pinecone/core-2020-05-10-deduplication huggingface dataset:
Polarized Structure of Nucleon in the Valon Representation

We have utilized the concept of valon model to calculate the spin structure
functions of proton, neutron and deuteron. The valon structure itself is
universal and arises from the perturbative dressing of the valence quark in
QCD. Our results agree rather well with all the relevant experimental data on
$g_{1}^{p, n, d}$ and $g_{A}/g_{v}$, and suggests that the sea quark
contribution to the spin of proton is consistent with zero. It also reveals
that while the total quark contribution to the spin of valon is almost constant
at $Q^{2}>=1$ the gluon contribution grows with the increase of $Q^2$ and hence
requiring a sizable negative orbital angular momentum component $L_z$. This
component along with the singlet and non-singlet parts are calculated in the
Next-to-Leading order in QCD. We speculate that gluon contribution to the spin
content of the proton is about 60% for all $Q^2$ values. Finally, we show that
the size of gluon polarization and hence, $L_{z}$, is sensitive to the initial
scale$Q_{0}^{2}$.Comment: 24 pages, 9 Figure
Analytical study on holographic superconductors in external magnetic
  field

We investigate the holographic superconductors immersed in an external
magnetic field by using the analytical approach. We obtain the spatially
dependent condensate solutions in the presence of the magnetism and find
analytically that the upper critical magnetic field satisfies the relation
given in the Ginzburg-Landau theory. We observe analytically the reminiscent of
the Meissner effect where the magnetic field expels the condensate. Extending
to the D-dimensional Gauss-Bonnet AdS black holes, we examine the influence
given by the Gauss-Bonnet coupling on the condensation. Different from the
positive coupling, we find that the negative Gauss-Bonnet coupling enhances the
condensation when the external magnetism is not strong enough.Comment: revised version, to appear in JHE
Deformed Quantum Cohomology and (0,2) Mirror Symmetry

We compute instanton corrections to correlators in the genus-zero topological
subsector of a (0,2) supersymmetric gauged linear sigma model with target space
P1xP1, whose left-moving fermions couple to a deformation of the tangent
bundle. We then deduce the theory's chiral ring from these correlators, which
reduces in the limit of zero deformation to the (2,2) ring. Finally, we compare
our results with the computations carried out by Adams et al.[ABS04] and Katz
and Sharpe[KS06]. We find immediate agreement with the latter and an
interesting puzzle in completely matching the chiral ring of the former.Comment: AMSLatex, 30 pages, one eps figure. V4: typos corrected, final
  version appearing in JHE
Geodesic motion in the space-time of a cosmic string

We study the geodesic equation in the space-time of an Abelian-Higgs string
and discuss the motion of massless and massive test particles. The geodesics
can be classified according to the particles energy, angular momentum and
linear momentum along the string axis. We observe that bound orbits of massive
particles are only possible if the Higgs boson mass is smaller than the gauge
boson mass, while massless particles always move on escape orbits. Moreover,
neither massive nor massless particles can ever reach the string axis for
non-vanishing angular momentum. We also discuss the dependence of light
deflection by a cosmic string as well as the perihelion shift of bound orbits
of massive particles on the ratio between Higgs and gauge boson mass and the
ratio between symmetry breaking scale and Planck mass, respectively.Comment: 20 pages including 14 figures; v2: references added, discussion on
  null geodesics extended, numerical results adde
On domain walls in a Ginzburg-Landau non-linear S^2-sigma model

The domain wall solutions of a Ginzburg-Landau non-linear $S^2$-sigma hybrid
model are unveiled. There are three types of basic topological walls and two
types of degenerate families of composite - one topological, the other
non-topological- walls. The domain wall solutions are identified as the finite
action trajectories (in infinite time) of a related mechanical system that is
Hamilton-Jacobi separable in sphero-conical coordinates. The physical and
mathematical features of these domain walls are thoroughly discussed.Comment: 26 pages, 18 figure
Inelastic processes in DIS and N=4 SYM

