Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userThe Light Baryonium Spectrum
71
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
We evaluate the light baryonium sepectrum, viz. the baryon-antibaryon states, in the framework of QCD sum rules. The non-perturbative contributions up to dimension 12 are taken into account. Numerical results indicate that there might exist 8 possible light baryonium states, i.e. $p$-$bar{p}$, $Lambda$-$bar{Lambda}$, $Sigma$-$bar{Sigma}$, and $Xi$-$bar{Xi}$ with quantum numbers of $0^{-+}$ and $1^{--}$. For the $Lambda$-$bar{Lambda}$, $Sigma$-$bar{Sigma}$, and $Xi$-$bar{Xi}$ states, their masses are found above the corresponding dibaryon thresholds, while the masses of $p$-$bar{p}$ states are not. The possible baryonium decay modes are analyzed, which are hopefully measurable in BESIII, BELLEII, and LHCb experiments.
rate research
Read More
We suggest that the recently discovered charm-strange meson D_sJ(2632), with unusual properties, could be a cyptoexotic tetraquark baryonium state cdd_bars_bar. We predict other four narrow states, as Regge recurrences of D_sJ(2632), below the possible baryon-antibaryon thresholds.
For some time, the MILC Collaboration has been studying electromagnetic effects on light mesons. These calculations use fully dynamical QCD, but only quenched photons, which suffices to NLO in XPT. That is, the sea quarks are electrically neutral, while the valence quarks carry charge. For the photons we use the non-compact formalism. We have new results with lattice spacing as small as 0.045 fm and a large range of volumes. We consider how well chiral perturbation theory describes these results and the implications for light quark masses
In this article, we construct the six-quark currents with the $J^P=0^+$, $0^-$, $1^+$ and $1^-$ to study the $Lambda_c$$Lambda_c$ dibaryon and $Lambda_c$$bar{Lambda}_c$ baryonium states via QCD sum rules. We consider the vacuum condensates up to dimension 16 and truncation of the order $mathcal{O}(alpha_s^k )$ with $kleq3$. The predicted masses are $5.11_{-0.12}^{+0.15}$GeV, $4.66_{-0.06}^{+0.10}$GeV, $4.99_{-0.09}^{+0.10}$GeV $4.68^{+0.08}_{-0.08}$GeV for the $J^P=0^+$, $0^-$, $1^+$ and $1^-$ states, respectively, which can be confronted to the experimental data in the future considering the high integrated luminosity at the center-of-mass energy about $4.8,rm{GeV}$ at the BESIII. We find the terms with $frac{3}{2}< k leq 3$ do play a tiny role, and we can ignore these terms safely in the QCD sum rules.
The quenched hadron spectrum in the continuum obtained with the Wilson quark action in recent simulations on the CP-PACS is presented. Results for the light quark masses and the QCD scale parameter are reported.
Energies for excited light baryons are computed in quenched QCD with a pion mass of 490 MeV. Operators used in the simulations include local operators and the simplest nonlocal operators that have nontrivial orbital structures. All operators are designed with the use of Clebsch-Gordan coefficients of the octahedral group so that they transform irreducibly under the group rotations. Matrices of correlation functions are computed for each irreducible representation, and then the variational method is applied to separate mass eigenstates. We obtained 17 states for isospin 1/2 and 11 states for isospin 3/2 in various spin-parity channels including $J^P=5/2^pm$. The pattern of the lowest-lying energies from each irrep is discussed. We use anisotropic lattices of volume $24^3times 64$ with temporal lattice spacing $a_t^{-1}=6.05$ GeV with renormalized anisotropy $xi=3.0$.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
