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arXiv · 1011.1063

Calculation of $\rho$ meson decay width from the PACS-CS configurations

CS collaboration·S. Aoki·K. I. ~Ishikawa·N. Ishizuka·K. Kanaya·Y. Kuramashi·Y. Namekawa·M. Okawa·Y. Taniguchi·A. Ukawa·N. Ukita·T. Yamazaki·T. Yoshié
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Abstract

We present preliminary results on the $\rho$ meson decay width from $N_f=2+1$ full QCD configurations generated by PACS-CS Collaboration. The decay width is estimated from the $P$-wave scattering phase shift for the isospin $I=1$ two-pion system. The finite size formula presented by L\"uscher in the center of mass frame and its extension to non-zero total momentum frame by Rummukainen and Gottlieb are employed for the calculations of the phase shift. Our calculations are carried out at $m_\pi=410\ {\rm MeV}$ ($m_\pi/m_\rho=0.46$) and $a=0.091\ {\rm fm}$ on a $32^3\times 64$ ($La=2.9 {\rm fm}$) lattice.

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CS collaboration, S. Aoki, K. I. ~Ishikawa, N. Ishizuka, K. Kanaya, Y. Kuramashi, Y. Namekawa, M. Okawa, Y. Taniguchi, A. Ukawa, N. Ukita, T. Yamazaki, T. Yoshié. 2010-11-04. Calculation of $\rho$ meson decay width from the PACS-CS configurations. https://arxiv.org/abs/1011.1063

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