Excited baryons from Bayesian priors and overlap fermions

Conference · Thu May 01 04:00:00 EDT 2003

OSTI ID:824450

Lee, F X; Dong, S J; Draper, T; Horvath, I; Liu, K F; Mathur, N; Zhang, J B

Using the constrained-fitting method based on Bayesian priors, we extract the masses of the two lowest states of octet and decouplet baryons with both parities. The calculation is done on quenched 163 x 28 lattices of a = 0.2 fm using an improved gauge action and overlap fermions, with the pion mass as low as 180 MeV. The Roper state N(1440)+ is clearly observed for the first time as the 1st-excited state of the nucleon from the standard interpolating field. Together with other baryons, our preliminary results indicate that the level-ordering of the low-lying baryon states on the lattice is largely consistent with experiment. The realization is helped by cross-overs between the excited + and - states in the region of mp 300 to 400 MeV.

• Research Organization: Thomas Jefferson National Accelerator Facility, Newport News, VA (US)
• Sponsoring Organization: USDOE Office of Energy Research (ER) (US)
• DOE Contract Number: AC05-84ER40150
• OSTI ID: 824450
• Report Number(s): JLAB-THY-02-73; DOE/ER/40150-2679; hep-lat/0208070
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BARYONS
FERMIONS
LATTICE FIELD THEORY
NUCLEONS
PIONS