In-medium decay widths of hidden and open charm vector mesons in a field theoretic model for composite hadrons

Abstract

We calculate the decay widths of the charmonium states, J/ψ, ψ(3686) and ψ(3770), to DD pairs, as well as the decay width of D * → Dπ, in isospin asymmetric strange hadronic matter, using a field theoretical model for composite hadrons with quark constituents. For this purpose we use the quark antiquark pair creation term of the free Dirac Hamiltonian written in terms of the constituent quark field operators, and use explicit charmonium, D,D, D * and π states to evaluate the matrix elements for the charmonium as well as D * decay amplitudes. The medium modifications of the partial decay widths of charmonium to DD pair, arising from the mass modifications of the D(D) and the charmonium states calculated in a chiral effective model, are also included. The results of the present investigations are then compared with the decay widths computed earlier, in a model using light quark pair creation in 3 P 0 state. As in 3 P 0 model, the decay amplitude in the present model is multiplied with a strength parameter for the light quark pair creation, which is fitted from the observed vacuum decay width. The effects of the isospin asymmetry, the strangeness fraction of the hadronic matter on the masses of the charmonium states and D(D) mesons and hence on the decay widths, have also been studied. The isospin asymmetry effect is observed to be dominant for high densities, leading to appreciable difference in the decay channels of the charmonium to D + D − and D 0D0 pairs. The decay width of D * → Dπ in the hadronic matter has also been calculated within the composite quark model in the present work, accounting for the medium modifications of the D and D * masses. The density modifications of the charmonium states and D(D * ) mesons, which are observed to be appreciable at high densities, will be of relevance in the compressed baryonic matter (CBM) experiments at the future facility of FAIR, GSI, where charmed hadrons will be produced by annihilation of antiprotons on nuclei. The interactions of the charmonium states and D(D * ) with the nuclear medium could lead to the possiblility of the formation of exotic bound states of the nuclei with the (excited) charmonium states as well as with D(D

Charmonia decay widths in magnetized matter using a model for composite hadrons

“…[29], where the partial [18, 21, 29] (see Appendix B). In the absence of a magnetic field, the charmonium decay widths to D D have been studied using the model for composite hadrons as used in the present work [28]. It was observed that the decay of J/ψ to D D is possible, for densities higher than 4-4.5ρ 0 , for zero magnetic field.…”

Charmonia decay widths in magnetized matter using a model for composite hadrons

“…[29], where the partial [18, 21, 29] (see Appendix B). In the absence of a magnetic field, the charmonium decay widths to D D have been studied using the model for composite hadrons as used in the present work [28]. It was observed that the decay of J/ψ to D D is possible, for densities higher than 4-4.5ρ 0 , for zero magnetic field.…”

Open charm mesons and charmonia in magnetized strange hadronic matter *

“…The value of the mass of the charm quark is set as GeV in this investigation. Such a choice can reproduce the mass difference of the charmonium states and in a vacuum [82,83]. In this investigation, the wave functions of the charmonium states are considered to be harmonic oscillator wave functions.…”

“…The values of the parameter β, which characterizes the strength of the harmonic potential (in GeV) for , , and are 0.51, 0.38, and 0.37, respectively. They are calculated using the mean square radii of these charmonium states, which assume the values of , , and , respectively [82,83]. For the and states, the values of β in GeV are determined as 0.44 and 0.41 using the linear extrapolation of the vacuum mass versus β graph of the charmonium states , , and [94].…”

Open charm and charmonium states in strong magnetic fields

“…In the present work, we investigate the effects of the magnetic field on the decay widths constituents to be the mass (energy) of the heavy flavour meson. The value of λ 2 is calculated to be 0.85 [39], by assuming the binding energy of the hadron as shared by the quark (antquark) to be inversely proportional to the quark (antiquark) mass [37]. The harmonic oscillator strength D + and longitudinal component of the D * + due to the pseudoscalar-vector meson mixing in the presence of the magnetic field.…”

Charmonia decay widths in magnetized matter using a model for composite hadrons

“…[29], where the partial [18, 21, 29] (see Appendix B). In the absence of a magnetic field, the charmonium decay widths to D D have been studied using the model for composite hadrons as used in the present work [28]. It was observed that the decay of J/ψ to D D is possible, for densities higher than 4-4.5ρ 0 , for zero magnetic field.…”

Open charm mesons and charmonia in magnetized strange hadronic matter *

“…The value of the mass of the charm quark is set as GeV in this investigation. Such a choice can reproduce the mass difference of the charmonium states and in a vacuum [82,83]. In this investigation, the wave functions of the charmonium states are considered to be harmonic oscillator wave functions.…”

“…The values of the parameter β, which characterizes the strength of the harmonic potential (in GeV) for , , and are 0.51, 0.38, and 0.37, respectively. They are calculated using the mean square radii of these charmonium states, which assume the values of , , and , respectively [82,83]. For the and states, the values of β in GeV are determined as 0.44 and 0.41 using the linear extrapolation of the vacuum mass versus β graph of the charmonium states , , and [94].…”

Open charm and charmonium states in strong magnetic fields

“…In the present work, we investigate the effects of the magnetic field on the decay widths constituents to be the mass (energy) of the heavy flavour meson. The value of λ 2 is calculated to be 0.85 [39], by assuming the binding energy of the hadron as shared by the quark (antquark) to be inversely proportional to the quark (antiquark) mass [37]. The harmonic oscillator strength D + and longitudinal component of the D * + due to the pseudoscalar-vector meson mixing in the presence of the magnetic field.…”

Charmonia decay widths in magnetized matter using a model for composite hadrons

“…[29], where the partial [18, 21, 29] (see Appendix B). In the absence of a magnetic field, the charmonium decay widths to D D have been studied using the model for composite hadrons as used in the present work [28]. It was observed that the decay of J/ψ to D D is possible, for densities higher than 4-4.5ρ 0 , for zero magnetic field.…”

Open charm mesons and charmonia in magnetized strange hadronic matter *

“…The value of the mass of the charm quark is set as GeV in this investigation. Such a choice can reproduce the mass difference of the charmonium states and in a vacuum [82,83]. In this investigation, the wave functions of the charmonium states are considered to be harmonic oscillator wave functions.…”

“…The values of the parameter β, which characterizes the strength of the harmonic potential (in GeV) for , , and are 0.51, 0.38, and 0.37, respectively. They are calculated using the mean square radii of these charmonium states, which assume the values of , , and , respectively [82,83]. For the and states, the values of β in GeV are determined as 0.44 and 0.41 using the linear extrapolation of the vacuum mass versus β graph of the charmonium states , , and [94].…”

Open charm and charmonium states in strong magnetic fields

“…In the present work, we investigate the effects of the magnetic field on the decay widths constituents to be the mass (energy) of the heavy flavour meson. The value of λ 2 is calculated to be 0.85 [39], by assuming the binding energy of the hadron as shared by the quark (antquark) to be inversely proportional to the quark (antiquark) mass [37]. The harmonic oscillator strength D + and longitudinal component of the D * + due to the pseudoscalar-vector meson mixing in the presence of the magnetic field.…”