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Baryon interactions from lattice QCD with physical masses -- Overview and $S = 0, -4$ sectors --

137   0   0.0 ( 0 )
 نشر من قبل Takumi Doi
 تاريخ النشر 2017
  مجال البحث
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Nuclear forces and hyperon forces are studied by lattice QCD. Simulations are performed with (almost) physical quark masses, $m_pi simeq 146$ MeV and $m_K simeq 525$ MeV, where $N_f=2+1$ nonperturbatively ${cal O}(a)$-improved Wilson quark action with stout smearing and Iwasaki gauge action are employed on the lattice of $(96a)^4 simeq (8.1mbox{fm})^4$ with $a^{-1} simeq 2.3$ GeV. In this report, we give the overview of the theoretical framework and present the numerical results for two-nucleon forces ($S=0$) and two-$Xi$ forces ($S=-4$). Central forces are studied in $^1S_0$ channel, and central and tensor forces are obtained in $^3S_1$-$^3D_1$ coupled channel analysis.

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