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I review possible signals at hadron colliders of bileptons, namely doubly charged vectors or scalars with lepton number L = ± 2 , as predicted by a 331 model, based on a S U (3) c × S U (3) L × U (1) X symmetry. In particular, I account for a version of the 331 model wherein the embedding of the hypercharge is obtained with the addition of three exotic quarks and vector bileptons. Furthermore, a sextet of S U (3) L , necessary to provide masses to leptons, yields an extra scalar sector, including a doubly charged Higgs, i.e., scalar bileptons. As bileptons are mostly produced in pairs at hadron colliders, their main signal is provided by two same-sign lepton pairs at high invariant mass. Nevertheless, they can also decay according to non-leptonic modes, such as a TeV-scale heavy quark, charged 4/3 or 5/3, plus a Standard Model quark. I explore both leptonic and non-leptonic decays and the sensitivity to the processes of the present and future hadron colliders. [ABSTRACT FROM AUTHOR]

The effective baryon–baryon potential can be derived in the framework of the quark model. The configurations with different quark spatial distributions are mixed naturally when two baryons get close. The effect of configuration mixing in the chiral quark model (ChQM) is studied by calculating the effective potential between two non-strange baryons in the channels I J = 01 , 10 and 03. For comparison, the results of the color screening model (CSM) are also presented. Generally, configuration mixing will lower the potential when the separation between two baryons is small, and its effect will be ignorable when the separation becomes large. Due to the screened color confinement, the effect of configuration mixing is rather large, which leads to stronger intermediate-range attraction in the CSM, while the effect of configuration mixing is small in the ChQM due to the quadratic confinement and σ -meson exchange, which is responsible for the intermediate-range attraction. [ABSTRACT FROM AUTHOR]

Four SU(5)N=1$SU(5) \nobreakspace N=1$ supersymmetric models which exhibit S3$S_3$ and/or ZN$Z_N$ symmetries are studied, that are finite to two or all loops, and their corresponding mass matrices. The first is an all‐loop finite model based on an S3×Z3×Z2$S_3\times Z_3\times Z_2$ flavor symmetry, which leads to phenomenologically nonviable mass matrices. The remaining models, based on cyclic symmetries, show various mass textures, some of which are phenomenologically promising. For the two‐loop finite models, the parametric solutions to the finiteness conditions determine completely some of the Yukawa couplings, and lead to a restricted range of values for other ones at the GUT scale, with a considerable reduction in the number of free parameters. One particular solution of the two‐loop models shows an enhanced symmetry, leading to an all‐loop finite model, which has a significant parameter reduction and could in principle reproduce the observed quark masses and mixing pattern. In this case the finiteness conditions determine the absolute value of all the Yukawa couplings at the unification scale. Finally, the minimum number of phases in the mass matrices and their position are determined, a task not previously done in Finite Unified Theories, which contributes towards the reduction of parameters and a better understanding of the Yukawa couplings. [ABSTRACT FROM AUTHOR]

In this paper, we study a class of conformal metric deformations in the quasi-radial coordinate parametrizing the three-sphere in the conformally compactified Minkowski spacetime S 1 × S 3 . Prior to reduction of the associated Laplace–Beltrami operators to a Schrödinger form, a corresponding class of exactly solvable potentials (each one containing a scalar and a gradient term) is found. In particular, the scalar piece of these potentials can be exactly or quasi-exactly solvable, and among them we find the finite range confining trigonometric potentials of Pöschl–Teller, Scarf and Rosen–Morse. As an application of the results developed in the paper, the large compactification radius limit of the interaction described by some of these potentials is studied, and this regime is shown to be relevant to a quantum mechanical quark deconfinement mechanism. [ABSTRACT FROM AUTHOR]

In this report, I discuss some of the most recent lattice spectroscopy calculations of hadrons and hadronic resonances involving charm quarks, with special emphasis on those that are relevant from an experimental perspective. [ABSTRACT FROM AUTHOR]

