin states closing essential
loopholes. We obtain a violation with $S=2.221\pm0.033$ (compared to the
maximal value of 2 achievable with models based on local hidden variables)
which allows us to refute the hypothesis of local-realism with a significance
level $P<2.57\cdot10^{-9}$.


title:
Looking for possible new physics in $B\to D^{(\ast)}\tau\nu_{\tau}$ in
  light of recent data

abstract:
  We study the decays $B\to D^{(\ast)}\tau\nu_{\tau}$ in light of the available
data from BABAR, Belle and LHCb. We divide our analysis into two parts: in one
part we fit the form-factors in these decays directly from the data without
adding any additional new physics (NP) contributions and compare our fit
results with those available from the decays $B\to D^{(\ast)}\ell\nu_{\ell}$.
We find that the $q^2$-distributions of the form-factors associated with the
pseudo-vector current, obtained from $B\to D^{(\ast)}\tau\nu_{\tau}$ and $B\to
D^{(\ast)}\ell\nu_{\ell}$ respectively, do not agree with each other, whereas
the other form-factors are consistent with each other. In the next part of our
analysis, we look for possible new effective operators of dimension 6 amongst
new vector, scalar, and tensor-type that can best explain the current data in
the decays $B\to D^{(\ast)}\tau\nu_{\tau}$. We use the information-theoretic
approaches, especially of `Second-order Akaike Information Criterion' (AIC$_c$)
in the analysis of empirical data. Normality tests for the distribution of
residuals are done after selecting the best possible scenarios, for
cross-validation. We find that it is the contribution from the operator
involving left or right-handed vector current that passes all the selection
criteria defined for the best-fit scenario and can successfully accommodate all
the available data set.


title: Selection Rule for Enhanced Dark Matter Annihilation

abstract:
  We point out a selection rule for enhancement (suppression) of odd (even)
partial waves of dark matter coannihilation or annihilation using Sommerfeld
effect. Using this, the usually velocity-suppressed p-wave annihilation can
dominate the annihilation signals in the present Universe. The selection
mechanism is a manifestation of the exchange symmetry of identical incoming
particles, and generic for multi-state DM with off-diagonal long-range
interactions. As a consequence, the relic and late-time annihilation rates are
parametrically different and a distinctive phenomenology, with large but
strongly velocity-dependent annihilation rates, is predicted.


title: Dynamics and Observer-Dependence of Holographic Screens

abstract:
  We study the evolution of holographic screens, both generally and in explicit
examples, including cosmology and gravitational collapse. A screen $H$ consists
of a one-parameter sequence of maximal surfaces called leaves. Its causal
structure is nonrelativistic. Each leaf can store all of the quantum
information on a corresponding null slice holographically, at no more than one
bit per Planck area. Therefore, we expect the screen geometry to reflect
certain coarse-grained quantities in the quantum gravity theory.
  In a given spacetime, there are many different screens, which are naturally
associated to different observers. We find that this ambiguity corresponds
precisely to the free choice of a single function on $H$. We also consider the
background-free construction of $H$, where the spacetime is not given. The
evolution equations then constrain aspects of the full spacetime and the
screen's embedding in it.


title:
Incorporating nuclear vibrational energies into the -atom in molecules-
  analysis: An analytical study

abstract:
  The quantum theory of atoms in molecules (QTAIM) is based on the clamped
nucleus paradigm and solely working with the electronic wavefunctions, so does
not include nuclear vibrations in the AIM analysis. On the other hand, the
recently extended version of the QTAIM, called the multi-component QTAIM
(MC-QTAIM), incorporates both electrons and quantum nuclei, i.e. those nuclei
treated as quantum waves instead of clamped point charges, into the AIM
analysis using non-adiabatic wavefunctions. Thus, the MC-QTAIM is the natural
framework to incorporate the role of nuclear vibrations into the AIM analysis.
In this study, within the context of the MC-QTAIM, the formalism of including
nuclear vibrational energy in the atomic basin energy is developed in detail
and its contribution is derived analytically using the recently proposed
non-adiabatic Hartree product nuclear wavefunction. It is demonstrated that
within the context of this wavefunction the quantum nuclei may be conceived
pseudo-adiabatically as quantum oscillators and both isotropic harmonic and
anisotropic anharmonic oscillator models are used to compute the zero-point
nuclear vibrational energy contribution to the basin energies explicitly.
Inspired by the results gained within the context of the MC-QTAIM analysis, a
heuristic approach is proposed within the context of the QTAIM to include
nuclear vibrational energy in the basin energy from the vibrational
wavefunction derived adiabatically. The explicit calculation of the basin
contribution of the zero-point vibrational energy using uncoupled harmonic
oscillator model leads to results consistent with those derived from the
MC-QTAIM.


title:
Environmental impacts on dust temperature of star-forming galaxies in
  the local Universe

abstract:
  We present infrared views of the environmental effects on the dust properties
in star-forming (SF) galaxies at z ~ 0, using the AKARI Far-Infrared Surveyor
(FIS) all-sky map and the large spectroscopic galaxy sample from Sloan Digital
Sky Survey (SDSS) Data Release 7 (DR7). We restrict the sample to those within
the redshift range of 0.05 < z < 0.07 and the stellar mass range of 9.2 <
log_10 (M_star/M_solar). We select SF galaxies based on their H_alpha
equivalent width (EW_Ha> 4 A) and emission line flux ratios. We perform
far-infrared (FIR) stacking analyses by splitting the SDSS SF galaxy sample
according to their stellar mass, specific SFR (SSFR_SDSS), and environment. We
derive total infrared luminosity (LIR) for each subsample using the average
flux densities at WIDE-S (90 micron) and WIDE-L (140 micron) bands, and then
compute IR-based SFR (SFR_IR) from L_IR. We find a mild decrease of IR- based
SSFR (SSFR_IR) amongst SF galaxies with increasing local density (~0.1-dex
level at maximum), which suggests that environmental effects do not instantly
shut down the SF activity in galaxies. We also derive average dust temperature
(T_dust) using the flux densities at 90 micron and 140 micron bands. We confirm
a strong positive correlation between T_dust and SSFR_IR, consistent with
recent studies. The most important finding of this study is that we find a
marginal trend that T_dust increases with increasing environmental galaxy
density. Although the environmental trend is much milder than the SSFR-T_dust
correlation, our results suggest that the environmental density may affect the
dust temperature in SF galaxies, and that the physical mechanism which is
responsible for this phenomenon is not necessarily specific to cluster
environments because the environmental dependence of T_dust holds down to
relatively low-density environments.


title:
Photophoretic Levitation and Trapping of Dust in the Inner Regions of
  Protoplanetary Disks

abstract:
  In protoplanetary disks, the differential gravity-driven settling of dust
grains with respect to gas and with respect to grains of varying sizes
determines the observability of grains, and sets the conditions for grain
growth and eventually planet formation. In this work we explore the effect of
photophoresis on the settling of large dust grains in the inner regions of
actively accreting protoplanetary disks. Photophoretic forces on dust grains
result from the collision of gas molecules with differentially heated grains.
We undertake one dimensional dust settling calculations to determine the
equilibrium vertical distribution of dust grains in each column of the disk. In
the process we introduce a new treatment of the photophoresis force which is
consistent at all optical depths with the representation of the radiative
intensity field in a two-stream radiative transfer approximation. The
levitation of large dust grains creates a photophoretic dust trap several scale
heights above the mid-plane in the inner regions of the disk where the
dissipation of accretion energy is significant. We find that differential
settling of dust grains is radically altered in these regions of the disk, with
large dust grains trapped in a layer below the stellar irradiation surface in
where the dust to gas mass ratio can be enhanced by a factor of a hundred for
the relevant particles. The photophoretic trapping effect has a strong
dependence on particle size and porosity.


