HEP Phenomenology·hep-ph

Fri·Jan 4, 2019Friday·January 4, 2019

11 papers—6 primary·5 cross-listed·reconstructed*

01*
Studying $X (2100)$ hadronic decays and predicting its pion and kaon induced productions
Li-Ming Wang🇨🇳 · Jun-Zhang Wang🇨🇳 · Si-Qiang Luo🇨🇳 · Jun He🇨🇳 · Xiang Liu🇨🇳
The newly observed $X (2100)$ by the BESIII Collaboration inspires our interest in studying the light meson system, especially axial-vector mesons. Since the $X (2100)$ has $J^{P} = 1^{+}$ possibilities but cannot be distinguished only by mass, we make use of flux-tube model to study the strong decay behavior of $X (2100)$ under this assignment. The experimental width of the newly reported $X (2100)$ can be reproduced in our calculation, which favors an assignment of $X (2100)$ as the second radial excitation of $h_{1} (1380)$ with $I (J^{P}) = 0 (1^{+})$ . And the $B (X (2100) \to ϕ η^{'})$ has a sizable contribution to the total width. Furthermore, we focus on the production of $X (2100)$ and its flavour partner $h_{1} (1965)$ induced by pion and kaon on a proton target with the Feynman model and the Regge model, which is an available platform to further identify their nature. The numerical results indicate that the total cross section are similar in the two models. When the range of momentum $p_{Lab}$ is 10 to 30 GeV/ $c$ , the total cross sections for $π^{-} p \to X (2100) n$ and $K^{-} p \to X (2100) Λ$ are predicted to be at an order of magnitude of 0.1 $μ$ b. Whereas, the total cross section for $π^{-} p \to h_{1} (1965) n$ is near an order of magnitude of 10 $μ$ b when $p_{Lab}$ is from 10 to 30 GeV/ $c$ , and much larger than that of reaction $K^{-} p \to h_{1} (1965) Λ$ . These predictions can provide some valuable information to search for $X (2100)$ and $h_{1} (1965)$ in experiments at J-PARC, COMPASS, OKA@U-70 and SPS@CERN.
hep-phhep-exPRD(2020)·22 citations
02*
Neutral-current weak pion production off the nucleon in covariant chiral perturbation theory
De-Liang Yao🇪🇸 · Luis Alvarez-Ruso🇪🇸 · M. J. Vicente Vacas🇪🇸
Neutral current single pion production induced by neutrinos and antineutrinos on nucleon targets has been investigated in manifestly relativistic baryon chiral perturbation theory with explicit $Δ (1232)$ degrees of freedom up to $O (p^{3})$ . At low energies, where chiral perturbation theory is applicable, the total cross sections for the different reaction channels exhibit a sizable non-resonant contribution, which is not present in event generators of broad use in neutrino oscillation and cross section experiments such as GENIE and NuWro.
hep-phPLB(2019)·24 citations
03*
Mass Spectrum of Exotic X(5568) State via Artificial Neural Network
Halil Mutuk🇹🇷
In this paper, we assume $X (5568)$ exist and study mass spectrum of $X (5568)$ resonance and its hypothetical charmed partner, $X_{c}$ , by Artificial Neural Network method. The obtained predictions are compared with the experimental data and results of other theoretical works.
hep-phInt.J.Mod.Phys.A(2019)·6 citations
04*
Dynamical Symmetry Breaking and Negative Cosmological Constant
Wei Lu🇺🇸
In the context of Clifford functional integral formalism, we revisit the Nambu-Jona-Lasinio-type dynamical symmetry breaking model and examine the properties of the dynamically generated composite bosons. Given that the model with 4-fermion interactions is nonrenormalizable in the traditional sense, the aim is to gain insight into the divergent integrals without resorting to explicit regularization. We impose a restriction on the linearly divergent primitive integrals, thus resolving the long-standing issue of momentum routing ambiguity associated with fermion-antifermion condensations. The removal of the ambiguity paves the way for the possible calculation of the true ratio of Higgs boson mass to top quark mass in the top condensation model. In this paper, we also investigate the negative vacuum energy resulted from dynamical symmetry breaking and its cosmological implications. In the framework of modified Einstein-Cartan gravity, it is demonstrated that the late-time acceleration is driven by a novel way of embedding the Hubble parameter into the Friedmann equation via an interpolation function, whereas the dynamically generated negative cosmological constant only plays a minor role for the current epoch. Two cosmic scenarios are proposed, with one of which suggesting that the universe may have been evolving from an everlasting coasting state towards the accelerating era characterized by the deceleration parameter approaching -0.5 at low redshift. One inevitable outcome of the modified Friedmannian cosmology is that the directly measured local Hubble parameter should in general be larger than the Hubble parameter calibrated from the conventional Friedmann equation. This Hubble tension becomes more pronounced when the Hubble parameter is comparable or less than a characteristic Hubble scale.
