The European Physical Journal C

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

List of Papers (Total 3,079)

Non-minimal flavored \({S}_{3}\otimes {Z}_{2}\) left–right symmetric model

We propose a non-minimal left–right symmetric model with parity symmetry where the fermion mixings arise as a result of imposing an \(\mathbf{S}_{3}\otimes \mathbf{Z}_{2}\) flavor symmetry, and an extra \(\mathbf{Z}^{e}_{2}\) symmetry is considered in the lepton sector. Then the neutrino mass matrix possesses approximately the \(\mu \)–\(\tau \) symmetry. The breaking of the \(\mu ...

Measurement of D-meson production at mid-rapidity in pp collisions at \({\sqrt{s}=7}\) TeV

The production cross sections for prompt charmed mesons \(\mathrm{D^0}\), \(\mathrm{D^+}\), \(\mathrm{D^{*+}}\) and \(\mathrm{D_s^+}\) were measured at mid-rapidity in proton–proton collisions at a centre-of-mass energy \(\sqrt{s}=7~{\mathrm {TeV}}\) with the ALICE detector at the Large Hadron Collider (LHC). D mesons were reconstructed from their decays \(\mathrm{D}^0 \rightarrow ...

Geodesic flows in a charged black hole spacetime with quintessence

We investigate the evolution of timelike geodesic congruences, in the background of a charged black hole spacetime surrounded by quintessence. The Raychaudhuri equations for three kinematical quantities namely the expansion scalar, shear and rotation along the geodesic flows in such spacetime are obtained and solved numerically. We have also analysed both the weak and the strong ...

Effects of dark energy on the efficiency of charged AdS black holes as heat engines

In this paper, we study the heat engine where a charged AdS black hole surrounded by dark energy is the working substance and the mechanical work is done via the PdV term in the first law of black hole thermodynamics in the extended phase space. We first investigate the effects of a kind of dark energy (quintessence field in this paper) on the efficiency of the RN-AdS black holes ...

Ricci cubic gravity in d dimensions, gravitons and SAdS/Lifshitz black holes

A special class of higher curvature theories of gravity, Ricci cubic gravity (RCG), in general d dimensional space-time has been investigated in this paper. We have used two different approaches, the linearized equations of motion and the auxiliary field formalism to study the massive and massless graviton propagating modes of the AdS background. Using the auxiliary field ...

Thermal fluctuations in a hyperscaling-violation background

In this paper, we study the effect of thermal fluctuations on the thermodynamics of a black geometry with hyperscaling violation. These thermal fluctuations in the thermodynamics of this system are produced from quantum corrections of geometry describing this system. We discuss the stability of this system using specific heat and the entire Hessian matrix of the free energy. We ...

Detection of relic gravitational waves in thermal case by using Adv.LIGO data of GW150914

The thermal spectrum of relic gravitational waves enhances the usual spectrum. Our analysis shows that there exist some chances for detection of the thermal spectrum in addition to the usual spectrum by comparison with sensitivity of Adv.LIGO of GW150914 and detector based on the maser light. The behavior of the inflation and reheating stages are often known as power law expansion ...

f(R) gravity solutions for evolving wormholes

The scalar–tensor f(R) theory of gravity is considered in the framework of a simple inhomogeneous space-time model. In this research we use the reconstruction technique to look for possible evolving wormhole solutions within viable f(R) gravity formalism. These f(R) models are then constrained so that they are consistent with existing experimental data. Energy conditions related to ...

Generalized spheroidal spacetimes in 5-D Einstein–Maxwell–Gauss–Bonnet gravity

The field equations for static EGBM gravity are obtained and transformed to an equivalent form through a coordinate redefinition. A form for one of the metric potentials that generalizes the spheroidal ansatz of Vaidya–Tikekar superdense stars and additionally prescribing the electric field intensity yields viable solutions. Some special cases of the general solution are considered ...

Disentangling weak and strong interactions in \(B\rightarrow K^{*}(\rightarrow K\pi )\pi \) Dalitz-plot analyses

Dalitz-plot analyses of \(B\rightarrow K\pi \pi \) decays provide direct access to decay amplitudes, and thereby weak and strong phases can be disentangled by resolving the interference patterns in phase space between intermediate resonant states. A phenomenological isospin analysis of \(B\rightarrow K^*(\rightarrow K\pi )\pi \) decay amplitudes is presented exploiting available ...

On-shell neutral Higgs bosons in the NMSSM with complex parameters

The Next-to-Minimal Supersymmetric Standard model (NMSSM) appears as an interesting candidate for the interpretation of the Higgs measurement at the LHC and as a rich framework embedding physics beyond the Standard Model. We consider the renormalization of the Higgs sector of this model in its \(\mathcal{CP}\)-violating version, and propose a renormalization scheme for the ...

