# Measuring Baryon Spectra

Research Field:

Mathematics
Resource Type:

Compute
Resource Class:

C
Lead PI:

Dr. Sinead Ryan
Abstract:

Quantum chromodynamics describes the strong interaction of quarks and gluons in particle physics. Quantum chromodynamics can be simulated on a discrete 4-D spacetime lattice using high performance computers. Various physical observables such as particle masses can be measured using lattice QCD. There are six different flavours of quark: up, down, charm, strange, top and bottom. The up, down and charm quarks have masses lower than the strange, top and bottom quarks. In this project, the mass spectra of baryons containing one bottom quark and two light quarks is calculated. Large sets of operators which create and annihilate baryons with fixed quantum numbers such as isospin, charge, parity and spin are formed. On the lattice it is difficult to form baryon operators with fixed orbital angular momentum. However, the symmetries of the lattice can be used to form operators which couple to an allowed set of orbital angular momenta. Large sets of operators in each symmetry channel are formed. A variational analysis of correlation matrices for each channel is carried out. The variational analysis allows for the ground state mass and higher excited state masses to be extracted from the correlation matrices. This amounts to pinning down states with hitherto ambiguous orbital angular momenta. A new method known as
Start Date:

07/2010
Duration:

6.00months ## More like this

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