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arXiv · 1109.6716

Isolating the Λ(1405) in Lattice QCD

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

The negative-parity ground state of the Λ baryon lies surprisingly low in mass. At 1405.1 MeV, it lies lower than the negative-parity ground state nucleon, even though it has a valence strange quark. Using the PACS-CS (2+1)-flavour full-QCD ensembles available through the ILDG, we employ a variational analysis using 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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Benjamin J. Menadue, Waseem Kamleh, Derek B. Leinweber, M. Selim Mahbub. 2011-09-30. Isolating the Λ(1405) in Lattice QCD. https://doi.org/10.1103/physrevlett.108.112001

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