In this paper we compare the prediction for deep inelastic scattering from
N=4 SYM with the HERA experimental data. The paper conveys two results. The
first is the message that N=4 SYM is able to describe the DIS data with very
good accuracy ($\chi^2/d.o.f. \,\leq\,1.5$) in the region of $Q^2 = 0.85 \div
60\,GeV^2$ with $2/\sqrt{\lambda} = 0.7 \div 0.8 $ . The second is that the
value of string coupling constant $g_s$ turns out to be so small that none of
saturation effects will be visible in the region of accessible energies,
including the maximal energy of the LHC (W = 14 \,\,TeV).Comment: 13 pp., 7 figures in eps forma
Three-loop HTL gluon thermodynamics at intermediate coupling

We calculate the thermodynamic functions of pure-glue QCD to three-loop order
using the hard-thermal-loop perturbation theory (HTLpt) reorganization of
finite temperature quantum field theory. We show that at three-loop order
hard-thermal-loop perturbation theory is compatible with lattice results for
the pressure, energy density, and entropy down to temperatures $T\simeq3\;T_c$.
Our results suggest that HTLpt provides a systematic framework that can used to
calculate static and dynamic quantities for temperatures relevant at LHC.Comment: 24 pages, 13 figs. 2nd version: improved discussion and fixing typos.
  Published in JHE
Supersymmetric AdS3 X S2 M-theory geometries with fluxes

Motivated by a recent observation that the LLM geometries admit 1/4-BPS
M5-brane probes with worldvolume AdS3 X \Sigma_2 X S1 preserving the
R-symmetry, we initiate a classification of the most general AdS3 X S2
geometries in M-theory. We retain all field strengths consistent with symmetry
and derive the torsion conditions for M_6 in terms of two linearly independent
spinors. Surprisingly, we identify three Killing directions for M_6, but only
two of these generate isometries of the overall ansatz. We show that the
existence of this third direction depends on the norm of the spinors. Then,
specialising to the case where the spinors define an SU(2)-structure and the
class of solutions is 1/4-BPS, we note that supersymmetry dictates that all
magnetic fluxes necessarily thread the S2. Finally, by assuming that the two
remaining Killing directions are parallel and aligned with one of the two
vectors defining the SU(2)-structure, we derive a general relationship for the
two spinors before extracting a known class of solutions from the torsion
conditions.Comment: 32 pages, minor correction
An A4 flavor model for quarks and leptons in warped geometry

We propose a spontaneous A4 flavor symmetry breaking scheme implemented in a
warped extra dimensional setup to explain the observed pattern of quark and
lepton masses and mixings. The main advantages of this choice are the
explanation of fermion mass hierarchies by wave function overlaps, the
emergence of tribimaximal neutrino mixing and zero quark mixing at the leading
order and the absence of tree-level gauge mediated flavor violations. Quark
mixing is induced by the presence of bulk flavons, which allow for cross-brane
interactions and a cross-talk between the quark and neutrino sectors, realizing
the spontaneous symmetry breaking pattern A4 --> nothing first proposed in
[X.G.\,He, Y.Y.\,Keum, R.R.\,Volkas, JHEP{0604}, 039 (2006)]. We show that the
observed quark mixing pattern can be explained in a rather economical way,
including the CP violating phase, with leading order cross-interactions, while
the observed difference between the smallest CKM entries V_{ub} and V_{td} must
arise from higher order corrections. We briefly discuss bounds on the
Kaluza-Klein scale implied by flavor changing neutral current processes in our
model and show that the residual little CP problem is milder than in flavor
anarchic models.Comment: 34 pages, 2 figures; version published in JHE
Partially Supersymmetric Composite Higgs Models

We study the idea of the Higgs as a pseudo-Goldstone boson within the
framework of partial supersymmetry in Randall-Sundrum scenarios and their CFT
duals. The Higgs and third generation of the MSSM are composites arising from a
strongly coupled supersymmetric CFT with global symmetry SO(5) spontaneously
broken to SO(4), whilst the light generations and gauge fields are elementary
degrees of freedom whose couplings to the strong sector explicitly break the
global symmetry as well as supersymmetry. The presence of supersymmetry in the
strong sector may allow the compositeness scale to be raised to ~10 TeV without
fine tuning, consistent with the bounds from precision electro-weak
measurements and flavour physics. The supersymmetric flavour problem is also
solved. At low energies, this scenario reduces to the "More Minimal
Supersymmetric Standard Model" where only stops, Higgsinos and gauginos are
light and within reach of the LHC.Comment: 28 pages. v2 minor changes and Refs. adde
Robust Cosmological Bounds on Neutrinos and their Combination with
  Oscillation Results

