Baryon Masses in Lattice QCD with Exact Chiral Symmetry

TL;DR

This study calculates baryon masses in quenched lattice QCD with exact chiral symmetry, matching experimental data for most states and providing predictions for charmed baryons.

Contribution

It presents the first quenched lattice QCD calculations of baryon masses with exact chiral symmetry, including predictions for charmed baryons.

Findings

Baryon masses agree with experimental data for most states.

Negative parity states of Λ and Λc deviate from experiments.

Provides lattice QCD predictions for doubly- and triply-charmed baryons.

Abstract

We investigate the baryon mass spectrum in quenched lattice QCD with exact chiral symmetry. For 100 gauge configurations generated with Wilson gauge action at $ \beta = 6.1 $ on the $ 20^3 \times 40 $ lattice, we compute (point-to-point) quark propagators for 30 quark masses in the range $ 67 {MeV} \le m_q \le 1790 {MeV} $. For baryons only composed of strange and charm quarks, their masses are extracted directly from the time correlation functions, while for those containing $ u (d) $ light quarks, their masses are obtained by chiral extrapolation to $ m_\pi = 135 $ MeV. Our results of baryon masses are in good agreement with experimental values, except for the negative parity states of $ \Lambda $ and $ \Lambda_c $. Further, our results of charmed (including doubly-charmed and triply-charmed) baryons can serve as predictions of QCD.