In this article, we calculate the mass shift and decay constant of isospin averaged pseudoscalar ($D^+$,$D^0$) and scalar ($D^+_0$,$D^0_0$) mesons by the magnetic field induced quark and gluon condensates at finite density and temperature of asymmetric nuclear matter. We have calculated the in-medium chiral condensates from the chiral SU(3) mean field model and subsequently used these condensates in QCD Sum Rules (QCDSR) to calculate the effective mass and decay constant of $D$ mesons. Consideration of external magnetic field effects in hot and dense nuclear matter lead to appreciable modification in the masses and decay constants of $D$ mesons. Furthermore, we also studied the effective decay width of higher charmonium states ($ψ(3686),ψ(3770),{{χ_c}_0}(3414),{{χ_c}_2}(3556)$) as a by-product by using $^3P_0$ model which can have an important impact on the yield of $J/ψ$ mesons. The results of present work will be helpful to understand the experimental observables of the heavy ion colliders which aim to produce matter at finite density and moderate temperature.
Masses of the pseudoscalar $(J^{PC}=0^{-+})$ charmonium and bottomonium hybrids are determined using QCD Laplace sum-rules. The effects of the dimension-six gluon condensate are included in our analysis and result in a stable sum-rule analysis, whereas previous studies of these states were unable to optimize mass predictions. The pseudoscalar charmonium hybrid is predicted to have a mass of approximately 3.8 GeV and the corresponding bottomonium prediction is 10.6 GeV. Calculating the full correlation function, rather than only the imaginary part, is shown to be necessary for accurate formulat…
In this article, we investigate the structures of the pseudoscalar charmonium and bottomonium in the framework of the coupled rainbow Schwinger-Dyson equation and ladder Bethe-Salpeter equation with the confining effective potential (infrared modified flat bottom potential). As the current masses are very large, the dressing or renormalization for the $c$ and $b$ quarks are tender, however, mass poles in the timelike region are absent. The Euclidean time fourier transformed quark propagator has no mass poles in the timelike region which naturally implements confinement. The Bethe-Salpeter wave…
We apply hard pion Chiral Perturbation Theory to charmonium decays to $ππ$, $KK$ and $ηη$. We first discuss why we expect to be able to provide results for the chiral logarithms in $χ_{c0}$ and $χ_{c2}$ decays to two pseudoscalars while for the decays from $J/ψ$, $ψ(nS)$ and $χ_{c1}$ no simple prediction is possible. The leading chiral logarithm turns out to be absent for $χ_{c0},χ_{c2}\to PP$. This result is true for all fully chiral singlet states of spin zero and two.
The effective interaction of a pseudoscalar particle with photon in plasma with the presence of a constant uniform magnetic field is investigated. It is shown that under some physical conditions the effective coupling between pseudoscalar particle and photon does not depend on medium parameters and particles momentum. The probability of the familon decay into photon pair in a strongly magnetized degenerate ultrarelativistic plasma is calculated.
In this work we calculate the mass spectrum, weak decay constants, two photon decay widths, and two gluon decay widths of ground (1S), and radially excited (2S,3S,...) states of pseudoscalar charmoniuum and bottomonium such as $η_{c}$ and $η_{b}$, as well as the mass spectrum and leptonic decay constants of ground state (1S), excited (2S,1D,3S,2D,4S,and 3D) states of vector charmonium and bottomonium such as $J/ψ$, and $Υ$, using the formulation of Bethe-Salpeter equation under covariant Instantaneous Ansatz (CIA). Our results are in good agreement with data (where ever available) and other mo…
The radiative and leptonic decays of $η_c\to γγ$ and $η_c\to l^+l^-$ are studied. For $η_c\to γγ$ decay, the second-order electromagnetic tree-level diagram gives the leading contribution. The decay rate of $η_c\to γγ$ is calculated, the prediction is in good agreement with the experimental data. For $η_c\to l^+ł^-$, both the tree and loop diagrams are calculated. The analysis shows that the loop contribution dominates, the contribution of tree diagram with $Z^0$ intermediate state can only modifies the decay rate by less than 1%. The prediction of the branching ratios of $η_c\to e^+e^-$ and $…
We use QCD sum-rules to predict ground state masses for pseudoscalar ($J^{PC}=0^{-+}$) charmonium and bottomonium hybrids. We find that the inclusion of a six-dimensional gluon condensate contribution is needed to stabilize the analyses. For the charmonium hybrid, we find a mass of $(3.82\pm0.13)$ GeV; for the bottomonium hybrid, we find a mass of $(10.64\pm0.19)$ GeV. We comment on possible phenomenological implications concerning the Y(3940).
