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arXiv · 1511.01849

Search for the H-Dibaryon in two flavor Lattice QCD

Parikshit Junnarkar·Anthony Francis·Jeremy Green·Chuan Miao·Thomas Rae·Hartmut Wittig
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Abstract

We present preliminary results from a lattice QCD calculation of the H-dibaryon using two flavors of $\mathcal{O}(a)$ improved Wilson fermions. We employ local six-quark interpolating operators at the source with a combination of local six-quark and two-baryon operators at the sink with the appropriate quantum numbers of the H-dibaryon and its coupling to the two-baryon channels. We find that the two-baryon operators provide an improved overlap onto the ground state in comparison to the local six-quark operators. We also apply Lüscher's finite volume formalism to obtain information on the nature of the infinite-volume interaction of two particles. Further, the momentum projection to three moving frames enables the isolation of the pole in the infinite-volume scattering amplitude. Preliminary results at pion masses of 450 MeV and 1 GeV clearly indicate the presence of states below the $ΛΛ$ threshold while a finite-volume analysis fails to conclusively show the existence of an infinite-volume bound state.

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Parikshit Junnarkar, Anthony Francis, Jeremy Green, Chuan Miao, Thomas Rae, Hartmut Wittig. 2015-11-05. Search for the H-Dibaryon in two flavor Lattice QCD. https://arxiv.org/abs/1511.01849

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