The European Physical Journal C

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

List of Papers (Total 3,408)

Evidence of ghost suppression in gluon mass scale dynamics

In this work we study the impact that the ghost sector of pure Yang–Mills theories may have on the generation of a dynamical gauge boson mass scale, which hinges on the appearance of massless poles in the fundamental vertices of the theory, and the subsequent realization of the well-known Schwinger mechanism. The process responsible for the formation of such structures is itself ...

New constraints on the 3-3-1 model with right-handed neutrinos

In the framework of a 3-3-1 model with right-handed neutrinos and three scalar triplets we consider different spontaneous symmetry breaking patterns seeking for a non-linear realization of accidental symmetries of the model, which will produce physical Nambu–Goldstone (NG) bosons in the neutral scalar spectrum. We make a detailed study of the safety of the model concerning the NG ...

Measurement of $$\tau $$ polarisation in $$Z/\gamma ^{*}\rightarrow \tau \tau $$Z/γ∗→ decays in proton–proton collisions at $$\sqrt{s}=8$$s=8 TeV with the ATLAS detector

This paper presents a measurement of the polarisation of \(\tau \) leptons produced in \(Z/\gamma ^{*}\rightarrow \tau \tau \) decays which is performed with a dataset of proton—proton collisions at \(\sqrt{s}=8\) TeV, corresponding to an integrated luminosity of 20.2 fb\(^{-1}\) recorded with the ATLAS detector at the LHC in 2012. The \(Z/\gamma ^{*}\rightarrow \tau \tau \) decays ...

Higher-curvature corrections to holographic entanglement with momentum dissipation

We study the effects of Gauss–Bonnet corrections on some nonlocal probes (entanglement entropy, n-partite information and Wilson loop) in the holographic model with momentum relaxation. Higher-curvature terms as well as scalar fields make in fact nontrivial corrections to the coefficient of the universal term in entanglement entropy. We use holographic methods to study such ...

Critical behavior and phase transition of dilaton black holes with nonlinear electrodynamics

In this paper, we take into account the dilaton black hole solutions of Einstein gravity in the presence of logarithmic and exponential forms of nonlinear electrodynamics. First of all, we consider the cosmological constant and nonlinear parameter as thermodynamic quantities which can vary. We obtain thermodynamic quantities of the system such as pressure, temperature and Gibbs ...

Interference effect as resonance killer of newly observed charmoniumlike states <Emphasis Type=

In this letter, we decode the newly observed charmoniumlike states, Y(4320) and Y(4390), by introducing interference effect between \(\psi (4160)\) and \(\psi (4415)\), which plays a role of resonance killer for Y(4320) and Y(4390). It means that two newly reported charmoniumlike states are not genuine resonances, according to which we can naturally explain why two well-established ...

Direct top-quark decay width measurement in the $$\mathbf {\varvec{t\bar{t}}}$$ lepton+jets channel at $$\sqrt{s}=8~\text {TeV}$$s=8TeV with the ATLAS experiment

This paper presents a direct measurement of the decay width of the top quark using \(t\bar{t}\) events in the lepton+jets final state. The data sample was collected by the ATLAS detector at the LHC in proton–proton collisions at a centre-of-mass energy of 8 TeV and corresponds to an integrated luminosity of 20.2 fb\(^{-1}\). The decay width of the top quark is measured using a ...

Unbinned model-independent measurements with coherent admixtures of multibody neutral <Emphasis Type=

Various studies of Standard Model parameters involve measuring the properties of a coherent admixture of \({D} ^0\) and \({\overline{D}{}} {}^0\) states. A typical example is the determination of the Unitarity Triangle angle \(\gamma \) in the decays \(B\rightarrow DK\), \(D\rightarrow {{K} ^0_\mathrm{\scriptscriptstyle S}} {{\pi } ^+} {{\pi } ^-} \). A model-independent approach ...

On the hadron mass decomposition

We argue that the standard decompositions of the hadron mass overlook pressure effects, and hence should be interpreted with great care. Based on the semiclassical picture, we propose a new decomposition that properly accounts for these pressure effects. Because of Lorentz covariance, we stress that the hadron mass decomposition automatically comes along with a stability ...

“Spin-dependent” $$\varvec{\mu \rightarrow e}$$ conversion on light nuclei

The experimental sensitivity to \(\mu \rightarrow e\) conversion will improve by four or more orders of magnitude in coming years, making it interesting to consider the “spin-dependent” (SD) contribution to the rate. This process does not benefit from the atomic-number-squared enhancement of the spin-independent (SI) contribution, but probes different operators. We give details of ...

Stab le exponentia l cosmo logica l so lutions with 3- and l-dimensiona l factor spaces in the Einstein–Gauss–Bonnet mode l with a $$\Lambda $$-term

A D-dimensional gravitational model with a Gauss–Bonnet term and the cosmological term \(\Lambda \) is studied. We assume the metrics to be diagonal cosmological ones. For certain fine-tuned \(\Lambda \), we find a class of solutions with exponential time dependence of two scale factors, governed by two Hubble-like parameters \(H >0\) and h, corresponding to factor spaces of ...

The DKP oscillator with a linear interaction in the cosmic string space-time

We study the relativistic quantum dynamics of a DKP oscillator field subject to a linear interaction in cosmic string space-time in order to better understand the effects of gravitational fields produced by topological defects on the scalar field. We obtain the solution of DKP oscillator in the cosmic string background. Also, we solve it with an ansatz in the presence of a linear ...