title: Connected chord diagrams and bridgeless maps

abstract:
  We present a surprisingly new connection between two well-studied
combinatorial classes: rooted connected chord diagrams on one hand, and rooted
bridgeless combinatorial maps on the other hand. We describe a bijection
between these two classes, which naturally extends to indecomposable diagrams
and general rooted maps. As an application, this bijection provides a
simplifying framework for some technical quantum field theory work realized by
some of the authors. Most notably, an important but technical parameter
naturally translates to vertices at the level of maps. We also give a
combinatorial proof to a formula which previously resulted from a technical
recurrence, and with similar ideas we prove a conjecture of Hihn.
Independently, we revisit an equation due to Arqu\`es and B\'eraud for the
generating function counting rooted maps with respect to edges and vertices,
giving a new bijective interpretation of this equation directly on
indecomposable chord diagrams, which moreover can be specialized to connected
diagrams and refined to incorporate the number of crossings. Finally, we
explain how these results have a simple application to the combinatorics of
lambda calculus, verifying the conjecture that a certain natural family of
lambda terms is equinumerous with bridgeless maps.


title: Global Embedding of Fibre Inflation Models

abstract:
  We present concrete embeddings of fibre inflation models in globally
consistent type IIB Calabi-Yau orientifolds with closed string moduli
stabilisation. After performing a systematic search through the existing list
of toric Calabi-Yau manifolds, we find several examples that reproduce the
minimal setup to embed fibre inflation models. This involves Calabi-Yau
manifolds with $h^{1,1}= 3$ which are K3 fibrations over a $\mathbb{P}^1$ base
with an additional shrinkable rigid divisor. We then provide different
consistent choices of the underlying brane set-up which generate a
non-perturbative superpotential suitable for moduli stabilisation and string
loop corrections with the correct form to drive inflation. For each Calabi-Yau
orientifold setting, we also compute the effect of higher derivative
contributions and study their influence on the inflationary dynamics.


title: On the Optimal Policies for Visibility-Based Target Tracking

abstract:
  In this paper, we investigate a pursuit-evasion game in which a mobile
observer tries to track a target in an environment containing obstacles. We
formulate the game as an optimal control problem with state inequality
constraint in a simple environment. We show that for some initial conditions,
there are two different regimes in the optimal strategy of the pursuer
depending on whether the state-constraint is activated. We derive the equations
that characterize the switching time between the two regimes. The pursuer's
optimal tracking strategy in a simple environment is further extended to a
general environment with multiple polygonal obstacles. We propose techniques to
construct a "pursuit field" based on the optimal solutions to guide the motion
of the observer in a general environment.


title:
Clouds, Streams and Bridges. Redrawing the blueprint of the Magellanic
  System with Gaia DR1

abstract:
  We present the discovery of stellar tidal tails around the Large and the
Small Magellanic Clouds in the Gaia DR1 data. In between the Clouds, their
tidal arms are stretched towards each other to form an almost continuous
stellar bridge. Our analysis relies on the exquisite quality of the Gaia's
photometric catalogue to build detailed star-count maps of the Clouds. We
demonstrate that the Gaia DR1 data can be used to detect variable stars across
the whole sky, and in particular, RR Lyrae stars in and around the LMC and the
SMC. Additionally, we use a combination of Gaia and Gale to follow the
distribution of Young Main Sequence stars in the Magellanic System. Viewed by
Gaia, the Clouds show unmistakable signs of interaction. Around the LMC, clumps
of RR Lyrae are observable as far as ~20 degrees, in agreement with the most
recent map of Mira-like stars reported in Deason et al (2016). The SMC's outer
stellar density contours show a characteristic S-shape, symptomatic of the
on-set of tidal stripping. Beyond several degrees from the center of the dwarf,
the Gaia RR Lyrae stars trace the Cloud's trailing arm, extending towards the
LMC. This stellar tidal tail mapped with RR Lyrae is not aligned with the
gaseous Magellanic Bridge, and is shifted by some ~5 degrees from the Young
Main Sequence bridge. We use the offset between the bridges to put constraints
on the density of the hot gaseous corona of the Milky Way.


title: Discovery of a supercluster in the ZOA in Vela

abstract:
  We report the discovery of a potentially major supercluster that extends
across the Galactic Plane in the constellation of Vela, at a mean recessional
velocity of ~18,000 km/s. Recent multi-object spectroscopic observations of
this Vela Supercluster (VSCL), using AAOmega+2dF and the Southern African Large
Telescope, confirm an extended galaxy overdensity in the Zone of Avoidance
(ZOA) located where residual bulk flows predict a considerable mass excess. We
present a preliminary analysis of ~4,500 new spectroscopic galaxy redshifts
obtained in the ZOA centred on the Vela region (l=272.5+-20 deg, b=0+-10 deg).
The presently sparsely-sampled dataset traces an overdensity that covers 25 deg
in Galactic longitude on either side of the Plane, suggesting an extent of 25
deg x 20 deg, corresponding to ~115 x 90 $h_{70}$ Mpc at the supercluster
redshift. In redshift space, the overdensity appears to consist of two merging
wall-like structures, interspersed with clusters and groups. Both the velocity
histogram and the morphology of the multi-branching wall structure are
consistent with a supercluster classification. $K_s^o$ galaxy counts show an
enhancement of ~1.2 over the survey area for galaxies brighter than $M_K^*$ at
the VSCL distance, and a galaxy overdensity of $\delta=0.50\rm{-}0.77$ within a
photometric redshift shell around the VSCL, when compared to various Two-Micron
All-Sky Survey samples. Taking account of selection effects, the VSCL is
estimated to contribute $v_\rm{LG} \gtrsim 50$ km/s to the motion of the Local
Group.


title: Local effects of the quantum vacuum in Lorentz-violating electrodynamics

abstract:
  The Casimir effect is one of the most remarkable consequences of the non-zero
vacuum energy predicted by quantum field theory. In this paper we use a local
approach to study the Lorentz violation effects of the minimal standard model
extension on the Casimir force between two parallel conducting plates in the
vacuum. Using a perturbative method similar to that used for obtaining the Born
series for the scattering amplitudes in quantum mechanics, we compute, at
leading order in the Lorentz-violating coefficients, the relevant Green's
function which satisfies given boundary conditions. The standard
point-splitting technique allow us to express the vacuum expectation value of
the stress-energy tensor in terms of the Green's function. We discuss its
structure in the region between the plates. We compute the renormalized vacuum
stress, which is obtained as the difference between the vacuum stress in the
presence of the plates and that of the vacuum. The Casimir force is evaluated
in an analytical fashion by two methods: by differentiating the renormalized
global energy density and by computing the normal-normal component of the
renormalized vacuum stress. We compute the local Casimir energy, which is found
to diverge as approaching the plates, and we demonstrate that it does not
contribute to the observable force.


