Journal of High Energy Physics

http://link.springer.com/journal/13130

List of Papers (Total 9,786)

Refining the scalar and tensor contributions in τ → πππν τ decays

In this article we analyze the contribution from intermediate spin-0 and spin-2 resonances to the τ → νπππ decay by means of a chiral invariant Lagrangian incorporating these mesons. In particular, we study the corresponding axial-vector form-factors. The advantage of this procedure with respect to previous analyses is that it incorporates chiral (and isospin) invariance and, ...

Relativistic hydrodynamic attractors with broken symmetries: non-conformal and non-homogeneous

Standard textbooks will state that hydrodynamics requires near-equilibrium to be applicable. Recently, however, out-of-equilibrium attractor solutions for hydrodynamics have been found in kinetic theory and holography in systems with a high degree of symmetry, suggesting the possibility of a genuine out-of-equilibrium formulation of hydrodynamics. This work demonstrates that ...

Kink dynamics in a parametric ϕ 6 system: a model with controllably many internal modes

We explore a variant of the ϕ 6 model originally proposed in Phys. Rev. D 12 (1975) 1606 as a prototypical, so-called, “bag” model in which domain walls play the role of quarks within hadrons. We examine the steady state of the model, namely an apparent bound state of two kink structures. We explore its linearization, and we find that, as a function of a parameter controlling the ...

An alternative lattice field theory formulation inspired by lattice supersymmetry

We propose an unconventional formulation of lattice field theories which is quite general, although originally motivated by the quest of exact lattice supersymmetry. Two long standing problems have a solution in this context: 1) Each degree of freedom on the lattice corresponds to 2 d degrees of freedom in the continuum, but all these doublers have (in the case of fermions) the ...

Diagrammatic Hopf algebra of cut Feynman integrals: the one-loop case

We construct a diagrammatic coaction acting on one-loop Feynman graphs and their cuts. The graphs are naturally identified with the corresponding (cut) Feynman integrals in dimensional regularization, whose coefficients of the Laurent expansion in the dimensional regulator are multiple polylogarithms (MPLs). Our main result is the conjecture that this diagrammatic coaction ...

Comments on supersymmetric renormalization in two-dimensional curved spacetime

In this technical note we introduce a manifestly gauge-invariant and supersymmetric procedure to regularize and renormalize one-loop divergences of chiral multiplets in two-dimensional \( \mathcal{N} \) = (2, 2) theories in curved spacetime. We apply the method, a version of Pauli-Villars regularization, to known examples of supersymmetric localization and demonstrate that the ...

The photon content of the proton

The photon PDF of the proton is needed for precision comparisons of LHC cross sections with theoretical predictions. In a recent paper, we showed how the photon PDF could be determined in terms of the electromagnetic proton structure functions F 2 and F L measured in electron-proton scattering experiments, and gave an explicit formula for the PDF including all terms up to ...

Collider probes of axion-like particles

Axion-like particles (ALPs), which are gauge-singlets under the Standard Model (SM), appear in many well-motivated extensions of the SM. Describing the interactions of ALPs with SM fields by means of an effective Lagrangian, we discuss ALP decays into SM particles at one-loop order, including for the first time a calculation of the a → πππ decay rates for ALP masses below a few ...

Circle compactification and ’t Hooft anomaly

Anomaly matching constrains low-energy physics of strongly-coupled field theories, but it is not useful at finite temperature due to contamination from high-energy states. The known exception is an ’t Hooft anomaly involving one-form symmetries as in pure SU(N ) Yang-Mills theory at θ = π. Recent development about large-N volume independence, however, gives us a circumstantial ...

Generalized Toda theory from six dimensions and the conifold

Recently, a physical derivation of the Alday-Gaiotto-Tachikawa correspondence has been put forward. A crucial role is played by the complex Chern-Simons theory arising in the 3d-3d correspondence, whose boundary modes lead to Toda theory on a Riemann surface. We explore several features of this derivation and subsequently argue that it can be extended to a generalization of the AGT ...

Perfectly invisible \( \mathcal{P}\mathcal{T} \) -symmetric zero-gap systems, conformal field theoretical kinks, and exotic nonlinear supersymmetry

We investigate a special class of the \( \mathcal{P}\mathcal{T} \) -symmetric quantum models being perfectly invisible zero-gap systems with a unique bound state at the very edge of continuous spectrum of scattering states. The family includes the \( \mathcal{P}\mathcal{T} \) -regularized two particle Calogero systems (conformal quantum mechanics models of de Alfaro-Fubini-Furlan) ...

Structure constants of defect changing operators on the 1/2 BPS Wilson loop

We study three-point functions of operators on the 1/2 BPS Wilson loop in planar \( \mathcal{N} \) = 4 super Yang-Mills theory. The operators we consider are "defect changing operators", which change the scalar coupled to the Wilson loop. We first perform the computation at two loops in general set-ups, and then study a special scaling limit called the ladders limit, in which the ...