In this work we study the radiative decay widths of vector quarkonia for the process of $J/ψ(nS)\rightarrowη_{c}(nS)γ$ and $Υ(nS)\rightarrowη_{b}(nS)γ$ (for principal quantum numbers $n=1, 2, 3$) in the framework of Bethe-Salpeter equation under the covariant instantaneous ansatz using a $4\times 4$ form of BSE. The parameters of the framework were determined by a fit to the mass spectrum of ground states of pseudoscalar and vector quarkonia, such as; $η_{c}$, $η_{b}$, $J/ψ$ and $Υ$. These input parameters so fixed were found to give good agreements with data on mass spectra of ground and exci…
We study instanton contributions to hadronic decays of the scalar glueball, the pseudoscalar charmonium state $η_c$, and the scalar charmonium state $χ_c$. Hadronic decays of the $η_c$ are of particular interest. The three main decay channels are $K\bar{K}π$, $ηππ$ and $η'ππ$, each with an unusually large branching ratio $\sim 5%$. On the quark level, all three decays correspond to an instanton type vertex $(\bar{c}c)(\bar{s}s)(\bar{d}d)(\bar{u}u)$. We show that the total decay rate into three pseudoscalar mesons can be reproduced using an instanton size distribution consistent with phenomenol…
We investigate the masses of the pseudoscalar ($D$($D^0$, $D^+$), $\bar{D}$($\bar{D^0}$, $D^-$) and vector open charm mesons ($D^*$($D^{*0}$, $D^{*+}$), ${\bar{D}}^*$(${\bar{D}}^{*0}$, $D^{*-}$) as well as the pseudoscalar ($η_c(1S)$, $η_c(2S)$) and the vector charmonium states ($J/ψ$, $ψ(2S)$, $ψ(1D)$) in the asymmetric hot strange hadronic medium in the presence of strong magnetic fields. In the magnetized medium, the mass modification of open charm mesons due to their interactions with baryons and the scalar fields ($σ$, $ζ$, and $δ$) are investigated in a chiral effective model. Moreover, …
We study the partial decay widths of the charmonium states ($J/ψ$, $ψ(3686)$, $ψ(3770)$, $χ_{c0}$, $χ_{c2}$) to $D\bar D$ ($D^+D^-$ or $D^0\bar {D^0}$) in isospin asymmetric nuclear matter, in the presence of strong magnetic fields. The in-medium partial decay widths of charmonium states to $D\bar D$ are calculated within a light quark--antiquark pair creation model, namely the $^3P_0$ model, using the in--medium masses of the charmonia as well as $D$ and $\bar D$ mesons in the magnetized nuclear matter obtained within a chiral effective model. The presence of a magnetic field leads to Landau …
We study the vacuum properties of the pseudoscalar glueball and charmed mesons by using the so-called extended Linear Sigma Model (eLSM). This model includes scalar and pseudoscalar mesons, as well as vector and axial-vector mesons. We calculate the mesonic and baryonic decays of the pseudoscalar glueball, where we fixed its mass to $2.6$ GeV, as predicted by lattice-QCD simulations, and take a closer look at the scalar-isoscalar decay channel. As a second step, we enlarge the so-called extended linear Sigma model (eLSM) by including the charm quark to a global $U(4)_r\times U(4)_l$ chiral sym…
Using QCD sum rules and chiral SU(3) model, we investigate the effect of temperature, density, strangeness fraction and isospin asymmetric parameter on the shift in masses and decay constants of the pseudoscalar $D$ and $B$ meson in hadronic medium, which consist of nucleons and hyperons. The in-medium properties of $D$ and $B$ mesons within QCD sum rule approach depend upon the quark and gluon condensates. In chiral SU(3) model, quark and gluon condensates are introduced through the explicit symmetry breaking term and the trace anomaly property of the QCD, respectively and are written in term…
In this paper the production of excited vector and pseudoscalar charmonium mesons in $\epem$ annihilation is analyzed in the framework of light cone. In particular the cross sections $\epem \to ψ(2S)η_c(1S), ψ(1S)η_c(2S),ψ(2S)η_c(2S)$ have been calculated. It is shown, that contrary to NRQCD the cross sections calculated in the framework of light cone agree with experimental data.
