Speaker
Description
In this work, we aim to calculate the diquark mass together with the quark-diquark potential in which we apply an extended HAL QCD potential method to a baryonic system made up from a static quark and a diquark. We consider various types of diquarks
(eg: scalar $0^{+}$ diquark, axial-vector $1^{+}$ diquark etc) to examine their mass differences.
Numerical calculations are performed by employing 2 + 1 flavor QCD gauge configurations generated by PACS-CS Collaborations on a $L^3$ \times T = $ 32^3 \times 64$ lattice with $m_{\pi} \sim$ 700 MeV.
To improve the statistical noise in the static quark propagators, we also employ the HYP smearing on the gauge links.
Two-point correlators of quark-diquark baryonic system are then computed to obtain their ground-state energies and mass differences.
For the baryonic system made up from a scalar diquark and a static quark, we apply an extended HAL QCD method to study the scalar diquark mass and the quark-diquark potential where, in order to determine the diquark mass self-consistently in the HAL QCD method, we demand that the baryonic spectrum in the p-wave sector should be reproduced by the potential obtained from the baryonic system in the s-wave sector.
We obtain the scalar diquark mass of roughly (2/3) $m_{N}$, i.e., twice the naïve estimates of a constituent quark mass together with the quark-diquark potential of Cornell type (Coulomb + linear).