title: The Asymmetric CFT Landscape in D=4,6,8 with Extended Supersymmetry

abstract:
  We study asymmetric simple-current extensions of Gepner models in dimensions
$D=4,6,8$ with at least eight supercharges in the right-moving sector. The
models obtained in an extensive stochastic computer search belong to a small
number of different classes. These classes can be categorized as dimensional
reductions, asymmetric orbifolds with $(-1)^{F_L}$, extra gauge enhancement and
as coming from the super Higgs-effect. Models in the latter class are
particularly interesting, as they may correspond to non-geometric flux
compactifications.


title:
The Gravitational Field Equations of a Twisted Skyrmion String:
  Numerical Solution

abstract:
  We study nonlinear sigma model, especially Skyrme model with twist: twisted
Skyrmion string where twist term, $mkz$, is indicated in vortex solution. To
add gravity, we replace $\eta^{\mu\nu}$ in Lagrangian system with a space-time
metric tensor, $g^{\mu\nu}$, which in view of the time-independence and
cylindrical symmetry of the assumed vortex solution is taken to be a function
of $r$ alone. We use ode45 for numerical calculation, i.e. a tool box in Matlab
to solve coupled Einstein field equations which have ordinary differential
equations (ODE) form.


title:
Two Sample Order Free Trend Inference with an Application in Plant
  Physiology

abstract:
  This work is motivated by a biological experiment with a split-plot design,
for the purpose of comparison of the changing patterns in seed weight from two
treatment groups as subgroups in each of the two groups subject to increasing
levels of stress. We formalize the question into a nonparametric two sample
comparison problem for changes among the sub samples, which was analyzed using
U-statistics. Zero inflated value were also considered in the construction of
the U-statistics. The U-statistics were then used in a Chi-square type test
statistics framework for hypothesis testing. Bootstrapped p-values were
obtained through simulated samples. It was proven that the distribution of the
simulated sample can be independent provided the observed samples have certain
summary statistics. Simulation results suggest that the test is consistent.


title: Operator algebras in rigid C*-tensor categories

abstract:
  In this article, we define operator algebras internal to a rigid C*-tensor
category $\mathcal{C}$. A C*/W*-algebra object in $\mathcal{C}$ is an algebra
object $\mathbf{A}$ in $\operatorname{ind}$-$\mathcal{C}$ whose category of
free modules ${\sf FreeMod}_{\mathcal{C}}(\mathbf{A})$ is a
$\mathcal{C}$-module C*/W*-category respectively. When $\mathcal{C}={\sf
Hilb_{f.d.}}$, the category of finite dimensional Hilbert spaces, we recover
the usual notions of operator algebras.
  We generalize basic representation theoretic results, such as the
Gelfand-Naimark and von Neumann bicommutant theorems, along with the GNS
construction. We define the notion of completely positive maps between
C*-algebra objects in $\mathcal{C}$ and prove the analog of the Stinespring
dilation theorem.
  As an application, we discuss approximation and rigidity properties,
including amenability, the Haagerup property, and property (T) for a connected
W*-algebra $\mathbf{M}$ in $\mathcal{C}$. Our definitions simultaneously unify
the definitions of analytic properties for discrete quantum groups and rigid
C*-tensor categories.


title: Hidden fluctuations close to a quantum bicritical point

abstract:
  In this paper we describe physical properties arising in the vicinity of two
coupled quantum phase transitions. We consider a phenomenological model based
on two scalar order parameter fields locally coupled biquadratically and having
a common quantum critical point as a function of a quantum tuning parameter
such as pressure or magnetic field. A self-consistent treatment suggests that
the uniform static susceptibilities of the two order parameter fields may have
the same qualitative form at low temperature even where the forms differ
sharply in the absence of the biquadratic coupling. The possible limitations of
the self-consistent analysis leading to this prediction are considered.


title:
Clumpy dust clouds and extended atmosphere of the AGB star W Hya
  revealed with VLT/SPHERE-ZIMPOL and VLTI/AMBER II. Time variations between
  pre-maximum and minimum light

abstract:
  Our recent visible polarimetric images of the well-studied AGB star W Hya
taken at pre-maximum light (phase 0.92) with VLT/SPHERE-ZIMPOL have revealed
clumpy dust clouds close to the star at ~2 Rstar. We present second-epoch
SPHERE-ZIMPOL observations of W Hya at minimum light (phase 0.54) in the
continuum (645, 748, and 820 nm), in the Halpha line (656.3 nm), and in the TiO
band (717 nm) as well as high-spectral resolution long-baseline interferometric
observations in 2.3 micron CO lines with the AMBER instrument at the Very Large
Telescope Interferometer (VLTI). The high-spatial resolution polarimetric
images have allowed us to detect clear time variations in the clumpy dust
clouds as close as 34--50~mas (1.4--2.0 Rstar) to the star. We detected the
formation of a new dust cloud and the disappearance of one of the dust clouds
detected at the first epoch. The Halpha and TiO emission extends to ~150 mas
(~6 Rstar), and the Halpha images reveal time variations. The degree of linear
polarization is higher at minimum light (13--18%) than that at pre-maximum
light. The power-law-type limb-darkened disk fit to the AMBER data in the
continuum results in a limb-darkened disk diameter of 49.1+/-1.5 mas and a
limb-darkening parameter of 1.16+/-0.49, indicating that the atmosphere is more
extended with weaker limb-darkening compared to pre-maximum light. Our Monte
Carlo radiative transfer modeling suggests the predominance of small (0.1
micron) grains of Al2O3, Mg2SiO4, and MgSiO3 at minimum light, in marked
contrast to the predominance of large (0.5 micron) grains at pre-maximum light.
The variability phase dependence of the grain size implies that small grains
might just have started to form at minimum light in the wake of a shock, while
the pre-maximum light phase might have corresponded to the phase of efficient
grain growth.


title: On coarse Lipschitz embeddability into $c_0(\kappa)$

abstract:
  In 1994, Jan Pelant proved that a metric property related to the notion of
paracompactness called the uniform Stone property characterizes a metric
space's uniform embeddability into $c_0(\kappa)$ for some cardinality $\kappa$.
In this paper it is shown that coarse Lipschitz embeddability of a metric space
into $c_0(\kappa)$ can be characterized in a similar manner. It is also shown
that coarse, uniform, and bi-Lipschitz embeddability into $c_0(\kappa)$ are
equivalent notions for normed linear spaces.


title: The universal $n$-pointed surface bundle only has $n$ sections

abstract:
  The classifying space BDiff$(S_{g,n})$ of the orientation-preserving
diffeomorphism group of the surface $S_{g,n}$ of genus $g>1$ with $n$ ordered
marked points has a universal bundle \[ S_g \to
\text{UDiff}(S_{g,n})\xrightarrow{\pi}\text{BDiff}(S_{g,n}). \] The fixed $n$
points provide $n$ sections $s_i$ of $\pi$. In this paper we prove a conjecture
of R. Hain that any section of $\pi$ is homotopic to some $s_i$. Let
$\text{PConf}_n(S_g)$ be the ordered $n$-tuples of distinct points on $S_g$. As
part of the proof, we prove a result of independent interest: any surjective
homomorphism $\pi_1(\text{PConf}_n(S_g))\to \pi_1(S_g)$ is equal to one of the
forgetful maps $\{p_i:\pi_1(\text{PConf}_n(S_g))\to \pi_1(S_g)\}$, possibly
post-composed with an automorphism of $\pi_1(S_g)$. Using similar arguments, we
then show that the universal surface bundle that fixes $n$ points as a set does
not have any section.