The role of higher Fock-state contributions to exclusive charmonium decays will be discussed. It will be argued that the J/Psi (Psi') decays into baryon-antibaryon pairs are dominated by the valence Fock-state contributions. P-wave charmonium decays, on the other hand, receive strong contributions from the c cbar g Fock states since the valence Fock-state contributions are suppressed in these reactions. Numerical results for the decay widths of J/Psi (Psi') into baryon-antibaryon and chi(J) into pairs of pseudoscalar mesons will be also presented and compared to data.
In the fractional nonrelativistic potential model, the decomposition of heavy quarkonium in a hot magnetized medium is investigated. The analytical solution of the fractional radial Schrodinger equation for the hot-magnetized interaction potential is displayed by using the conformable fractional Nikiforov-Uvarov method. Analytical expressions for the energy eigenvalues and the radial wave function are obtained for arbitrary quantum numbers. Next, we study the charmonium and bottmonium binding energies for different magnetic field values in the thermal medium. The effect of the fractional param…
The mass spectra of charmonium are investigated using a Coulomb plus linear (Cornell) potential. Gaussian wave function in position space as well as in momentum space are employed to calculate the expectation value of potential and kinetic energy respectively. Various experimental states ($X(4660)(5^{3}S_{1})$, $X(3872)(2^{3}P_{1})$, $X(3900)(2^{1}P_{1})$, $X(3915)(2^{3}P_{0})$ and $X(4274)(3^{3}P_{1})$ etc.) are assigned as charmonium states. We also study the Regge trajectories, pseudoscalar and vector decay constants, the Electric and Magnetic dipole transition rates and the annihilation de…
The masses and decay widths of charmonium states are studied in the presence of strong magnetic fields. The mixing between the pseudoscalar and vector charmonium states at rest is observed to lead to appreciable negative (positive) shifts in the masses of the pseudoscalar (longitudinal component of the vector) charmonium states in vacuum/hadronic medium in the presence of high magnetic fields. The pseudoscalar and vector charmonium masses in the hadronic medium, calculated in an effective chiral model from the medium changes of a scalar dilaton field, have additional significant modifications …
In many extentions of standard model, dimension-5 scalar di-photon ($g_{γγϕ}ϕ$ $F^{μν}F_{μν}$ ) or pseudoscalar di-photon ($g_{γγa}a\tilde{F}^{μν} F_{μν} $, ) interaction materializes due to scale symmetry breaking or $U_A(1)$ symmetry breaking. In a magnetized vacuum (i.e., in an external background field $\bar{F}_{μν} $) the transverse degrees of freedom of the photons-- for such systems-- can be described in terms of the form factors constructed out of the background field strength tensor ($\bar{F}_{μν} $) and the same for dynamical photon ($f^{μν}$); they happen to be $\bar{F}_{μν}f^{μν}$ …
The study of electron-positron collisions at center-of-mass energies corresponding to charmonium production has reached new levels of sensitivity thanks to experiments by the BES and CLEO Collaborations. Final states $γP$, where $P$ is a pseudoscalar meson such as $π^0$, $η$, and $η'$ can arise either from charmonium decays or in the continuum through a virtual photon: $e^+ e^- \to γ^* \to γP$. Estimates of this latter process are given at center-of-mass (c.m.) energies corresponding to the $J/ψ(1S)$, $ψ(2S)$, and $ψ(3770)$ resonances.
Following the observation of the fully-heavy tetraquark candidates $X(6900)$ and possible $X(6300)$ in the di-$J/ψ$ spectrum by the LHCb Collaboration, we investigate the near-threshold dynamics of the pseudoscalar quarkonium pairs in a coupled-channel approach in the di-$η_c$ channel. We show that the Pomeron exchange mechanism should be a general dynamics in the near-threshold heavy quarkonium pair interactions. In the di-$η_c$ channel, a coupled-channel system involving the di-$η_c$, $η_c$-$η_c(2S)$ and di-$η_c(2S)$ interactions can be established. Their $S$-wave interactions near threshold…
We discuss the partial width of the pseudoscalar charmonium state eta_c and bottomonium state eta_b into two photons. Predictions from potential models are examined and compared with experimental values for the eta_c case. Through the NRQCD factorisation procedure results for eta_c are also compared with those from J/psi data, and results for eta_b to the Upsilon decay data.
