pinecone/core-2020-05-10-deduplication huggingface dataset:
The covariant, time-dependent Aharonov-Bohm Effect

We discuss two possible covariant generalizations of the Aharonov-Bohm effect
- one expression in terms of the space-time line integral of the four-vector
potential and the other expression in terms of the space-time "area" integral
of the electric and magnetic fields written in terms of the Faraday 2-form.
These expressions allow one to calculate the Aharonov-Bohm effect for
time-dependent situations. In particular, we use these expressions to study the
case of an infinite solenoid with a time varying flux and find that the phase
shift is zero due to a cancellation of the Aharonov-Bohm phase shift with a
phase shift coming from the Lorentz force associated with the electric field,
${\bf E} = - \partial_t {\bf A}$, outside the solenoid. This result may already
have been confirmed experimentally.Comment: 11 pages, no figures, journal version, three added reference
Quasars Probing Quasars VI. Excess HI Absorption Within One Proper Mpc
  of z~2 Quasars

With close pairs of quasars at different redshifts, a background quasar
sightline can be used to study a foreground quasar's environment in absorption.
We use a sample of 650 projected quasar pairs to study the HI Lya absorption
transverse to luminous, z~2 quasars at proper separations of 30kpc < R < 1Mpc.
In contrast to measurements along the line-of-sight, regions transverse to
quasars exhibit enhanced HI Lya absorption and a larger variance than the
ambient intergalactic medium, with increasing absorption and variance toward
smaller scales. Analysis of composite spectra reveals excess absorption
characterized by a Lya equivalent width profile W = 2.3A (R/100kpc)^-0.46. We
also observe a high (~60%) covering factor of strong, optically thick HI
absorbers (HI column log NHI > 17.3) at separations R<200kpc, which decreases
to ~20% at R~1Mpc, but still represents a significant excess over the cosmic
average. This excess of optically thick absorption can be described by a
quasar-absorber cross-correlation function xi_QA(r) = (r/r_0)^gamma with a
large correlation length r_0 = 12.5+2.7-1.4 Mpc/h (comoving) and gamma =
1.68+0.14-0.30. The HI absorption measured around quasars exceeds that of any
previously studied population, consistent with quasars being hosted by massive
dark matter halos Mhalo~10^12.5 Msun at z~2.5. The environments of these
massive halos are highly biased towards producing optically thick gas, and may
even dominate the cosmic abundance of Lyman limit systems and hence the
intergalactic opacity to ionizing photons at z~2.5. The anisotropic absorption
around quasars implies the transverse direction is much less likely to be
illuminated by ionizing radiation than the line-of-sight, which we interpret in
terms of the same obscuration effects frequently invoked in unified models of
active galactic nuclei.Comment: Accepted to ApJ; 38 pages, 25 figures. Comments still welcom
Precise Higgs-background predictions: merging NLO QCD and squared
  quark-loop corrections to four-lepton + 0,1 jet production

We present precise predictions for four-lepton plus jets production at the
LHC obtained within the fully automated Sherpa+OpenLoops framework. Off-shell
intermediate vector bosons and related interferences are consistently included
using the complex-mass scheme. Four-lepton plus 0- and 1-jet final states are
described at NLO accuracy, and the precision of the simulation is further
increased by squared quark-loop NNLO contributions in the gg -> 4l, gg -> 4l+g,
gq -> 4l+q, and qq -> 4l+g channels. These NLO and NNLO contributions are
matched to the Sherpa parton shower, and the 0- and 1-jet final states are
consistently merged using the MEPS@NLO technique. Thanks to Sudakov
resummation, the parton shower provides improved predictions and uncertainty
estimates for exclusive observables. This is important when jet vetoes or jet
bins are used to separate four-lepton final states arising from Higgs decays,
diboson production, and top-pair production. Detailed predictions are presented
for the ATLAS and CMS H->WW analyses at 8 TeV in the 0- and 1-jet bins.
Assessing renormalisation-, factorisation- and resummation-scale uncertainties,
which reflect also unknown subleading Sudakov logarithms in jet bins, we find
that residual perturbative uncertainties are as small as a few percent.Comment: 44 pages, 13 figures, 7 tables. v2: More detailed discussion of
  merging-scale dependence in Sect. 3.3 and detailed assessment of
  merging-scale uncertainties in Sect.5.3.; to appear in JHE
VIMOS Ultra-Deep Survey (VUDS): Witnessing the Assembly of a Massive
  Cluster at z~3.3

