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Trace anomaly and dynamical quark mass

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 نشر من قبل Yibo Yang
 تاريخ النشر 2020
  مجال البحث
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We investigated the origin of the RI/MOM quark mass under the Landau gauge at the non-perturbative scale, using the chiral fermion with different quark masses and lattice spacings. Our result confirms that such a mass is non-vanishing based on the linear extrapolation to the chiral and continuum limit, and shows that such a mass comes from the spontaneous chiral symmetry breaking induced by the near zero modes with the eigenvalue $lambda<{cal O}(5m_q)$, and is proportional to the quark matrix element of the trace anomaly at least down to $sim $1.3 GeV.

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