pinecone/core-2020-05-10-deduplication huggingface dataset:
Inflationary Solution to the Strong CP and $\mu$ Problems

We show that the vacuum expectation value of the inflaton at the Peccei-Quinn
axion scale can generate the supersymmetric Higgs mass $\mu$ term. This
provides an inflationary simultaneous solution to the strong CP problem and the
$\mu$ problem of the Minimal Supersymmetric Standard Model, and gives a
testable prediction for the $\mu$ parameter: $\mu^2 \approx (0.25-0.5)m_0^2$,
where $m_0$ is the soft Higgs scalar mass. Our model involves a very small
Yukawa coupling of order $10^{-10}$, which could originate from an
extra-dimensional scenario or type I string theory.Comment: Version to appear in Physics Letters B. 14 page
Substellar Objects in Nearby Young Clusters VII: The substellar mass
  function revisited

The abundance of brown dwarfs (BDs) in young clusters is a diagnostic of star
formation theory. Here we revisit the issue of determining the substellar
initial mass function (IMF), based on a comparison between NGC1333 and IC348,
two clusters in the Perseus star-forming region. We derive their mass
distributions for a range of model isochrones, varying distances, extinction
laws and ages, with comprehensive assessments of the uncertainties. We find
that the choice of isochrone and other parameters have significant effects on
the results, thus we caution against comparing IMFs obtained using different
approaches. For NGC1333, we find that the star/BD ratio R is between 1.9 and
2.4, for all plausible scenarios, consistent with our previous work. For IC348,
R is between 2.9 and 4.0, suggesting that previous studies have overestimated
this value. Thus, the star forming process generates about 2.5-5 substellar
objects per 10 stars. The derived star/BD ratios correspond to a slope of the
power-law mass function of alpha=0.7-1.0 for the 0.03-1.0Msol mass range. The
median mass in these clusters - the typical stellar mass - is between
0.13-0.30Msol. Assuming that NGC1333 is at a shorter distance than IC348, we
find a significant difference in the cumulative distribution of masses between
the two clusters, resulting from an overabundance of very low mass objects in
NGC1333. Gaia astrometry will constrain the cluster distances better and will
lead to a more definitive conclusion. Furthermore, ratio R is somewhat larger
in IC348 compared with NGC1333, although this difference is still within the
margins of error. Our results indicate that environments with higher object
density may produce a larger fraction of very low mass objects, in line with
predictions for brown dwarf formation through gravitational fragmentation of
filaments falling into a cluster potential.Comment: 16 pages, 4 figures, accepted for publication in Ap
Higgs Boson Mass and Complex Snuetrino Dark Matter in the Supersymmetric
  Inverse Seesaw Models

The discovery of a relatively heavy Standard Model (SM) -like Higgs boson
challenges naturalness of the minimal supersymmetric standard model (MSSM) from
both Higgs and dark matter (DM) sectors. We study these two aspects in the MSSM
extended by the low-scale inverse seesaw mechanism. Firstly, it admits a
sizable radiative correction on the Higgs boson mass m_h, up to \sim 4 GeV in
the case of an IR-fixed point of the coupling Y_\nu LH_u\nu^c and a large
sneutrino mixing. Secondly, the lightest sneutrino, highly complex as expected,
is a viable thermal DM candidate. Owing to the correct relic density and
XENON100, two cases survive: a Higgs-portal complex DM with mass lying around
the Higgs pole or above $W$ threshold, and a coannihilating DM with slim
prospect of detection. Given an extra family of sneutrinos, both scenarios
naturally work when we attempt to suppress the DM left-handed sneutrino
component, confronting with enhancing m_h.Comment: 19 pages, 6 figures, JHEP versio
PyFR: An Open Source Framework for Solving Advection-Diffusion Type
  Problems on Streaming Architectures using the Flux Reconstruction Approach