We perform a global analysis of cosmological observables in generalized
cosmologies which depart from $\Lambda$CDM models by allowing non-vanishing
curvature $\Omega_k\neq 0$, dark energy with equation of state with $\omega\neq
-1$, the presence of additional relativistic degrees of freedom $\Delta N_{\rm
rel}$, and neutrino masses $\Omega_\nu\neq 0$. By combining the data from
cosmic microwave background (CMB) experiments (in particular the latest results
from WMAP-7), the present day Hubble constant (H0) measurement, the
high-redshift Type-I supernovae (SN) results and the information from large
scale structure (LSS) surveys, we determine the parameters in the
10-dimensional parameter space for such models. We present the results from the
analysis when the full shape information from the LSS matter power spectrum
(LSSPS) is included versus when only the corresponding distance measurement
from the baryon acoustic oscillations (BAO) is accounted for. We compare the
bounds on the neutrino mass scale in these generalized scenarios with those
obtained for the 6+1 parameter analysis in $\Lambda{\rm CDM}+m_\nu$ models and
we also study the dependence of those on the set of observables included in the
analysis. Finally we combine these results with the information on neutrino
mass differences and mixing from the global analysis of neutrino oscillation
experiments and derive the presently allowed ranges for the two laboratory
probes of the absolute scale of neutrino mass: the effective electron neutrino
mass in single beta decay and the effective Majorana neutrino mass in
neutrinoless $\beta\beta$ decay.Comment: 19 pages, 4 figures. Acknowledgments correcte
Topological Anti-Topological Fusion in Four-Dimensional Superconformal
  Field Theories

We present some new exact results for general four-dimensional superconformal
field theories. We derive differential equations governing the coupling
constant dependence of chiral primary correlators. For N=2 theories we show
that the Zamolodchikov metric on the moduli space and the operator mixing of
chiral primaries are quasi-topological quantities and constrained by
holomorphy. The equations that we find are the four-dimensional analogue of the
tt* equations in two-dimensions, discovered by the method of "topological
anti-topological fusion" by Cecotti and Vafa. Our analysis relies on conformal
perturbation theory and the superconformal Ward identities and does not use a
topological twist.Comment: 43 pages (29 pages + 4 appendices), 2 figures, harvmac, v2: fixed
  typos, improved some derivations, numerical coefficients in tt* equations
  correcte
Glueball masses in the large N limit

The lowest-lying glueball masses are computed in SU($N$) gauge theory on a
spacetime lattice for constant value of the lattice spacing $a$ and for $N$
ranging from 3 to 8. The lattice spacing is fixed using the deconfinement
temperature at temporal extension of the lattice $N_T = 6$. The calculation is
conducted employing in each channel a variational ansatz performed on a large
basis of operators that includes also torelon and (for the lightest states)
scattering trial functions. This basis is constructed using an automatic
algorithm that allows us to build operators of any size and shape in any
irreducible representation of the cubic group. A good signal is extracted for
the ground state and the first excitation in several symmetry channels. It is
shown that all the observed states are well described by their large $N$
values, with modest ${\cal O}(1/N^2)$ corrections. In addition spurious states
are identified that couple to torelon and scattering operators. As a byproduct
of our calculation, the critical couplings for the deconfinement phase
transition for N=5 and N=7 and temporal extension of the lattice $N_T=6$ are
determined.Comment: 1+36 pages, 22 tables, 21 figures. Typos corrected, conclusions
  unchanged, matches the published versio
Pure-glue hidden valleys through the Higgs portal

We consider the possibility that the Higgs boson can act as a link to a
hidden sector in the context of pure-glue hidden valley models. In these models
the standard model is weakly coupled, through loops of heavy messengers fields,
to a hidden sector whose low energy dynamics is described by a pure-Yang-Mills
theory. Such a hidden sector contains several metastable hidden glueballs. In
this work we shall extend earlier results on hidden valleys to include
couplings of the messengers to the standard model Higgs sector. The effective
interactions at one-loop couple the hidden gluons to the standard model
particles through the Higgs sector. These couplings in turn induce hidden
glueball decays to fermion pairs, or cascade decays with multiple Higgs
emission. The presence of effective operators of different mass dimensions,
often competing with each other, together with a great diversity of states,
leads to a great variability in the lifetimes and decay modes of the hidden
glueballs. We find that most of the operators considered in this paper are not
heavily constrained by precision electroweak physics, therefore leaving plenty
of room in the parameter space to be explored by the future experiments at the
LHC.Comment: 44 pages, 16 figures. Major revision for JHEP, corrected an error in
  Eq. 5.1, comments adde
Pion and Vector Meson Form Factors in the Kuperstein-Sonnenschein
  holographic model

