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تسجيل مستخدم جديد$K_L$ - $K_S$ mass difference computed with a 171 MeV pion mass
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Ziyuan Bai
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In this work, we used a $32^3 times 64 times 32$, 2+1 flavor domain wall lattice with Iwasaki+DSDR gauge action. The pion mass is 171 MeV and the kaon mass is 492 MeV. We implement the Glashow-Iliopoulos-Maiani (GIM) cancellation using charm quark masses of 750 MeV and 592 MeV. This is an intermediate calculation, in that we are using both a coarse lattice spacing (1/a = 1.37GeV) so we expect significant discretization error coming from charm quark mass and we are also using unphysical kinematics for the pion. The main purpose of this calculation is to study the contribution from the two-pion intermediate state when the energy of a two-pion state is lower than that of the kaon, as well as the corresponding finite volume correction to the $Delta M_K$.
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We report on the first complete calculation of the $K_L-K_S$ mass difference, $Delta M_K$, using lattice QCD. The calculation is performed on a 2+1 flavor, domain wall fermion ensemble with a 330MeV pion mass and a 575 MeV kaon mass. We use a quenche
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