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arXiv · hep-lat/0210012

Lattice study of "f$_{0}$(600) or $σ$"

Teiji Kunihiro·Shin Muroya·Atsushi Nakamura·Chiho Nonaka·Motoo Sekiguchi·Hiroaki Wada
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Abstract

We investigate the propagator of "f$_{0}$(600) or the $σ$" by the full-QCD simulation with Wilson fermions. We calculate the mesonic correlator in the I=0, $J^P=0^{+}$ channel on the $8^{3} \times 16$ lattice. Plaquet action and Wilson fermion action are adopted. A coupling constant $β$ is set to 4.8 and three kinds of hopping parameter, $κ$=0.1846, 0.1874 and 0.1891 are assayed. The disconnected diagram in the propagator is evaluated through taking average over 500 or 1000 Z2 noise. Simulations with the larger hopping parameter provide us with less noisy results. Though the statistics is not yet enough, our results indicate the existence of a pole with a mass in almost the same order as that of the $ρ$.

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Teiji Kunihiro, Shin Muroya, Atsushi Nakamura, Chiho Nonaka, Motoo Sekiguchi, Hiroaki Wada. 2002-10-21. Lattice study of "f$_{0}$(600) or $σ$". https://doi.org/10.1016/s0920-5632(03)01530-5

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