Search for heavy neutrino in $$K^{+} \rightarrow \mu ^{+} \nu _{H}$$ decay

A high statistics data sample of the \(K^{+}\rightarrow \mu ^{+}\nu _{\mu }\) decay was accumulated by the OKA experiment in 2012. The missing mass analysis was performed to search for the decay channel \(K^{+}\rightarrow \mu ^{+}\nu _{H}\) with a hypothetic stable heavy neutrino in the final state. The obtained missing mass spectrum does not show peaks that could be attributed to ...

The Pandora multi-algorithm approach to automated pattern recognition of cosmic-ray muon and neutrino events in the MicroBooNE detector

The development and operation of liquid-argon time-projection chambers for neutrino physics has created a need for new approaches to pattern recognition in order to fully exploit the imaging capabilities offered by this technology. Whereas the human brain can excel at identifying features in the recorded events, it is a significant challenge to develop an automated, algorithmic ...

Investigation of DKP equation for spin-zero system in the presence of Gödel-type background space-time

This paper contains a discussion of a relativistic spin-0 system in the presence of a Gödel-type background space-time. The Duffin–Kemmer–Petiau (DKP) equation in the presence of a Gödel-type background space-time is studied in detail. After a derivation of the final form of this equation in the considered framework, free spin-0 particles have been studied.

Quantum spreading of a self-gravitating wave-packet in singularity free gravity

In this paper we will study for the first time how the wave-packet of a self-gravitating meso-scopic system spreads in theories beyond Einstein’s general relativity. In particular, we will consider a ghost-free infinite derivative gravity, which resolves the 1 / r singularity in the potential – such that the gradient of the potential vanishes within the scale of non-locality. We ...

What’s the point? Hole-ography in Poincaré AdS

In the context of the AdS/CFT correspondence, we study bulk reconstruction of the Poincaré wedge of AdS\(_3\) via hole-ography, i.e., in terms of differential entropy of the dual CFT\(_2\). Previous work had considered the reconstruction of closed or open spacelike curves in global AdS, and of infinitely extended spacelike curves in Poincaré AdS that are subject to a periodicity ...

Binary black hole in a double magnetic monopole field

Ambient magnetic fields are thought to play a critical role in black hole jet formation. Furthermore, dual electromagnetic signals could be produced during the inspiral and merger of binary black hole systems. In this paper, we derive the exact solution for the electromagnetic field occurring when a static, axisymmetric binary black hole system is placed in the field of two ...

Thermodynamics and relativistic kinetic theory for <Emphasis Type=

The thermodynamics and covariant kinetic theory are elaborately investigated in a non-extensive environment considering the non-extensive generalization of Bose–Einstein (BE) and Fermi–Dirac (FD) statistics. Starting with Tsallis’ entropy formula, the fundamental principles of thermostatistics are established for a grand canonical system having q-generalized BE/FD degrees of ...

Weak decays of doubly heavy baryons: multi-body decay channels

The newly-discovered \(\Xi _{cc}^{++}\) decays into the \( \Lambda _{c}^+ K^-\pi ^+\pi ^+\), but the experimental data has indicated that this decay is not saturated by any two-body intermediate state. In this work, we analyze the multi-body weak decays of doubly heavy baryons \(\Xi _{cc}\), \(\Omega _{cc}\), \(\Xi _{bc}\), \(\Omega _{bc}\), \(\Xi _{bb}\) and \(\Omega _{bb}\), in ...

Interferometry correlations in central p+Pb collisions

We present results on interferometry correlations for pions emitted in central p+Pb collisions at \(\sqrt{s_{NN}}=5.02~\hbox {TeV}\) in a \(3+1\)-dimensional viscous hydrodynamic model with initial conditions from the Glauber Monte Carlo model. The correlation function is calculated as a function of the pion pair rapidity. The extracted interferometry radii show a weak rapidity ...

Criticality in third order lovelock gravity and butterfly effect

We study third order Lovelock Gravity in \(D=7\) at the critical point which three (A)dS vacua degenerate into one. We see there is not propagating graviton at the critical point. And also we compute the butterfly velocity for this theory at the critical point by considering the shock wave solutions near horizon, this is important to note that although there is no propagating ...

Wormholes in $$ R^2$$ -gravity within the f( R, T) formalism

We propose, as a novelty in the literature, the modeling of wormholes within a particular case of f(R, T) gravity, namely \(f(R,T)=R+\alpha R^{2}+\lambda T\), with R and T being the Ricci scalar and trace of the energy-momentum tensor, respectively, while \(\alpha \) and \(\lambda \) are constants. Although such a functional form application can be found in the literature, those ...

Radiating star with a time-dependent Karmarkar condition

In this paper we employ the Karmarkar condition (Proc Indian Acad Sci A 27:56, 1948) to model a spherically symmetric radiating star undergoing dissipative gravitational collapse in the form of a radial heat flux. A particular solution of the boundary condition renders the Karmarkar condition independent of time which allows us to fully specify the spatial behaviour of the ...

Anisotropic charged physical models with generalized polytropic equation of state

In this paper, we found the exact solutions of Einstein–Maxwell equations with generalized polytropic equation of state (GPEoS). For this, we consider spherically symmetric object with charged anisotropic matter distribution. We rewrite the field equations into simple form through transformation introduced by Durgapal (Phys Rev D 27:328, 1983) and solve these equations ...