The European Physical Journal C

http://link.springer.com/journal/10052

List of Papers (Total 3,658)

Momentum dissipation and holographic transport without self-duality

We explore the response of the momentum dissipation introduced by spatial linear axionic fields in a holographic model without self-duality, which is broke by Weyl tensor coupling to Maxwell field. It is found that for the positive Weyl coupling parameter \(\gamma >0\), the momentum dissipation, characterized by parameter \({\hat{\alpha }}\), drives an incoherent metallic state...

A note on thin-shell wormholes with charge in F(R)-gravity

In their recent work (Eiroa and Aguirre in Eur Phys J C 76:132, 2016), Eiroa and Aguirre introduced thin-shell wormholes in \(F\left( R\right) =R+\alpha R^{2}\)-gravity coupled with the Maxwell electromagnetic field. Here in this note we shall address an interesting feature of their results which has been missed. It will be shown that thin-shell wormhole can not be formed in the...

Non-perturbative renormalisation and running of BSM four-quark operators in \(N_\mathrm {\scriptstyle f}=2\) QCD

We perform a non-perturbative study of the scale-dependent renormalisation factors of a complete set of dimension-six four-fermion operators without power subtractions. The renormalisation-group (RG) running is determined in the continuum limit for a specific Schrödinger Functional (SF) renormalisation scheme in the framework of lattice QCD with two dynamical flavours (\(N_...

Discovery potential for directional Dark Matter detection with nuclear emulsions

Direct Dark Matter searches are nowadays one of the most fervid research topics with many experimental efforts devoted to the search for nuclear recoils induced by the scattering of Weakly Interactive Massive Particles (WIMPs). Detectors able to reconstruct the direction of the nucleus recoiling against the scattering WIMP are opening a new frontier to possibly extend Dark Matter...

Quasilocal first law of black hole dynamics from local Lorentz transformations

Quasilocal formulations of black hole are of immense importance since they reveal the essential and minimal assumptions required for a consistent description of black hole horizon, without relying on the asymptotic boundary conditions on fields. Using the quasilocal formulation of Isolated Horizons, we construct the Hamiltonian charges corresponding to local Lorentz...

Holevo bound of entropic uncertainty in Schwarzschild spacetime

For a pair of incompatible quantum measurements, the total uncertainty can be bounded by a state-independent constant. However, such a bound can be violated if the quantum system is entangled with another quantum system (called memory); the quantum correlation between the systems can reduce the measurement uncertainty. On the other hand, in a curved spacetime, the presence of the...

Mass and angular momentum of black holes in 3D gravity theories with first order formalism

We apply the Wald formalism to obtain masses and angular momenta of black holes in three dimensional gravity theories using the first order formalism. Wald formalism suggests that the entropy of a black hole can be defined by an integration of a conserved charge on the bifurcation horizon, and mass and angular momentum of a black hole as an integration of some charge variation...

Stratified scalar field theories of gravitation with self-energy term and effective particle Lagrangian

We construct a general stratified scalar theory of gravitation from a field equation that accounts for the self-interaction of the field and a particle Lagrangian, and calculate its post-Newtonian parameters. Using this general framework, we analyze several specific scalar theories of gravitation and check their predictions for the solar system post-Newtonian effects.

Measurement of prompt and nonprompt charmonium suppression in \(\text {PbPb}\) collisions at 5.02 \(\,\text {Te}\text {V}\)

The nuclear modification factors of \({\mathrm {J}/\psi }\) and \(\psi \text {(2S)}\) mesons are measured in \(\text {PbPb}\) collisions at a centre-of-mass energy per nucleon pair of \(\sqrt{\smash [b]{s_{_{\text {NN}}}}} = 5.02\,\text {Te}\text {V} \). The analysis is based on \(\text {PbPb}\) and \(\mathrm {p}\mathrm {p}\) data samples collected by CMS at the LHC in 2015...

Precise determination of \(\alpha _{S}(M_Z)\) from a global fit of energy–energy correlation to NNLO+NNLL predictions

We present a comparison of the computation of energy–energy correlation in \(e^{+}e^{-}\) collisions in the back-to-back region at next-to-next-to-leading logarithmic accuracy matched with the next-to-next-to-leading order perturbative prediction to LEP, PEP, PETRA, SLC and TRISTAN data. With these predictions we perform an extraction of the strong coupling constant taking into...

Analysis of b quark pair production signal from neutral 2HDM Higgs bosons at future linear colliders

In this paper, the b quark pair production events are analyzed as a source of neutral Higgs bosons of the two Higgs doublet model type I at linear colliders. The production mechanism is \(e^{+}e^{-} \rightarrow Z^{(*)} \rightarrow HA \rightarrow b{\bar{b}}b{\bar{b}}\) assuming a fully hadronic final state. The analysis aim is to identify both CP-even and CP-odd Higgs bosons in...

Dark matter direct detection of a fermionic singlet at one loop

The strong direct detection limits could be pointing to dark matter – nucleus scattering at loop level. We study in detail the prototype example of an electroweak singlet (Dirac or Majorana) dark matter fermion coupled to an extended dark sector, which is composed of a new fermion and a new scalar. Given the strong limits on colored particles from direct and indirect searches we...