High-order numerical methods for unstructured grids combine the superior
accuracy of high-order spectral or finite difference methods with the geometric
flexibility of low-order finite volume or finite element schemes. The Flux
Reconstruction (FR) approach unifies various high-order schemes for
unstructured grids within a single framework. Additionally, the FR approach
exhibits a significant degree of element locality, and is thus able to run
efficiently on modern streaming architectures, such as Graphical Processing
Units (GPUs). The aforementioned properties of FR mean it offers a promising
route to performing affordable, and hence industrially relevant,
scale-resolving simulations of hitherto intractable unsteady flows within the
vicinity of real-world engineering geometries. In this paper we present PyFR,
an open-source Python based framework for solving advection-diffusion type
problems on streaming architectures using the FR approach. The framework is
designed to solve a range of governing systems on mixed unstructured grids
containing various element types. It is also designed to target a range of
hardware platforms via use of an in-built domain specific language based on the
Mako templating engine. The current release of PyFR is able to solve the
compressible Euler and Navier-Stokes equations on grids of quadrilateral and
triangular elements in two dimensions, and hexahedral elements in three
dimensions, targeting clusters of CPUs, and NVIDIA GPUs. Results are presented
for various benchmark flow problems, single-node performance is discussed, and
scalability of the code is demonstrated on up to 104 NVIDIA M2090 GPUs. The
software is freely available under a 3-Clause New Style BSD license (see
www.pyfr.org)
Chemical reactions of conformationally selected molecules in a beam with
  Coulomb-crystallized ions

Many molecules exhibit multiple conformers that often easily interconvert
under thermal conditions. Therefore, single conformations are difficult to
isolate which renders the study of their distinct chemical reactivities
challenging. We have recently reported a new experimental method for the
characterization of conformer-specific effects in chemical reactions [Y. P.
Chang et al., Science 342, 98 (2013)]. Different conformers are spatially
separated using inhomogeneous electric fields and reacted with a Coulomb
crystal of cold, spatially localized ions in a trap. As a first application, we
studied reactions between the two conformers of 3-aminophenol and Ca$^+$. We
observed a twofold larger rate constant for the $cis$ compared to the $trans$
conformer which was rationalized in terms of the differences in the long-range
ion-molecule interactions. The present article provides a detailed description
of the new method and a full account of the experimental results as well as the
accompanying theoretical calculations.Comment: 12 pages, 11 figure
Non-renormalization theorems and N=2 supersymmetric backgrounds

The conditions for fully supersymmetric backgrounds of general N=2 locally
supersymmetric theories are derived based on the off-shell superconformal
multiplet calculus. This enables the derivation of a non-renormalization
theorem for a large class of supersymmetric invariants with higher-derivative
couplings. The theorem implies that the invariant and its first order variation
must vanish in a fully supersymmetric background. The conjectured relation of
one particular higher-derivative invariant with a specific five-dimensional
invariant containing the mixed gauge-gravitational Chern-Simons term is
confirmed.Comment: 30 pages; v2: minor correction
A high-statistics measurement of transverse spin effects in dihadron
  production from muon-proton semi-inclusive deep-inelastic scattering

A measurement of the azimuthal asymmetry in dihadron production in
deep-inelastic scattering of muons on transversely polarised proton (NH$_{3}$)
targets are presented. They provide independent access to the transversity
distribution functions through the measurement of the Collins asymmetry in
single hadron production. The data were taken in the year $2010$ with the
COMPASS spectrometer using a $160\,\mbox{GeV}/c$ muon beam of the CERN SPS,
increasing by a factor of about three the available statistics of the
previously published data taken in the year $2007$. The measured sizeable
asymmetry is in good agreement with the published data. An approximate equality
of the Collins asymmetry and the dihadron asymmetry is observed, suggesting a
common physical mechanism in the underlying fragmentation.Comment: 14 pages, 8 figure
Reconstructing the stellar mass distributions of galaxies using S4G IRAC
  3.6 and 4.5 micron images: II. The conversion from light to mass