Using new spectroscopic observations obtained as part of the VIMOS Ultra-Deep
Survey (VUDS), we perform a systematic search for overdense environments in the
early universe ($z>2$) and report here on the discovery of Cl J0227-0421, a
massive protocluster at $z=3.29$. This protocluster is characterized by both
the large overdensity of spectroscopically confirmed members,
$\delta_{gal}=10.5\pm2.8$, and a significant overdensity in photometric
redshift members. The halo mass of this protocluster is estimated, by a variety
of methods, to be roughly $3\times10^{14}$ $\mathcal{M}_{\odot}$ at $z\sim3.3$,
which, evolved to $z=0$ results in a halo mass rivaling or exceeding that of
the Coma cluster. The properties of 19 spectroscopically confirmed member
galaxies are compared with a large sample of VUDS/VVDS galaxies in lower
density field environments at similar redshifts. We find tentative evidence for
an excess of redder, brighter, and more massive galaxies within the confines of
the protocluster relative to the field population, which suggests that we may
be observing the beginning of environmentally-induced quenching. The properties
of these galaxies are investigated, including a discussion of the brightest
protocluster galaxy which appears to be undergoing vigorous coeval nuclear and
starburst activity. The remaining member galaxies appear to have
characteristics which are largely similar to the field population. Though we
find weaker evidence of the suppression of the median star formation rates
amongst and differences in stacked spectra of member galaxies with respect to
the field, we defer any conclusions of these trends to future work with the
ensemble of protostructures that are found in the full VUDS sample.Comment: 23 pages, 15 figures, 3 tables, accepted for publication in A&A after
  minor changes, v3/v4 contains an additional online table and minor topical
  change
Remarks on higher-order hadronic corrections to the muon g-2

Recently, it was shown that insertions of hadronic vacuum polarization at
O(alpha^4) generate non-negligible effects in the calculation of the anomalous
magnetic moment of the muon. This result raises the question if other hadronic
diagrams at this order might become relevant for the next round of g-2
measurements as well. In this note we show that a potentially enhanced such
contribution, hadronic light-by-light scattering in combination with electron
vacuum polarization, is already sufficiently suppressed.Comment: 2 pages, 1 figure; journal versio
N=4 Scattering Amplitudes and the Deformed Grassmannian

Some time ago the general tree-level scattering amplitudes of N=4 Super
Yang-Mills theory were expressed as certain Grassmannian contour integrals.
These remarkable formulas allow to clearly expose the super-conformal, dual
super-conformal, and Yangian symmetries of the amplitudes. Using ideas from
integrability it was recently shown that the building blocks of the amplitudes
permit a natural multi-parameter deformation. However, this approach had been
criticized by the observation that it seemed impossible to reassemble the
building blocks into Yangian-invariant deformed non-MHV amplitudes. In this
note we demonstrate that the deformations may be succinctly summarized by a
simple modification of the measure of the Grassmannian integrals, leading to a
Yangian-invariant deformation of the general tree-level amplitudes.
Interestingly, the deformed building-blocks appear as residues of poles in the
spectral parameter planes. Given that the contour integrals also contain
information on the amplitudes at loop-level, we expect the deformations to be
useful there as well. In particular, applying meromorphicity arguments, they
may be expected to regulate all notorious infrared divergences. We also point
out relations to Gelfand hypergeometric functions and the quantum
Knizhnik-Zamolodchikov equations.Comment: 15 page
CLASH-VLT: The stellar mass function and stellar mass density profile of
  the z=0.44 cluster of galaxies MACS J1206.2-0847

