pinecone/core-2020-05-10-deduplication huggingface dataset:
Pentagon functions for massless planar scattering amplitudes.

Loop amplitudes for massless five particle scattering processes contain Feynman integrals depending on the external momentum invariants: pentagon functions. We perform a detailed study of the analyticity properties and cut structure of these functions up to two loops in the planar case, where we classify and identify the minimal set of basis functions. They are computed from the canonical form of their differential equations and expressed in terms of generalized polylogarithms, or alternatively as one-dimensional integrals. We present analytical expressions and numerical evaluation routines for these pentagon functions, in all kinematical configurations relevant to five-particle scattering processes
Solving and classifying the solutions of the Yang-Baxter equation
  through a differential approach. Two-state systems

The formal derivatives of the Yang-Baxter equation with respect to its
spectral parameters, evaluated at some fixed point of these parameters, provide
us with two systems of differential equations. The derivatives of the $R$
matrix elements, however, can be regarded as independent variables and
eliminated from the systems, after which two systems of polynomial equations
are obtained in place. In general, these polynomial systems have a non-zero
Hilbert dimension, which means that not all elements of the $R$ matrix can be
fixed through them. Nonetheless, the remaining unknowns can be found by solving
a few number of simple differential equations that arise as consistency
conditions of the method. The branches of the solutions can also be easily
analyzed by this method, which ensures the uniqueness and generality of the
solutions. In this work we considered the Yang-Baxter equation for two-state
systems, up to the eight-vertex model. This differential approach allowed us to
solve the Yang-Baxter equation in a systematic way and also to completely
classify its regular solutions.Comment: Final version. 40 pages, 3 tables. Keywords: Yang-Baxter Equation,
  Lattice Integrable Models, Eight-Vertex Model, Bethe Ansatz, Differential and
  Algebraic Geometr
Localized $4\sigma$ and $5\sigma$ Dijet Mass Excesses in ALEPH LEP2
  Four-Jet Events

We investigate an excess observed in hadronic events in the archived LEP2
ALEPH data. This excess was observed at preselection level during data-MC
comparisons of four-jet events when no search was being performed. The events
are clustered into four jets and paired such that the mass difference between
the two dijet systems is minimized. The excess occurs in the region
$M_1+M_2\sim 110\mbox{ GeV}$; about half of the excess is concentrated in the
region $M_1\sim 80\mbox{ GeV}$, $M_2\sim 25\mbox{ GeV}$, with a local
significance between $4.7\sigma$ and $5.5\sigma$, depending on assumptions
about hadronization uncertainties. The other half of the events are in a broad
excess near $M_1\sim M_2\sim 55\mbox{ GeV}$; these display a local significance
of $4.1-4.5\sigma$. We investigate the effects of changing the SM QCD Monte
Carlo sample, the jet-clustering algorithm, and the jet rescaling method. We
find that the excess is remarkably robust under these changes, and we find no
source of systematic uncertainty that can explain the excess. No analogue of
the excess is seen at LEP1.Comment: 40 pages, 17 figures. Version published in JHEP. Detector section
  removed, S/B and SM expectation figure added, expanded discussion of
  hadronization uncertainties, small changes in systematic errors due to LEP1
  data statistics, table added with significance as a function of
  center-of-mass energy, changes in tex
Freezing In, Heating Up, and Freezing Out: Predictive Nonthermal Dark
  Matter and Low-Mass Direct Detection

Freeze-in dark matter (DM) mediated by a light ($\ll$ keV) weakly-coupled
dark-photon is an important benchmark for the emerging low-mass direct
detection program. Since this is one of the only predictive, detectable
freeze-in models, we investigate how robustly such testability extends to other
scenarios. For concreteness, we perform a detailed study of models in which DM
couples to a light scalar mediator and acquires a freeze-in abundance through
Higgs-mediator mixing. Unlike dark-photons, whose thermal properties weaken
stellar cooling bounds, the scalar coupling to Standard Model (SM) particles is
subject to strong astrophysical constraints, which severely limit the fraction
of DM that can be produced via freeze-in. While it seems naively possible to
compensate for this reduction by increasing the mediator-DM coupling,
sufficiently large values eventually thermalize the dark sector with itself and
yield efficient DM annihilation to mediators, which depletes the freeze-in
population; only a small window of DM candidate masses near the $\sim$ GeV
scale can accommodate the total observed abundance. Since many qualitatively
similar issues arise for other light mediators, we find it generically
difficult to realize a viable freeze-in scenario in which production arises
only from renormalizable interactions with SM particles. We also comment on
several model variations that may evade these conclusions.Comment: 19 pages, 5 figures, 2 appendice
The twistor Wilson loop and the amplituhedron.