In this paper, we have employed HQET to determine the masses of radially excited (n = 2) S-wave charm and bottom baryons. The HQET Lagrangian containing the non-perturbative parameters is shown with heavy baryon fields. The non-perturbative parameters, couplings, and decay widths are also studied for the S-wave singly heavy baryons. The HQET parameters Λ ¯ , λ 1 and λ 2 are calculated for the ground state (n = 1) using the masses of S-wave baryons. The 1 S mass short-distance mass scheme is employed to estimate the heavy quark masses and non-perturbative parameters. The mass term ratios of n = 1 and n = 2 mesons and baryons containing parameters Λ ¯ and λ 1 are studied by varying the bottom quark mass. This analysis shows that heavy quarks behave the same inside mesons and baryons in both 1S and 2S states. The HQET symmetry of Λ ¯ is used to find the parameters and masses for n = 2 S-wave baryons. The variation of mass of 2S baryons with the non-perturbative parameters λ 1 and λ 2 is discussed. The Regge trajectories are also plotted in the (n , M 2) plane using masses of n = 1 and 2 charm and bottom baryons. The Regge trajectories are parallel and equidistant lines in the (n , M 2) plane. We have also studied the strong decays of charm and bottom baryons for both n = 1 and n = 2 states. We have estimated the coupling constants g 1 = 0. 9 1 3 − 0. 0 1 7 + 0. 0 1 0 and g 2 = 0. 5 5 9 − 0. 0 1 0 + 0. 0 0 6 for n = 1 , and g ̃ 1 g ̃ 2 = 1. 5 2 for n = 2. We have also shown the semi-electronic decay rates of charm baryons in the spectator heavy quark approximation for 1 S → 1 S , 2 S → 1 S , and 2 S → 2 S transitions. The decay rates for 1 S → 1 S transitions are of the same order as 2 S → 2 S transitions. This analysis agrees well with the available theoretical and experimental data. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate the effect of starter cultures on the physicochemical and microbiological properties, texture, yield, and consumer preferences of quark type cheese. For this purpose, three different quark cheeses were manufactured by using commercial starter cultures. The microbiological, physicochemical, textural, and sensory properties of the cheese samples were determined at 1st, 14th, and 28th days of the storage period. The results showed that the kind of starter culture used in production influences the composition and yield of the obtained quark cheeses. It has been determined that the use of kefir culture in quark cheese production influences the moisture and water holding capacity, and as a result, improves its spreadability. Also, the sensory analysis exhibited that cheese produced with kefir culture had higher texture and taste-flavor acceptability. The study indicates that kefir culture may be successfully used in quark cheese production. [ABSTRACT FROM AUTHOR]

In the absence of a Grand Unified Theory framework, connecting the values of the mixing parameters in the quark-and-lepton sector is a difficult task, unless one introduces ad hoc relations among the matrices that diagonalize such different kinds of fermions. In this paper, we discuss in detail the possibility that the PMNS matrix is given by the product U P M N S = V C K M ★ T ★ , where T comes from the diagonalization of a see-saw like mass matrix that can be of a Bimaximal (BM), Tri-Bimaximal (TBM) and Golden Ratio (GR) form, and identify the leading corrections to such patterns that allow for a good fit to the leptonic mixing matrix as well as to the CP phase. We also show that the modified versions of BM, TBM and GR can easily accommodate the solar and atmospheric mass differences. [ABSTRACT FROM AUTHOR]

A discussion is presented of the estimates of the energy and width of resonances in constituent models, with focus on the tetraquark states containing heavy quarks. [ABSTRACT FROM AUTHOR]

A relation between the radii and masses of the quarks and leptons is established for each fermion generation. Kinematical calculations provide a proof of the essential stability of the proton at rest within the standard model together with conditions for the reaction p → uuu + e- + ve with a uuu composite state as a byproduct. The Koide relation reduces the scaling to a single number, and a theoretical explanation is given in terms of graded symmetries. The values of the masses of the each of the quarks are derived through nonperturbative infinite-genus effects. [ABSTRACT FROM AUTHOR]