Context. The study of the galaxy stellar mass function (SMF) in relation to
the galaxy environment and the stellar mass density profile, rho(r), is a
powerful tool to constrain models of galaxy evolution. Aims. We determine the
SMF of the z=0.44 cluster of galaxies MACS J1206.2-0847 separately for passive
and star-forming (SF) galaxies, in different regions of the cluster, from the
center out to approximately 2 virial radii. We also determine rho(r) to compare
it to the number density and total mass density profiles. Methods. We use the
dataset from the CLASH-VLT survey. Stellar masses are obtained by SED fitting
on 5-band photometric data obtained at the Subaru telescope. We identify 1363
cluster members down to a stellar mass of 10^9.5 Msolar. Results. The whole
cluster SMF is well fitted by a double Schechter function. The SMFs of cluster
SF and passive galaxies are statistically different. The SMF of the SF cluster
galaxies does not depend on the environment. The SMF of the passive population
has a significantly smaller slope (in absolute value) in the innermost (<0.50
Mpc), highest density cluster region, than in more external, lower density
regions. The number ratio of giant/subgiant galaxies is maximum in this
innermost region and minimum in the adjacent region, but then gently increases
again toward the cluster outskirts. This is also reflected in a decreasing
radial trend of the average stellar mass per cluster galaxy. On the other hand,
the stellar mass fraction, i.e., the ratio of stellar to total cluster mass,
does not show any significant radial trend. Conclusions. Our results appear
consistent with a scenario in which SF galaxies evolve into passive galaxies
due to density-dependent environmental processes, and eventually get destroyed
very near the cluster center to become part of a diffuse intracluster medium.Comment: A&A accepted, 15 pages, 13 figure
Evolution of the dust emission of massive galaxies up to z=4 and
  constraints on their dominant mode of star formation

We aim to measure the average dust and molecular gas content of massive
star-forming galaxies ($\rm > 3 \times 10^{10}\,M_\odot$) up to z=4 in the
COSMOS field to determine if the intense star formation observed at high
redshift is induced by major mergers or caused by large gas reservoirs.
Firstly, we measured the evolution of the average spectral energy distributions
as a function of redshift using a stacking analysis of Spitzer, Herschel,
LABOCA, and AzTEC data for two samples of galaxies: normal star-forming objects
and strong starbursts, as defined by their distance to the main sequence. We
found that the mean intensity of the radiation field $< U >$ heating the dust
(strongly correlated with dust temperature) increases with increasing redshift
up to z$\sim$4 in main-sequence galaxies. We can reproduce this evolution with
simple models that account for the decrease of the gas metallicity with
redshift. No evolution of $< U >$ with redshift is found in strong starbursts.
We then deduced the evolution of the molecular gas fraction (defined here as
$\rm M_{\rm mol}/(M_{\rm mol}+M_\star)$) with redshift and found a similar,
steeply increasing trend for both samples. At z$\sim$4, this fraction reaches
$\sim$60%. The average position of the main-sequence galaxies is on the locus
of the local, normal star-forming disks in the integrated Schmidt-Kennicutt
diagram (star formation rate versus mass of molecular gas), suggesting that the
bulk of the star formation up to z=4 is dominated by secular processes.Comment: 17 pages, 14 figures, 2 tables, accepted by A&
Compromise of Localized Graviton with a Small Cosmological Constant in
  Randall-Sundrum Scenario

A new mechanism which leads to a linearized massless graviton localized on
the brane is found in the $AdS$/CFT setting, {\it i.e.} in a single copy of
$AdS_5$ spacetime with a singular brane on the boundary, within the
Randall-Sundrum brane-world scenario. With an help of a recent development in
path-integral techniques, a one-parameter family of propagators for linearized
gravity is obtained analytically, in which a parameter $\xi$ reflects various
kinds of boundary conditions that arise as a result of the half-line
constraint. In the case of a Dirichlet boundary condition ($\xi = 0$) the
graviton localized on the brane can be massless {\it via} coupling constant
renormalization. Our result supports a conjecture that the usual
Randall-Sundrum scenario is a regularized version of a certain underlying
theory.Comment: 6 pages, no figure, V2 12 pages, one more author added, will appear
  in PL
Scaling of particle production with number of participants in high-energy A + A collisions in the parton-cascade model