We present a new approach for estimating the 3.6 micron stellar mass-to-light
ratio in terms of the [3.6]-[4.5] colors of old stellar populations. Our
approach avoids several of the largest sources of uncertainty in existing
techniques. By focusing on mid-IR wavelengths, we gain a virtually dust
extinction-free tracer of the old stars, avoiding the need to adopt a dust
model to correctly interpret optical or optical/NIR colors normally leveraged
to assign M/L. By calibrating a new relation between NIR and mid-IR colors of
GLIMPSE giant stars we also avoid discrepancies in model predictions for the
[3.6]-[4.5] colors of old stellar populations due to uncertainties in molecular
line opacities. We find that the [3.6]-[4.5] color, which is driven primarily
by metallicity, provides a tight constraint on M/L_3.6, which varies
intrinsically less than at optical wavelengths. The uncertainty on M/L_3.6 of
~0.07 dex due to unconstrained age variations marks a significant improvement
on existing techniques for estimating the stellar M/L with shorter wavelength
data. A single M/L_3.6=0.6 (assuming a Chabrier IMF), independent of
[3.6]-[4.5] color, is also feasible as it can be applied simultaneously to old,
metal-rich and young, metal-poor populations, and still with comparable (or
better) accuracy (~0.1 dex) as alternatives. We expect our M/L_3.6 to be
optimal for mapping the stellar mass distributions in S4G galaxies, for which
we have developed an Independent Component Analysis technique to first isolate
the old stellar light at 3.6 micron from non-stellar emission (e.g. hot dust
and the 3.3 PAH feature). Our estimate can also be used to determine the
fractional contribution of non-stellar emission to global (rest-frame) 3.6
micron fluxes, e.g. in WISE imaging, and establishes a reliable basis for
exploring variations in the stellar IMF.Comment: 14 pages, 6 figures, accepted for publication in Ap
Natural Supersymmetry and Dynamical Flavour with Metastable Vacua

We show how gauged flavour breaking and N = 1 supersymmetry breaking can be
dynamically aligned to produce natural models. Supersymmetry is broken in a
metastable vacuum, while a weakly gauged flavour symmetry is identified with an
SU(3)_F subgroup of the global symmetry of the SQCD model. We find that
alignment can easily occur either through strongly coupled flavour models, with
SQCD bound states playing the role of flavons, or entirely weakly coupled and
renormalizable models with elementary SU(3)_F adjoint flavons. In both cases it
is essential that the SU(3)_F breaking, and hence all the flavour structure, is
driven dynamically by the SUSY breaking. The resulting flavour gauge mediation
in conjunction with the usual gauge mediation contribution leads to naturally
light third generations squarks, with first and second generations above
exclusions.Comment: 24 pages, 10 figure
F-GUTs with Mordell-Weil U(1)'s

In this note we study the constraints on F-theory GUTs with extra $U(1)$'s in
the context of elliptic fibrations with rational sections. We consider the
simplest case of one abelian factor (Mordell-Weil rank one) and investigate the
conditions that are induced on the coefficients of its Tate form. Converting
the equation representing the generic hypersurface $P_{112}$ to this Tate's
form we find that the presence of a U(1), already in this local description, is
consistent with the exceptional ${\cal E}_6$ and ${\cal E}_7$ non-abelian
singularities. We briefly comment on a viable ${\cal E}_6\times U(1)$ effective
F-theory model.Comment: 13 page
Divergences in the quark number susceptibility : The origin and a cure

Quark number susceptibility on the lattice, obtained by merely adding a $\mu
N$ term with $\mu$ as the chemical potential and $N$ as the conserved quark
number, has a quadratic divergence in the cut-off $a$. We show that such a
divergence already exist for free fermions with a cut-off regulator. While one
can eliminate it in the free lattice theory by suitably modifying the action,
as is popularly done, it can simply be subtracted off as well. Computations of
higher order susceptibilities, needed for estimating the location of the QCD
critical point, then need a lot fewer number of quark propagators at any order.
We show that this method of divergence removal works in the interacting theory.Comment: Published version, with added discussion of the results and the
  appendix remove
A model of stable chromomagnetic vacuum in higher-dimensional Yang-Mills theory

