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DOE OSTI · 22003989

The {Lambda}(1405) in Full QCD

Menadue, Benjamin J·Kamleh, Waseem·Leinweber, Derek B·Mahbub, M Selim
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Abstract

At 1405.1 MeV, the lowest-lying negative-parity state of the {Lambda} baryon lies surprising low. Indeed, this is lower than the lowest negative-parity state of the nucleon, even though the {Lambda}(1405) possesses a valence strange quark. However, previous Lattice QCD studies have been unable to identify such a low-lying state. Using the PACS-CS (2+1)-flavour full-QCD ensembles, available through the ILDG, we utilise a variational analysis with source and sink smearing to isolate this elusive state. We find three low-lying odd-parity states, and for the first time reproduce the correct level ordering with respect to the nearby scattering thresholds.

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72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDSFLAVOR MODELLAMBDA-1405 BARYONSLATTICE FIELD THEORYMEV RANGENUCLEONSPARITYPERTURBED ANGULAR CORRELATIONQUANTUM CHROMODYNAMICSRESONANCE PARTICLESS QUARKSSCATTERINGVALENCEVARIATIONAL METHODS

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Menadue, Benjamin J, Kamleh, Waseem, Leinweber, Derek B, Mahbub, M Selim. 2011-12-14. The {Lambda}(1405) in Full QCD. https://doi.org/10.1063/1.3667313

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