title: Fighting Fish: enumerative properties

abstract:
  Fighting fish were very recently introduced by the authors as combinatorial
structures made of square tiles that form two dimensional branching surfaces. A
main feature of these fighting fish is that the area of uniform random fish of
size $n$ scales like $n^{5/4}$ as opposed to the typical $n^{3/2}$ area
behavior of the staircase or direct convex polyominoes that they generalize. In
this extended abstract we concentrate on enumerative properties of fighting
fish: in particular we provide a new decomposition and we show that the number
of fighting fish with $i$ left lower free edges and $j$ right lower free edges
is equal to
  \begin{equation*}
  \frac{(2i+j-2)!(2j+i-2)!}{i!j!(2i-1)!(2j-1)!}.
  \end{equation*} These numbers are known to count rooted planar non-separable
maps with $i+1$ vertices and $j+1$ faces, or two-stack-sortable permutations
with respect to ascending and descending runs, or left ternary trees with
respect to vertices with even and odd abscissa. However we have been unable
until now to provide any explicit bijection between our fish and such
structures. Instead we provide new refined generating series for left ternary
trees to prove further equidistribution results.


title:
A search for spectral hysteresis and energy-dependent time lags from
  X-ray and TeV gamma-ray observations of Mrk 421

abstract:
  Blazars are variable emitters across all wavelengths over a wide range of
timescales, from months down to minutes. It is therefore essential to observe
blazars simultaneously at different wavelengths, especially in the X-ray and
gamma-ray bands, where the broadband spectral energy distributions usually
peak.
  In this work, we report on three "target-of-opportunity" (ToO) observations
of Mrk 421, one of the brightest TeV blazars, triggered by a strong flaring
event at TeV energies in 2014. These observations feature long, continuous, and
simultaneous exposures with XMM-Newton (covering X-ray and optical/ultraviolet
bands) and VERITAS (covering TeV gamma-ray band), along with contemporaneous
observations from other gamma-ray facilities (MAGIC and Fermi-LAT) and a number
of radio and optical facilities. Although neither rapid flares nor significant
X-ray/TeV correlation are detected, these observations reveal subtle changes in
the X-ray spectrum of the source over the course of a few days. We search the
simultaneous X-ray and TeV data for spectral hysteresis patterns and time
delays, which could provide insight into the emission mechanisms and the source
properties (e.g. the radius of the emitting region, the strength of the
magnetic field, and related timescales). The observed broadband spectra are
consistent with a one-zone synchrotron self-Compton model. We find that the
power spectral density distribution at $\gtrsim 4\times 10^{-4}$ Hz from the
X-ray data can be described by a power-law model with an index value between
1.2 and 1.8, and do not find evidence for a steepening of the power spectral
index (often associated with a characteristic length scale) compared to the
previously reported values at lower frequencies.


title:
Light equation in eclipsing binary CV Boo: third body candidate in
  elliptical orbit

abstract:
  A short period eclipsing binary star CV Boo is tested for the possible
existence of additional bodies in the system with a help of the light equation
method. We use data on the moments of minima from the literature as well as
from our observations during 2014 May--July. A variation of the CV Boo's
orbital period is found with a period of $\approx 75$ d. This variation can be
explained by the influence of a third star with a mass of $\approx
0.4M_{\odot}$ in an eccentric orbit with $e\approx 0.9$. A possibility that the
orbital period changes on long time scales is discussed. The suggested tertiary
companion is near the chaotic zone around the central binary, so CV Boo
represents an interesting example to test its dynamical evolution. A list of 14
minima moments of the binary obtained from our observations is presented.


title: Marginal and Conditional Second Laws of Thermodynamics

abstract:
  We consider the entropy production of a strongly coupled bipartite system.
The total entropy production can be partitioned into various components, which
we use to define local versions of the Second Law that are valid without the
usual idealization of weak coupling. The key insight is that causal
intervention offers a way to identify those parts of the entropy production
that result from feedback between the sub-systems. From this the central
relations describing the thermodynamics of strongly coupled systems follow in a
few lines.


title: Combined Error Estimates for Local Fluctuations of SPDEs

abstract:
  In this work, we study the numerical approximation of local fluctuations of
certain classes of parabolic stochastic partial differential equations (SPDEs).
Our focus is on effects for small spatially-correlated noise on a time scale
before large deviation effects have occurred. In particular, we are interested
in the local directions of the noise described by a covariance operator. We
introduce a new strategy and prove a Combined ERror EStimate (CERES) for the
five main errors: the spatial discretization error, the local linearization
error, the noise truncation error, the local relaxation error to steady state,
and the approximation error via an iterative low-rank matrix algorithm. In
summary, we obtain one CERES describing, apart from modelling of the original
equations and standard round-off, all sources of error for a local fluctuation
analysis of an SPDE in one estimate. To prove our results, we rely on a
combination of methods from optimal Galerkin approximation of SPDEs, covariance
moment estimates, analytical techniques for Lyapunov equations, iterative
numerical schemes for low-rank solution of Lyapunov equations, and working with
related spectral norms for different classes of operators.


abstract:
  In this paper, we generalize Young's inequality for locally compact quantum
groups and obtain some results for extremal pairs of Young's inequality and
extremal functions of Hausdorff-Young inequality.


title:
Euclidean relativistic quantum mechanics - scattering asymptotic
  conditions

abstract:
  We discuss the formulation of the scattering asymptotic condition in a
relativistic quantum theory formulated in terms of reflection positive
Euclidean Green functions.


title: Experiments on thermoelectric properties of quantum dots

abstract:
  Quantum dots (QDs) are good model systems for fundamental studies of
mesoscopic transport phenomena using thermoelectric effects because of their
small size, electrostatically tunable properties and thermoelectric response
characteristics that are very sensitive to small thermal biases. Here we
provide a review of experimental studies on thermoelectric properties of single
QDs realized in two-dimensional electron gases, single-walled carbon nanotubes
and semiconductor nanowires. A key requirement for such experiments is methods
for nanoscale thermal biasing. We briefly review the main techniques used in
the field, namely, heating of the QD contacts, side heating and top heating,
and touch upon their relative advantages. The thermoelectric response of a QD
as a function of gate potential has a characteristic oscillatory behavior with
the same period as is observed for conductance peaks. Much of the existing
literature focuses on the agreement between experiments and theory,
particularly for amplitude and line-shape of the thermovoltage $V_{th}$. A
general observation is that the widely used single-electron tunneling
approximation for QDs has limited success in reproducing measured $V_{th}$.
Landauer-type calculations are often found to describe measurement results
better despite the large electron-electron interactions in QDs. More recently,
nonlinear thermoelectric effects have moved into the focus of attention and we
offer a brief overview of experiments done so far. We conclude by discussing
open questions and avenues for future work, including the role of asymmetries
in tunnel- and capacitive couplings in thermoelectric behavior of QDs.


