Journal of High Energy Physics

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

List of Papers (Total 10,426)

Consistent on shell renormalisation of electroweakinos in the complex MSSM: LHC and LC predictions

We extend the formalism developed in ref. [53] for the renormalisation of the chargino-neutralino sector to the most general case of the MSSM with complex parameters. We show that products of imaginary parts arising from MSSM parameters and from absorptive parts of loop integrals can already contribute to predictions for physical observables at the one-loop level, and demonstrate...

Phenomenology of QCD threshold resummation for gluino pair production at NNLL

We examine the impact of threshold resummation for the inclusive hadronic production cross section of gluino pairs at next-to-next-to-leading-logarithmic accuracy, compared to the exact next-to-leading-order cross section and the next-to-next-to-leading-order approximation. Here, we apply formulas derived recently in the classical Mellin-space formalism. Moreover, we give the...

Determination of low-energy constants of Wilson chiral perturbation theory

By matching Wilson twisted mass lattice QCD determinations of pseudoscalar meson masses to Wilson Chiral Perturbation Theory we determine the low-energy constants \( W_6^{\prime } \), \( W_8^{\prime } \) and their linear combination c 2. We explore the dependence of these low-energy constants on the choice of the lattice action and on the number of dynamical flavours.

Momentum broadening in weakly coupled quark-gluon plasma (with a view to finding the quasiparticles within liquid quark-gluon plasma)

We calculate P (k ⊥), the probability distribution for an energetic parton that propagates for a distance L through a medium without radiating to pick up transverse momentum k ⊥, for a medium consisting of weakly coupled quark-gluon plasma. We use full or HTL self-energies in appropriate regimes, resumming each in order to find the leading large-L behavior. The jet quenching...

Measurement of D ± production in deep inelastic ep scattering with the ZEUS detector at HERA

Charm production in deep inelastic ep scattering was measured with the ZEUS detector using an integrated luminosity of 354 pb−1. Charm quarks were identified by reconstructing D ± mesons in the D ± → K ∓π±π± decay channel. Lifetime information was used to reduce combinatorial background substantially. Differential cross sections were measured in the kinematic region 5 < Q 2...

Lifting degeneracies in Higgs couplings using single top production in association with a Higgs boson

Current Higgs data show an ambiguity in the value of the Yukawa couplings to quarks and leptons. Not so much because of still large uncertainties in the measurements but as the result of several almost degenerate minima in the coupling profile likelihood function. To break these degeneracies, it is important to identify and measure processes where the Higgs coupling to fermions...

“L = R” - U(1) R lepton number at the LHC

We perform a detailed study of a variety of LHC signals in supersymmetric models where lepton number is promoted to an (approximate) U(1) R symmetry. Such a symmetry has interesting implications for naturalness, as well as flavor- and CP-violation, among others. Interestingly, it makes large sneutrino vacuum expectation values phenomenologically viable, so that a slepton doublet...

Multiple Higgs and vector boson production beyond the Standard Model

If the electroweak symmetry breaking is originated from a strongly coupled sector, as for instance in composite Higgs models, the Higgs boson couplings can deviate from their Standard Model values. In such cases, at sufficiently high energies there could occur an onset of multiple Higgs boson and longitudinally polarised electroweak gauge boson (V L ) production. We study the...

On the gravity dual of strongly coupled charged plasma

Locally asymptotically AdS solutions of Einstein equations coupled with a vector field with a weakly curved boundary metric are found within the fluid-gravity gradient expansion up to second order in gradients. This geometry is dual to 1 + 3 dimensional hydrodynamics with a conserved current in a weakly curved background. The causal structure of the bulk geometry is determined...

Parton distribution benchmarking with LHC data

AbstractWe present a detailed comparison of the most recent sets of NNLO PDFs from the ABM, CT, HERAPDF, MSTW and NNPDF collaborations. We compare parton distributions at low and high scales and parton luminosities relevant for LHC phenomenology. We study the PDF dependence of LHC benchmark inclusive cross sections and differential distributions for electroweak boson and jet...

A first top partner hunter’s guide

AbstractWe provide a systematic effective lagrangian description of the phenomenology of the lightest top-partners in composite Higgs models. Our construction is based on symmetry, on selection rules and on plausible dynamical assumptions. The structure of the resulting simplified models depends on the quantum numbers of the lightest top partner and of the operators involved in...