hep-phastro-ph.COgr-qchep-thInt.J.Mod.Phys.A(2019)·3 citations
05*
Exotic Leptonic solutions to observed anomalies in lepton universality observables and more
Lobsang Dhargyal🇮🇳
In this talk I will present the work that we did in \cite{1}\cite{2}\cite{3}\cite{4}\cite{5} related to observed lepton universality violation by Babar, Belle and LHCb in R( $D^{(*)}$ ) and $R_{K^{(*)}}$ as well as the reported deviation in muon (g-2) by BNL. We had shown that all these anomalies as well as Baryon-genesis, Dark-matter and small neutrino masses could be explained by introducing new exotic scalars, leptons and scalar-leptoquarks only. It turn out that some of these models have very peculiar signatures such as prediction of existence of heavy stable charged particle \cite{1}\cite{2}, vector like fourth generation leptons \cite{3} or even scalar Baryonic DM candidates etc. Some of these models turn out to have very unique collider signatures such as $ee / pp \to μμ (τ τ) + mi ss in g e n er g y (M E)$ , see \cite{1}\cite{2}\cite{4}. This is interesting in the sense that such peculiar signatures of these new particles can be searched in the upcoming HL-LHC or with even better chance of observing these signatures are in the upcoming precision machines such as ILC, CEPC etc.
hep-phSpringer Proc.Phys.(2021)·0 citations
06*
B-tagging and searches for new physics beyond the Standard Model
T.V. Obikhod🇺🇦 · I.A. Petrenko🇺🇦
The article is devoted to the searches for new particles predicted by physics beyond the Standard Model through the b-tagging algorithm. The dependence of b-tagging efficiency on the jet identification, impact parameter identification, secondary vertex identification, kinematic cuts is studied with the help of computer programs Pythia 8.2 and Fastjet 3.3.0. The selection criteria for kinematic parameters, their ratios for an optimal result on the reconstruction of the vertices of heavy particles are found.
hep-phProb.Atomic Sci.Technol.(2020)·1 citation
07*
Bounded particle interactions driven by a nonlocal dual Chern-Simons model
Van Sérgio Alves🇧🇷 · E. C. Marino🇧🇷 · Leandro O. Nascimento🇧🇷 · J. F. Medeiros Neto🇧🇷 · Rodrigo F. Ozela🇧🇷 · Rudnei O. Ramos🇧🇷
Quantum electrodynamics (QED) of electrons confined in a plane and that yet can undergo interactions mediated by an unconstrained photon has been described by the so-called {\it pseudo-QED} (PQED), the (2+1)-dimensional version of the equivalent dimensionally reduced original QED. In this work, we show that PQED with a nonlocal Chern-Simons term is dual to the Chern-Simons Higgs model at the quantum level. We apply the path-integral formalism in the dualization of the Chern-Simons Higgs model to first describe the interaction between quantum vortex particle excitations in the dual model. This interaction is explicitly shown to be in the form of a Bessel-like type of potential in the static limit. This result {\it per se} opens exciting possibilities for investigating topological states of matter generated by interactions, since the main difference between our new model and the PQED is the presence of a nonlocal Chern-Simons action. Indeed, the dual transformation yields an unexpected square root of the d'Alembertian operator, namely, $(- □)^{- 1}$ multiplied by the well-known Chern-Simons action. Despite the nonlocality, the resulting model is still gauge invariant and preserves the unitarity, as we explicitly prove. {}Finally, when coupling the resulting model to Dirac fermions, we then show that pairs of bounded electrons are expected to appear, with a typical distance between the particles being inversely proportional to the topologically generated mass for the gauge field in the dual model.