title: Hypertemporal Imaging of NYC Grid Dynamics

abstract:
  Hypertemporal visible imaging of an urban lightscape can reveal the phase of
the electrical grid granular to individual housing units. In contrast to
in-situ monitoring or metering, this method offers broad, persistent,
real-time, and non-permissive coverage through a single camera sited at an
urban vantage point. Rapid changes in the phase of individual housing units
signal changes in load (e.g., appliances turning on and off), while slower
building- or neighborhood-level changes can indicate the health of distribution
transformers. We demonstrate the concept by observing the 120 Hz flicker of
lights across a NYC skyline. A liquid crystal shutter driven at 119.75 Hz
down-converts the flicker to 0.25 Hz, which is imaged at a 4 Hz cadence by an
inexpensive CCD camera; the grid phase of each source is determined by analysis
of its sinusoidal light curve over an imaging "burst" of some 25 seconds.
Analysis of bursts taken at ~15 minute cadence over several hours demonstrates
both the stability and variation of phases of halogen, incandescent, and some
fluorescent lights. Correlation of such results with ground-truth data will
validate a method that could be applied to better monitor electricity
consumption and distribution in both developed and developing cities.


title:
EMDUnifrac: Exact Linear Time Computation of the Unifrac Metric and
  Identification of Differentially Abundant Organisms

abstract:
  Both the weighted and unweighted Unifrac distances have been very
successfully employed to assess if two communities differ, but do not give any
information about how two communities differ. We take advantage of recent
observations that the Unifrac metric is equivalent to the so-called earth
mover's distance (also known as the Kantorovich-Rubinstein metric) to develop
an algorithm that not only computes the Unifrac distance in linear time and
space, but also simultaneously finds which operational taxonomic units are
responsible for the observed differences between samples. This allows the
algorithm, called EMDUnifrac, to determine why given samples are different, not
just if they are different, and with no added computational burden. EMDUnifrac
can be utilized on any distribution on a tree, and so is particularly suitable
to analyzing both operational taxonomic units derived from amplicon sequencing,
as well as community profiles resulting from classifying whole genome shotgun
metagenomes. The EMDUnifrac source code (written in python) is freely available
at: https://github.com/dkoslicki/EMDUnifrac.


title: Mitigating the Impact of the DESI Fiber Assignment on Galaxy Clustering

abstract:
  We present a simple strategy to mitigate the impact of an incomplete
spectroscopic redshift galaxy sample as a result of fiber assignment and survey
tiling. The method has been designed for the Dark Energy Spectroscopic
Instrument (DESI) galaxy survey but may have applications beyond this. We
propose a modification to the usual correlation function that nulls the almost
purely angular modes affected by survey incompleteness due to fiber assignment.
Predictions of this modified statistic can be calculated given a model of the
two point correlation function. The new statistic can be computed with a slight
modification to the data catalogues input to the standard correlation function
code and does not incur any additional computational time. Finally we show that
the spherically averaged baryon acoustic oscillation signal is not biased by
the new statistic.


title:
When Saliency Meets Sentiment: Understanding How Image Content Invokes
  Emotion and Sentiment

abstract:
  Sentiment analysis is crucial for extracting social signals from social media
content. Due to the prevalence of images in social media, image sentiment
analysis is receiving increasing attention in recent years. However, most
existing systems are black-boxes that do not provide insight on how image
content invokes sentiment and emotion in the viewers. Psychological studies
have confirmed that salient objects in an image often invoke emotions. In this
work, we investigate more fine-grained and more comprehensive interaction
between visual saliency and visual sentiment. In particular, we partition
images in several primary scene-type dimensions, including: open-closed,
natural-manmade, indoor-outdoor, and face-noface. Using state of the art
saliency detection algorithm and sentiment classification algorithm, we examine
how the sentiment of the salient region(s) in an image relates to the overall
sentiment of the image. The experiments on a representative image emotion
dataset have shown interesting correlation between saliency and sentiment in
different scene types and in turn shed light on the mechanism of visual
sentiment evocation.


title:
The Fast Linear Accelerator Modeling Engine for FRIB Online Model
  Service

abstract:
  Commissioning of a large accelerator facility like FRIB needs support from an
online beam dynamics model. Considering the new physics challenges of FRIB such
as modeling of non-axisymmetric superconducting RF cavities and multi-charge
state acceleration, there is no readily available online beam tuning code. The
design code of FRIB super-conducting linac, IMPACT-Z, is not suitable for
online tuning because of its code design and running speed. Therefore, the Fast
Linear Accelerator Modeling Engine (FLAME), specifically designed to fulfill
FRIB's online modeling challenges, is proposed. The physics model of FLAME,
especially its novel way of modeling non-axisymmetric superconducting RF
cavities using a multipole expansion based thin-lens kick model, is discussed
in detail, and the benchmark results against FRIB design code is presented,
after which the software design strategy of FLAME and its execution speed is
presented.


title: Weak Signal Identification and Inference in Penalized Model Selection

abstract:
  Weak signal identification and inference are very important in the area of
penalized model selection, yet they are under-developed and not well-studied.
Existing inference procedures for penalized estimators are mainly focused on
strong signals. In this paper, we propose an identification procedure for weak
signals in finite samples, and pro- vide a transition phase in-between noise
and strong signal strengths. We also introduce a new two-step inferential
method to construct better confidence intervals for the identified weak
signals. Our theory development assumes that variables are orthogonally
designed. Both theory and numerical studies indicate that the proposed method
leads to better confidence coverage for weak signals, compared with those using
asymptotic inference. In addition, the proposed method out- performs the
perturbation and bootstrap resampling approaches. We illustrate our method for
HIV antiretroviral drug susceptibility data to identify genetic mutations
associated with HIV drug resistance.


title:
Day of the week effect in paper submission/acceptance/rejection to/in/by
  peer review journals. II. An ARCH econometric-like modeling

abstract:
  This paper aims at providing a statistical model for the preferred behavior
of authors submitting a paper to a scientific journal. The electronic
submission of (about 600) papers to the Journal of the Serbian Chemical Society
has been recorded for every day from Jan. 01, 2013 till Dec. 31, 2014, together
with the acceptance or rejection paper fate. Seasonal effects and editor roles
(through desk rejection and subfield editors) are examined. An ARCH-like
econometric model is derived stressing the main determinants of the favorite
day-of-week process.


title: Capturing the 3D Motion of an Infalling Galaxy via Fluid Dynamics

abstract:
  The Fornax Cluster is the nearest galaxy cluster in the southern sky. NGC
1404 is a bright elliptical galaxy falling through the intracluster medium of
the Fornax Cluster. The sharp leading edge of NGC 1404 forms a classical "cold
front" that separates 0.6 keV dense interstellar medium and 1.5 keV diffuse
intracluster medium. We measure the angular pressure variation along the cold
front using a very deep (670\,ksec) {\sl Chandra} X-ray observation. We are
taking the classical approach -- using stagnation pressure to determine a
substructure's speed -- to the next level by not only deriving a general speed
but also directionality which yields the complete velocity field as well as the
distance of the substructure directly from the pressure distribution. We find a
hydrodynamic model consistent with the pressure jump along NGC 1404's
atmosphere measured in multiple directions. The best-fit model gives an
inclination of 33$^{\circ}$ and a Mach number of 1.3 for the infall of NGC
1404, in agreement with complementary measurements of the motion of NGC 1404.
Our study demonstrates the successful treatment of a highly ionized ICM as
ideal fluid flow, in support of the hypothesis that magnetic pressure is not
dynamically important over most of the virial region of galaxy clusters.


