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تسجيل مستخدم جديد$LambdaLambda$ and N$Xi$ interactions from Lattice QCD near the physical point
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The $S$-wave $LambdaLambda$ and $N Xi$ interactions are studied on the basis of the (2+1)-flavor lattice QCD simulations close to the physical point ($m_pi simeq 146{rm{MeV}}$ and $m_K simeq 525{rm{MeV}}$). Lattice QCD potentials in four different spin-isospin channels are extracted by using the coupled-channel HAL QCD method and are parametrized by analytic functions to calculate the scattering phase shifts. The $Lambda Lambda$ interaction at low energies shows only a weak attraction, which does not provide a bound or resonant dihyperon. The $NXi$ interaction in the spin-singlet and isospin-singlet channel is most attractive and lead the $NXi$ system near unitarity. Relevance to the strangeness=$-2$ hypernuclei as well as to two-baryon correlations in proton-proton, proton-nucleus and nucleus-nucleus collisions is also discussed.
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