We study the effective action in Euclidean Yang-Mills theory with a compact simple gauge group in one-loop approximation assuming a covariantly constant gauge field strength as a background. For groups of higher rank and spacetimes of higher dimensions such field configurations have many independent color components taking values in Cartan subalgebra and many ``magnetic fields'' in each color component. In our previous investigation it was shown that such background is stable in dimensions higher than four provided the amplitudes of ``magnetic fields'' do not differ much from each other. In present paper we calculate exactly the relevant zeta-functions in the case of equal amplitudes of ``magnetic fields''. For the case of two ``magnetic fields'' with equal amplitudes the behavior of the effective action is studied in detail. It is shown that in dimensions d=4,5,6,7 ({\rm mod}\, 8), the perturbative vacuum is metastable, i.e., it is stable in perturbation theory but the effective action is not bounded from below, whereas in dimensions d=9,10,11 ({\rm mod}\, 8) the perturbative vacuum is absolutely stable. In dimensions d=8 ({\rm mod}\, 8) the perturbative vacuum is stable for small values of coupling constant but becomes unstable for large coupling constant leading to the formation of a non-perturbative stable vacuum with nonvanishing ``magnetic fields''. The critical value of the coupling constant and the amplitudes of the vacuum ``magnetic fields'' are evaluated exactly
Quantization of N=1 chiral/nonminimal (CNM) scalar multiplets and
  supersymmetric Yang-Mills theories

We give the superfield quantization of chiral/nonminimal (CNM) scalar
multiplets defined by pairs of N=1 chiral and complex linear scalar superfields
kinematically coupled. In the pure massive case we develop the covariant
quantization when CNM multiplets are coupled to background gauge superfields.
Furthermore, we study some properties of N=1 supersymmetric Yang--Mills
theories constructed using CNM scalar matter superfields. In particular, we
compute the one--loop contribution to the effective action for the matter
superfields, we study the analogue of the Konishi anomaly and discuss some
properties of the glueball superpotential.Comment: 15 pages, LaTeX, references added, new comments in section 2, section
  4 modified, new section 6 inserted, version to appear on Phys. Lett.
N=1 Heterotic/F-Theory Duality

We review aspects of N=1 duality between the heterotic string and F-theory. After a description of string duality intended for the non-specialist the framework and the constraints for heterotic/F-theory compactifications are presented. The computations of the necessary Calabi-Yau manifold and vector bundle data, involving characteristic classes and bundle moduli, are given in detail. The matching of the spectrum of chiral multiplets and of the number of heterotic five-branes respectively F-theory three-branes, needed for anomaly cancellation in four-dimensional vacua, is pointed out. Several examples of four-dimensional dual pairs are constructed where on both sides the geometry of the involved manifolds relies on del Pezzo surfaces
All the supersymmetric configurations of N=4,d=4 supergravity

All the supersymmetric configurations of pure, ungauged, N=4,d=4 supergravity
are classified in a formalism that keeps manifest the S and T dualities of the
theory. We also find simple equations that need to be satisfied by the
configurations to be classical solutions of the theory. While the solutions
associated to null Killing vectors were essentially classified by Tod (a
classification that we refine), we find new configurations and solutions
associated to timelike Killing vectors that do not satisfy Tod's rigidity
hypothesis (hence, they have a non-trivial U(1) connection) and whose
supersymmetry projector is associated to 1-dimensional objects (strings),
although they have a trivial axion field.Comment: Latex file, 47 pages. References added and a few non-essential
  misprints correcte
Dyson-Schwinger Equation: Density, Temperature and Continuum Strong QCD

