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arXiv · 1311.3933

Two-Baryon Correlation Functions in 2-flavour QCD

Anthony Francis·Chuan Miao·Thomas D. Rae·Hartmut Wittig
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Abstract

We present first results for two-baryon correlation functions, computed using $N_f=2$ flavours of O($a$) improved Wilson quarks, with the aim of explaining potential dibaryon bound states, specifically the H-dibaryon. In particular, we use a GEVP to isolate the groundstate using two-baryon (hyperon-hyperon) correlation functions $\big(\langle C_{XY}(t)C_{XY}(0) \rangle$, where $XY=\Lambda\Lambda, \Sigma\Sigma, N\Xi, \cdots\big)$, each of which has an overlap with the H-dibaryon. We employ a `blocking' algorithm to handle the large number of contractions, which may easily be extended to N-baryon correlation functions. We also comment on its application to the analysis of single baryon masses ($n$, $\Lambda$, $\Xi$, $\cdots$). This study is performed on an isotropic lattice with $m_\pi = 460$ MeV, $m_\pi L = 4.7$ and $a = 0.063$ fm.

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Anthony Francis, Chuan Miao, Thomas D. Rae, Hartmut Wittig. 2013-11-15. Two-Baryon Correlation Functions in 2-flavour QCD. https://arxiv.org/abs/1311.3933

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