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Bayesian comparison of interacting modified holographic Ricci dark energy scenarios Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-15 Antonella Cid, Carlos Rodriguez-Benites, Mauricio Cataldo, Gonzalo Casanova
We perform a Bayesian model selection analysis for interacting scenarios of dark matter and modified holographic Ricci dark energy (MHRDE) with linear interacting terms. We use a combination of some of the latest cosmological data such as type Ia supernovae, cosmic chronometers, the local value of the Hubble constant, baryon acoustic oscillations measurements and cosmic microwave background through
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Van der Meer scan luminosity measurement and beam–beam correction Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-15 Vladislav Balagura
The main method for calibrating the luminosity at Large Hadron Collider (LHC) is van der Meer scan where the beams are swept transversely across each other. This beautiful method was invented in 1968. Despite the honourable age, it remains the preferable tool at hadron colliders. It delivers the lowest calibration systematics, which still often dominates the overall luminosity uncertainty at LHC experiments
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$$B_{(s)}$$ B ( s ) to light tensor meson form factors via LCSR in HQEFT with applications to semileptonic decays Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-15 Ya-Bing Zuo, Chong-Xing Yue, Bo Yu, Ying-Hui Kou, Yan Chen, Wen Ling
In the present work, the form factors of \(B_{(s)}\) to light P-wave tensor mesons (\(a_2(1320)\), \(K^*_2(1430)\), \(f_2(1270)\), \(f^\prime _2(1525)\)) are calculated via the light cone sum rules (LCSR) in the framework of heavy quark effective field theory (HQEFT). Firstly, the expressions of form factors in terms of the light cone distribution amplitudes (DAs) of tensor mesons are derived via the
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Neutrino masses and Hubble tension via a Majoron in MFV Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-15 Fernando Arias-Aragón, Enrique Fernández-Martínez, Manuel González-López, Luca Merlo
The recent tension between local and early measurements of the Hubble constant can be explained in a particle physics context. A mechanism is presented where this tension is alleviated due to the presence of a Majoron, arising from the spontaneous breaking of Lepton Number. The lightness of the active neutrinos is consistently explained. Moreover, this mechanism is shown to be embeddable in the minimal
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Erratum to: Higgs boson production cross-section measurements and their EFT interpretation in the $$4\ell $$ 4 ℓ decay channel at $$\sqrt{s}=$$ s = 13 TeV with the ATLAS detector Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-15 G. Aad, B. Abbott, D. C. Abbott, A. Abed Abud, K. Abeling, D. K. Abhayasinghe, S. H. Abidi, O. S. AbouZeid, N. L. Abraham, H. Abramowicz, H. Abreu, Y. Abulaiti, B. S. Acharya, B. Achkar, L. Adam, C. Adam Bourdarios, L. Adamczyk, L. Adamek, J. Adelman, M. Adersberger, A. Adiguzel, S. Adorni, T. Adye, A. A. Affolder, Y. Afik, C. Agapopoulou, M. N. Agaras, A. Aggarwal, C. Agheorghiesei, J. A. Aguilar-Saavedra
In the published HTML version of this article, the affiliations of the authors of the National Research Nuclear University MEPhI, Moscow, Russia were unfortunately marked incorrectly.
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Finding new physics without learning about it: anomaly detection as a tool for searches at colliders Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-15 M. Crispim Romão, N. F. Castro, R. Pedro
In this paper we propose a new strategy, based on anomaly detection methods, to search for new physics phenomena at colliders independently of the details of such new events. For this purpose, machine learning techniques are trained using Standard Model events, with the corresponding outputs being sensitive to physics beyond it. We explore three novel AD methods in HEP: Isolation Forest, Histogram-Based
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Quasi-geodesics in relativistic gravity Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-13 Valerio Faraoni, Geneviève Vachon
A four-force parallel to the trajectory of a massive particle can always be eliminated by going to an affine parametrization, but the affine parameter is different from the proper time. The main application is to cosmology, in which elements of the cosmic fluid are subject to a pressure gradient parallel to their four-velocities. Natural implementations of parallel four-forces occur when the particle
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Deciphering the recently discovered tetraquark candidates around 6.9 GeV Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-13 Jacob Sonnenschein, Dorin Weissman
Recently a novel hadronic state of mass 6.9 GeV, that decays mainly to a pair of charmonia, was observed in LHCb. The data also reveals a broader structure centered around 6490 MeV and suggests another unconfirmed resonance centered at around 7240 MeV, very near to the threshold of two doubly charmed \(\Xi _{cc}\) baryons. We argue in this note that these exotic hadrons are genuine tetraquarks and