We study phenomenological aspects of the holographic model of chiral symmetry
breaking recently introduced by Kuperstein and Sonnenschein (KS). As a first
step, we calculate the spectrum of vector and axial-vector mesons in the KS
model. We numerically compute various coupling constants of the mesons and
pions. Our analysis indicates that vector meson dominance is realized in this
model. The pion, vector meson and axial-vector meson form factors are obtained
and studied in detail. We find good agreement with QCD results. In particular,
the pion form factor closely matches available experimental data.Comment: v1: 27 pages, 9 figures, 4 tables; v2: minor changes, added more
  general discussion of vector meson dominance; v3: minor changes and
  additions, version accepted for publication in JHE
Magnetic black holes with higher-order curvature and gauge corrections
  in even dimensions

We obtain magnetic black-hole solutions in arbitrary $n(\ge 4)$ even
dimensions for an action given by the Einstein-Gauss-Bonnet-Maxwell-$\Lambda$
pieces with the $F^4$ gauge-correction terms. This action arises in the low
energy limit of heterotic string theory with constant dilaton and vanishing
higher form fields. The spacetime is assumed to be a warped product ${\ma
M}^{2} \times {\ma K}^{n-2}$, where ${\ma K}^{n-2}$ is a $(n-2)$-dimensional
Einstein space satisfying a condition on its Weyl tensor, originally considered
by Dotti and Gleiser. Under a few reasonable assumptions, we establish the
generalized Jebsen-Birkhoff theorem for the magnetic solution in the case where
the orbit of the warp factor on ${\ma K}^{n-2}$ is non-null. We prove that such
magnetic solutions do not exist in odd dimensions. In contrast, in even
dimensions, we obtain an explicit solution in the case where ${\ma K}^{n-2}$ is
a product manifold of $(n-2)/2$ two-dimensional maximally symmetric spaces with
the same constant warp factors. In this latter case, we show that the global
structure of the spacetime sharply depends on the existence of the
gauge-correction terms as well as the number of spacetime dimensions.Comment: 22 pages, 4 figures; v2, typos corrected, references added, style
  changed, published version in JHE
CP properties of symmetry-constrained two-Higgs-doublet models

The two-Higgs-doublet model can be constrained by imposing Higgs-family
symmetries and/or generalized CP symmetries. It is known that there are only
six independent classes of such symmetry-constrained models. We study the CP
properties of all cases in the bilinear formalism. An exact symmetry implies CP
conservation. We show that soft breaking of the symmetry can lead to
spontaneous CP violation (CPV) in three of the classes.Comment: 14 pages, 2 tables, revised version adapted to the journal
  publicatio
Fake Superpotential for Large and Small Extremal Black Holes

We consider the fist order, gradient-flow, description of the scalar fields
coupled to spherically symmetric, asymptotically flat black holes in extended
supergravities. Using the identification of the fake superpotential with
Hamilton's characteristic function we clarify some of its general properties,
showing in particular (besides reviewing the issue of its duality invariance)
that W has the properties of a Liapunov's function, which implies that its
extrema (associated with the horizon of extremal black holes) are
asymptotically stable equilibrium points of the corresponding first order
dynamical system (in the sense of Liapunov). Moreover, we show that the fake
superpotential W has, along the entire radial flow, the same flat directions
which exist at the attractor point. This allows to study properties of the ADM
mass also for small black holes where in fact W has no critical points at
finite distance in moduli space. In particular the W function for small non-BPS
black holes can always be computed analytically, unlike for the large
black-hole case.Comment: 30 pages, LaTeX source. Discussion on the radial evolution of the
  scalar fields, in relation to the symmetries of the W-function, extended.
  Table 1 added. Typos correcte
Neutrino Masses from an A4 Symmetry in Holographic Composite Higgs
  Models