The amplituhedron provides a beautiful description of perturbative superamplitude\ud
integrands in N = 4 SYM in terms of purely geometric objects, generalisations of\ud
polytopes. On the other hand the Wilson loop in supertwistor space also gives an explicit\ud
description of these superamplitudes as a sum of planar Feynman diagrams. Each Feynman\ud
diagram can be naturally associated with a geometrical object in the same space as the\ud
amplituhedron (although not uniquely). This suggests that these geometric images of the\ud
Feynman diagrams give a tessellation of the amplituhedron. This turns out to be the case\ud
for NMHV amplitudes. We argue however that beyond NMHV this is not true. Specifically,\ud
each Feynman diagram leads to an image with a physical boundary and spurious\ud
boundaries. The spurious ones should be “internal”, matching with neighbouring diagrams.\ud
We however show that there is no choice of geometric image of the Wilson loop Feynman\ud
diagrams which yields a geometric object without leaving unmatched spurious boundaries
Infrared sensitivity of single jet inclusive production at hadron colliders.

Jet production at hadron colliders is a benchmark process to probe the dynamics of the strong interaction and the structure of the colliding hadrons. One of the most basic jet production observables is the single jet inclusive cross section, which is obtained by summing all jets that are observed in an event. Our recent computation of next-to-next-to-leading order (NNLO) QCD contributions to single jet inclusive observables uncovered large corrections in certain kinematical regions, which also resulted in a sizeable ambiguity on the appropriate choice of renormalization and factorization scales. We now perform a detailed investigation of the infrared sensitivity of the different ingredients to the single jet inclusive cross section. We show that the contribution from the second jet, ordered in transverse momentum pT, in the event is particularly sensitive to higher order effects due to implicit restrictions on its kinematics. By investigating the second-jet transverse momentum distribution, we identify large-scale cancellations between different kinematical event configurations, which are aggravated by certain types of scale choice. Taking perturbative convergence and stability as selection criteria enables us to single out the total partonic transverse energy ĤT and twice the individual jet transverse momentum 2 pT (with which ĤT coincides in Born kinematics) as the most appropriate scales in the perturbative description of single jet inclusive production
Hard photons in hadroproduction of top quarks with realistic final states.

We present a complete description of top quark pair production in association with a hard photon in the dilepton channel. Our calculation is accurate to NLO in QCD. It is based on matrix elements for   e+νeμ−ν¯¯¯μbb¯¯γ  production and includes all resonant and non-resonant diagrams, interferences, and off-shell effects of the top quarks and the W gauge bosons. This calculation constitutes the first full computation for top quark pair production with a final state photon in hadronic collisions at NLO in QCD. Numerical results for total and differential cross sections are presented for the LHC at a centre-of-mass energy of   s√=13  TeV. For a few observables relevant for new physics searches, beyond some kinematic bounds, we observe shape distortions of more than 100%. In addition, we confirm that the size of the top quark off-shell effects for the total cross section is consistent with the expected uncertainties of the narrow width approximation. Results presented here are not only relevant for beyond the Standard Model physics searches but also important for precise measurements of the top-quark fiducial cross sections and top-quark properties at the LHC
Measurements of differential cross sections of top quark pair production in association with jets in pp collisions at s√=13 TeV using the ATLAS detector

Measurements of differential cross sections of top quark pair production in association with jets by the ATLAS experiment at the LHC are presented. The measurements are performed as functions of the top quark transverse momentum, the transverse momentum of the top quark-antitop quark system and the out-of-plane transverse momentum using data from pp collisions at s√=13 TeV collected by the ATLAS detector at the LHC in 2015 and corresponding to an integrated luminosity of 3.2 fb−1. The top quark pair events are selected in the lepton (electron or muon) + jets channel. The measured cross sections, which are compared to several predictions, allow a detailed study of top quark production
Relating 't Hooft Anomalies of 4d Pure Yang-Mills and 2d
  $\mathbb{CP}^{N-1}$ Model

