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arXiv · 1308.1748

Updated Analysis of the Mass of the H Dibaryon from Lattice QCD

P. E. Shanahan·A. W. Thomas·R. D. Young
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Abstract

Recent lattice QCD calculations from the HAL and NPLQCD Collaborations have reported evidence for the existence of a bound state with strangeness -2 and baryon number 2 at quark masses somewhat higher than the physical values. A controlled chiral extrapolation of these lattice results to the physical point suggested that the state, identified with the famed H dibaryon, is most likely slightly unbound (by 13 $\pm$ 14 MeV) with respect to the $\Lambda--\Lambda$ threshold. We report the results of an updated analysis which finds the H unbound by 26 $\pm$ 11 MeV. Apart from the insight it would give us into how QCD is realized in Nature, the H is of great interest because of its potential implications for the equation of state of dense matter and studies of neutron stars. It may also explain the enhancement above the $\Lambda--\Lambda$ threshold already reported experimentally. It is clearly of great importance that the latter be pursued in experiments at the new J-PARC facility.

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P. E. Shanahan, A. W. Thomas, R. D. Young. 2013-08-08. Updated Analysis of the Mass of the H Dibaryon from Lattice QCD. https://arxiv.org/abs/1308.1748

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