Improved prediction of the mass splitting for -wave baryons

Su, N.*; Chen, H.-X.*; Gubler, P. ; Hosaka, Atsushi

Using the QCD sum rule method, we investigate the mass splitting for the spin-orbit partner states of the baryon assuming that it is a -wave excitation with . This study is an extension of a previous work, in which the masses of these states were estimated with uncertainties too large to extract the reliable mass splitting. In the present study, by directly formulating a sum rule for the mass splitting, we obtain an improved prediction, MeV. This result provides a more quantitative insight into the spectrum of -wave baryons and serves as a useful reference for future experiments.