Continuum strong QCD is the application of models and continuum quantum field theory to the study of phenomena in hadronic physics, which includes; e.g., the spectrum of QCD bound states and their interactions; and the transition to, and properties of, a quark gluon plasma. We provide a contemporary perspective, couched primarily in terms of the Dyson-Schwinger equations but also making comparisons with other approaches and models. Our discourse provides a practitioners' guide to features of the Dyson-Schwinger equations [such as confinement and dynamical chiral symmetry breaking] and canvasses phenomenological applications to light meson and baryon properties in cold, sparse QCD. These provide the foundation for an extension to hot, dense QCD, which is probed via the introduction of the intensive thermodynamic variables: chemical potential and temperature. We describe order parameters whose evolution signals deconfinement and chiral symmetry restoration, and chronicle their use in demarcating the quark gluon plasma phase boundary and characterising the plasma's properties. Hadron traits change in an equilibrated plasma. We exemplify this and discuss putative signals of the effects. Finally, since plasma formation is not an equilibrium process, we discuss recent developments in kinetic theory and its application to describing the evolution from a relativistic heavy ion collision to an equilibrated quark gluon plasma
Supersingular primes for points on $X_0(p)/w_p$

For small odd primes $p$, we prove that most of the rational points on the
modular curve $X_0(p)/w_p$ parametrize pairs of elliptic curves having
infinitely many supersingular primes. This result extends the class of elliptic
curves for which the infinitude of supersingular primes is known. We give
concrete examples illustrating how these techniques can be explicitly used to
construct supersingular primes for such elliptic curves. Finally, we discuss
generalizations to points defined over larger number fields and indicate the
types of obstructions that arise for higher level modular curves
The GALEX Ultraviolet Virgo Cluster Survey (GUViCS). V. Ultraviolet
  diffuse emission and cirrus properties in the Virgo cluster direction

CONTEXT: The Virgo direction has been observed at many wavelengths in the
recent years, in particular in the ultraviolet with GALEX. The far ultraviolet
(FUV) diffuse light detected by GALEX bears interesting information on the
large scale distribution of Galactic dust, owing to the GALEX FUV band
sensitivity and resolution. AIMS: We aim to characterise the ultraviolet large
scale distribution of diffuse emission in the Virgo direction. A map of this
emission may become useful for various studies by identifying regions where
dust affects observations by either scattering light or absorbing radiation.
METHODS: We construct mosaics of the FUV and near ultraviolet diffuse emission
over a large sky region (RA 12 to 13 hours, DEC 0 to 20 degrees) surrounding
the Virgo cluster, using all the GALEX available data in the area. We test for
the first time the utilisation of the FUV diffuse light as a Galactic
extinction E(B-V) tracer. RESULTS: The FUV diffuse light scattered on cirrus
reveals details in their geometry. Despite a large dispersion, the FUV diffuse
light correlates roughly with other Galactic dust tracers (coming from IRAS,
Herschel, Planck), offering an opportunity to use the FUV emission to locate
them in future studies with a better resolution (about 5 arcsec native
resolution, 20 arcsec pixels maps presented in this paper) than several usual
tracers. Estimating the Galactic dust extinction on the basis of this emission
allows us to find a smaller dispersion in the NUV-i colour of background
galaxies at a given E(B-V)than with other tracers. The diffuse light mosaics
obtained in this work are made publicly available.Comment: Accepted in Astronomy and Astrophysics, 11 pages, 12 figure
Spectral caustics in laser assisted Breit-Wheeler process

Electron-positron pair production by the Breit-Wheeler process embedded in a
strong laser pulse is analyzed. The transverse momentum spectrum displays
prominent peaks which are interpreted as caustics, the positions of which are
accessible by the stationary phases. Examples are given for the superposition
of an XFEL beam with an optical high-intensity laser beam. Such a configuration
is available, e.g., at LCLS at present and at European XFEL in near future. It
requires a counter propagating probe photon beam with high energy which can be
generated by synchronized inverse Compton backscattering