↳ hep-thcond-mat.str-elhep-phPLB(2019)·12 citations
08*
Gravitational Instabilities and Censorship of Large Scalar Field Excursions
Patrick Draper🇺🇸 · Szilard Farkas🇺🇸
Large, localized variations of light scalar fields tend to collapse into black holes, dynamically "censoring" distant points in field space. We show that in some cases, large scalar excursions in asymptotically flat spacetimes can be UV-completed by smooth Kaluza-Klein bubble geometries, appearing to circumvent 4d censorship arguments. However, these spacetimes also exhibit classical instabilities related to the collapse or expansion of a bubble of nothing, providing a different censorship mechanism. We show that the Kerr family of static KK bubbles, which gives rise to an infinite scalar excursion upon dimensional reduction, is classically unstable. We construct a family of initial data in which the static bubbles sit at a local maximum of the energy, and we give a general argument that such a property indeed indicates mechanical instability in gravity. We also discuss the behavior of wound strings near a bubble, a local probe of the large traversal through moduli space.
↳ hep-thgr-qchep-phJHEP(2019)·20 citations
09*
Acceleration due to buoyancy and mass renormalization
Kyle McKee🇨🇦 · Andrzej Czarnecki🇨🇦
The acceleration of a light buoyant object in a fluid is analyzed. Misconceptions about the magnitude of that acceleration are briefly described and refuted. The notion of the added mass is explained and the added mass is computed for an ellipsoid of revolution. A simple approximation scheme is employed to derive the added mass of a slender body. The slender-body limit is non-analytic, indicating a singular character of the perturbation due to the thickness of the body. An experimental determination of the acceleration is presented and found to agree well with the theoretical prediction. The added mass illustrates the concept of mass renormalization in an accessible manner.
↳ physics.flu-dynhep-phhep-thAm.J.Phys.(2019)·1 citation
10*
Quark orbital angular momentum in the proton evaluated using a direct derivative method
M. Engelhardt🇺🇸 · J. Green🇩🇪 · N. Hasan🇩🇪 · S. Krieg🇩🇪 · S. Meinel🇺🇸 · J. Negele🇺🇸 · A. Pochinsky🇺🇸 · S. Syritsyn🇺🇸
Quark orbital angular momentum (OAM) in the proton can be calculated directly given a Wigner function encoding the simultaneous distribution of quark transverse positions and momenta. This distribution can be accessed via proton matrix elements of a quark bilocal operator (the separation in which is Fourier conjugate to the quark momentum) featuring a momentum transfer (which is Fourier conjugate to the quark position). To generate the weighting by quark transverse position needed to calculate OAM, a derivative with respect to momentum transfer is consequently required. This derivative is evaluated using a direct derivative method, i.e., a method in which the momentum derivative of a correlator is directly sampled in the lattice calculation, as opposed to extracting it a posteriori from the numerical correlator data. The method removes the bias stemming from estimating the derivative a posteriori that was seen to afflict a previous exploratory calculation. Data for Ji OAM generated on a clover ensemble at pion mass $m_{π} = 317 \mbox M e V$ are seen to agree with the result obtained via the traditional Ji sum rule method. By varying the gauge connection in the quark bilocal operator, also Jaffe-Manohar OAM is extracted, and seen to be enhanced significantly compared to Ji OAM.
↳ hep-lathep-phPoS(2018)·6 citations
11*
Effect of Scalar Boson on Fermionic Dark Star
A. B. Wahidin🇮🇩 · A. Rahmansyah🇮🇩 · A. Sulaksono🇮🇩
The role of scalar boson exchange as a mediator of the fermionic dark particle interaction and the mass of dark particle on the bulk properties of fermionic dark stars including their moment of inertia and tidal deformability are studied. We have found that the role of the attractive nature of the scalar boson exchange and the fermionic dark particle mass can control the stiffness of the fermionic dark star equation of state. By increasing the strength of scalar boson coupling, the fermionic dark star becomes more compact. As a consequence, if scalar boson exchange contribution is included the compactness of a dark star can exceed $C$ =0.22. We also compare the fermionic dark stars moment of inertia and tidal deformability to those of neutron stars (with and without hyperons in neutron star core) predicted by relativistic mean field model. It is evidence that the properties of both types of stars are quite different. We also have found that the universal I-Love relation in fermionic dark stars is not affected by scalar boson exchange contribution and the fermionic dark particle mass. Possible observations of fermionic dark stars are also discussed.
↳ gr-qcastro-ph.SRhep-phnucl-thInt.J.Mod.Phys.D(2019)·5 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.