Maximum entropy analysis of hadron spectral functions and excited states in quenched lattice QCD

PACS Collaboration; S. Aoki; R. Burkhalter; M. Fukugita; S. Hashimoto; N. Ishizuka; Y. Iwasaki; K. Kanaya; T. Kaneko; Y. Kuramashi; M. Okawa; Y. Taniguchi; A. Ukawa; T. Yamazaki; T. Yoshié

arXiv · hep-lat/0110127

Maximum entropy analysis of hadron spectral functions and excited states in quenched lattice QCD

PACS Collaboration·S. Aoki·R. Burkhalter·M. Fukugita·S. Hashimoto·N. Ishizuka·Y. Iwasaki·K. Kanaya·T. Kaneko·Y. Kuramashi·M. Okawa·Y. Taniguchi·A. Ukawa·T. Yamazaki·T. Yoshié

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Abstract

Employing the maximum entropy method we extract the spectral functions from meson correlators at four lattice spacings in quenched QCD with the Wilson quark action. We confirm that the masses and decay constants, obtained from the position and the area of peaks, agree well with the results from the conventional exponential fit. For the first excited state, we obtain $m_{π_1} = 660(590)$ MeV, $m_{ρ_1} = 1540(570)$ MeV, and $f_{ρ_1} = 0.085(36)$ in the continuum limit.

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PACS Collaboration, S. Aoki, R. Burkhalter, M. Fukugita, S. Hashimoto, N. Ishizuka, Y. Iwasaki, K. Kanaya, T. Kaneko, Y. Kuramashi, M. Okawa, Y. Taniguchi, A. Ukawa, T. Yamazaki, T. Yoshié. 2001-10-16. Maximum entropy analysis of hadron spectral functions and excited states in quenched lattice QCD. https://arxiv.org/abs/hep-lat/0110127

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