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 Washington, D.C. : United States. Dept. of Energy. ; Oak Ridge, Tenn. : distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2017
 Description
 Book — 1 online resource (50 p.) : digital, PDF file.
 Summary

We find a simple relation between twodimensional BPS N = 2 superconformal blocks and bosonic Virasoro conformal blocks, which allows us to analyze the crossing equations for BPS 4point functions in unitary (2, 2) superconformal theories numerically with semidefinite programming. Here, we constrain gaps in the nonBPS spectrum through the operator product expansion of BPS operators, in ways that depend on the moduli of exactly marginal deformations through chiral ring coefficients. In some cases, our bounds on the spectral gaps are observed to be saturated by free theories, by N = 2 Liouville theory, and by certain LandauGinzburg models.
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 Washington, D.C. : United States. Dept. of Energy. Office of Science ; Oak Ridge, Tenn. : distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2017
 Description
 Book — 1 online resource (43 p.) : digital, PDF file.
 Summary

In this paper we present a beautifully consistent web of evidence for the existence of interacting 4d rank1 $ \mathcal{N} $ = 2 SCFTs obtained from gauging discrete subgroups of global symmetries of other existing 4d rank1 $ \mathcal{N} $ = 2 SCFTs. The global symmetries that can be gauged involve a nontrivial combination of discrete subgroups of the U(1)<sub>R</sub>, lowenergy EM duality group SL(2, Z), and the outer automorphism group of the flavor symmetry algebra, Out(F ). The theories that we construct are remarkable in many ways: (i) two of them have exceptional F<sub>4</sub> and G<sub>2</sub> flavor groups; (ii) they substantially complete the picture of the landscape of rank1 $ \mathcal{N} $ = 2 SCFTs as they realize all but one of the remaining consistent rank1 SeibergWitten geometries that we previously constructed but were not associated to known SCFTs; and (iii) some of them have enlarged $ \mathcal{N} $ = 3 SUSY, and have not been previously constructed. They are also examples of SCFTs which violate the ShapereTachikawa relation between the conformal central charges and the scaling dimension of the Coulomb branch vev. Here, we propose a modification of the formulas computing these central charges from the topologically twisted Coulomb branch partition function which correctly compute them for discretely gauged theories.
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 Washington, D.C. : United States. Dept. of Energy. Office of Science ; Oak Ridge, Tenn. : distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2017
 Description
 Book — 1 online resource (p. 135) : digital, PDF file.
 Summary

Compactifying N = (1, 0) theories on a torus, with additional fluxes for global symmetries, we obtain N = 1 supersymmetric theories in four dimensions. It is shown that for many choices of flux these models are toric quiver gauge theories with singlet fields. Particularly we compare the anomalies deduced from the description of the six dimensional theory and the anomalies of the quiver gauge theories. Also, we give predictions for anomalies of fourdimensional theories corresponding to general compactifi cations of M5branes probing C<sup>2</sup>/Z<sub>k</sub> singularities.
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 Washington, D.C. : United States. Dept. of Energy. ; Oak Ridge, Tenn. : distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2017
 Description
 Book — 1 online resource (Article No. 112) : digital, PDF file.
 Summary

We reformulate the scattering amplitudes of 4D at space gauge theory and gravity in the language of a 2D CFT on the celestial sphere. The resulting CFT structure exhibits an OPE constructed from 4D collinear singularities, as well as infinitedimensional KacMoody and Virasoro algebras encoding the asymptotic symmetries of 4D at space. We derive these results by recasting 4D dynamics in terms of a convenient foliation of flat space into 3D Euclidean AdS and Lorentzian dS geometries. Treelevel scattering amplitudes take the form of Witten diagrams for a continuum of (A)dS modes, which are in turn equivalent to CFT correlators via the (A)dS/CFT dictionary. The Ward identities for the 2D conserved currents are dual to 4D soft theorems, while the bulkboundary propagators of massless (A)dS modes are superpositions of the leading and subleading Weinberg soft factors of gauge theory and gravity. In general, the massless (A)dS modes are 3D ChernSimons gauge fields describing the soft, single helicity sectors of 4D gauge theory and gravity. Consistent with the topological nature of ChernSimons theory, AharonovBohm effects record the \tracks" of hard particles in the soft radiation, leading to a simple characterization of gauge and gravitational memories. Soft particle exchanges between hard processes define the KacMoody level and Virasoro central charge, which are thereby related to the 4D gauge coupling and gravitational strength in units of an infrared cutoff. Lastly, we discuss a toy model for black hole horizons via a restriction to the Rindler region.
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 Washington, D.C. : United States. Dept. of Energy. Office of Basic Energy Sciences ; Oak Ridge, Tenn. : distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2017
 Description
 Book — 1 online resource (Article No. 15461) : digital, PDF file.
 Summary

