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arXiv · hep-th/9608135

Phase Transitions in Softly Broken N=2 SQCD at Non-zero Theta Angle

N. Evans·S. D. H. Hsu·M. Schwetz
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Abstract

We investigate the behavior of softly broken $N=2$ SQCD at non-zero bare theta angle $θ_0$, using superfield spurions to implement the SUSY breaking. We find a first-order phase transition as $θ_0$ is varied from zero to $2 π$, in agreement with a prediction of `t Hooft. The low-energy theta angle $θ_{eff}$, which determines the effective charges of dyonic excitations, has a complicated dependence on $θ_0$ and breaking parameters.

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N. Evans, S. D. H. Hsu, M. Schwetz. 1996-08-20. Phase Transitions in Softly Broken N=2 SQCD at Non-zero Theta Angle. https://doi.org/10.1016/s0550-3213(96)00595-0

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