In-medium properties of the light and heavy-light mesons in a light-front quark model

We have presented the leading twist quark transverse momentum-dependent parton distribution functions (TMDs) for the spin-1 heavy vector mesons J/ψ-meson and ϒ-meson using the overlap of the light-front wave functions. We have computed their TMDs in the light-front holographic model (LFHM) as well as the light-front quark model (LFQM) and further compared the results with the Bethe-Salpeter (BSE) model. We have discussed the behavior of the TMDs with respect to momentum fraction carried by active quark (x) and the transverse quark momenta (k⊥) in both the models. We have also calculated the k⊥ moments of the quark in both the models and have compared the results with the BSE model. The predictions of LFQM are found to be in accord with the BSE model. Further, we have analyzed the leading twist parton distribution functions (PDFs) for both the heavy mesons in both the models and the results are found to be in accord with the basic light-front quantization (BLFQ) and BSE model. Published by the American Physical Society 2024

Leading twist T -even TMDs for the spin-1 heavy vector mesons

Puhan,

Dahiya

2024

Kaon structure in the nuclear medium within the light front approach

Yabusaki,

de Melo,

Tsushima

et al. 2024

We study the properties of the charged kaon in symmetric nuclear matter using a Bethe-Salpeter amplitude to model the quark-antiquark bound state, which is well constrained by previous studies of its vacuum properties. The electromagnetic form factor, charge radius, decay constant, and the light-front valence component probability are investigated in symmetric nuclear matter. In order to describe the constituent up and antistrange quarks in nuclear matter, we adopt the “quark-meson coupling (QMC) model,” which has been widely applied to various hadronic and nuclear phenomena in the nuclear medium. Published by the American Physical Society 2024

Structure of heavy mesons in the light-front quark model

Arifi,

Happ,

Ohno

et al. 2024

We investigate the structure of ground-state heavy mesons within the light-front quark model, utilizing wave functions derived from the single Gaussian ansatz (SGA) and the Gaussian expansion method (GEM). By performing a χ2 fit to static properties such as mass spectra and decay constants, we determine the model parameters for each approach. We then compare the impacts of both methods on the light-front wave functions and structural observables. Our analysis reveals significant differences in the distribution amplitudes ϕ2;M(x) near the end points, with GEM showing enhanced amplitudes and correct asymptotic behavior ϕ2;M(x→1)∝(1−x), consistent with perturbative QCD. This end point behavior is linked to the short-range (high-momentum) wave function governed by color Coulomb interaction and relativistic kinematics. GEM accurately reproduces a power-law damping ψ0(k→∞)∝1/k⊥2, aligning with perturbative QCD predictions. Furthermore, the electromagnetic form factors of pseudoscalar mesons in the low-Q2 region fall off faster with GEM than with SGA. Overall, while both methods adequately describe static properties, GEM provides a more accurate description of structural properties, being more sensitive to details and asymptotic behaviors. Published by the American Physical Society 2024