We present the study of the quark sector of the universal seesaw model with |$\mathrm{SU(2)_L \times SU(2)_R \times U(1)_{Y^{\prime }}}$| gauge symmetry in the massless case of the two lightest quark families. This model aims to explain the mass hierarchy of the third family quark by introducing a vector-like quark (VLQ) partner for each quark. In this model, we introduce |$\mathrm{SU(2)_L}$| and |$\mathrm{SU(2)_R}$| Higgs doublets. We derive explicitly the Lagrangian for the quark sector, Higgs sector, and kinetic terms of the gauge fields, starting from the Lagrangian, which is invariant under |$\mathrm{SU(2)_L \times SU(2)_R \times U(1)_{Y^{\prime }}}$| gauge symmetry. At each stage of the symmetry breaking, we present the Lagrangian with the remaining gauge symmetry. Additionally, we investigate the flavor-changing neutral currents (FCNCs) of the Higgs (h) and Z -bosons in the interaction with the top, heavy top, bottom, and heavy bottom quarks. [ABSTRACT FROM AUTHOR]

We review and meta-analyze particle data and properties of hadrons with measured rest masses. The results of our study are summarized as follows. (1) The strong-force suppression of the repulsive Coulomb forces between quarks is sufficient to explain the differences between mass deficits in nucleons and pions (and only them), the ground states with the longest known mean lifetimes; (2) unlike mass deficits, the excitations in rest masses of all particle groups are effectively quantized, but the rules are different in baryons and mesons; (3) the strong field is aware of the extra factor of ϑ e = 2 in the charges (Q) of the positively charged quarks; (4) mass deficits incorporate contributions proportional to the mass of each valence quark; (5) the scaling factor of these contributions is the same for each quark in each group of particles, provided that the factor ϑ e = 2 is taken into account; (6) besides hypercharge (Y), the much lesser-known "strong charge" ( Q ′ = Y − Q ) is very useful in SU(3) in describing properties of particles located along the right-leaning sides and diagonals of the weight diagrams; (7) strong decays in which Q ′ is conserved are differentiated from weak decays, even for the same particle; and (8) the energy diagrams of (anti)quark transitions indicate the origin of CP violation. [ABSTRACT FROM AUTHOR]

In this work, we make a study of the τ− → ωπ−ντ decay in the framework of low-energy effective field theory. The J P G decompositions of the quark currents and the ωπ final state show that, besides the Standard Model vector interaction, only the non-standard tensor interaction can have a non-zero contribution to the decay. To discuss its effect, a reliable calculation of the ωπ tensor form factors is necessary. After constructing the Lagrangian of resonance chiral theory with external tensor sources, we calculate both the vector and tensor form factors with the relevant resonance couplings determined by combining the QCD short-distance constraints, the fit to the spectral function of τ− → ωπ−ντ decay, as well as the matching between the O p 4 odd-intrinsic-parity operators after integrating out the vector resonances and the O p 6 operators of chiral perturbation theory. The new physics effect is then investigated in the distributions of the spectral function and the forward-backward asymmetry of τ− → ωπ−ντ decay. We find that the spectral function is dominated by the Standard Model, and the non-standard tensor contribution is negligible. However, since the forward-backward asymmetry can be only generated with a non-zero tensor interaction, the observable is quite sensitive to this kind of new physics. A future measurement of the observable at the Belle II experiment as well as at the proposed Tera-Z and STCF facilities is, therefore, strongly called for to check the existence of such a non-standard tensor interaction. [ABSTRACT FROM AUTHOR]

The static properties and dynamic evolution of bottomonium states in a hot QCD medium are investigated through the Schrödinger equation with complex heavy quark potentials, which have been presented recently in a lattice QCD study and with three different extractions. This approach builds a direct connection between the in-medium heavy quark potentials from the lattice QCD to the experimental observables. The yields and nuclear modification factors R AA of bottomonium in Pb–Pb collisions at s NN = 5.02 TeV are calculated in this work. Our results show a large suppression of the bottomonium yield in heavy ion collisions due to the large imaginary potential. To understand bottomonium R AA based on lattice QCD potentials, we propose a formation time for bottomonium states and find that experimental data can be well explained with the heavy quark potential extracted by the Padé fit, which shows no color screening in the real part potential. [ABSTRACT FROM AUTHOR]

