We present results of our numerical calculation of the mass spectrum for isospin one-half and spin one-half nonstrange baryons, i.e., the ground and excited states of the nucleon, in quenched lattice QCD. We use a new lattice discretization scheme for fermions, domain wall fermions, which possess almost exact chiral symmetry at nonzero lattice spacing. We make a systematic investigation of the negative-parity N* spectrum by using two distinct interpolating operators at β=6/g2=6.0 on a 163×32×16 lattice. The mass estimates extracted from the two operators are consistent with each other. The observed large mass splitting between this state, N* (1535), and the positive-parity ground state, the nucleon N(939), is well reproduced by our calculations. We have also calculated the mass of the first positive-parity excited state and find that it is heavier than the negative-parity excited state for the quark masses studied.
|Number of pages||6705284|
|Journal||Physical Review D - Particles, Fields, Gravitation and Cosmology|
|Issue number||7 B|
|Publication status||Published - 2002 Apr 1|
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)