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arXiv · 1106.5180

Threefold extremal contractions of types (IC) and (IIB)

Shigefumi Mori·Yuri Prokhorov
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Abstract

Let $(X,C)$ be a germ of a threefold $X$ with terminal singularities along an irreducible reduced complete curve $C$ with a contraction $f: (X,C)\to (Z,o)$ such that $C=f^{-1}(o)_{red}$ and $-K_X$ is ample. Assume that $(X,C)$ contains a point of type (IC) or (IIB). We complete the classification of such germs in terms of a general member $H\in |\mathcal O_X|$ containing $C$.

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Shigefumi Mori, Yuri Prokhorov. 2011-06-25. Threefold extremal contractions of types (IC) and (IIB). https://doi.org/10.1017/s0013091513000850

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