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Phase separation and exotic vortex phases in a two-species holographic superfluid Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-13 Wei-Can Yang, Chuan-Yin Xia, Hua-Bi Zeng, Hai-Qing Zhang
At finite temperature, the stable equilibrium states of coupled two-component Bose Einstein condensations (BECs) with the same conformal mass in both non-rotating and rotating condition can be obtained by studying its real dynamics via holography. The equilibrium state is the state where the free energy reaches the minimum and does not change any more. In the case of no rotation, the spatial phase
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Thick brane structures in generalized hybrid metric-Palatini gravity Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-13 João Luís Rosa, D. A. Ferreira, Dionisio Bazeia, Francisco S. N. Lobo
In this work, we study 5-dimensional braneworld scenarios in the scalar-tensor representation of the generalized hybrid metric-Palatini gravitational theory. We start by considering a model for a brane supported purely by the gravitational scalar fields of the theory and then consider other distinct cases where the models are also supported by an additional matter scalar field. We investigate the stability
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Classical and quantum $$(2+1)$$ ( 2 + 1 ) -dimensional spatially homogeneous string cosmology Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-13 F. Naderi, A. Rezaei-Aghdam
We introduce three families of classical and quantum solutions to the leading order of string effective action on spatially homogeneous \((2+1)\)-dimensional space-times with the sources given by the contributions of dilaton, antisymmetric gauge B-field, and central charge deficit term \(\varLambda \). At the quantum level, solutions of Wheeler–DeWitt equations have been enriched by considering the
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Thermodynamical phases in a PNJL model at zero temperature Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-13 O. A. Mattos, T. Frederico, O. Lourenço
The confinement/deconfinement transition described the Polyakov–Nambu–Jona–Lasinio (PNJL) model is extended to be operative at zero temperature regime. In this study, the scalar and vector channel interaction strengths of the original PNJL model are modified by introducing a dependence on the traced Polyakov loop. In such a way the effective interactions depend on the quark phase and in turn provides
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Canonical analysis of geometrical action for Dp-brane Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-13 Josef Klusoň
In this short note we perform canonical analysis of geometrical action for Dp-brane. We also discuss tachyon condensation in case of the geometrical action for unstable D(p+1)-brane.
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Polarized parton distribution functions: parametrization and transverse momentum dependence Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-12 H. Nematollahi, P. Abolhadi, S. Atashbar, A. Mirjalili, M. M. Yazdanpanah
We extract the polarized parton distribution functions (PPDFs) of proton. To this end we do a global analysis on recent and up-to-dated experimental data of polarized nucleon and deuteron structure functions at the NLO accuracy of perturbative QCD. We use the Jacobi polynomials expansion technique to do the required analyses. To achieve a more realistic estimation of the PPDFs and observable uncertainties
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On perturbation theory and critical exponents for self-similar systems Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-12 Ehsan Hatefi, Adrien Kuntz
Gravitational critical collapse in the Einstein-axion-dilaton system is known to lead to continuous self-similar solutions characterized by the Choptuik critical exponent \(\gamma \). We complete the existing literature on the subject by computing the linear perturbation equations in the case where the axion-dilaton system assumes a parabolic form. Next, we solve the perturbation equations in a newly
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Structure scalars and their evolution for massive objects in f ( R ) gravity Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-12 M. Z. Bhatti, Z. Yousaf, Z. Tariq
In this manuscript, the Riemann tensor is split orthogonally to get five scalar functions known as structure scalars which have significance to gain insight into the composition and structure of spherically symmetric self-gravitating objects. Certain stellar equations are then evaluated to gather information about physical characteristics of such astrophysical objects. These stellar equations are further
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Probing neutron-hidden neutron transitions with the MURMUR experiment Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-12 Coraline Stasser, Guy Terwagne, Jacob Lamblin, Olivier Méplan, Guillaume Pignol, Bernard Coupé, Silva Kalcheva, Steven Van Dyck, Michaël Sarrazin
MURMUR is a new passing-through-walls neutron experiment designed to constrain neutron-hidden neutron transitions allowed in the context of braneworld scenarios or mirror matter models. A nuclear reactor can act as a source of hidden neutrons, such that neutrons travel through a hidden world or sector. Hidden neutrons can propagate out of the nuclear core and far beyond the biological shielding. However