title:
Experimental realization and characterization of an electronic Lieb
  lattice

abstract:
  Geometry, whether on the atomic or nanoscale, is a key factor for the
electronic band structure of materials. Some specific geometries give rise to
novel and potentially useful electronic bands. For example, a honeycomb lattice
leads to Dirac-type bands where the charge carriers behave as massless
particles. Theoretical predictions are triggering the exploration of novel 2D
geometries, such as graphynes, Kagom\'{e} and the Lieb lattice. The latter is
the 2D analogue of the 3D lattice exhibited by perovskites; it is a
square-depleted lattice, which is characterised by a band structure featuring
Dirac cones intersected by a topological flat band. Whereas photonic and
cold-atom Lieb lattices have been demonstrated, an electronic equivalent in 2D
is difficult to realize in an existing material. Here, we report an electronic
Lieb lattice formed by the surface state electrons of Cu(111) confined by an
array of CO molecules positioned with a scanning tunneling microscope (STM).
Using scanning tunneling microscopy, spectroscopy and wave-function mapping, we
confirm the predicted characteristic electronic structure of the Lieb lattice.
The experimental findings are corroborated by muffin-tin and tight-binding
calculations. At higher energy, second-order electronic patterns are observed,
which are equivalent to a super-Lieb lattice.


title: Link Prediction using Embedded Knowledge Graphs

abstract:
  Since large knowledge bases are typically incomplete, missing facts need to
be inferred from observed facts in a task called knowledge base completion. The
most successful approaches to this task have typically explored explicit paths
through sequences of triples. These approaches have usually resorted to
human-designed sampling procedures, since large knowledge graphs produce
prohibitively large numbers of possible paths, most of which are uninformative.
As an alternative approach, we propose performing a single, short sequence of
interactive lookup operations on an embedded knowledge graph which has been
trained through end-to-end backpropagation to be an optimized and compressed
version of the initial knowledge base. Our proposed model, called Embedded
Knowledge Graph Network (EKGN), achieves new state-of-the-art results on
popular knowledge base completion benchmarks.


title: Dark Modes of Quantum Linear Systems

abstract:
  In this paper, we develop a direct method for the characterization of dark
modes. The results can be used to construct a transformation that separates
dark and bright modes, through the decomposition of system dynamics. We also
study a synthesis problem by engineering the system-environment coupling and
Hamiltonian engineering. We apply the theory to investigate an optomechanical
dark mode.


title: A microlocal characterization of Lipschitz continuity

abstract:
  We study continuous maps between differential manifolds from a microlocal
point of view. In particular, we characterize the Lipschitz continuity of these
maps in terms of the microsupport of the constant sheaf on their graph.
Furthermore, we give lower and upper bounds on the microsupport of the graph of
a continuous map and use these bounds to characterize strict differentiability
in microlocal terms.


title:
An Overview on Resource Allocation Techniques for Multi-User MIMO
  Systems

abstract:
  Remarkable research activities and major advances have been occurred over the
past decade in multiuser multiple-input multiple-output (MU-MIMO) systems.
Several transmission technologies and precoding techniques have been developed
in order to exploit the spatial dimension so that simultaneous transmission of
independent data streams reuse the same radio resources. The achievable
performance of such techniques heavily depends on the channel characteristics
of the selected users, the amount of channel knowledge, and how efficiently
interference is mitigated. In systems where the total number of receivers is
larger than the number of total transmit antennas, user selection becomes a key
approach to benefit from multiuser diversity and achieve full multiplexing
gain. The overall performance of MU-MIMO systems is a complex joint
multi-objective optimization problem since many variables and parameters have
to be optimized, including the number of users, the number of antennas, spatial
signaling, rate and power allocation, and transmission technique. The objective
of this literature survey is to provide a comprehensive overview of the various
methodologies used to approach the aforementioned joint optimization task in
the downlink of MU-MIMO communication systems.


title: Light-by-light scattering sum rules in light of new data

abstract:
  We evaluate the light-quark meson contributions to three exact light-by-light
scattering sum rules in light of new data by the Belle Collaboration, which
recently has extracted the transition form factors of the tensor meson
$f_2(1270)$ as well as of the scalar meson $f_0(980)$. We confirm a previous
finding that the $\eta, \eta^\prime$ and helicity-2 $f_2(1270)$ contributions
saturate one of these sum rules up to photon virtualities around 1 GeV$^2$. At
larger virtualities, our sum rule analysis shows an important contribution of
the $f_2(1565)$ meson and provides a first empirical extraction of its
helicity-2 transition form factor. Two further sum rules allow us to predict
the helicity-0 and helicity-1 transition form factors of the $f_2(1270)$ meson.
Furthermore, our analysis also provides an update for the scalar and tensor
meson hadronic light-by-light contributions to the muon's anomalous magnetic
moment.


title: Optimal Control for Speed Harmonization of Automated Vehicles

abstract:
  This article addresses the problem of controlling the speed of a number of
automated vehicles before they enter a speed reduction zone on a freeway. We
formulate the control problem and provide an analytical, closed-form solution
that can be implemented in real time. The solution yields the optimal
acceleration/deceleration of each vehicle under the hard safety constraint of
rear-end collision avoidance. The effectiveness of the solution is evaluated
through a microscopic simulation testbed and it is shown that the proposed
approach reduces significantly both fuel consumption and travel time. In
particular, for three different traffic volume levels, fuel consumption for
each vehicle is reduced by 19-22% compared to the baseline scenario, where
human-driven vehicles are considered, by 12-17% compared to the variable speed
limit (VSL) algorithm, and by 18-34% compared to the vehicular-based speed
harmonization (SPD-HARM) algorithm. Similarly, travel time is improved by
26-30% compared to the baseline scenario, by 3-19% compared to the VSL
algorithm, and by 31-39% compared to the vehicular-based SPD-HARM algorithm.


title:
Towards a Framework for Tracking Multiple Targets: Hybrid Systems meets
  Computational Geometry

abstract:
  We investigate a variation of the art gallery problem in which a team of
mobile guards tries to track an unpredictable intruder in a simply-connected
polygonal environment. In this work, we use the deployment strategy for
diagonal guards originally proposed in [1]. The guards are confined to move
along the diagonals of a polygon and the intruder can move freely within the
environment. We define critical regions to generate event-triggered strategies
for the guards. We design a hybrid automaton based on the critical regions to
model the tracking problem. Based on reachability analysis, we provide
necessary and sufficient conditions for tracking in terms of the maximal
controlled invariant set of the hybrid system. We express these conditions in
terms of the critical curves to find sufficient conditions for n/4 guards to
track the mobile intruder using the reachability analysis.


title: Some classifiable groupoid C*-algebras with prescribed K-theory

abstract:
  Given a simple, acyclic dimension group $G_{0}$ and countable, torsion-free,
abelian group $G_{1}$, we construct a minimal, amenable, \'{e}tale equivalence
relation $R$ on a Cantor set whose associated groupoid $C^{*}$-algebra,
$C^{*}(R)$, is tracially AF, and hence classifiable in the Elliott
classification scheme for simple, amenable, separable $C^{*}$-algebras, and
with $K_{*}(C^{*}(R)) \cong(G_{0}, G_{1})$.