In view of the recent WA98 data of $\pi^0$ spectra from central Pb+Pb collisions at the CERN SPS, we analyze the production of neutral pions for A+A collisions across the periodic table at $\sqrt{s}=17$ AGeV and 200 AGeV within the framework of the parton-cascade model for relativistic heavy ion collisions. The multiplicity of the pions (having $p_T > 0.5$ GeV) in the central rapidity region, is seen to scale as $\sim (N_{part})^{\alpha}$, where $N_{part}$ is the number of participating nucleons, which we have approximated as 2A for central collisions of identical nuclei. We argue that the deviation of $\alpha$ ($\simeq 1.2$) from unity may have its origin in the multiple scattering suffered by the partons. We also find that the constant of proportionality in the above scaling relation increases substantially in going from SPS to RHIC energies. This would imply that the (semi)hard partonic activity becomes a much cleaner signal above the soft particle production at the higher energy of RHIC, and thus much less dependent on the (lack of) understanding of the underlying soft physics background
The variational principle for dust shells

Variational principles for thin dust shells are considered in Newtonian theory of gravity, and for charged shells in Special Relativity. We propose the variational principle for thin massive dust shells in General Relativity and study the results following from it. The configuration, being considered, can be thought of as the two vacuum regions with the dust shell as the boundary surface between them. The full action of the system we take as the sum of actions in the form of the York-Gibbons-Hawking type for both regions and of the boundary term containing the action of the dust matter and of the corresponding matching surface term. The variational principle is compatible with the boundary-value problem of the Euler-Lagrange equations for either regions of the configuration, and leads to "natural boundary conditions" on the shell. These conditions can be considered as the constraints, and, together with the gravitational field equations, are used for elimination of the gravitational degrees of freedom. The full reduction of the action are performed here for spherically-symmetric systems. By transforming the variational formula it is shown that the obtained action with constraints is equivalent to the two variants of the effective action without constraints for a particle with self-action moving in the external gravitational field. One of these variants describes the shell from the interior resting observer's point of view, another from the exterior one. The conditions of isometry of the exterior and interior sides of the shell lead to the Hamiltonian constraints
Supersymmetric Scaling Violations (I). An Algorithm to Solve the Supersymmetric DGLAP Evolution

We discuss a method for the numerical solution of the renormalization group equations of supersymmetric QCD with N=1 for the evolution of parton distributions. After a discussion of the original algorithm in which we show its connection to other finite-step expansions, such as the Furmanski-Petronzio (FP) expansion, we extend it to include both regular regions and supersymmetric regions in the evolution. Here we focus on a scenario with broken susy, characterized by a lighter gluino coupled to the standard evolution and a decoupled scalar quark. The formulation of the method is illustrated to next to leading order, with approximate matching conditions at the gluino threshold mass. A leading order implementation is presented. Modifications on the standard evolution are shown to be small down to $x=10^{-2}$ both for gluinos and for the distributions of quarks and gluons
Towards the lattice study of M-theory, 2

We present new results of the quenched simulations of the reduced D=4 supersymmetric Yang - Mills quantum mechanics for larger gauge groups SU(N), 2<N<9. The model, studied at finite temperature, reveals existence of the two distinct regions which may be precursors of a black hole and the elementary D0 branes phases of M-theory conjectured in the literature. Present results for higher groups confirm the picture found already for N=2. Similar behaviour is observed in the preliminary simulations for the D=6 and D=10 models
A type-Rainich approach to the Killing-Yano tensors

Following an approach by Collinson we solve the Rainich problem for the Killing-Yano tensors: firstly we give the necessary and sufficient conditions for a 2+2 almost-product structure to determine the principal 2--planes of a skew-symmetric Killing-Yano tensor and, secondly, we obtain the additional conditions on a symmetric Killing tensor for it to be the square of a Killing-Yano tensor. We also analyze a similar problem for the conformal Killing-Yano and the conformal Killing tensors. Our results show that, in both cases, the principal 2--planes define a maxwellian structure. The associated Maxwell fields are obtained and we outline how this approach is of interest in studying the spacetimes that admit these kind of first integrals of the geodesic equation
The Vacuum Functional at Large Distances

For fields that vary slowly on the scale of the lightest mass the logarithm
of the vacuum functional can be expanded as a sum of local functionals, however
this does not satisfy the obvious form of the Schr\"odinger equation. For
$\varphi^4$ theory we construct the appropriate equation that this expansion
does satisfy. This reduces the eigenvalue problem for the Hamiltonian to a set
of algebraic equations. We suggest two approaches to their solution. The first
is equivalent to the usual semi-classical expansion whilst the other is a new
scheme that may also be applied to theories that are classically massless but
in which mass is generated quantum mechanically.Comment: 11 pages, late
Non linear integral equation and excited--states scaling functions in
  the sine-Gordon model

