Nuclear Theory·nucl-th

Tuesday·April 18, 2023

11 papers—8 primary·3 cross-listed

09
Heavy baryon spectroscopy in a quark-diquark approach
A. Torcato🇵🇹 · A. Arriaga🇵🇹 · G. Eichmann🇦🇹 · M. T. Peña🇵🇹
We report progress on calculations of the heavy-light baryons $Σ_{c}$ and $Λ_{c}$ and their excitations with $J^{P} = 1/ 2^{+}$ using functional methods. We employ a covariant quark-diquark approach, where the interaction amounts to a quark exchange between quarks and diquarks and the ingredients are determined from the quark level. A partial-wave analysis reveals the presence of orbital angular momentum components in terms of p waves, which are non-relativistically suppressed.
↳ hep-phhep-latnucl-thFew Body Syst.(2023)·9 citations
10
Evidence of the Schwinger mechanism from lattice QCD
Mauricio Narciso Ferreira🇪🇸
In quantum chromodynamics (QCD), gluons acquire a mass scale through the action of the Schwinger mechanism. This mass emerges as a result of the dynamical formation of massless bound-states of gluons which manifest as longitudinally coupled poles in the vertices. In this contribution, we show how the presence of these poles can be determined from lattice QCD results for the propagators and vertices. The crucial observation that allows this determination is that the Schwinger mechanism poles induce modifications, called ``displacements'', to the Ward identities (WIs) relating two- and three-point functions. Importantly, the displacement functions correspond precisely to the Bethe-Salpeter amplitudes of the massless bound-states. We apply this idea to the case of the three-gluon vertex in pure Yang-Mills SU(3). Using lattice results in the corresponding WI, we find an unequivocal displacement and show that it is consistent with the prediction based on the Bethe-Salpeter equation.
↳ hep-lathep-phhep-thnucl-thFew Body Syst.(2023)·1 citation
11
First characterization of the scattering length distribution of vector meson interaction with deuteron
Xiao-Yun Wang🇨🇳 · Chen Dong🇨🇳 · Quanjin Wang🇨🇳
Under the framework of the vector meson dominance model (VMD), the absolute scattering lengths of light vector mesons ( $ϕ$ , $ω$ , and $ρ$ ) with the deuteron are calculated from the cross sections of vector meson photoproduction off a deuteron. Additionally, a fitting function is used to predict the scattering lengths of the heavy vector mesons $J / ψ$ - $d$ and - $d$ . Based on these results, the distribution of the scattering lengths $∣ α_{V d} ∣$ between vector mesons and the deuteron is presented for the first time and compared with the scattering lengths $∣ α_{V p} ∣$ between vector mesons and the proton. It is found that as the mass of the vector meson increases, the scattering lengths $∣ α_{V d} ∣$ become closer to $∣ α_{V p} ∣$ . In addition, the correlation analysis indicates a strong positive relationship between the scattering length and the vector meson radius, with a high correlation coefficient. The implications of results are essential for improving our understanding of the interaction between hadron and nucleus.
↳ hep-phnucl-thPRC(2023)·4 citations

Affiliations

first authorsco-authorsvia INSPIRE

Heavy baryon spectroscopy in a quark-diquark approach

Evidence of the Schwinger mechanism from lattice QCD

First characterization of the scattering length distribution of vector meson interaction with deuteron

Affiliations