TY  - CONF
AU  - Bali, Gunnar S.
AU  - Collins, Sara
TI  - Flavour Structure of the Baryon Octet
VL  - 50
CY  - Jülich
PB  - Forschungszentrum Jülich GmbH Zentralbibliothek, Verlag
M1  - FZJ-2020-01422
T2  - Publication Series of the John von Neumann Institute for Computing (NIC) NIC Series
SP  - 175 - 184
PY  - 2020
AB  - We investigate aspects of the structure of different baryons via simulations of quantum chromodynamics in lattice regularisation (Lattice QCD). In particular, we study the mass spectrum, (generalised) isovector charges as well as moments of light cone distribution amplitudes. The charges correspond to moments of parton distribution functions (PDFs). Almost all visible matter in the universe consists of nucleons (i. e. protons and neutrons), which are also the prime probes for new physics, be it in accelerator experiments or dark matter and neutrino detectors. The results will increase the precision of the relation between experimental cross sections and decay rates and the underlying fundamental theory, which describes interactions on the quarks and gluon level rather than interactions with the nucleons (which are composed of quarks and gluons). By extending the study to so-called hyperons that contain strange quarks, in addition to the up and down quarks of the nucleon, at many different quark mass combinations, the validity range of chiral perturbation theory (ChPT) and quark flavour symmetry relations can be checked and low energy constants predicted. The simulations are carried out in N$_f$ = 2 + 1 QCD, neglecting the mass difference between up and down quarks and the electric charges of the quarks. We employ Coordinated Lattice Simulations (CLS) gauge ensembles. These were generated in a Markov chain using the hybrid Monte Carlo (HMC) algorithm with open boundary conditions in time, on several European supercomputers including JUWELS and JUQUEEN. The Wilson fermion discretisation is used, with non-perturbative removal of lattice spacing effects that are proportional to the lattice constant (order $a$ improvement). The main computational task in the analysis that is carried out on the Xeon-Phi Booster module of JURECA of these gauge ensembles with volumes ranging from 64 $\cdot$ 32$^3$ up to 192 $\cdot$ 96$^3$ points, encompassing 1000–2000 configurations each, is the multiple solution of sparse large linear systems with a dimension of up to (2 $\cdot$ 10$^9$)2 complex variables. This is achieved by an adaptive algebraic multigrid algorithm. A novel stochastic method allows us to obtain results for four different baryons and many momentum combinations with little computational overhead, relative to just computing the structure of the nucleon at a few momenta.
T2  - NIC Symposium 2020
CY  - 27 Feb 2020 - 28 Feb 2020, Jülich (Germany)
Y2  - 27 Feb 2020 - 28 Feb 2020
M2  - Jülich, Germany
LB  - PUB:(DE-HGF)8 ; PUB:(DE-HGF)7
UR  - https://juser.fz-juelich.de/record/874412
ER  -