Gaussian processes reconstruction of dark energy from observational data

In the present paper, we investigate the dark energy equation of state using the Gaussian processes analysis method, without confining a particular parametrization. The reconstruction is carried out by adopting the background data including supernova and Hubble parameter, and perturbation data from the growth rate. It suggests that the background and perturbation data both...

Some results on a black hole with a global monopole in Poincaré gravity

The aim of this work is to study the thermodynamics and spin current of a system corresponding to a black hole containing a global monopole in the context of Poincaré gravity theory which is an extension of general relativity, in the sense that the intrinsic angular momentum of matter is also a source of gravitational interaction. Thus, in this work we find the solution...

Palatini formulation of f(R, T) gravity theory, and its cosmological implications

We consider the Palatini formulation of f(R, T) gravity theory, in which a non-minimal coupling between the Ricci scalar and the trace of the energy-momentum tensor is introduced, by considering the metric and the affine connection as independent field variables. The field equations and the equations of motion for massive test particles are derived, and we show that the...

On stability of a neutron star system in Palatini gravity

We formulate the generalized Tolman–Oppenheimer–Volkoff equations for the \(f(\hat{R})\) Palatini gravity in the case of static and spherical symmetric geometry. We also show that a neutron star can be a stable system independently of the form of the functional \(f(\hat{R})\).

Non-perturbative to perturbative QCD via the FFBRST

Recently a new type of quadratic gauge was introduced in QCD in which the degrees of freedom are suggestive of a phase of abelian dominance. In its simplest form it is also free of Gribov ambiguity. However this gauge is not suitable for usual perturbation theory. The finite field dependent BRST (FFBRST) transformation is a method established to interrelate generating functionals...

The minimal axion minimal linear \(\sigma \) model

The minimal SO(5) / SO(4) linear \(\sigma \) model is extended including an additional complex scalar field, singlet under the global SO(5) and the Standard Model gauge symmetries. The presence of this scalar field creates the conditions to generate an axion à la KSVZ, providing a solution to the strong CP problem, or an axion-like-particle. Different choices for the PQ charges...

White dwarfs with a surface electrical charge distribution: equilibrium and stability

The equilibrium configuration and the radial stability of white dwarfs composed of charged perfect fluid are investigated. These cases are analyzed through the results obtained from the solution of the hydrostatic equilibrium equation. We regard that the fluid pressure and the fluid energy density follow the relation of a fully degenerate electron gas. For the electric charge...

Stephani cosmology: entropically viable but observationally challenged

Inhomogeneous cosmological models such as the Stephani universes could, in principle, provide an explanation for the observed accelerated expansion of the Universe. Working with a concrete, popular model of the Stephani cosmology – the Stephani-Da̧browski model, we found that it is entropically viable. We also comment on the energy conditions and the two-sheeted geometry of the...

The cosmological nature of the dark Universe

This paper deals with the cancellation mechanism, which identifies the energy density of space-time expansion in an empty universe with the zero-point energy density and avoids the scale discrepancy with the observed energy density (cosmological constant problem). Using an intrinsic degree of freedom which describes the coupling of a variable cosmological term \(\varLambda...

Search for a new heavy gauge-boson resonance decaying into a lepton and missing transverse momentum in 36 fb \(^{-1}\) of pp collisions at \(\sqrt{s} = 13\) TeV with the ATLAS experiment

The results of a search for new heavy \(W^\prime \) bosons decaying to an electron or muon and a neutrino using proton–proton collision data at a centre-of-mass energy of \(\sqrt{s}~=~13\) TeV are presented. The dataset was collected in 2015 and 2016 by the ATLAS experiment at the Large Hadron Collider and corresponds to an integrated luminosity of 36.1 \(\text{ fb }^{-1}\). As...

Bouncing cosmological solutions from \(f(\mathsf{R,T})\) gravity

In this work we study classical bouncing solutions in the context of \(f(\mathsf{R},\mathsf{T})=\mathsf{R}+h(\mathsf{T})\) gravity in a flat FLRW background using a perfect fluid as the only matter content. Our investigation is based on introducing an effective fluid through defining effective energy density and pressure; we call this reformulation as the “effective picture...

Scalar pair production in a magnetic field in de Sitter universe

The production of scalar particles by the dipole magnetic field in de Sitter expanding universe is analyzed. The amplitude and probability of transition are computed using perturbative methods. A graphical study of the transition probability is performed obtaining that the rate of pair production is important in the early universe. Our results prove that in the process of pair...

Analysis of the structure of \(\Xi (1690)\) through its decays

The mass and pole residue of the first orbitally and radially excited \( \Xi \) state as well as the ground state residue are calculated by means of the two-point QCD sum rules. Using the obtained results for the spectroscopic parameters, the strong coupling constants relevant to the decays \(\Xi (1690)\rightarrow \Sigma K\) and \(\Xi (1690) \rightarrow \Lambda K\) are calculated...