First results of baryon interactions from lattice QCD with physical masses (1) -- General overview and two-nucleon forces --

Takumi Doi; Sinya Aoki; Shinya Gongyo; Tetsuo Hatsuda; Yoichi Ikeda; Takashi Inoue; Takumi Iritani; Noriyoshi Ishii; Takaya Miyamoto; Keiko Murano; Hidekatsu Nemura; Kenji Sasaki

arXiv · 1512.01610

First results of baryon interactions from lattice QCD with physical masses (1) -- General overview and two-nucleon forces --

Takumi Doi·Sinya Aoki·Shinya Gongyo·Tetsuo Hatsuda·Yoichi Ikeda·Takashi Inoue·Takumi Iritani·Noriyoshi Ishii·Takaya Miyamoto·Keiko Murano·Hidekatsu Nemura·Kenji Sasaki

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Abstract

We present the lattice QCD studies for baryon-baryon interactions for the first time with (almost) physical quark masses. $N_f = 2+1$ gauge configurations are generated with the Iwasaki gauge action and nonperturbatively $O(a)$-improved Wilson quark action with stout smearing on the lattice of $(96 a)^4 \simeq (8.2 {\rm fm})^4$ with $a \simeq 0.085$ fm, where $m_π\simeq 146$ MeV and $m_K \simeq 525$ MeV. Baryon forces are calculated from Nambu-Bethe-Salpeter (NBS) correlation functions using the time-dependent HAL QCD method. In this report, we first give the general overview of the theoretical frameworks essential to the physical point calculation of baryon forces. We then present the numerical results for the two-nucleon central and tensor forces in $^3S_1$-$^3D_1$ coupled channel and the central force in $^1S_0$ channel. In particular, a clear signal is obtained for the tensor force.

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Takumi Doi, Sinya Aoki, Shinya Gongyo, Tetsuo Hatsuda, Yoichi Ikeda, Takashi Inoue, Takumi Iritani, Noriyoshi Ishii, Takaya Miyamoto, Keiko Murano, Hidekatsu Nemura, Kenji Sasaki. 2015-12-05. First results of baryon interactions from lattice QCD with physical masses (1) -- General overview and two-nucleon forces --. https://arxiv.org/abs/1512.01610

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