Freeelectron lasers providing ultrashort highbrightness pulses of Xray radiation have great potential for a wide impact on science, and are a critical element for unravelling the structural dynamics of matter. To fully harness this potential, we must accurately know the Xray properties: intensity, spectrum and temporal profile. Owing to the inherent fluctuations in freeelectron lasers, this mandates a full characterization of the properties for each and every pulse. While diagnostics of these properties exist, they are often invasive and many cannot operate at a highrepetition rate. Here, we present a technique for circumventing this limitation. Employing a machine learning strategy, we can accurately predict Xray properties for every shot using only parameters that are easily recorded at highrepetition rate, by training a model on a small set of fully diagnosed pulses. Lastly, this opens the door to fully realizing the promise of nextgeneration highrepetition rate Xray lasers.
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 Washington, D.C. : United States. Office of the Assistant Secretary for Nuclear Energy ; Oak Ridge, Tenn. : distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2017
 Description
 Book — 1 online resource (390 p.) : digital, PDF file.
 Summary

A series of up to seven irradiation experiments are planned for the Advanced Gas Reactor (AGR) Fuel Development and Quantification Program, with irradiation completed at the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL) for the first experiment (i.e., AGR1) in November 2009 for an effective 620 full power days. The objective of the AGR1 experiment was primarily to provide lessons learned on the multicapsule test train design and to provide early data on fuel performance for use in fuel fabrication process development and postirradiation safety testing data at high temperatures. This report describes the advanced microscopy and microanalysis results on selected AGR1 coated particles.
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 Washington, D.C. : United States. Dept. of Energy. ; Oak Ridge, Tenn. : distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2017
 Description
 Book — 1 online resource (p. 200209) : digital, PDF file.
 Summary

The microscopic nature of the XYZ states remains an unsettled topic. We show how a thorough amplitude analysis of the data can help constraining models of these states. Specifically, we consider the case of the Z<sub>c</sub>(3900) peak and discuss possible scenarios of a QCD state, virtual state, or a kinematical enhancement. Here, we conclude that current data are not precise enough to distinguish between these hypotheses, however, the method we propose, when applied to the forthcoming highstatistics measurements should shed light on the nature of these exotic enhancements.
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 Washington, D.C. : United States. Dept. of Energy. Office of Science ; Oak Ridge, Tenn. : distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2017
 Description
 Book — 1 online resource (Article No. 56) : digital, PDF file.
 Summary

Here, we describe in detail the method used in our previous work arXiv:1611.10344 to study the WilsonFisher critical points nearby generalized free CFTs, exploiting the analytic structure of conformal blocks as functions of the conformal dimension of the exchanged operator. Our method is equivalent to the mechanism of conformal multiplet recombination set up by null states. We also compute, to the first nontrivial order in the εexpansion, the anomalous dimensions and the OPE coefficients of infinite classes of scalar local operators using just CFT data. We study singlescalar and O(N)invariant theories, as well as theories with multiple deformations. When available we agree with older results, but we also produce a wealth of new ones. Furthermore, unitarity and crossing symmetry are not used in our approach and we are able to apply our method to nonunitary theories as well. Some implications of our results for the study of the nonunitary theories containing partially conserved higherspin currents are briefly mentioned.
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9. Angular momentum conservation law in lightfront quantum field theory [electronic resource]. [2017]
 Washington, D.C. : United States. Dept. of Energy. High Energy Physics Division ; Oak Ridge, Tenn. : distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2017
 Description
 Book — 1 online resource (36 pages) : digital, PDF file.
 Summary

We prove the Lorentz invariance of the angular momentum conservation law and the helicity sum rule for relativistic composite systems in the lightfront formulation. We explicitly show that j 3 , the z component of the angular momentum remains unchanged under Lorentz transformations generated by the lightfront kinematical boost operators. The invariance of j 3 under Lorentz transformations is a feature unique to the front form. Applying the Lorentz invariance of the angular quantum number in the front form, we obtain a selection rule for the orbital angular momentum which can be used to eliminate certain interaction vertices in QED and QCD. We also generalize the selection rule to any renormalizable theory and show that there exists an upper bound on the change of orbital angular momentum in scattering processes at any fixed order in perturbation theory.
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 Washington, D.C. : United States. National Nuclear Security Administration ; Oak Ridge, Tenn. : distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2017
 Description
 Book — 1 online resource (53 p.) : digital, PDF file.
 Summary

No abstract provided.
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 Washington, D.C. : United States. Dept. of Energy. High Energy Physics Division ; Oak Ridge, Tenn. : distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2017
 Description
 Book — 1 online resource (p. 512–516) : digital, PDF file.
 Summary