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Model-independent constraints on cosmic curvature: implication from the future space gravitational-wave antenna DECIGO Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-11 Xiaogang Zheng, Shuo Cao, Yuting Liu, Marek Biesiada, Tonghua Liu, Shuaibo Geng, Yujie Lian, Wuzheng Guo
In order to estimate cosmic curvature from cosmological probes like standard candles, one has to measure the luminosity distance \(D_L(z)\), its derivative with respect to redshift \(D'_L(z)\) and the expansion rate H(z) at the same redshift. In this paper, we study how such idea could be implemented with future generation of space-based DECi-hertz Interferometer Gravitational-wave Observatory (DECIGO)
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Search for phenomena beyond the Standard Model in events with large b -jet multiplicity using the ATLAS detector at the LHC Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-11 G. Aad, B. Abbott, D. C. Abbott, A. Abed Abud, K. Abeling, D. K. Abhayasinghe, S. H. Abidi, O. S. AbouZeid, N. L. Abraham, H. Abramowicz, H. Abreu, Y. Abulaiti, B. S. Acharya, B. Achkar, L. Adam, C. Adam Bourdarios, L. Adamczyk, L. Adamek, J. Adelman, M. Adersberger, A. Adiguzel, S. Adorni, T. Adye, A. A. Affolder, Y. Afik, C. Agapopoulou, M. N. Agaras, A. Aggarwal, C. Agheorghiesei, J. A. Aguilar-Saavedra
A search is presented for new phenomena in events characterised by high jet multiplicity, no leptons (electrons or muons), and four or more jets originating from the fragmentation of b-quarks (b-jets). The search uses \(139~\hbox {fb}^{-1}\) of \(\sqrt{s}\) = 13 TeV proton–proton collision data collected by the ATLAS experiment at the Large Hadron Collider during Run 2. The dominant Standard Model
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A study of $$\varLambda $$ Λ and $$\bar{\varLambda }$$ Λ ¯ polarization splitting by meson field in PICR hydrodynamic model Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-11 Yilong Xie, Gang Chen, Laszlo Pal Csernai
With the PICR hydrodynamic model, we study the polarization splitting between \(\varLambda \) and \(\bar{\varLambda }\) at RHIC BES energy range, based on the meson field mechanism. Our results fit to the experimental data fairly well. Besides, two unexpected effect emerges: (1) the baryon density gradient has non-trivial and negative contribution to the polarization splitting; (2) for 7.7 GeV Au+Au
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Search for dark matter produced in association with a leptonically decaying $${\mathrm{Z}} $$ Z boson in proton–proton collisions at $$\sqrt{s}=13\,\text {Te}\text {V} $$ s = 13 Te Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-11 A. M. Sirunyan, A. Tumasyan, W. Adam, T. Bergauer, M. Dragicevic, J. Erö, A. Escalante Del Valle, R. Frühwirth, M. Jeitler, N. Krammer, L. Lechner, D. Liko, T. Madlener, I. Mikulec, F. M. Pitters, N. Rad, J. Schieck, R. Schöfbeck, M. Spanring, S. Templ, W. Waltenberger, C.-E. Wulz, M. Zarucki, V. Chekhovsky, A. Litomin, V. Makarenko, J. Suarez Gonzalez, M. R. Darwish, E. A. De Wolf, D. Di Croce, X
A search for dark matter particles is performed using events with a Z boson candidate and large missing transverse momentum. The analysis is based on proton–proton collision data at a center-of-mass energy of 13\(\,\text {Te}\text {V}\), collected by the CMS experiment at the LHC in 2016–2018, corresponding to an integrated luminosity of 137\(\,\text {fb}^{-1}\). The search uses the decay channels
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Inflation with non-minimal kinetic and Gauss–Bonnet couplings Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-09 L. N. Granda, D. F. Jimenez
The Mukhanov–Sasaki equation is deduced from linear perturbations for a general scalar-tensor model with non-minimal coupling to curvature, to the Gauss–Bonnet invariant and non-minimal kinetic coupling to curvature. The general formulas for the power spectra of the primordial scalar and tensor fluctuations are obtained for arbitrary coupling functions. The results have been applied to models with
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Four-dimensional Brane–Chern–Simons Gravity and Cosmology Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-08 F. Gómez, S. Lepe, P. Salgado
From the field equations corresponding to a four-dimensional brane embedded in the five-dimensional spacetime of the Einstein–Chern–Simons theory for gravity, we find cosmological solutions that describe an accelerated expansion for a flat universe. Apart from a quintessence-type evolution scheme, we obtain a transient phantom evolution, which is not ruled out by the current observational data. Additionally
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Note on Tsallis holographic dark energy in Brans–Dicke cosmology Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-08 Anil Kumar Yadav
In this paper, we have investigated that the power law variation of Brans–Dicke scalar field \((\phi )\) with scale factor (a) is not validated by field equations in general for the Universe filled with dark matter and Tsallis type holographic dark energy. However, for specific choice of free parameters \((\omega = -\frac{3}{2}\) and \(n = -1)\) which are differ from its values fixed in Ghaffari et
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A model of compact and ultracompact objects in $$f(\mathcal {R})$$ f ( R ) -Palatini theory Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-08 Fernanda Alvarim Silveira, Rodrigo Maier, Santiago Esteban Perez Bergliaffa