title: Black Holes and Random Matrices

abstract:
  We argue that the late time behavior of horizon fluctuations in large anti-de
Sitter (AdS) black holes is governed by the random matrix dynamics
characteristic of quantum chaotic systems. Our main tool is the
Sachdev-Ye-Kitaev (SYK) model, which we use as a simple model of a black hole.
We use an analytically continued partition function $|Z(\beta +it)|^2$ as well
as correlation functions as diagnostics. Using numerical techniques we
establish random matrix behavior at late times. We determine the early time
behavior exactly in a double scaling limit, giving us a plausible estimate for
the crossover time to random matrix behavior. We use these ideas to formulate a
conjecture about general large AdS black holes, like those dual to 4D
super-Yang-Mills theory, giving a provisional estimate of the crossover time.
We make some preliminary comments about challenges to understanding the late
time dynamics from a bulk point of view.


title: Hints of new physics from stars

abstract:
  We review and update the current status of the observed anomalies in stellar
cooling and their interpretation in terms of axions and axion like particles.


title: IAXO, next-generation of helioscopes

abstract:
  The International Axion Observatory (IAXO) is a forth generation axion
helioscope designed to detect solar axions and axion-like particles (ALPs) with
a coupling to the photon $g_{a\gamma}$ down to a few $10^{-12}$ GeV$^{-1}$, 1.5
orders of magnitude beyond the current best astrophysical and experimental
upper bounds. This range includes parameter values invoked in the context of
the observed anomalies in light propagation over astronomical distances and to
explain the excessive cooling observed in a number of stellar objects. Here we
review the status of the IAXO project and of its potential to probe the most
physically motivated regions of the axion/ALPs parameter space.

categories: physics.ins-det astro-ph.IM astro-ph.SR hep-ex hep-ph


title:
Event Detection and Localization in Distribution Grids with Phasor
  Measurement Units

abstract:
  The recent introduction of synchrophasor technology into power distribution
systems has given impetus to various monitoring, diagnostic, and control
applications, such as system identification and event detection, which are
crucial for restoring service, preventing outages, and managing equipment
health. Drawing on the existing framework for inferring topology and
admittances of a power network from voltage and current phasor measurements,
this paper proposes an online algorithm for event detection and localization in
unbalanced three-phase distribution systems. Using a convex relaxation and a
matrix partitioning technique, the proposed algorithm is capable of identifying
topology changes and attributing them to specific categories of events. The
performance of this algorithm is evaluated on a standard test distribution
feeder with synthesized loads, and it is shown that a tripped line can be
detected and localized in an accurate and timely fashion, highlighting its
potential for real-world applications.


title:
Asymptotic Performance Analysis of Majority Sentiment Detection in
  Online Social Networks

abstract:
  We analyze the problem of majority sentiment detection in Online Social
Networks (OSN), and relate the detection error probability to the underlying
graph of the OSN. Modeling the underlying social network as an Ising Markov
random field prior based on a given graph, we show that in the case of the
empty graph (independent sentiments) and the chain graph, the detection is
always inaccurate, even when the number of users grow to infinity. In the case
of the complete graph, the detection is inaccurate if the connection strength
is below a certain critical value, while it is asymptotically accurate if the
strength is above that critical value, which is analogous to the phase
transition phenomenon in statistical physics.


title:
Motion Estimated-Compensated Reconstruction with Preserved-Features in
  Free-Breathing Cardiac MRI

abstract:
  To develop an efficient motion-compensated reconstruction technique for
free-breathing cardiac magnetic resonance imaging (MRI) that allows
high-quality images to be reconstructed from multiple undersampled single-shot
acquisitions. The proposed method is a joint image reconstruction and motion
correction method consisting of several steps, including a non-rigid motion
extraction and a motion-compensated reconstruction. The reconstruction includes
a denoising with the Beltrami regularization, which offers an ideal compromise
between feature preservation and staircasing reduction. Results were assessed
in simulation, phantom and volunteer experiments. The proposed joint image
reconstruction and motion correction method exhibits visible quality
improvement over previous methods while reconstructing sharper edges. Moreover,
when the acceleration factor increases, standard methods show blurry results
while the proposed method preserves image quality. The method was applied to
free-breathing single-shot cardiac MRI, successfully achieving high image
quality and higher spatial resolution than conventional segmented methods, with
the potential to offer high-quality delayed enhancement scans in challenging
patients.


abstract:
  Some of the most known integral inequalities are the Sobolev, Hardy and
Rellich inequalities in Euclidean spaces. In the context of submanifolds, the
Sobolev inequality was proved by Michael-Simon and Hoffman-Spruck. Since then,
a sort of applications to the submanifold theory has been derived from those
inequalities. Years later, Carron obtained a Hardy inequality for submanifolds
in Hadamard spaces. In this paper, we prove the general Hardy and Rellich
Inequalities for submanifolds in Hadamard spaces. Some applications are given
and we also analyse the equality cases.


title:
Electron-impact excitation of N$^{3+}$ using the B-spline R-matrix
  method: Importance of the target structure description and the size of the
  close-coupling expansion

abstract:
  There are major discrepancies between recent ICFT (Intermediate Coupling
Frame Transformation) and DARC (Dirac Atomic R-matrix Code) calculations
(Fern\'andez-Menchero et al. 2014, Astron. Astroph. 566 A104, Aggarwal et al.
2016 Mon. Not. R Astr. Soc. 461 3997) regarding electron-impact excitation
rates for transitions in several Be-like ions, as well as claims that the DARC
calculations are much more accurate and the ICFT results might even be wrong.
To identify possible reasons for these discrepancies and to estimate the
accuracy of the various results, we carried out independent B-Spline R-Matrix
(BSR) calculations for electron-impact excitation of the Be-like ion N$^{3+}$.
Our close-coupling expansions contain the same target states (238 levels
overall) as the previous ICFT and DARC calculations, but the representation of
the target wave functions is completely different. We find close agreement
among all calculations for the strong transitions between low-lying states,
whereas there remain serious discrepancies for the weak transitions as well as
for transitions to highly excited states. The differences in the final results
for the collision strengths are mainly due to differences in the structure
description, specifically the inclusion of correlation effects, rather than the
treatment of relativistic effects or problems with the validity of the three
methods to describe the collision. Hence there is no indication that one
approach is superior to another, until the convergence of both the target
configuration and the close-coupling expansions have been fully established.


title: Finite-Energy Sum Rules in Eta Photoproduction off the Nucleon

abstract:
  The reaction ${\gamma}N \to {\eta}N$ is studied in the high-energy regime
(with photon lab energies $E_{\gamma}^{\textrm{lab}} > 4$ GeV) using
information from the resonance region through the use of finite-energy sum
rules (FESR). We illustrate how analyticity allows one to map the t-dependence
of the unknown Regge residue functions. We provide predictions for the energy
dependence of the beam asymmetry at high energies.


title:
The radial distributions of the two main-sequence components in the
  young massive star cluster NGC 1856

abstract:
  The recent discovery of double main sequences in the young, massive star
cluster NGC 1856 has caught significant attention. The observations can be
explained by invoking two stellar generations with different ages and
metallicities or by a single generation of stars composed of two populations
characterized by different rotation rates. We analyzed the number ratios of
stars belonging to both main-sequence components in NGC 1856 as a function of
radius. We found that their number ratios remain approximately unchanged from
the cluster's central region to its periphery, indicating that both components
are homogeneously distributed in space. Through a comparison of the loci of the
best-fitting isochrones with the ridge lines of both stellar components, we
found that both multiple stellar populations and rapid stellar rotation can
potentially explain the observed main-sequence bifurcation in NGC 1856.
However, if NGC1856 were a young representative of the old globular clusters,
then the multiple stellar populations model would not be able to explain the
observed homogeneity in the spatial distributions of these two components,
since all relevant scenarios would predict that the second stellar generation
should be formed in a more compact configuration than that of the first stellar
generation, while NGC 1856 is too young for both stellar generations to have
been fully mixed dynamically. We speculate that the rapid stellar rotation
scenario would be the favored explanation of the observed multiple stellar
sequences in NGC 1856.


