Journal of High Energy Physics

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

List of Papers (Total 9,336)

Open/closed topological \( \mathbb{C}{\mathbb{P}^{{1}}} \) sigma model revisited

We consider the topological sigma-model on Riemann surfaces with genus g and h holes, and target space \( \mathbb{C}{\mathbb{P}^1} \cong {S^2} \). We calculate the correlation functions of bulk and boundary operators, and study the symmetries of the model and its most general deformation. We study the open/closed topological field theory (TFT) correspondence by summing up the ...

Holography for Einstein-Maxwell-dilaton theories from generalized dimensional reduction

We show that a class of Einstein-Maxwell-Dilaton (EMD) theories are re- lated to higher dimensional AdS-Maxwell gravity via a dimensional reduction over com- pact Einstein spaces combined with continuation in the dimension of the compact space to non-integral values (‘generalized dimensional reduction’). This relates (fairly complicated) black hole solutions of EMD theories to ...

Holographic Fermi and non-Fermi liquids with transitions in dilaton gravity

We study the two-point function for fermionic operators in a class of strongly coupled systems using the gauge-gravity correspondence. The gravity description includes a gauge field and a dilaton which determines the gauge coupling and the potential energy. Extremal black brane solutions in this system typically have vanishing entropy. By analyzing a charged fermion in these ...

Distinguishing among technicolor/warped scenarios in dileptons

Models of dynamical electroweak symmetry breaking usually include new spin-1 resonances, whose couplings and masses have to satisfy electroweak precision tests. We propose to use dilepton searches to probe the underlying structure responsible for satisfying these. Using the invariant mass spectrum and charge asymmetry, we can determine the number, parity, and isospin of these ...

Dissipative effects in the effective field theory of inflation

We generalize the effective field theory of single clock inflation to include dissipative effects. Working in unitary gauge we couple a set of composite operators, \( {\mathcal{O}_{{\mu \nu }}}_{ \ldots } \), in the effective action which is constrained solely by invariance under time-dependent spatial diffeomorphisms. We restrict ourselves to situations where the degrees of ...

Light NMSSM Higgs bosons in SUSY cascade decays at the LHC

An interesting feature of the next-to-minimal supersymmetric standard model (NMSSM) is that one or more Higgs bosons may be comparably light (\({M_{{{H_i}}}} < {M_Z}\)) without being in conflict with current experimental bounds. Due to a large singlet component, their direct production in standard channels at the Large Hadron Collider (LHC) is suppressed. We demonstrate that there ...

NNLL resummation for squark-antisquark pair production at the LHC

We consider the resummation of soft gluon emission for squark-antisquark pair-production at the LHC at next-to-next-to-leading-logarithmic (NNLL) accuracy in the framework of the minimal supersymmetric standard model. We present the analytical ingredients needed for the calculation and provide numerical predictions for the LHC at centre-of-mass energies of 7 and 14 TeV. We find a ...

Heavy flavor simplified models at the LHC

We consider a comprehensive set of simplified models that contribute to final states with top and bottom quarks at the LHC. These simplified models are used to create minimal search strategies that ensure optimal coverage of new heavy flavor physics involving the pair production of color octets and triplets. We provide a set of benchmarks that are representative of model space, ...

Hamilton-Jacobi renormalization for Lifshitz spacetime

Just like AdS spacetimes, Lifshitz spacetimes require counterterms in order to make the on-shell value of the bulk action finite. We study these counterterms using the Hamilton-Jacobi method. Rather than imposing boundary conditions from the start, we will derive suitable boundary conditions by requiring that divergences can be canceled using only local counterterms. We will ...

Exclusive γγ → μ + μ − production in proton-proton collisions at \( \sqrt {s} = {7} \) TeV

A measurement of the exclusive two-photon production of muon pairs in proton-proton collisions at \( \sqrt {s} = {7} \) TeV, pp → pμ + μ −p, is reported using data corresponding to an integrated luminosity of 40 pb−1. For muon pairs with invariant mass greater than 11.5 GeV, transverse momentum p T (μ) > 4 GeV and pseudorapidity |η(μ)| < 2.1, a fit to the dimuon p T (μ + μ −) ...

Lattice QCD determination of m b , f B and f Bs with twisted mass Wilson fermions

We present a lattice QCD determination of the b quark mass and of the B and B s decay constants, performed with N f = 2 twisted mass Wilson fermions, by simulating at four values of the lattice spacing. In order to study the b quark on the lattice, two methods are adopted in the present work, respectively based on suitable ratios with exactly known static limit and on the ...

Integrable structure, W-symmetry and AGT relation

In these notes we consider integrable structure of the conformal field theory with the algebra of symmetries \( \mathcal{A} = {W_n} \otimes H \), where W n is W–algebra and H is Heisenberg algebra. We found the system of commuting Integrals of Motion with relatively simple properties. In particular, this system has very simple spectrum and the matrix elements of special primary ...