We present the features of a model which generalizes Schwarzschild’s homogeneous star by adding a transition zone for the density near the surface. By numerically integrating the modified TOV equations for the \(f(\mathcal {R})=\mathcal {R}+\lambda \mathcal {R}^2\) Palatini theory, it is shown that the ensuing configurations are everywhere finite. Depending on the values of the relevant parameters
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Contact interaction analysis of pion GTMDs Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-06 Jin-Li Zhang, Zhu-Fang Cui, Jia-Lun Ping, Craig D. Roberts
A contact interaction is used to calculate an array of pion twist-two, -three and -four generalised transverse light-front momentum dependent parton distribution functions (GTMDs). Despite the interaction’s simplicity, many of the results are physically relevant, amongst them a statement that GTMD size and shape are largely prescribed by the scale of emergent hadronic mass. Moreover, proceeding from
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Elliptic flow of hadrons in equal-velocity quark combination mechanism in relativistic heavy-ion collisions Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-06 Jun Song, Hai-hong Li, Feng-lan Shao
We apply a quark combination model with equal-velocity combination (EVC) approximation to study the elliptic flow (\(v_{2}\)) of hadrons in heavy-ion collisions in a wide collision energy range (\(\sqrt{s_{NN}}=\) 27–5020 GeV). Utilizing the simple relationship between \(v_{2}\) of hadrons and those of quarks under EVC, we find that \(v_{2}\) of up/down quarks obtained by experimental data of proton
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Cosmology and the massive photon frequency shift in the Standard-Model Extension Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-05 Alessandro D. A. M. Spallicci, José A. Helayël-Neto, Martín López-Corredoira, Salvatore Capozziello
The total red shift z might be recast as a combination of the expansion red shift and a static shift due to the energy–momentum tensor non-conservation of a photon propagating through Electro-Magnetic (EM) fields. If massive, the photon may be described by the de Broglie–Proca (dBP) theory which satisfies the Lorentz(-Poincaré) Symmetry (LoSy) but not gauge-invariance. The latter is regained in the
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Search for top squark pair production using dilepton final states in $${\text {p}}{\text {p}}$$ pp collision data collected at $$\sqrt{s}=13\,\text {TeV} $$ s = 13 TeV Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-05 A. M. Sirunyan, A. Tumasyan, W. Adam, F. Ambrogi, T. Bergauer, M. Dragicevic, J. Erö, A. Escalante Del Valle, R. Frühwirth, M. Jeitler, N. Krammer, L. Lechner, D. Liko, T. Madlener, I. Mikulec, F. M. Pitters, N. Rad, J. Schieck, R. Schöfbeck, M. Spanring, S. Templ, W. Waltenberger, C.-E. Wulz, M. Zarucki, V. Chekhovsky, A. Litomin, V. Makarenko, J. Suarez Gonzalez, M. R. Darwish, E. A. De Wolf, D.
A search is presented for supersymmetric partners of the top quark (top squarks) in final states with two oppositely charged leptons (electrons or muons), jets identified as originating from \({\text {b}}\)quarks, and missing transverse momentum. The search uses data from proton-proton collisions at \(\sqrt{s}=13\,\text {TeV} \) collected with the CMS detector, corresponding to an integrated luminosity
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An analysis of systematic effects in finite size scaling studies using the gradient flow Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-02 Alessandro Nada, Alberto Ramos
We propose a new strategy for the determination of the step scaling function \(\sigma (u)\) in finite size scaling studies using the gradient flow. In this approach the determination of \(\sigma (u)\) is broken in two pieces: a change of the flow time at fixed physical size, and a change of the size of the system at fixed flow time. Using both perturbative arguments and a set of simulations in the
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Statistical interpretation of sterile neutrino oscillation searches at reactors Eur. Phys. J. C (IF 4.389) Pub Date : 2021-01-02 Pilar Coloma, Patrick Huber, Thomas Schwetz
A considerable experimental effort is currently under way to test the persistent hints for oscillations due to an eV-scale sterile neutrino in the data of various reactor neutrino experiments. The assessment of the statistical significance of these hints is usually based on Wilks’ theorem, whereby the assumption is made that the log-likelihood is \(\chi ^2\)-distributed. However, it is well known that
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2S and 3S State Masses and decay constants of heavy-flavour mesons in a non-relativistic QCD potential model with three-loop effects in V-scheme Eur. Phys. J. C (IF 4.389) Pub Date : 2020-12-30 Rashidul Hoque, B. J. Hazarika, D. K. Choudhury
We make an analysis of three -loop effects of the strong coupling constant in the study of masses and decay constants of the heavy-flavour pseudo-scalar mesons (PSM) D, \(D_s\) , B, \(B_s,\) \(B_c\), \(\eta _c\) and \(\eta _b\) in a non-relativistic QCD potential model using Dalgarno’s perturbation theory (DPT). The first order mesonic wavefunction is obtained using Dalgarno’s perturbation theory.