It has recently been shown that a center-twisted compactification of the
four-dimensional pure $SU(N)$ Yang-Mills theory on a three-torus gives rise to
the two-dimensional $\mathbb{CP}^{N-1}$-model on a circle with a flavor-twisted
boundary condition. We verify the consistency of this statement
non-perturbatively at theta angle $\theta=\pi$, in terms of the mixed 't Hooft
anomalies for flavor symmetries and the time-reversal symmetry. This provides
further support for the approach to the confinement of four-dimensional
Yang-Mills theory from the two-dimensional $\mathbb{CP}^{N-1}$-model.Comment: 6 page
The low-energy limit of AdS3/CFT2 and its TBA

We investigate low-energy string excitations in AdS3 × S\ud
3 × T\ud
4\ud
. When the worldsheet is decompactified,\ud
the theory has gapless modes whose spectrum at low energies is determined by massless\ud
relativistic integrable S matrices of the type introduced by Al. B. Zamolodchikov. The S matrices\ud
are non-trivial only for excitations with identical worldsheet chirality, indicating that the low-energy\ud
theory is a CFT2. We construct a Thermodynamic Bethe Ansatz (TBA) for these excitations and\ud
show how the massless modes’ wrapping effects may be incorporated into the AdS3 spectral problem.\ud
Using the TBA and its associated Y-system, we determine the central charge of the low-energy CFT2\ud
to be c = 6 from calculating the vacuum energy for antiperiodic fermions - with the vacuum energy\ud
being zero for periodic fermions in agreement with a supersymmetric theory - and find the energies\ud
of some excited states
Search for dark matter in events with a hadronically decaying vector boson and missing transverse momentum in pp collisions at s√=13 TeV with the ATLAS detector

A search for dark matter (DM) particles produced in association with a hadronically decaying vector boson is performed using pp collision data at a centre-of-mass energy of s√=13 TeV corresponding to an integrated luminosity of 36.1 fb−1, recorded by the ATLAS detector at the Large Hadron Collider. This analysis improves on previous searches for processes with hadronic decays of W and Z bosons in association with large missing transverse momentum (mono-W/Z searches) due to the larger dataset and further optimization of the event selection and signal region definitions. In addition to the mono-W/Z search, the as yet unexplored hypothesis of a new vector boson Z′ produced in association with dark matter is considered (mono-Z′ search). No significant excess over the Standard Model prediction is observed. The results of the mono-W/Z search are interpreted in terms of limits on invisible Higgs boson decays into dark matter particles, constraints on the parameter space of the simplified vector-mediator model and generic upper limits on the visible cross sections for W/Z+DM production. The results of the mono-Z′ search are shown in the framework of several simplified-model scenarios involving DM production in association with the Z′ boson
Blowup Equations for Refined Topological Strings

G\"{o}ttsche-Nakajima-Yoshioka K-theoretic blowup equations characterize the
Nekrasov partition function of five dimensional $\mathcal{N}=1$ supersymmetric
gauge theories compactified on a circle, which via geometric engineering
correspond to the refined topological string theory on $SU(N)$ geometries. In
this paper, we study the K-theoretic blowup equations for general local
Calabi-Yau threefolds. We find that both vanishing and unity blowup equations
exist for the partition function of refined topological string, and the crucial
ingredients are the $\bf r$ fields introduced in our previous paper. These
blowup equations are in fact the functional equations for the partition
function and each of them results in infinite identities among the refined free
energies. Evidences show that they can be used to determine the full refined
BPS invariants of local Calabi-Yau threefolds. This serves an independent and
sometimes more powerful way to compute the partition function other than the
refined topological vertex in the A-model and the refined holomorphic anomaly
equations in the B-model. We study the modular properties of the blowup
equations and provide a procedure to determine all the vanishing and unity $\bf
r$ fields from the polynomial part of refined topological string at large
radius point. We also find that certain form of blowup equations exist at
generic loci of the moduli space.Comment: 85 pages. v2: Journal versio
Low-scale warped extra dimension and its predilection for multiple top
  quarks