Understanding the polarization property of J / ψ is critical to constrain its production mechanism. In addition, the polarization of J / ψ can reveal the impact of strong electromagnetic and vorticity fields in relativistic heavy ion collisions. In this study, we analyzed the yield and polarization of J / ψ in relativistic heavy ion collisions at different centrality and transverse momentum regions, using three different reference frames: the Collins–Soper frame, the helicity frame, and the event plane frame. The polarization of initially produced J / ψ is determined by the NRQCD calculation and is similar to that of pp collisions. However, both unpolarization and transverse polarization are considered for the regenerated J / ψ . Our results indicate that the polarization at high p T is similar to that observed in pp collisions. However, at low p T , where regenerated J / ψ dominates, it is likely that the polarized charm quarks in the rotational QGP medium are responsible for this phenomenon. Our study supplies a baseline for future research on the effects of strong electromagnetic and vorticity fields on J / ψ polarization. [ABSTRACT FROM AUTHOR]

Taking into account the recent parameterizations of parton distribution functions (PDFs), the momentum transfer dependence of generalized parton distributions (GPDs) of nucleons is obtained in the limit . The gravitational quark and gluon form factors of nucleons are calculated. It is shown that the gluon gravitational radius of the nucleon is comparable to the electromagnetic radius of the proton. The power dependence of form factors is investigated. As a result, it was obtained that the quark gravitational form factor is reproduced by the dipole form, while the form of the gluon gravitation form factor corresponds to the triple form. [ABSTRACT FROM AUTHOR]

The work proposes a new method for measuring the gluon jet fraction in jet sample produced at the hadron collider. This method uses model quark/gluon templates—distributions of quark and gluon jets over the jet macro parameter. Within the framework of this method, it is possible to find a model uncertainty of measurement associated with the deviation of model quark/gluon templates from the true ones. The issue of data-motivated corrections to the model quark/gluon templates is discussed. [ABSTRACT FROM AUTHOR]

Interest in studying multiparticle-production processes in lepton and hadron interactions has not faded to date. The development of strong-interaction theory in the form of quantum chromodynamics (QCD) permits describing these interactions at the level of quarks and gluons. The transition from partons to observed hadrons at the hadronization stage is very difficult. The gluon-dominance model describing multiparticle production of secondaries and including the hadronization stage is proposed in the present study. This model is applied to describing electron–positron annihilation. It confirms an active role of the gluon component in the formation of secondaries, is indicative of the fragmentation mechanism of hadronization occurring in a vacuum, and describes experimental data on multiplicity distributions. [ABSTRACT FROM AUTHOR]

We study the strong decays of the ϕ (2170) , along with its possible partner X (2436) , as two fully strange tetraquark states of J P C = 1 − − . These two states are assumed to contain two strange quarks and two anti-strange quarks, with the flavor symmetry 6 s s ⊗ 6 ¯ s ¯ s ¯ . We consider seven decay channels: ϕ η , ϕ η ′ , ϕ f 0 (980) , ϕ f 1 (1420) , h 1 (1415) η , h 1 (1415) η ′ , and h 1 (1415) f 1 (1420) . Some of these channels are kinematically possible, and we calculate their relative branching ratios through the Fierz rearrangement. Future experimental measurements on these ratios could be useful in determining the nature of the ϕ (2170) and X (2436) . The ϕ (2170) has been observed in the ϕ f 0 (980) , ϕ η , and ϕ η ′ channels, and we propose to further examine it in the h 1 (1415) η channel. Evidences of the X (2436) have been observed in the ϕ f 0 (980) channel, and we propose to verify whether this structure exists or not in the ϕ η , ϕ η ′ , h 1 (1415) η , and h 1 (1415) η ′ channels. [ABSTRACT FROM AUTHOR]