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Matter accretion onto a conformal gravity black hole Eur. Phys. J. C (IF 4.389) Pub Date : 2020-12-29 G. Abbas, A. Ditta
The accretion of test fluids flowing onto a black hole is investigated. Particularly, by adopting a dynamical Hamiltonian approach, we are capable to find the critical points for various cases of black hole in conformal gravity. In these cases, we have analyzed the general solutions of accretion employing the isothermal equations of state. The steady state and spherically symmetric accretion of different
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The naturalness in the BLMSSM and B-LSSM Eur. Phys. J. C (IF 4.389) Pub Date : 2020-12-29 Xing-Xing Dong, Tai-Fu Feng, Shu-Min Zhao, Hai-Bin Zhang
In order to interpret the Higgs boson mass and its decays naturally, we hope to examine the BLMSSM and B-LSSM. In the both models, the right-handed neutrino superfields are introduced to better explain the neutrino mass problems. In this paper, we introduce the fine-tuning to acquire the physical Higgs boson mass. Besides, the method of \(\chi ^2\) analyses will be adopted in the BLMSSM and B-LSSM
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Quantum corrections to the accretion onto a Schwarzschild black hole in the background of quintessence Eur. Phys. J. C (IF 4.389) Pub Date : 2020-12-29 Kourosh Nozari, Milad Hajebrahimi, Sara Saghafi
It is well known that quantum effects may lead to removal of the intrinsic singularity point of back holes. Also, the quintessence scalar field is a candidate model for describing late-time acceleration expansion. Accordingly, Kazakov and Solodukhin considered the existence of back-reaction of the spacetime due to the quantum fluctuations of the background metric to deform a Schwarzschild black hole
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Vacua and exact solutions in lower- D limits of EGB Eur. Phys. J. C (IF 4.389) Pub Date : 2020-12-29 Liang Ma, H. Lü
We consider the action principles that are the lower dimensional limits of the Einstein–Gauss–Bonnet gravity via the Kaluza–Klein route. We study the vacua and obtain some exact solutions. We find that the reality condition of the theories may select one vacuum over the other from the two vacua that typically arise in Einstein–Gauss–Bonnet gravity. We obtain exact black hole and cosmological solutions
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The growth factor parametrization versus numerical solutions in flat and non-flat dark energy models Eur. Phys. J. C (IF 4.389) Pub Date : 2020-12-29 A. M. Velasquez-Toribio, Júlio C. Fabris
In the present investigation we use observational data of \( f \sigma _ {8} \) to determine observational constraints in the plane \((\Omega _{m0},\sigma _{8})\) using two different methods: the growth factor parametrization and the numerical solutions method for density contrast, \(\delta _{m}\). We verified the correspondence between both methods for three models of accelerated expansion: the \(\Lambda
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HiggsBounds-5 : testing Higgs sectors in the LHC 13 TeV Era Eur. Phys. J. C (IF 4.389) Pub Date : 2020-12-29 Philip Bechtle, Daniel Dercks, Sven Heinemeyer, Tobias Klingl, Tim Stefaniak, Georg Weiglein, Jonas Wittbrodt
We describe recent developments of the public computer code HiggsBounds. In particular, these include the incorporation of LHC Higgs search results from Run 2 at a center-of-mass energy of 13 TeV, and an updated and extended framework for the theoretical input that accounts for improved Higgs cross section and branching ratio predictions and new search channels. We furthermore discuss an improved method
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Neutrino amplitude decomposition: toward observing the atmospheric-solar wave interference Eur. Phys. J. C (IF 4.389) Pub Date : 2020-12-29 Hisakazu Minakata
Observation of the interference between the atmospheric and solar oscillation waves with the correct magnitude would provide another manifestation of the three-generation structure of leptons. As a prerequisite for such analyses we develop a method for decomposing the oscillation S matrix into the atmospheric and solar amplitudes. Though the similar method was recently proposed successfully in vacuum
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Spin-induced scalarization of Kerr black holes with a massive scalar field Eur. Phys. J. C (IF 4.389) Pub Date : 2020-12-29 Daniela D. Doneva, Lucas G. Collodel, Christian J. Krüger, Stoytcho S. Yazadjiev