D3-instantons, mock theta series and twistors

AbstractThe D-instanton corrected hypermultiplet moduli space of type II string theory compactified on a Calabi-Yau threefold is known in the type IIA picture to be determined in terms of the generalized Donaldson-Thomas invariants, through a twistorial construction. At the same time, in the mirror type IIB picture, and in the limit where only D3-D1-D(-1)-instanton corrections...

Quantitative study of different forms of geometrical scaling in deep inelastic scattering at HERA

We use recently proposed method of ratios to assess the quality of geometrical scaling in deep inelastic scattering for different forms of the saturation scale. We consider original form of geometrical scaling (motivated by the Balitski-Kovchegov (BK) equation with fixed coupling) studied in more detail in our previous paper, and four new hypotheses: phenomenologically motivated...

Measurement of the X(3872) production cross section via decays to J/ψπ + π − in pp collisions at \( \sqrt{s}=7 \) TeV

The production of the X(3872) is studied in pp collisions at \( \sqrt{s}=7 \) TeV, using decays to J/ψπ + π −, where the J/ψ decays to two muons. The data were recorded by the CMS experiment and correspond to an integrated luminosity of 4.8 fb−1. The measurements are performed in a kinematic range in which the X(3872) candidates have a transverse momentum 10 < p T  < 50 GeV and...

The measurement of the Higgs self-coupling at the LHC: theoretical status

Now that the Higgs boson has been observed by the ATLAS and CMS experiments at the LHC, the next important step would be to measure accurately its properties to establish the details of the electroweak symmetry breaking mechanism. Among the measurements which need to be performed, the determination of the Higgs self-coupling in processes where the Higgs boson is produced in pairs...

5D maximally supersymmetric Yang-Mills in 4D superspace: applications

We reformulate 5D maximally supersymmetric Yang-Mills in 4D Superspace, for a manifold with boundaries. We emphasise certain features and conventions necessary to allow for supersymmetric model building applications. Finally we apply the holographic interpretation of a slice of AdS and show how to generate Dirac soft masses between external source fields, as well as kinetic...

Holographic models for undoped Weyl semimetals

We continue our recently proposed holographic description of single-particle correlation functions for four-dimensional chiral fermions with Lifshitz scaling at zero chemical potential, paying particular attention to the dynamical exponent z = 2. We present new results for the spectral densities and dispersion relations at non-zero momenta and temperature. In contrast to the...

Chiral symmetry and the Yang-Mills gradient flow

In the last few years, the Yang-Mills gradient flow was shown to be an attractive tool for non-perturbative studies of non-Abelian gauge theories. Here a simple extension of the flow to the quark fields in QCD is considered. As in the case of the puregauge gradient flow, the renormalizability of correlation functions involving local fields at positive flow times can be...

Type II superstring field theory: geometric approach and operadic description

We outline the construction of type II superstring field theory leading to a geometric and algebraic BV master equation, analogous to Zwiebach’s construction for the bosonic string. The construction uses the small Hilbert space. Elementary vertices of the non-polynomial action are described with the help of a properly formulated minimal area problem. They give rise to an infinite...

LHC constraints on M 1/2 and m 0 in the semi-constrained NMSSM

Constraints from searches for squarks and gluinos at the LHC at \( \sqrt{s}=8 \) TeV are applied to the parameter space of the NMSSM with universal squark/slepton and gaugino masses at the GUT scale, but allowing for non-universal soft Higgs mass parameters (the sNMSSM). We confine ourselves to regions of the parameter space compatible with a 125 GeV Higgs boson with diphoton...

Noncommutative field theories on \( \mathbb{R}_{\lambda}^3 \) : towards UV/IR mixing freedom

We consider the noncommutative space \( \mathbb{R}_{\lambda}^3 \), a deformation of the algebra of functions on \( {{\mathbb{R}}^3} \) which yields a “foliation” of \( {{\mathbb{R}}^3} \) into fuzzy spheres. We first construct a natural matrix base adapted to \( \mathbb{R}_{\lambda}^3 \). We then apply this general framework to the one-loop study of a two-parameter family of real...

Counting strings, wound and bound

We analyze zero mode counting problems for Dirac operators that find their origin in string theory backgrounds. A first class of quantum mechanical models for which we compute the number of ground states arises from a string winding an isometric direction in a geometry, taking into account its energy due to tension. Alternatively, the models arise from deforming marginal bound...