cmcneile's baryon [5 articles]

Abstract

The isotriplet Sigmac(2800) baryon with possible quantum numbers J(P) = 3/2(-), 3/2(+) is considered as a hadronic molecule composed of a nucleon and a D meson. We determine the strong two-body decay widths Sigmac to Lambdac + pi which are consistent with current data for J(P) = 3/2(-). ...

Abstract

In recent lattice QCD studies, the Feynman-Hellmann theorem is often used to estimate separate contributions of the connected and disconnected diagrams to the nucleon sigma term. We demonstrate through a simple analysis within an effective model of QCD why this could be dangerous although the theorem is naturally expected to hold for the sum of the two contributions, i.e. the net nucleon sigma term. ...

Abstract

We review recent developments in the study of excited baryon spectroscopy in lattice QCD. After introducing the basic methods used to extract masses from correlation functions, we discuss various interpolating fields and lattice actions commonly used in the literature. We present a survey of results of recent calculations of excited baryons in quenched QCD, and outline possible future directions in the study of baryon spectra. ...

Abstract

We compute the masses of the ground state baryons and their spin excited states discussing quark wave functions in baryons. Doubly charmed baryon masses are given in the expected accuracy of ±10 MeV. ...

Abstract

An analysis of the contributions of sea and valence quark masses to the signal-to-noise ratio in numerical computations of baryon correlation functions in lattice QCD is performed. It is found that lowering the sea quark mass improves the signal-to-noise. An optimized approach to the physical point in the m_ss vs. m_vv plane is proposed, and a full analysis of the cost benefit is performed. Improvements of ~ 10^(2(A-1)), where A is the number of nucleons in the system, are shown to be possible. ...