In the present paper we study the onset of the spin-induced scalarization of a Kerr black hole in scalar-Gauss–Bonnet gravity with a massive scalar field. Our approach is based on a \((2+1)\) time evolution of the relevant linearized scalar field perturbation equation. We examine the region where the Kerr black hole becomes unstable giving rise to new scalarized rotating black holes with a massive
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Gravitational Landau damping for massive scalar modes Eur. Phys. J. C (IF 4.389) Pub Date : 2020-12-28 Fabio Moretti, Flavio Bombacigno, Giovanni Montani
We establish the possibility of Landau damping for gravitational scalar waves which propagate in a non-collisional gas of particles. In particular, under the hypothesis of homogeneity and isotropy, we describe the medium at the equilibrium with a Jüttner–Maxwell distribution, and we analytically determine the damping rate from the Vlasov equation. We find that damping occurs only if the phase velocity
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Interacting ghost dark energy in complex quintessence theory Eur. Phys. J. C (IF 4.389) Pub Date : 2020-12-28 Yang Liu
We employ a ghost model of interacting dark energy to obtain the equation of state \(\omega \) for ghost energy density in an FRW universe in complex quintessence theory. We reconstruct the potential and study the dynamics of the scalar field that describes complex quintessence cosmology. We perform \(\omega -\omega '\) analysis and stability analysis for both non-interacting and interacting cases
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Analytic baby skyrmions at finite density Eur. Phys. J. C (IF 4.389) Pub Date : 2020-12-28 Marco Barsanti, Stefano Bolognesi, Fabrizio Canfora, Gianni Tallarita
We study the baby Skyrme model in (2+1)-dimensions built on a finite cylinder. To this end, we introduce a consistent ansatz which is able to reduce the complete set of field equations to just one equation for the profile function for arbitrary baryon charge. Many analytic solutions both with and without the inclusion of the effects of the minimal coupling with the Maxwell field are constructed. The
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Sterile neutrinos with altered dispersion relations as an explanation for neutrino anomalies Eur. Phys. J. C (IF 4.389) Pub Date : 2020-12-28 Dominik Döring, Heinrich Päs, Philipp Sicking, Thomas J. Weiler
Recently the MiniBooNE Collaboration has confirmed its anomalous excess in \(\overset{\scriptscriptstyle (-)}{\nu }_\mu \rightarrow \overset{\scriptscriptstyle (-)}{\nu }_e\) neutrino oscillation data. Combined with long-standing results from the LSND experiment this amounts to a \(6.1\,\sigma \) evidence for new physics beyond the Standard Model. In this paper we develop a framework with 3 active
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Schwarzschild-like solutions in Finsler–Randers gravity Eur. Phys. J. C (IF 4.389) Pub Date : 2020-12-28 A. Triantafyllopoulos, S. Basilakos, E. Kapsabelis, P. C. Stavrinos
In this work, we extend for the first time the spherically symmetric Schwarzschild and Schwarzschild–De Sitter solutions with a Finsler–Randers-type perturbation which is generated by a covector \(A_\gamma \). This gives a locally anisotropic character to the metric and induces a deviation from the Riemannian models of gravity. A natural framework for this study is the Lorentz tangent bundle of a spacetime
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Strong interaction of doubly heavy spin-3/2 baryons with light vector mesons Eur. Phys. J. C (IF 4.389) Pub Date : 2020-12-24 K. Azizi, A. R. Olamaei, S. Rostami
We calculate the strong coupling constants among the doubly heavy spin-\( \frac{3}{2} \) baryons \(\Xi ^*_{QQ}\) and \(\Omega ^*_{QQ}\), with Q and \( Q' \) being c or b quark, with light vector meson by means of the light-cone QCD sum rules. The matrix elements defining these vertices are described by four coupling constants \( g_1\), \( g_2\), \( g_3\), and \( g_4 \). The unwanted pollution coming
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Off-shell $${\mathcal {N}}=(1,0)$$ N = ( 1 , 0 ) linear multiplets in six dimensions Eur. Phys. J. C (IF 4.389) Pub Date : 2020-12-24 Ugur Atli, Omer Guleryuz, Mehmet Ozkan
We provide a tensor calculus for n-number of \({\mathcal {N}}= (1,0)\) linear multiplets in six dimensions. The coupling of linear multiplets is encoded in a function \({\mathcal {F}}_{IJ}\) that is subject to certain constraints. We provide various rigid and local supersymmetric models depending on the choice of the function \({\mathcal {F}}_{IJ}\) and provide an interesting off-diagonal superinvariant
