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Gauge-invariant Renormalization of the Gluino-Glue operator

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 نشر من قبل Marios Costa
 تاريخ النشر 2021
  مجال البحث
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We study the Gluino-Glue operator in the context of Supersymmetric ${cal N}{=}1$ Yang-Mills (SYM) theory. This composite operator is gauge invariant, and it is directly connected to light bound states of the theory; its renormalization is very important as a necessary step for the study of low-lying bound states via numerical simulations. We make use of a Gauge-Invariant Renormalization Scheme (GIRS). This requires the calculation of the Greens function of a product of two Gluino-Glue operators, situated at distinct space-time points. Within this scheme, the mixing with non-gauge invariant operators which have the same quantum numbers is inconsequential. We compute the one-loop conversion factor relating the GIRS scheme to $overline{rm MS}$. This conversion factor can be used in order to convert to $overline{rm MS}$ Greens functions which are obtained via lattice simulations and are renormalized nonperturbatively in GIRS.

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