Measuring properties of a heavy Higgs boson in the H→ZZ→4ℓ decay

In many extensions of the standard model, there exist a few extra Higgs bosons. Suppose a heavy neutral Higgs boson H is discovered at the LHC, one could then investigate CP and \( \mathrm{C}\mathrm{P}\tilde{\mathrm{T}} \) properties of its couplings to a pair of Z bosons through H → ZZ → 4ℓ. We use the helicity-amplitude method to write down the most general form for the angular ...

Is there a breakdown of effective field theory at the horizon of an extremal black hole?

Linear perturbations of extremal black holes exhibit the Aretakis instability, in which higher derivatives of a scalar field grow polynomially with time along the event horizon. This suggests that higher derivative corrections to the classical equations of motion may become large, indicating a breakdown of effective field theory at late time on the event horizon. We investigate ...

Non-perturbative determination of the Λ-parameter in the pure SU(3) gauge theory from the twisted gradient flow coupling

We evaluate the Λ-parameter in the \( \overline{\mathrm{MS}} \) scheme for the pure SU(3) gauge theory with the twisted gradient flow (TGF) method. A running coupling constant g TGF 2 (1/L) is defined in a finite volume box with size of L 4 with the twisted boundary condition. This defines the TGF scheme. Using the step scaling method for the TGF coupling with lattice simulations, ...

Transverse vetoes with rapidity cutoff in SCET

We consider di-jet production in hadron collisions where a transverse veto is imposed on radiation for (pseudo-)rapidities in the central region only, where this central region is defined with rapidity cutoff. For the case where the transverse measurement (e.g., transverse energy or min p T for jet veto) is parametrically larger relative to the typical transverse momentum beyond ...

Exceptional \( \mathcal{N}=3 \) theories

We present a new construction of four dimensional \( \mathcal{N}=3 \) theories, given by M5 branes wrapping a T 2 in an M-theory U-fold background. The resulting setup generalizes the one used in the usual class \( \mathcal{S} \) construction of four dimensional theories by using an extra discrete symmetry on the M5 worldvolume. Together with the M-theory U-fold description of (0, ...

Nonviolent unitarization: basic postulates to soft quantum structure of black holes

A first-principles approach to the unitarity problem for black holes is systematically explored, based on the postulates of 1) quantum mechanics 2) the ability to approximately locally divide quantum gravitational systems into subsystems 3) correspondence with quantum field theory predictions for appropriate observers and (optionally) 4) universality of new gravitational effects. ...

On-shell gauge invariant three-point amplitudes

Assuming locality, Lorentz invariance and parity conservation we obtain a set of differential equations governing the 3-point interactions of massless bosons, which in turn determines the polynomial ring of these amplitudes. We derive all possible 3-point interactions for tensor fields with polarisations that have total symmetry and mixed symmetry under permutations of Lorentz ...

Evidence for the \( H\to b\overline{b} \) decay with the ATLAS detector

A search for the decay of the Standard Model Higgs boson into a \( b\overline{b} \) pair when produced in association with a W or Z boson is performed with the ATLAS detector. The analysed data, corresponding to an integrated luminosity of 36.1 fb−1, were collected in proton-proton collisions in Run 2 of the Large Hadron Collider at a centre-of-mass energy of 13 TeV. Final states ...

Subleading power corrections to the pion-photon transition form factor in QCD

We reconsider QCD factorization for the leading power contribution to the γ * γ → π 0 form factor F γ*γ→π 0(Q 2) at one loop using the evanescent operator approach, and demonstrate the equivalence of the resulting factorization formulae derived with distinct prescriptions of γ 5 in dimensional regularization. Applying the light-cone QCD sum rules (LCSRs) with photon distribution ...

Bose-Einstein correlations of same-sign charged pions in the forward region in pp collisions at \( \sqrt{s}=7 \) TeV

Bose-Einstein correlations of same-sign charged pions, produced in proton-proton collisions at a 7 TeV centre-of-mass energy, are studied using a data sample collected by the LHCb experiment. The signature for Bose-Einstein correlations is observed in the form of an enhancement of pairs of like-sign charged pions with small four-momentum difference squared. The charged-particle ...

Measurement of the B ± production cross-section in pp collisions at \( \sqrt{s}=7 \) and 13 TeV

The production of B ± mesons is studied in pp collisions at centre-of-mass energies of 7 and 13 TeV, using B ± → J/ψ K ± decays and data samples corresponding to 1.0 fb−1 and 0.3 fb−1, respectively. The production cross-sections summed over both charges and integrated over the transverse momentum range 0 < p T < 40 GeV/c and the rapidity range 2.0 < y < 4.5 are measured to be $$ ...

Flat monodromies and a Moduli Space Size Conjecture

We investigate how super-Planckian axions can arise when type IIB 3-form flux is used to restrict a two-axion field space to a one-dimensional winding trajectory. If one does not attempt to address notoriously complicated issues like Kähler moduli stabilization, SUSY-breaking and inflation, this can be done very explicitly. We show that the presence of flux generates flat ...

Embedding three-dimensional bosonization dualities into string theory

We give simple string theory embeddings of several recently introduced dualities between 2+1-dimensional Chern-Simons matter theories using probe brane holography. Our construction is reliable in the limit of a large number of colors N with fixed Chern-Simons level k.