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The generic sudden singularity in Brans–Dicke theory Eur. Phys. J. C (IF 4.389) Pub Date : 2020-12-24 John D. Barrow, Spiros Cotsakis, Dimitrios Trachilis
We construct a formal asymptotic series expansion for a general solution of the Brans–Dicke equations with a fluid source near a sudden singularity. This solution contains 11 independent arbitrary functions of the spatial coordinates as required by the Cauchy problem of the theory. We show that the solution is geodesically complete and has the character of a shock wave in the sudden asymptotic region
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Bianchi type- III Tsallis holographic dark energy model in Saez–Ballester theory of gravitation Eur. Phys. J. C (IF 4.389) Pub Date : 2020-12-24 M. Vijaya Santhi, Y. Sobhanbabu
In this paper, we have investigated Tsallis holographic dark energy (infrared cutoff is the Hubble radius) in homogeneous and anisotropic Bianchi type-III Universe within the framework of Saez–Ballester scalar–tensor theory of gravitation. We have constructed non-interaction and interaction dark energy models by solving the Saez–Ballester field equations. To solve the field equations, we assume a relationship
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An effective field theory approach for electroweak interactions in the high energy limit Eur. Phys. J. C (IF 4.389) Pub Date : 2020-12-24 Melina Gómez Bock, Martin Hentschinski, Agustín Sabio Vera
We present an effective action for the electroweak sector of the standard model valid for the calculation of scattering amplitudes in the high energy (Regge) limit. Gauge invariant Wilson lines are introduced to describe reggeized degrees of freedom whose interactions are generated by effective emission vertices. From this approach previous results at leading logarithmic accuracy for electroweak boson
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Shadows of rotating Hayward–de Sitter black holes with astrometric observables Eur. Phys. J. C (IF 4.389) Pub Date : 2020-12-24 Peng-Zhang He, Qi-Qi Fan, Hao-Ran Zhang, Jian-Bo Deng
Motivated by recent work on rotating black hole shadow (Chang and Zhu in Phys Rev D 101:084029, 2020), we investigate the shadow behaviours of rotating Hayward–de Sitter black hole for static observers at a finite distance in terms of astronomical observables. This paper uses the newly introduced distortion parameter (Chang and Zhu in Phys Rev D 102:044012, 2020) to describe the shadow’s shape quantitatively
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Alignment of the ATLAS Inner Detector in Run 2 Eur. Phys. J. C (IF 4.389) Pub Date : 2020-12-24 G. Aad, B. Abbott, D. C. Abbott, A. Abed Abud, K. Abeling, D. K. Abhayasinghe, S. H. Abidi, O. S. AbouZeid, N. L. Abraham, H. Abramowicz, H. Abreu, Y. Abulaiti, B. S. Acharya, B. Achkar, L. Adam, C. Adam Bourdarios, L. Adamczyk, L. Adamek, J. Adelman, M. Adersberger, A. Adiguzel, S. Adorni, T. Adye, A. A. Affolder, Y. Afik, C. Agapopoulou, M. N. Agaras, A. Aggarwal, C. Agheorghiesei, J. A. Aguilar-Saavedra
The performance of the ATLAS Inner Detector alignment has been studied using pp collision data at \(\sqrt{s} = 13\,\hbox {TeV}\) collected by the ATLAS experiment during Run 2 (2015–2018) of the Large Hadron Collider (LHC). The goal of the detector alignment is to determine the detector geometry as accurately as possible and correct for time-dependent movements. The Inner Detector alignment is based
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Relativistic Friedrichs–Lee model and quark-pair creation model Eur. Phys. J. C (IF 4.389) Pub Date : 2020-12-24 Zhi-Yong Zhou, Zhiguang Xiao
In this paper, we present how the Friedrichs–Lee model could be extended to the relativistic scenario and be combined with the relativistic quark pair creation model in a consistent way. This scheme could be applied to study the “unquenched” effect of the meson spectra. As an example, if the lowest \(J^{PC}=0^{++}\) \((u\bar{u}+d\bar{d})/\sqrt{2}\) bound state in the potential model is coupled to the
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A theoretical analysis of the semileptonic decays $$\eta ^{(\prime )}\rightarrow \pi ^0l^+l^-$$ η ( ′ ) → π 0 l + l - and $$\eta ^\prime \rightarrow \eta l^+l^-$$ η ′ → η l + l - Eur. Phys. J. C (IF 4.389) Pub Date : 2020-12-24 Rafel Escribano, Emilio Royo
