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arXiv · hep-th/0312037

Massive Nonlinear Sigma Models and BPS Domain Walls in Harmonic Superspace

Masato Arai·Evgeny Ivanov·Jiri Niederle
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Abstract

Four-dimensional massive N=2 nonlinear sigma models and BPS wall solutions are studied in the off-shell harmonic superspace approach in which N=2 supersymmetry is manifest. The general nonlinear sigma model can be described by an analytic harmonic potential which is the hyper-Kahler analog of the Kahler potential in N=1 theory. We examine the massive nonlinear sigma model with multi-center four-dimensional target hyper-Kahler metrics and derive the corresponding BPS equation. We study in some detail two particular cases with the Taub-NUT and double Taub-NUT metrics. The latter embodies, as its two separate limits, both Taub-NUT and Eguchi-Hanson metrics. We find that domain wall solutions exist only in the double Taub-NUT case including its Eguchi-Hanson limit.

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Masato Arai, Evgeny Ivanov, Jiri Niederle. 2004-01-16. Massive Nonlinear Sigma Models and BPS Domain Walls in Harmonic Superspace. https://doi.org/10.1016/j.nuclphysb.2003.12.035

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