title: Causal Inference in Observational Data

abstract:
  Our aging population increasingly suffers from multiple chronic diseases
simultaneously, necessitating the comprehensive treatment of these conditions.
Finding the optimal set of drugs for a combinatorial set of diseases is a
combinatorial pattern exploration problem. Association rule mining is a popular
tool for such problems, but the requirement of health care for finding causal,
rather than associative, patterns renders association rule mining unsuitable.
To address this issue, we propose a novel framework based on the Rubin-Neyman
causal model for extracting causal rules from observational data, correcting
for a number of common biases. Specifically, given a set of interventions and a
set of items that define subpopulations (e.g., diseases), we wish to find all
subpopulations in which effective intervention combinations exist and in each
such subpopulation, we wish to find all intervention combinations such that
dropping any intervention from this combination will reduce the efficacy of the
treatment. A key aspect of our framework is the concept of closed intervention
sets which extend the concept of quantifying the effect of a single
intervention to a set of concurrent interventions. We also evaluated our causal
rule mining framework on the Electronic Health Records (EHR) data of a large
cohort of patients from Mayo Clinic and showed that the patterns we extracted
are sufficiently rich to explain the controversial findings in the medical
literature regarding the effect of a class of cholesterol drugs on Type-II
Diabetes Mellitus (T2DM).


title: Kaiser-Bessel Basis for the Particle-Mesh Interpolation

abstract:
  In this work, we introduce the Kaiser-Bessel interpolation basis for the
particle-mesh interpolation in the fast Ewald method. A reliable a priori error
estimate is developed to measure the accuracy of the force computation in
correlated charge systems, and is shown to be effective in optimizing the shape
parameter of the Kaiser-Bessel basis in terms of accuracy. By comparing the
optimized Kaiser-Bessel basis with the traditional B-spline basis, we
demonstrate that the former is more accurate than the latter in part of the
working parameter space, saying a relatively small real space cutoff, a
relatively small reciprocal space mesh and a relatively large truncation of
basis. In some cases, the Kaiser-Bessel basis is found to be more than one
order of magnitude more accurate.


title:
Control over emissivity of zero-static-power thermal emitters based on
  phase changing material GST

abstract:
  Controlling the emissivity of a thermal emitter has attracted growing
interest with a view towards a new generation of thermal emission devices. So
far, all demonstrations have involved sustained external electric or thermal
consumption to maintain a desired emissivity. Here control over the emissivity
of a thermal emitter consisting of a phase changing material Ge2Sb2Te5 (GST)
film on top of a metal film is demonstrated. This thermal emitter shows broad
wavelength-selective spectral emissivity in the mid-infrared. The peak
emissivity approaches the ideal blackbody maximum and a maximum extinction
ratio of above 10dB is attainable by switching GST between the crystalline and
amorphous phases. By controlling the intermediate phases, the emissivity can be
continuously tuned. This switchable, tunable, wavelength-selective and
thermally stable thermal emitter will pave the way towards the ultimate control
of thermal emissivity in the field of fundamental science as well as for
energy-harvesting and thermal control applications, including
thermophotovoltaics, light sources, infrared imaging and radiative coolers.


title:
Asymptotic formulae of two divergent bilateral basic hypergeometric
  series

abstract:
  We provide new formulae for the degenerations of the bilateral basic
hypergeometric function ${}_1\psi_1 ( a; b; q, z )$ with using the
$q$-Borel-Laplace transformation. These are thought of as the first step to
construct connection formulae of $q$-difference equation for ${}_1\psi_1 ( a;
b; q, z )$. Moreover, we show that our formulae have the $q \to 1 - 0$ limit.


title:
Convergence to the Mahler measure and the distribution of periodic
  points for algebraic Noetherian $\mathbb{Z}^d$-actions

abstract:
  For every $P \in \mathbb{Z}[x_1^{\pm 1}, \ldots, x_d^{\pm 1}] \setminus
\{0\}$, and every $\varepsilon > 0$, we prove that there are a computable
function $M = M(d,\varepsilon,\deg{P},h(P)) < \infty$ and a finite union $Z =
Z(d,\varepsilon,\deg{P},h(P))$ of proper torsion cosets $\boldsymbol{\mu} T
\subsetneq \mathbb{G}_m^d$ such that, for every $N \in \mathbb{N}$, $Z$
contains all but at most $M$ of the torsion points $\boldsymbol{\zeta} \in
\mu_N^d$ satisfying $|P(\boldsymbol{\zeta})| < e^{-\varepsilon \phi(N)}$. This
extends a well known structural theorem from torsion points lying exactly on a
variety to torsion points lying very near to the subvariety. As a consequence,
we prove that the averages of $\log{|P(\mathbf{x})|}$ over $\mu_N^d$ converge
as $N \to \infty$ to the Mahler measure of $P$.
  By the work of B. Kitchens, D. Lind, K. Schmidt and T. Ward, the convergence
consequence amounts to the following statement in dynamics: For every
Noetherian $\mathbb{Z}^d$-action $T : \mathbb{Z}^d \to \mathrm{Aut}(X)$ by
automorphisms of a compact abelian group $X$ having a finite topological
entropy $h(T)$, the exponential growth rate of the number of connected
components of the group $\mathrm{Per}_N(T)$ of $N \cdot \mathbb{Z}^d$-periodic
points of $(X,T)$ exists as $N \to \infty$, and equals the topological entropy
$h(T)$. Moreover, it follows that all weak-$*$ limit measures of the
push-forwards of the Haar measures on $\mathrm{Per}_N(T)$, under any a sequence
of positive integers $N$, are measures of maximum entropy $h(T)$.
  Our main arithmetic result extends to Diophantine approximation by points of
sufficiently small canonical height. It is best possible in such a generality,
where an exceptional set is an inevitable feature.


title:
A Physical Unclonable Function with Redox-based Nanoionic Resistive
  Memory

abstract:
  A unique set of characteristics are packed in emerging nonvolatile
reduction-oxidation (redox)-based resistive switching memories (ReRAMs) such as
their underlying stochastic switching processes alongside their intrinsic
highly nonlinear current-voltage characteristic, which in addition to known
nano-fabrication process variation make them a promising candidate for the next
generation of low-cost, low-power, tiny and secure Physically Unclonable
Functions (PUFs). This paper takes advantage of this otherwise disadvantageous
ReRAM feature using a combination of novel architectural and peripheral
circuitry. We present a physical one-way function, nonlinear resistive Physical
Unclonable Function (nrPUF), potentially applicable in variety of
cyber-physical security applications given its performance characteristics. We
experimentally verified performance of Valency Change Mechanism (VCM)-based
ReRAM in nano-fabricated crossbar arrays across multiple dies and runs. In
addition to a massive pool of Challenge-Response Pairs (CRPs), using a
combination of experimental and simulation, our proposed PUF shows a
reliability of 98.67%, a uniqueness of 49.85%, a diffuseness of 49.86%, a
uniformity of 47.28%, and a bit-aliasing of 47.48%.