Within warped extra dimension models that explain flavor through geometry,
flavor changing neutral current constraints generally force the Kaluza-Klein
scale to be above many TeV. This creates tension with a natural electroweak
scale. On the other hand, a much lower scale compatible with precision
electroweak and flavor changing neutral current constraints is allowed if we
decouple the Kaluza-Klein states of Standard Model gauge bosons from light
fermions $c_{\rm light}\simeq c_b\simeq 0.5$ bulk mass parameters). The main
signature for this approach is four top quark production via the Kaluza-Klein
excitations' strong coupling to top quarks. We study single lepton, like-sign
dilepton, and trilepton observables of four-top events at the Large Hadron
Collider. The like-sign dilepton signature typically has the largest discovery
potential for a strongly coupled right-handed top case ($M_{KK} \sim 2-2.5
\TeV$), while single lepton is the better when the left-handed top couples most
strongly ($M_{KK} \sim 2 \TeV$). We also describe challenging lepton-jet
collimation issues in the like-sign dilepton and trilepton channels. An
alternative single lepton observable is considered which takes advantage of the
many bottom quarks in the final state. Although searches of other particles may
compete, we find that four top production via Kaluza-Klein gluons is most
promising in a large region of this parameter space.Comment: 35 pages, 8 figures. discussions improved, references adde
Hidden conformal symmetry of extreme and non-extreme
  Einstein-Maxwell-Dilaton-Axion black holes

The hidden conformal symmetry of extreme and non-extreme
Einstein-Maxwell-Dilaton-Axion (EMDA) black holes is addressed in this paper.
For the non-extreme one, employing the wave equation of massless scalars, the
conformal symmetry with left temperature $T_{L}=\frac{M}{2\pi a}$ and right
temperature $T_{R}=\frac{\sqrt{M^{2}-a^{2}}}{2\pi a}$ in the near region is
found. The conformal symmetry is spontaneously broken due to the periodicity of
the azimuthal angle. The microscopic entropy is derived by the Cardy formula
and is fully in consistence with the Bekenstein-Hawking area-entropy law. The
absorption cross section in the near region is calculated and exactly equals
that in a 2D CFT. For the extreme case, by redefining the conformal
coordinates, the duality between the solution space and CFT is studied. The
microscopic entropy is found to exactly agree with the area-entropy law.Comment: V3, typos corrected, version to appear in JHE
Probing High Reheating Temperature Scenarios at the LHC with Long-Lived
  Staus

We investigate the possibility of probing high reheating temperature
scenarios at the LHC, in supersymmetric models where the gravitino is the
lightest supersymmetric particle, and the stau is the next-to-lightest
supersymmetric particle. In such scenarios, the big-bang nucleosynthesis and
the gravitino abundance give a severe upper bound on the gluino mass. We find
that, if the reheating temperature is \sim 10^8 GeV or higher, the scenarios
can be tested at the LHC with an integrated luminosity of O(1 fb^{-1}) at
\sqrt{s}=7 TeV in most of the parameter space.Comment: 17 pages, 5 figures, minor modification
Leptonic signatures of doubly charged Higgs boson production at the LHC

The production of doubly charged Higgs bosons (H^{\pm\pm}) at the CERN LHC
can give rise to distinctive multi-lepton signatures. The discovery potential
of H^{\pm\pm} can be optimized by considering a search strategy which is
sensitive to both of the dominant production mechanisms, q\bar q\to
H^{++}H^{--} and q\bar {q'}\to H^{\pm\pm}H^{\mp}. We compare the discovery
potential for the signatures of exactly four leptons and at least three leptons
in the final state, using the same set of cuts. We have carried out fast
detector simulations at the LHC for both signal and backgrounds for a wide
range of values of the charged Higgs mass. We find that the use of the latter
channel can substantially improve the detection prospects of the doubly charged
Higgs boson at the LHC.Comment: 18 pages, 6 figures, discussion of QCD backgrounds added, version to
  appear in JHE
Displaced Higgs production in type III seesaw

