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Multi-instanton calculus versus exact results in N=2 supersymmetric QCD

Toshiyuki Harano·Masatoshi Sato
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Abstract

Microscopic tests of the exact results are performed in $N=2$ supersymmetric $SU(2)$ QCD. We present the complete construction of the multi-instanton in $N=2$ supersymmetric QCD. All the defining equations of the super instanton are reduced to the algebraic equations. Using this result, we calculate the two-instanton contribution ${\cal F}_2$ to the prepotential ${\cal F}$ for the arbitrary $N_f$ theories. For $N_f=0,1,2$, instanton calculus agrees with the prediction of the exact results, however, for $N_f=3,4$, we find discrepancies between them. We propose improved curves of the exact results for the massive $N_f=3$ and massless $N_f=4$ theories.

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Toshiyuki Harano, Masatoshi Sato. 1996-08-10. Multi-instanton calculus versus exact results in N=2 supersymmetric QCD. https://doi.org/10.1016/s0550-3213(96)00599-8

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