We show that holographic composite Higgs Models with a discrete A4 symmetry
naturally predict hierarchical charged lepton masses and an approximate
tri-bimaximal lepton mixing with the correct scale of neutrino masses. They
also satisfy current constraints from electroweak precision tests, lepton
flavor violation and lepton mixing in a large region of parameter space. Two
phenomenologically relevant features arise in these models. First, an extra
suppression on the lepton Yukawa couplings makes the tau lepton more composite
than naively expected from its mass. As a consequence new light leptonic
resonances, with masses as low as few hundreds of GeV, large couplings to tau
and a very characteristic collider phenomenology, are quite likely. Second, the
discrete symmetry A4 together with the model structure provide a double-layer
of flavor protection that allows to keep tree-level mediated processes below
present experimental limits. One-loop processes violating lepton flavor, like
mu -> e gamma, may be however observable at future experiments.Comment: 39 pages, 1 figur
An elementary stringy estimate of transport coefficients of large
  temperature QCD

Modeling QCD at large temperature with a simple holographic five dimensional
theory encoding minimal breaking of conformality, allows for the calculation of
all the transport coefficients, up to second order, in terms of a single
parameter. In particular, the shear and bulk relaxation times are provided. The
result follows by deforming the AdS background with a scalar dual to a
marginally relevant operator, at leading order in the deformation parameter.Comment: 11 pages; v2: comments and references adde
Beyond MFV in family symmetry theories of fermion masses

Minimal Flavour Violation (MFV) postulates that the only source of flavour
changing neutral currents and CP violation, as in the Standard Model, is the
CKM matrix. However it does not address the origin of fermion masses and mixing
and models that do usually have a structure that goes well beyond the MFV
framework. In this paper we compare the MFV predictions with those obtained in
models based on spontaneously broken (horizontal) family symmetries, both
Abelian and non-Abelian. The generic suppression of flavour changing processes
in these models turns out to be weaker than in the MFV hypothesis. Despite
this, in the supersymmetric case, the suppression may still be consistent with
a solution to the hierarchy problem, with masses of superpartners below 1 TeV.
A comparison of FCNC and CP violation in processes involving a variety of
different family quantum numbers should be able to distinguish between various
family symmetry models and models satisfying the MFV hypothesis.Comment: 34 pages, no figure
Leading-Order Determination of the Gluon Polarization from high-$p_T$
  Hadron Electroproduction

Longitudinal double-spin asymmetries of charged hadrons with high transverse
momentum $p_T$ have been measured in electroproduction using the \hermes\
detector at \hera. Processes involving gluons in the nucleon have been enhanced
relative to others by selecting hadrons with $p_T$ typically above 1 GeV. In
this kinematic domain the gluon polarization has been extracted in leading
order making use of the model embedded in the Monte Carlo Generator \Pythia\
6.2. The gluon polarization obtained from single inclusive hadrons in the $p_T$
range 1 GeV $< p_T <$ 2.5 GeV using a deuterium target is $\frac{\Delta
g}{g}(\langle x\rangle, \langle \mu^2\rangle)=0.049\pm 0.034 (stat)\pm 0.010
(sys\textrm{-}exp)^{+0.126}_{-0.099}(sys\textrm{-}models)$ at a scale
$\la\mu^2\ra=1.35~{\rm GeV}^2$ and $\langle x\rangle = 0.22$. For different
final states and kinematic domains, consistent values of \DGG\ have been found
within statistical uncertainties using hydrogen and deuterium targets
5 loops in 24/5 dimensions

A first quantised approach to loop amplitudes based on the pure spinor
particle is applied to the systematics of four-particle amplitudes in maximally
supersymmetric field theories. Counting of fermionic zero modes allows the
identification of momentum factors multiplying R**4 in the case of supergravity
(and F**4 in the Yang--Mills case) thereby making manifest their ultraviolet
properties as a function of dimension, D. For L=2,3,4 loops the leading
supergravity divergence is in D=4+6/L dimensions and proportional to d*2L R**4,
in line with earlier field theory calculations. However, at five loops there is
a radical change in the systematics, suggesting the presence of a contribution
with an explicit L=5 logarithmic ultraviolet divergence when D=24/5 that is
proportional to d*8 R**4. We further argue that d*8 R**4 should receive
contributions from all loops, which would imply that N=8 supergravity (with
D=4) is not protected by supersymmetry from a seven-loop divergence.Comment: 23 pages, 7 figures. Version published in journa