Here, the exoHiggs model can accommodate a successful baryogenesis mechanism that closely mirrors electroweak baryogenesis in the Standard Model, but avoids its shortcomings. We extend the exo Higgs model by the addition of a singlet complex scalar. In our model, Χ can be a viable asymmetric dark matter (ADM) candidate. We predict the mass of the ADM particle to be m<sub>x</sub> ≈ 1.3 GeV. The leptophilic couplings of can provide for efficient annihilation of the ADM pairs. We also discuss the LHC signals of our scenario, and in particular the production and decays of exoleptons which would lead to "lepton pair plus missing energy" final states. Our model typically predicts potentially detectable gravitational waves originating from the assumed strong first order phase transition at a temperature of ~TeV. If the model is further extended to include new heavy vectorlike fermions, e.g. from an ultraviolet extension, Χ couplings could explain the ~3.5 muon g – 2 anomaly.
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 Washington, D.C. : United States. Dept. of Energy. ; Oak Ridge, Tenn. : distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2017
 Description
 Book — 1 online resource (24 p.) : digital, PDF file.
 Summary

Here, we develop an asymptotic perturbation theory for the large logarithmic behavior of the nonlinear integrodifferential equation describing the soft correlations of QCD jet measurements, the BanfiMarchesiniSmye (BMS) equation. Furthermore, this equation captures the latetime evolution of radiating color dipoles after a hard collision. This allows us to prove that at large values of the control variable (the nonglobal logarithm, a function of the infrared energy scales associated with distinct hard jets in an event), the distribution has a gaussian tail. We also compute the decay width analytically, giving a closed form expression, and find it to be jet geometry independent, up to the number of legs of the dipole in the active jet. By enabling the asymptotic expansion we find that the perturbative seed is correct; we perturb around an anzats encoding formally no real emissions, an intuition motivated by the buffer region found in jet dynamics. This must be supplemented with the correct application of the BFKL approximation to the BMS equation in collinear limits. Comparing to the asymptotics of the conformally related evolution equation encountered in smallx physics, the BalitiskyKovchegov (BK) equation, we find that the asymptotic form of the nonglobal logarithms directly maps to the blackdisc unitarity limit of the BK equation, despite the contrasting physical pictures. Indeed, we recover the equations of saturation physics in the final state dynamics of QCD.
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 Washington, D.C. : United States. Dept. of Energy. High Energy Physics Division ; Oak Ridge, Tenn. : distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2017
 Description
 Book — 1 online resource (Article No. 075017) : digital, PDF file.
 Summary

Sterile neutrinos can be generated in the early universe through oscillations with active neutrinos and represent a popular and wellstudied candidate for our universe's dark matter. Stringent constraints from Xray and gammaray line searches, however, have excluded the simplest of such models. In this letter, we propose a novel alternative to the standard scenario in which the mixing angle between the sterile and active neutrinos is a dynamical quantity, induced through interactions with a light axionlike field. As the energy density of the axionlike particles is diluted by Hubble expansion, the degree of mixing is reduced at late times, suppressing the decay rate and easily alleviating any tension with Xray or gammaray constraints. We present a simple model which illustrates the phenomenology of this scenario, and also describe a framework in which the QCD axion is responsible for the production of sterile neutrinos in the early universe.
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 Washington, D.C. : United States. Dept. of Energy. High Energy Physics Division ; Oak Ridge, Tenn. : distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2017
 Description
 Book
 Summary

The Fourier coefficients v[2] and v[3] characterizing the anisotropy of the azimuthal distribution of charged particles produced in PbPb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV are measured with data collected by the CMS experiment. The measurements cover a broad transverse momentum range, pt= 1100 GeV. The analysis focuses on pt > 10 GeV range, where anisotropic azimuthal distributions should reflect the pathlength dependence of parton energy loss in the created medium. Results are presented in several bins of PbPb collision centrality, spanning the 60x% most central events. The v[2] coefficient is measured with the scalar product and the multiparticle cumulant methods, which have different sensitivities to the initialstate fluctuations. The values of both methods remain positive up to pt ~ 70 GeV, in all examined centrality classes. The v[3] coefficient, only measured with the scalar product method, tends to zero for pt >~ 20 GeV. Comparisons between theoretical calculations and data provide new constraints on the pathlength dependence of parton energy loss in heavy ion collisions and highlight the importance of the initialstate fluctuations.
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 Washington, D.C. : United States. Dept. of Energy. High Energy Physics Division ; Oak Ridge, Tenn. : distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2017
 Description
 Book — 1 online resource (22 p.) : digital, PDF file.
 Summary