In this article, we study the pseudoscalar bound state $η_c'f_0(980)$ (irrespective of the hadro-charmonium and the molecular state) with the QCD sum rules. Considering the SU(3) symmetry of the light flavor quarks and the heavy quark symmetry, we also study the bound states $η_c'σ(400-1200)$, $η_b'''f_0(980)$ and $η_b'''σ(400-1200)$, and make reasonable predictions for their masses.
We study three different chiral Lagrangians that describe the two- and three-body decays of an excited pseudoscalar glueball, $J^{PC}=0^{*-+}$, into light mesons and charmonium states as well as into a scalar and pseudoscalar glueball. We compute the decay channels for an excited pseudoscalar glueball with a mass of $3.7$ GeV and consider a ground state pseudoscalar glueball of mass $2.6$ GeV, following predictions from lattice QCD simulations. These states and channels are in reach of the ongoing BESIII experiment and the PANDA experiments at the upcoming FAIR facility experiment. We present …
We present the semileptonic decay of $B_{c}$ meson in a QCD potential model with the coulombic part of the Cornell potential $-\frac{4α_{S}}{3r}+br+c$ as perturbation. Computing the slope and curvature of Isgur Wise function in this approach, we study the pseudoscalar and vector form factors for the transition of $B_{c}$ meson to its S wave charmonium $c\bar{c}$ states. Numerical estimates of widths for the transitions of $B_{c}\rightarrow J/ψ(η_{c})lν_{l}$ are presented. The results are found to be in good agreement with other theoretical values.
We investigate the mass-shift of $P$-wave charmonium (${χ_c}_0$, ${χ_c}_1$) and $S$ and $P$-wave bottomonium ($η_b$, $Υ$, ${χ_b}_0$ and ${χ_b}_1$) states in magnetized hot asymmetric nuclear matter using the unification of QCD sum rules (QCDSR) and chiral $SU(3)$ model. Within QCDSR, we use two approaches, $i.e.$, moment sum rule and Borel sum rule. The magnetic field induced scalar gluon condensate $\left\langle \frac{α_{s}}π G^a_{μν} {G^a}^{μν} \right\rangle$ and the twist-2 gluon operator $\left\langle \frac{α_{s}}π G^a_{μσ} {{G^a}_ν}^σ \right\rangle $ calculated in chiral $SU(3$) model are…
We study the phenomenology of the ground-state (pseudo-)scalar charmonia $η_c$ and $χ_{c0}$ in the framework of a $U(4)_r \times U(4)_l$ symmetric linear sigma model with (pseudo-)scalar and (axial-) vector mesons. Based on previous results for the spectrum of charmonia and the spectrum and (OZI-dominant) strong decays of open charmed mesons, we extend the study of this model to OZI-suppressed charmonia decays. This includes decays into 'ordinary' mesons but also particularly interesting channels with scalar-isoscalar resonances $f_0(1370),\, f_0(1500),\, f_0(1710)$ that may include sizeable c…
The decay widths of the charmonium states to $D\bar D$ in isospin asymmetric nuclear matter in the presence of a magnetic field are studied, using a field theoretical model for composite hadrons with quark/antiquark constituents. The medium modifications of these partial decay widths arise due to the changes in the masses of the decaying charmonium state and the produced $D$ and $\bar D$ mesons in the magnetized hadronic matter, calculated within a chiral effective model. The decay widths are computed using the light quark--antiquark pair creation term of the free Dirac Hamiltonian in terms of…
By analyzing existing data on pseudoscalar charmonium decays, we obtain the ratio of the branching fractions of $η_c(2S)$ and $η_c$ decays into ten different final states with light hadrons. For the first time, we test the two existing theoretical predictions of these decays, and find that the experimental data are significantly different from both of them. The lack of observation of any decay mode with higher rate in $η_c(2S)$ than in $η_c$ decays suggests very unusual decay dynamics in pseudoscalar charmonium decays to be identified. We also report the first model-independent evaluation of t…
We suggest a rigorous generalization of the pseudoscalar mesons mixing description in SU(3) basis. It is shown that the appearance of extra massive state nicknamed in the paper as glueball is unavoidable in any scheme with more than one angle. In this framework we develop the dispersive approach to Abelian axial anomaly of isoscalar non-singlet current. Combining it with the analysis of experimental data of charmonium radiative decays ratio we get the number of quite strict constraints for mixing parameters. Our analysis favors the equal values of axial currents coupling constants which may be…