A complete theoretical analysis of the C- conserving semileptonic decays \(\eta ^{(\prime )}\rightarrow \pi ^0l^+l^-\) and \(\eta ^\prime \rightarrow \eta l^+l^-\) (\(l=e\) or \(\mu \)) is carried out within the framework of the Vector Meson Dominance (VMD) model. An existing phenomenological model is used to parametrise the VMD coupling constants and the associated numerical values are obtained from
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Einstein–æther models III: conformally static metrics, perfect fluid and scalar fields Eur. Phys. J. C (IF 4.389) Pub Date : 2020-12-24 Genly Leon, Alfredo D. Millano, Joey Latta
The asymptotic properties of conformally static metrics in Einstein–æther theory with a perfect fluid source and a scalar field are analyzed. In case of perfect fluid, some relativistic solutions are recovered such as: Minkowski spacetime, the Kasner solution, a flat FLRW space and static orbits depending on the barotropic parameter \(\gamma \). To analyze locally the behavior of the solutions near
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Measurement of exclusive $${\varvec{{{{\pi ^+\pi ^-}}}}}$$ π + π - and $${\varvec{{{{\rho ^0}}}}}$$ ρ 0 meson photoproduction at HERA Eur. Phys. J. C (IF 4.389) Pub Date : 2020-12-23 V. Andreev, A. Baghdasaryan, A. Baty, K. Begzsuren, A. Belousov, A. Bolz, V. Boudry, G. Brandt, D. Britzger, A. Buniatyan, L. Bystritskaya, A. J. Campbell, K. B. Cantun Avila, K. Cerny, V. Chekelian, Z. Chen, J. G. Contreras, J. Cvach, J. B. Dainton, K. Daum, A. Deshpande, C. Diaconu, G. Eckerlin, S. Egli, E. Elsen, L. Favart, A. Fedotov, J. Feltesse, M. Fleischer, A. Fomenko, C. Gal, J. Gayler, L
Exclusive photoproduction of \({{\rho ^0}} (770)\) mesons is studied using the H1 detector at the ep collider HERA. A sample of about 900,000 events is used to measure single- and double-differential cross sections for the reaction \(\gamma p \rightarrow \pi ^{+}\pi ^{-}Y\). Reactions where the proton stays intact (\({{{m_Y}} {=}m_p}\)) are statistically separated from those where the proton dissociates
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Electroweak stability and discovery luminosities for new physics Eur. Phys. J. C (IF 4.389) Pub Date : 2020-12-23 Kerem Cankoçak, Durmuş Demir, Canan Karahan, Sercan Şen
What is the luminosity needed for discovering new physics if the electroweak scale is to remain stable? In this work we study this question, with the pertinent example of a real singlet scalar which couples to the Higgs field at the renormalizable level. Observing that the electroweak scale remains stable if the two scalars couple in a see-sawic fashion through a mass-degeneracy-driven unification
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Description of the newly observed $$\Xi _c^{0}$$ Ξ c 0 states as molecular states Eur. Phys. J. C (IF 4.389) Pub Date : 2020-12-23 HongQiang Zhu, NaNa Ma, Yin Huang
Very recently, three new structures \(\Xi _c(2923)^0\), \(\Xi _c(2938)^0\), and \(\Xi _c(2964)^0\) at the invariant mass spectrum of \(\Lambda _c^{+}K^{-}\) observed by the LHCb Collaboration trigger a hot discussion about their inner structure. In this work, we study the strong decay mode of the newly observed \(\Xi ^0_c\) assuming that the \(\Xi ^0_c\) is a \(\bar{D}\Lambda -\bar{D}\Sigma \) molecular
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Prospects of measuring the branching fraction of the Higgs boson decaying into muon pairs at the International Linear Collider Eur. Phys. J. C (IF 4.389) Pub Date : 2020-12-23 Shin-ichi Kawada, Jenny List, Mikael Berggren
The prospects for measuring the branching fraction of \(H \rightarrow \mu ^{+} \mu ^{-}\) at the International Linear Collider (ILC) have been evaluated based on a full detector simulation of the International Large Detector (ILD) concept, considering centre-of-mass energies (\(\sqrt{s}\)) of 250 GeV and 500 GeV with two different beam polarisation configurations of \({\mathcal {P}} (e^{-}, e^{+})
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On the modelling of energetic multi-jet QCD events Eur. Phys. J. C (IF 4.389) Pub Date : 2020-12-23 Daniel Turgeman, Michael Pitt, Itamar Roth, Ehud Duchovni
Physics beyond the Standard Model (BSM) may be unveiled by studying events with a high number of outgoing jets, produced at the LHC with energies above the TeV scale (energetic multi-jet events). Such events are dominated by QCD processes, where the calculations rely on some sort of approximation. Therefore, it is important to develop a robust approach for modeling such events that could probe the
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