Jet substructure observables hold the keys to identifying the inner working of the quark–gluon plasma through its imprints in jet modification patterns. Because of the multi-scale nature of jet evolution, the strategy has focused on developing jet reclustering-based and jet shape-based observables to specifically probe different stages of jet evolution, which provide multi-dimensional quantification of jet particle distribution phase spaces. The developments of jet substructure in the past few years allowed us to explore the correlations among jet observables. The richer information beyond single-observable modifications could give provides a crucial step beyond the energy loss paradigm. This review surveys the theory and phenomenology of modern jet substructure observables, which help constraining the energy scales of medium interactions and identifying heavy flavor quarks within jets. Also, the peculiar soft activities point to more refined studies of medium responses to jets. [ABSTRACT FROM AUTHOR]

We study in detail the influence of different chemical potentials (baryon, electric charge, strange, and neutrino) on how and how fast a free gas of quarks in the zero-temperature limit reaches the conformal limit. We discuss the influence of non-zero masses, the inclusion of leptons, and different constraints, such as charge neutrality, zero-net strangeness, and fixed lepton fraction. We also investigate for the first time how the symmetry energy of the system under some of these conditions approaches the conformal limit. We find that the inclusion of all quark masses (even the light ones) can produce different results depending on the chemical potential values or constraints assumed. A positive or negative deviation of 10% from the pressure of free massless quarks with the same chemical potential was found to take place as low as μ B = 77 to as high as 48 , 897 MeV. This illustrates the fact that the "free" or conformal limit is not a unique description. Finally, we briefly discuss what kind of corrections are expected from perturbative QCD as one goes away from the conformal limit. [ABSTRACT FROM AUTHOR]

Ratios ms/md and mu/md of the light quark masses have been determined from expressions for squared masses of pseudoscalar mesons and obtained with an accuracy of the second order in chiral symmetry breaking. The fit of the theoretical expressions for and to their phenomenological values leads to a functional relation between the ratios ms/md and mu/md, which is described by a third-order curve. The application of the lattice calculation result ms/mud = 27.23(10), where mud = (mu + md)/2, reported by the flavor lattice averaging group (FLAG) for the case of four quark flavors provides an additional constraint, which significantly reduces the error (~2%) for the ratio mu/md = 0.455(8). The absolute values of the quark masses have been then obtained. [ABSTRACT FROM AUTHOR]

In this paper, we present our QCD analysis of the Nucleon Form Factors presented by JLab to extract a new parameterization for the valence Generalized Parton Distributions (GPDs), H v q (x , ξ = 0 , t) and E v q (x , ξ = 0 , t). We choose simple parameterizations for x − and t − dependence of GPDs at zero skewness. These free parameters of the model are then obtained using old and new data of nucleon's elastic electromagnetic form factors (FFs) from JLAB. We have also used the "Hessian method" to perform a careful estimation of the uncertainties for the nucleon GPDs and corresponding observables originate from experimental errors. We also calculate the parton distribution functions (PDFs) in Impact parameter space to show the 3D structure of the Nucleon. We also calculated the proton and the neutron charge densities ρ ch (p , n) . We show that there is a highly localized negative charge near the center of the neutron and it is because of the negatively charged down quarks dominating the high momentum quarks in the neutron. Finally using the obtained Dirac's FF, we had an estimation for the proton charge radius. The predictions based on the obtained nucleon GPDs are in good agreement with all available experimental data and other phenomenological models. [ABSTRACT FROM AUTHOR]

We study cold strange quark stars employing an enhanced version of the quark-mass density-dependent model, which incorporates excluded volume effects to address non-perturbative QCD repulsive interactions. We provide a comparative analysis of our mass formula parametrization with previous models from the literature. We identify the regions within the parameter space where three-flavor quark matter is more stable than the most tightly bound atomic nucleus (stability window). Specifically, we show that excluded volume effects do not change the Gibbs free energy per baryon at zero pressure, rendering the stability window unaffected. The curves of pressure versus energy density exhibit various shapes—convex upward, concave downward, or nearly linear—depending on the mass parametrization. This behavior results in different patterns of increase, decrease, or constancy in the speed of sound as a function of baryon number density. We analyze the mass–radius relationship of strange quark stars, revealing a significant increase in maximum gravitational mass and a shift in the curves toward larger radii as the excluded volume effect intensifies. Excluded volume effects render our models compatible with all modern astrophysical constraints, including the properties of the recently observed low-mass compact object HESSJ1731. [ABSTRACT FROM AUTHOR]