We include the $η_c$ meson into the $η$-$η'$-$G$ mixing formalism constructed in our previous work, where $G$ represents the pseudoscalar gluball. The mixing angles in this tetramixing matrix are constrained by theoretical and experimental implications from relevant hadronic processes. Especially, the angle between $η_c$ and $G$ is found to be about $11^\circ$ from the measured decay widths of the $η_c$ meson. The pseudoscalar glueball mass $m_G$, the pseudoscalar densities $m_{qq,ss,cc}$ and the U(1) anomaly matrix elements associated with the mixed states are solved from the anomalous Ward i…
Strong decays of the charmonium-like state $Y(4320)$ have been studied in the framework of the covariant confined quark model. The resonance $Y$ has been interpreted as a four-quark state of the molecular type. We evaluate the hidden-charm decay width of $Y$ to a vector and a scalar, with the latter decaying subsequently to a pair of charged pseudoscalar states. The strong decay modes $Y \!\to\! π^{+}π^{-}J/Ψ$ and $Y \!\to\! K^{+}K^{-} J/Ψ$ have been studied by involving the scalar resonance state $f_0(980)$. We have calculated the fractal widths of the related strong decays and the branching …
Axions are pseudo-scalar particles, those arise because of breaking of Peccei Queen (PQ) symmetry. Axions have a tree level coupling to two photons. As a consequence there exists a tree level coupling of axion to photon in a magnetic field. However, in an external magnetic field, there exists a new loop induced, axion photon vertex, that gives rise to axion photon coupling. The strength of the tree level axion photon coupling in magnetic field is known to be model dependent. However in a magnetic field, the new loop induced coupling has some interesting features. This note discusses the new ax…
The exclusive decay of $Υ$ to a vector plus pseudoscalar charmonium is studied in perturbative QCD. The corresponding branching ratios are predicted to be of order $10^{-6}$ for first three $Υ$ resonances, and we expect these decay modes should be discovered in the prospective high-luminosity $e^+e^-$ facilities such as super $B$ experiment. As a manifestation of the short-distance loop contribution, the relative phases among strong, electromagnetic and radiative decay amplitudes can be deduced. It is particularly interesting to find that the relative phase between strong and electromagnetic a…
In this work the analysis of mixing parameters of the system involving eta, eta' mesons and some third massive state G is carried out. We use the generalized mixing scheme with three angles. The framework of the dispersive approach to Abelian axial anomaly of isoscalar non-singlet current and the analysis of experimental data of charmonium radiative decays ratio allow us to get a number of quite strict constraints for the mixing parameters. The analysis shows that the equal values of axial current coupling constants f_8 and f_0 are preferable which may be considered as a manifestation of SU(3)…
We have computed branching ratios of two-body nonleptonic B_c \to X_{c\bar{c}}M decays, where X_{c\bar{c}} is the radially excited charmonium η_c(2S) or ψ(2S) meson, and M is a pseudoscalar (P) or a vector (V) or an axial-vector (A(^3P_1)) meson. We have assumed factorization hypothesis and calculated the form factors in the nonrelativistic ISGW2 quark model. We have found that some of these decays have branching ratios of the order of 10^{-3} - 10^{-4}.
Charmonium sum rules for pseudoscalar 0^{-+} state eta_c(1S) are analyzed within perturbative QCD and Operator Product Expansion. The perturbative part of the pseudoscalar correlator is considered at alpha_s^2 order and the contribution of the gluon condensate <G^2> is taken into account with alpha_s correction. The OPE series includes the operators of dimension D=6,8 computed both in the instanton and factorization model. The method of moments in MS-bar scheme allows to establish acceptable values of the charm quark mass and gluon condensate, using the experimental mass of eta_c. In result of…
We calculate the spectral function in pseudoscalar (scalar) channel in the high temperature phase of QCD in presence of a background magnetic field. Spatial and temporal screening masses are determined from the long distance behavior of the corresponding correlation functions.