Here, we investigate the potential of using deep learning techniques to reject background events in searches for neutrinoless double beta decay with high pressure xenon time projection chambers capable of detailed track reconstruction. The differences in the topological signatures of background and signal events can be learned by deep neural networks via training over many thousands of events. These networks can then be used to classify further events as signal or background, providing an additional background rejection factor at an acceptable loss of efficiency. The networks trained in this study performed better than previous methods developed based on the use of the same topological signatures by a factor of 1.2 to 1.6, and there is potential for further improvement.
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 Washington, D.C. : United States. Dept. of Energy. ; Oak Ridge, Tenn. : distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2017
 Description
 Book — 1 online resource (Article No. 15850) : digital, PDF file.
 Summary

Quantum spin Hall system can exhibit exotic spin transport phenomena, mediated by its topological edge states. The concept of bending strain engineering to tune the spin transport properties of a quantum spin Hall system is demonstrated. Here, we show that bending strain can be used to control the spin orientation of counterpropagating edge states of a quantum spin system to generate a nonzero spin current. This physics mechanism can be applied to effectively tune the spin current and pure spin current decoupled from charge current in a quantum spin Hall system by control of its bending curvature. Moreover, the curved quantum spin Hall system can be achieved by the concept of topological nanomechanical architecture in a controllable way, as demonstrated by the material example of Bi/Cl/Si(111) nanofilm. This concept of bending strain engineering of spins via topological nanomechanical architecture affords a promising route towards the realization of topological nanomechanospintronics.
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 Washington, D.C. : United States. Dept. of Energy. High Energy Physics Division ; Oak Ridge, Tenn. : distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2017
 Description
 Book
 Summary

Experimental Particle Physics has been at the forefront of analyzing the worlds largest datasets for decades. The HEP community was the rst to develop suitable software and computing tools for this task. In recent times, new toolkits and systems collectively called Big Data technologies have emerged to support the analysis of Petabyte and Exabyte datasets in industry. While the principles of data analysis in HEP have not changed (ltering and transforming experimentspecic data formats), these new technologies use dierent approaches and promise a fresh look at analysis of very large datasets and could potentially reduce the timetophysics with increased interactivity. In this talk, we present an active LHC Run 2 analysis, searching for dark matter with the CMS detector, as a testbed for Big Data technologies. We directly compare the traditional NTuplebased analysis with an equivalent analysis using Apache Spark on the Hadoop ecosystem and beyond. In both cases, we start the analysis with the ocial experiment data formats and produce publication physics plots. We will discuss advantages and disadvantages of each approach and give an outlook on further studies needed. 1.
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 Washington, D.C. : United States. Dept. of Energy. High Energy Physics Division ; Oak Ridge, Tenn. : distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2017
 Description
 Book — 1 online resource (Article No. 022004 ): digital, PDF file.
 Summary

Soft function relevant for transversemomentum resummation for DrellYan or Higgs production at hadron colliders are computed through to three loops in the expansion of strong coupling, with the help of bootstrap technique and supersymmetric decomposition. The corresponding rapidity anomalous dimension is extracted. An intriguing relation between anomalous dimensions for transversemomentum resummation and threshold resummation is found.
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 Washington, D.C. : United States. Dept. of Energy. High Energy Physics Division ; Oak Ridge, Tenn. : distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2017
 Description
 Book — 1 online resource (Article No. 107) : digital, PDF file.
 Summary

Here, we study boundary scattering in the $\phi^4$ model on a halfline with a oneparameter family of Neumanntype boundary conditions. A rich variety of phenomena is observed, which extends previouslystudied behaviour on the full line to include regimes of nearelastic scattering, the restoration of a missing scattering window, and the creation of a kink or oscillon through the collisioninduced decay of a metastable boundary state. We also study the decay of the vibrational boundary mode, and explore different scenarios for its relaxation and for the creation of kinks.
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20. Bulk viscous corrections to screening and damping in QCD at high temperatures [electronic resource]. [2017]
 Washington, D.C. : United States. Dept. of Energy. Office of Nuclear Physics ; Oak Ridge, Tenn. : distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2017
 Description
 Book — 1 online resource (Article No. 123) : digital, PDF file.
 Summary

Nonequilibrium corrections to the distribution functions of quarks and gluons in a hot and dense QCD medium modify the \hard thermal loops" (HTL). The HTLs determine the retarded, advanced, and symmetric (timeordered) propagators for gluons with soft momenta as well as the Debye screening and Landau damping mass scales. Here, we compute such corrections to a thermal as well as to a nonthermal fixed point. The screening and damping mass scales are sensitive to the bulk pressure and hence to (pseudo) critical dynamical scaling of the bulk viscosity in the vicinity of a secondorder critical point. This could be reected in the properties of quarkonium bound states in the deconfined phase and in the dynamics of soft gluon fields.
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