Two Higgs bosons near 125 GeV in the NMSSM: beyond the narrow width approximation

In the next-to-minimal supersymmetric (NMS) Standard Model (SM), it is possible for either one of the additional singlet-like scalar and pseudoscalar Higgs bosons to be almost degenerate in mass with the \(\sim \) \(125\) GeV SM-like Higgs state. In the real NMSSM (rNMSSM), when the mass difference between two scalar states is comparable to their individual total decay widths, the ...

The projected background for the CUORE experiment

The Cryogenic Underground Observatory for Rare Events (CUORE) is designed to search for neutrinoless double beta decay of \(^{130}\)Te with an array of 988 TeO\(_2\) bolometers operating at temperatures around 10 mK. The experiment is currently being commissioned in Hall A of Laboratori Nazionali del Gran Sasso, Italy. The goal of CUORE is to reach a 90% C.L. exclusion sensitivity ...

Non-minimal derivative coupling scalar field and bulk viscous dark energy

Inspired by thermodynamical dissipative phenomena, we consider bulk viscosity for dark fluid in a spatially flat two-component Universe. Our viscous dark energy model represents phantom-crossing which avoids big-rip singularity. We propose a non-minimal derivative coupling scalar field with zero potential leading to accelerated expansion of the Universe in the framework of bulk ...

Neutrino induced vorticity, Alfvén waves and the normal modes

We consider a plasma consisting of electrons and ions in the presence of a background neutrino gas and develop the magnetohydrodynamic equations for the system. We show that the electron neutrino interaction can induce vorticity in the plasma even in the absence of any electromagnetic perturbations if the background neutrino density is left–right asymmetric. This induced vorticity ...

On the gravitational seesaw in higher-derivative gravity

Local gravitational theories with more than four derivatives are superrenormalizable. They also may be unitary in the Lee–Wick sense. Thus it is relevant to study the low-energy properties of these theories, especially to identify observables which might be useful for experimental detection of higher derivatives. Using an analogy with the neutrino physics, we explore the ...

Energy conditions of non-singular black hole spacetimes in conformal gravity

Conformal gravity can elegantly solve the problem of spacetime singularities present in Einstein’s gravity. For every physical spacetime, there is an infinite family of conformally equivalent singularity-free metrics. In the unbroken phase, every non-singular metric is equivalent and can be used to infer the physical properties of the spacetime. In the broken phase, a Higgs-like ...

Heat engines for dilatonic Born–Infeld black holes

In the context of dilaton coupled Einstein gravity with a negative cosmological constant and a Born–Infeld field, we study heat engines where a charged black hole is the working substance. Using the existence of a notion of thermodynamic mass and volume (which depend on the dilaton coupling), the mechanical work takes place via the pdV terms present in the first law of extended ...

Top quark electroweak couplings at future lepton colliders

We perform a comparative study of the reach of future \(e^+e^-\) collider options for the scale of non-resonant new physics effects in the top quark sector, phrased in the language of higher-dimensional operators. Our focus is on the electroweak top quark pair production process \(e^+e^- \rightarrow Z^*/\gamma \rightarrow t\bar{t} \), and we study benchmark scenarios at the ILC and ...

What is the scale of new physics behind the B-flavour anomalies?

Motivated by the recent hints of lepton flavour non-universality in B-meson semi-leptonic decays, we study the constraints of perturbative unitarity on the new physics interpretation of the anomalies in \(b \rightarrow c \ell \bar{\nu }\) and \(b \rightarrow s \ell \bar{\ell }\) transitions. Within an effective field theory approach we find that \(2 \rightarrow 2\) fermion ...

f(R) constant-roll inflation

The previously introduced class of two-parametric phenomenological inflationary models in general relativity in which the slow-roll assumption is replaced by the more general, constant-roll condition is generalized to the case of f(R) gravity. A simple constant-roll condition is defined in the original Jordan frame, and exact expressions for a scalaron potential in the Einstein ...

Gravitational perfect fluid collapse in Gauss–Bonnet gravity

The Einstein Gauss–Bonnet theory of gravity is the low-energy limit of heterotic super-symmetric string theory. This paper deals with gravitational collapse of a perfect fluid in Einstein–Gauss–Bonnet gravity by considering the Lemaitre–Tolman–Bondi metric. For this purpose, the closed form of the exact solution of the equations of motion has been determined by using the ...

Cosmic structure sizes in generic dark energy models

The maximum allowable size of a spherical cosmic structure as a function of its mass is determined by the maximum turn around radius \(R_\mathrm{TA,max}\), the distance from its center where the attraction on a radial test particle due to the spherical mass is balanced with the repulsion due to the ambient dark energy. In this work, we extend the existing results in several ...