In this paper we study the semileptonic decays of the $B_c$ meson in the Light-Cone Sum Rule (LCSR) approach. The result for each channel depends on the corresponding distribution amplitude of the final meson. For the case of $B_c$ decaying into a pseudoscalar meson, to twist-3 accuracy only the leading twist distribution amplitude (DA) is involved if we start from a chiral current. If we choose a suitable chiral current in the vector meson case, the main twist-3 contributions are also eliminated and we can consider the leading twist contribution only. The leading twist distribution amplitudes…
Pseudoscalar particles, with almost zero mass and very weak coupling to the visible matter, arise in many extensions of the standard model of particle physics. Their mixing with photons in the presence of an external magnetic field leads to many interesting astrophysical and cosmological consequences. This mixing depends on the medium properties, the momentum of the photon and the background magnetic field. Here we give a general treatment of pseudoscalar-photon oscillations in a background magnetic field, taking the Faraday term into account. We give predictions valid in all regimes, under th…
The $J/ψπ\to \bar{D} D^*, \bar{D} D$, ${\bar D}^* D^*$ and ${\bar D} D^*$ cross sections as a function of $\sqrt{s}$ are evaluated in a QCD sum rule calculation. We study the Borel sum rule for the four point function involving pseudoscalar and vector meson currents, up to dimension four in the operator product expansion. We find that our results are smaller than the $J/ψπ\to {charmed mesons}$ cross sections obtained with models based on meson exchange, but are close to those obtained with quark exchange models.
We study the charmonium spectrum including higher spin and gluonic excitations. We determine an upper limit on the mixing of the eta_c ground state with light pseudoscalar flavour-singlet mesons and investigate the mixing of charmonia near open charm thresholds with pairs of (excited) D and anti-D mesons. For charm and light valence quarks and nF=2 sea quarks, we employ the non-perturbatively improved Sheikholeslami-Wohlert (clover) action. Excited states are accessed using the variational technique, starting from a basis of suitably optimised operators. For some aspects of this study, the use…
We argue that charmonium decays into meson pairs fall into two distinct classes: one that is under control of perturbative QCD and another one that is governed by a soft mechanism. We concentrate on a systematic analysis of J/Psi (Psi') decays into a light pseudoscalar and a light vector meson and eta(c) decays into a pair of light vector mesons. These processes belong to the second class and are characterized by non-conserved hadronic helicity. It is assumed that, in these cases, the charmonium state decays dominantly through a light-quark Fock component by a soft mechanism which is character…
Inspired by the recent measurement of the ratio of $B_c$ branching fractions to $J/ψπ^+$ and $J/ψμ^+ν_μ$ final states at the LHCb detector, we study the semileptonic decays of $B_c$ meson to the S-wave ground and radially excited 2S and 3S charmonium states with the perturbative QCD approach. After evaluating the form factors for the transitions $B_c\rightarrow P,V$, where $P$ and $V$ denote pseudoscalar and vector S-wave charmonia, respectively, we calculate the branching ratios for all these semileptonic decays. The theoretical uncertainty of hadronic input parameters are reduced by utilizin…
We investigate the in-medium masses of open charm mesons ($D$($D^0$, $D^+$), $\bar{D}$($\bar{D^0}$, $D^-$), $D_s$(${D_{s}}^+$, ${D_{s}}^-$)) and charmonium states ($J/ψ$, $ψ(3686)$, $ψ(3770)$, $χ_{c0}$, $χ_{c2}$) in strongly magnetized isospin asymmetric strange hadronic matter using a chiral effective model. In the presence of the magnetic field, the number density and scalar density of charged baryons have contributions from Landau energy levels. The mass modifications of open charm mesons arise due to their interactions with nucleons, hyperons, and the scalar fields (the non-strange field $…
The narrow charmonium state near 3872 MeV reported by the Belle collaboration and confirmedby CDF lies almost exactly at the neutral D anti-D* threshold. As was predicted many years ago it can be a deuteronlike meson-meson state called a deuson. If so, it should be an axial, or possibily a pseudoscalar state with C=0, and isospin predominantly 0. Large isospin breaking is expected because of the isospin mass splitting between the neutral and charged D (D*) mesons. Because of this large isospin breaking the decay X(3872) to J/psi rho would be allowed, while J/psi sigma would be forbidden by C-p…
Two-photon decay rates of pseudoscalar, scalar and tensor states of charmonium and bottomonium are calculated in the framework of the relativistic quark model. Both relativistic effects and one-loop radiative corrections are taken into account. The obtained results are compared with other theoretical predictions and available experimental data.
We present the quarkonia correlators for charmonium and bottomonium systems in the pseudoscalar, vector and scalar channels. For the description of quark-antiquark interaction we adopt the temperature dependant colour screening potential of the power law form. The spectroscopic parameters defined from the model are employed in the spectral functions to compute the quarkonia correlators. We find considerable medium modifications to the effective masses of the quarkonia as well as in the behaviour of the respective radial wave functions. These modifications are then reflected in the computed cor…