Partial widths and double- and single-differential distributions are calculated on the framework of the Standard Model for the four-lepton decays , where = and . The contribution of virtual-photon emission by a light quark and a heavy quark, the bremsstrahlung contribution from charged leptons in the final state, the weak-annihilation contribution, and the contribution of wide vector resonances are taken into account. The contribution of narrow and resonances is excluded. Virtual-photon emission by the light quark of a meson is described on the framework of the vector-meson-dominance model, within which only the contributions of the lightest vector mesons containing pairs are taken into account. For the meson, this is the resonance. For the meson, the contributions of the and resonances are taken into account. Two possibilities are considered in the present study. The first is that where the contributions of the narrow and mesons are excluded from the partial widths with respect to the corresponding decays. The second is that where the contributions of narrow resonances are taken into account in partial widths. The problem of the influence of the subtraction procedure on the partial widths with respect to the decays is studied individually. [ABSTRACT FROM AUTHOR]

We present a state-of-the-art calculation of the unpolarized pion valence-quark distribution in the framework of large-momentum effective theory (LaMET) with improved handling of systematic errors as well as two-loop perturbative matching. We use lattice ensembles generated by the MILC collaboration at lattice spacing a ≈ 0.09 fm, lattice volume 643 × 96, N f = 2 + 1 + 1 flavors of highly-improved staggered quarks and a physical pion mass. The LaMET matrix elements are calculated with pions boosted to momentum P z ≈ 1.72 GeV with high-statistics of O (106) measurements. We study the pion PDF in both hybrid-ratio and hybrid-regularization-independent momentum subtraction (hybrid-RI/MOM) schemes and also compare the systematic errors with and without the addition of leading-renormalon resummation (LRR) and renormalization-group resummation (RGR) in both the renormalization and lightcone matching. The final lightcone PDF results are presented in the modified minimal-subtraction scheme at renormalization scale μ = 2.0 GeV. We show that the x -dependent PDFs are compatible between the hybrid-ratio and hybrid-RI/MOM renormalization with the same improvements. We also show that systematics are greatly reduced by the simultaneous inclusion of RGR and LRR and that these methods are necessary if improved precision is to be reached with higher-order terms in renormalization and matching. [ABSTRACT FROM AUTHOR]

We suggest a simple relation between the quark and the lepton mixing within the framework of type-I seesaw mechanism. We show that within our ansatz the empirical King–Mohapatra–Smirnov relation, which suggests a connection between the CKM and PMNS mixing where | V 13 PMNS | ≈ sin θ C / 2 , can be derived. This is possible within a restricted region of the Dirac and Majorana mass parameters. [ABSTRACT FROM AUTHOR]

We review the hadronic light-by-light (HLbL) contribution to the muon anomalous magnetic moment. Upcoming measurements will reduce the experimental uncertainty of this observable by a factor of four; therefore, the theoretical precision must improve accordingly to fully harness such an experimental breakthrough. With regards to the HLbL contribution, this implies a study of the high-energy intermediate states that are neglected in dispersive estimates. We focus on the maximally symmetric high-energy regime and in-quark loop approximation of perturbation theory, following the method of the OPE with background fields proposed by Bijnens et al. in 2019 and 2020. We confirm their results regarding the contributions to the muon g − 2 . For this, we use an alternative computational method based on a reduction in the full quark loop amplitude, instead of projecting on a supposedly complete system of tensor structures motivated by first principles. Concerning scalar coefficients, mass corrections have been obtained by hypergeometric representations of Mellin–Barnes integrals. By our technique, the completeness of such kinematic singularity/zero-free tensor decomposition of the HLbL amplitude is explicitly checked. [ABSTRACT FROM AUTHOR]