External leg corrections in the unitarity method

Unitarity cuts diverge in the channel of a single massive external fermion. We propose an off-shell continuation of the momentum that allows a finite evaluation of the unitarity cuts. If the cut is taken with complete amplitudes on each side, our continuation and expansion around the on-shell configuration produces the finite contribution to the bubble coefficient. Finite parts in ...

A method to estimate the boson mass and to optimise sensitivity to helicity correlations of τ + τ − final states

In proton-proton collisions at LHC energies, Z 0 and low mass Higgs bosons would be produced with high and predominantly longitudinal boost with respect to the beam axis. This note describes a new analysis tool devised to handle this situation in cases when such bosons decay to a pair of τ -leptons. The tool reconstructs the rest frame of the τ + τ − pair by finding the boost that ...

R-parity conservation via the Stueckelberg mechanism: LHC and Dark Matter Signals

We investigate the connection between the conservation of R-parity in super- symmetry and the Stueckelberg mechanism for the mass generation of the B − L vector gauge boson. It is shown that with universal boundary conditions for soft terms of sfermions in each family at the high scale and with the Stueckelberg mechanism for generating mass for the B − L gauge boson present in the ...

Liouville integrable defects: the non-linear Schrödinger paradigm

A systematic approach to Liouville integrable defects is proposed, based on an underlying Poisson algebraic structure. The non-linear Schrödinger model in the presence of a single particle-like defect is investigated through this algebraic approach. Local integrals of motions are constructed as well as the time components of the corresponding Lax pairs. Continuity conditions ...

Analytic result for the two-loop six-point NMHV amplitude in \( \mathcal{N} = {4} \) super Yang-Mills theory

We provide a simple analytic formula for the two-loop six-point ratio function of planar \( \mathcal{N} = {4} \) super Yang-Mills theory. This result extends the analytic knowledge of multi-loop six-point amplitudes beyond those with maximal helicity violation. We make a natural ansatz for the symbols of the relevant functions appearing in the two-loop amplitude, and impose various ...

Cosmological solutions with massive gravitons in the bigravity theory

We present solutions describing homogeneous and isotropic cosmologies in the massive gravity theory with two dynamical metrics recently proposed in arXiv:1109.3515 and maintained to be ghost free. These solutions can be spatially open, closed, or flat, and at early times they are sourced by the perfect fluid, while the graviton mass typically manifests itself at late times by ...

Flavor phenomenology in general 5D warped spaces

We have considered a general 5D warped model with SM fields propagating in the bulk and computed explicit expressions for oblique and non-oblique electroweak observables as well as for flavor and C P violating effective four-fermion operators. We have compared the resulting lower bounds on the Kaluza Klein (KK) scale in the RS model and a recently proposed model with a metric ...

Phase structure of fuzzy black holes

Noncommutative deformations of the BTZ black holes are described by non- commutative cylinders. We study the scalar fields in this background. The spectrum is studied analytically and through numerical simulations we establish the existence of novel ‘stripe phases’. These are different from stripes on Moyal spaces and stable due to topo- logical obstruction.

\( {\Lambda_{{\overline {\text{MS}} }}} \) from the static potential for QCD with n f = 2 dynamical quark flavors

We determine \( {\Lambda_{{\overline {\text{MS}} }}} \) for QCD with n f = 2 dynamical quark flavors by fitting the \( Q\overline Q \) static potential known analytically in the perturbative regime up to terms of \( \mathcal{O}\left( {\alpha_s^4} \right) \) and \( \sim \alpha_s^4\ln \,{\alpha_s} \) to corresponding results obtained from lattice simulations. This has become ...

Critical points of maximal D = 8 gauged supergravities

We study the general deformations of maximal eight-dimensional supergravity by using the embedding tensor approach. The scalar potential induced by these gaugings is determined. Subsequently, by combining duality covariance arguments and algebraic geometry techniques, we find the complete set of critical points of the scalar potential. Remarkably, up to SO(2) × SO(3) rotations ...

Kinetic mixing of U(1)s in heterotic orbifolds

We study kinetic mixing between massless U(1) gauge symmetries in the bosonic formulation of heterotic orbifold compactifications. For non-prime Z N factorisable orbifolds, we find a simple expression of the mixing in terms of the properties of the \( \mathcal{N} \) =2subsectors,whichhelpsunderstandunderwhatconditionsmixingcanoccur. With this tool, we analyze Z6-II heterotic ...

A sufficient condition for de Sitter vacua in type IIB string theory

We derive a sufficient condition for realizing meta-stable de Sitter vacua with small positive cosmological constant within type IIB string theory flux compactifications with spontaneously broken supersymmetry. There are a number of ‘lamp post’ construc-tions of de Sitter vacua in type IIB string theory and supergravity. We show that one of them — the method of ‘Kähler uplifting’ ...

Top polarisation studies in H − t and W t production

The polarisation of top quarks produced in high energy processes can be a very sensitive probe of physics beyond the Standard Model. The kinematical distributions of the decay products of the top quark can provide clean information on the polarisation of the produced top and thus can probe new physics effects in the top quark sector. We study some of the recently proposed ...