We point out that the type III seesaw mechanism introducing fermion triplets
predicts peculiar Higgs boson signatures of displaced vertices with two b jets
and one or two charged particles which can be cleanly identified. In a
supersymmetric theory, the scalar partner of the fermion triplet contains a
neutral dark matter candidate which is almost degenerate with its charged
components. A Higgs boson can be produced together with such a dark matter
triplet in the cascade decay chain of a strongly produced squark or gluino.
When the next lightest supersymmetric particle (NLSP) is bino/wino-like, there
appears a Higgs boson associated with two charged tracks of a charged lepton
and a heavy charged scalar at a displacement larger than about 1 mm. The
corresponding production cross-section is about 0.5 fb for the squark/gluino
mass of 1 TeV. In the case of the stau NLSP, it decays mainly to a Higgs boson
and a heavy charged scalar whose decay length is larger than 0.1 mm for the
stau NLSP mixing with the left-handed stau smaller than 0.3. As this process
can have a large cascade production $\sim 2$ pb for the squark/gluino mass
$\sim 1$ TeV, one may be able to probe it at the early stage of the LHC
experiment.Comment: 10 pages, 5 figure
Asymptotic symmetries of three-dimensional gravity coupled to
  higher-spin fields

We discuss the emergence of W-algebras as asymptotic symmetries of
higher-spin gauge theories coupled to three-dimensional Einstein gravity with a
negative cosmological constant. We focus on models involving a finite number of
bosonic higher-spin fields, and especially on the example provided by the
coupling of a spin-3 field to gravity. It is described by a SL(3) \times SL(3)
Chern-Simons theory and its asymptotic symmetry algebra is given by two copies
of the classical W_3-algebra with central charge the one computed by Brown and
Henneaux in pure gravity with negative cosmological constant.Comment: 38 pages; version to be published in JHEP; typos corrected in eqs.
  (2.9) and (2.54
Extracting the Dark Matter Mass from Single Stage Cascade Decays at the
  LHC

We explore a variant on the MT2 kinematic variable which enables dark matter
mass measurements for simple, one stage, cascade decays. This will prove useful
for constraining a subset of supersymmetric processes, or a class of
leptophilic dark matter models at the LHC. We investigate the statistical reach
of these measurements and discuss which sources of error have the largest
effects. For example, we find that using only single stage cascade decays with
initial state radiation, a measurement of a 150 GeV dark matter candidate can
be made to O(10%) for a parent mass of 300 GeV with a production cross section
of 100 fb and 100 fb^(-1) of integrated luminosity.Comment: 23 Pages, 14 Figures, 2 Appendice
Heterotic Flux Attractors

We find attractor equations describing moduli stabilization for heterotic
compactifications with generic SU(3)-structure. Complex structure and K\"ahler
moduli are treated on equal footing by using SU(3)xSU(3)-structure at
intermediate steps. All independent vacuum data, including VEVs of the
stabilized moduli, is encoded in a pair of generating functions that depend on
fluxes alone. We work out an explicit example that illustrates our methods.Comment: 37 pages, references and clarifications adde
Complete Phase Diagrams for a Holographic Superconductor/Insulator
  System

The gravitational dual of an insulator/superconductor transition driven by
increasing the chemical potential has recently been constructed. However, the
system was studied in a probe limit and only a part of the phase diagram was
obtained. We include the backreaction and construct the complete phase diagram
for this system. For fixed chemical potential there are typically two phase
transitions as the temperature is lowered. Surprisingly, for a certain range of
parameters, the system first becomes a superconductor and then becomes an
insulator as the temperature approaches zero. As a byproduct of our analysis,
we also construct the gravitational dual of a Bose-Einstein condensate of
glueballs in a confining gauge theory.Comment: 19 pages; v2: references adde
Search for the Elusive Higgs Boson Using Jet Structure at LHC

We consider the production of a light non-standard model Higgs boson of order
$100~\GEV$ with an associated $W$ boson at CERN Large Hadron Collider. We focus
on an interesting scenario that, the Higgs boson decays predominately into two
light scalars $\chi$ with mass of few GeV which sequently decay into four
gluons, i.e. $h\to 2\chi \to 4g$. Since $\chi$ is much lighter than the Higgs
boson, it will be highly boosted and its decay products, the two gluons, will
move close to each other, resulting in a single jet for $\chi$ decay in the
detector. By using electromagnetic calorimeter-based and jet substructure
analyses, we show in two cases of different $\chi$ masses that it is quite
promising to extract the signal of Higgs boson out of large QCD background.Comment: 20 pages, 7 figure