The NLIE (the non-linear integral equation equivalent to the Bethe Ansatz
equations for finite size) is generalized to excited states, that is states
with holes and complex roots over the antiferromagnetic ground state. We
consider the sine-Gordon/massive Thirring model (sG/mT) in a periodic box of
length $L$ using the light-cone approach, in which the sG/mT model is obtained
as the continuum limit of an inhomogeneous six vertex model. This NLIE is an
useful starting point to compute the spectrum of excited states both
analytically in the large $L$ (perturbative) and small $L$ (conformal) regimes
as well as numerically.Comment: LaTeX file, 40 pages, 4 figures in a tar.Z file (3 figures added and
  few misprints corrected w.r.t. previous version
Improving DISPGB Algorithm Using the Discriminant Ideal

In 1992, V. Weispfenning proved the existence of Comprehensive Groebner Bases
(CGB) and gave an algorithm to compute one. That algorithm was not very
efficient and not canonical. Using his suggestions, A. Montes obtained in 2002
a more efficient algorithm (DISPGB) for Discussing Parametric Groebner Bases.
Inspired in its philosophy, V. Weispfenning defined, in 2002, how to obtain a
Canonical Comprehensive Groebner Basis (CCGB) for parametric polynomial ideals,
and provided a constructive method.
  In this paper we use Weispfenning's CCGB ideas to make substantial
improvements on Montes DISPGB algorithm. It now includes rewriting of the
discussion tree using the Discriminant Ideal and provides a compact and
effective discussion. We also describe the new algorithms in the DPGB library
containing the improved DISPGB as well as new routines to check whether a given
basis is a CGB or not, and to obtain a CGB. Examples and tests are also
provided.Comment: 21 pages, see also http://www-ma2.upc.edu/~montes
Three-body dN interaction in the analysis of the 12C(pol_d,d') reaction
  at 270 MeV

We have measured the cross sections and analyzing powers Ay and Ayy for the
elastic and inelastic scattering of deuterons from the 0+(g.s.), 2+(4.44 MeV),
3-(9.64 MeV), 1+(12.71 MeV), and 2-(18.3 MeV) states in 12C at an incident
energy of 270 MeV. The data are compared with microscopic distorted-wave
impulse approximation calculations where the projectile-nucleon effective
interactionis taken from the three-nucleon t-matrix given by rigorous Faddeev
calculations presently available at intermediate energies. The agreement
between theory and data compares well with that for the (p,p') reactions at
comparable incident energies/nucleon.Comment: 17 pages, 3 Postscript figure
A New Coupling Potential for the Scattering of Deformed Light Heavy-Ions

This letter introduces a new coupling potential to explain the experimental
data over wide energy ranges for a number of systems. Within the
coupled-channels formalism, this letter first shows the limitations of the
standard coupled-channels theory in the case where one of the nuclei in the
reaction is strongly deformed and then, demonstrates that a global solution to
the problems of light heavy-ion reactions such as $^{12}$C+$^{12}$C,
$^{16}$O+$^{28}$Si and $^{12}$C+$^{24}$Mg can be found using a new
second-derivative coupling potential in the coupled-channels formalism. This
new approach consistently improves the agreement with the experimental data for
the elastic and inelastic scattering data as well as for their excitation
functions using constant or slightly energy-dependent parameters.Comment: 4 Pages, 5 Figures, submitted to the Phys. Lett.
Bifurcation in kinetic equation for interacting Fermi systems

The finite duration of collisions appear as time-nonlocality in the kinetic
equation. Analyzing the corresponding quantum kinetic equation for dense
interacting Fermi systems a delay differential equation is obtained which
combines time derivatives with finite time stepping known from the logistic
mapping. The responsible delay time is explicitly calculated and discussed. As
a novel feature oscillations in the time evolution of the distribution function
itself appear and bifurcations up to chaotic behavior can occur. The
temperature and density conditions are presented where such oscillations and
bifurcations arise indicating an onset of phase transition