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arXiv · 1503.04708

On Welschinger invariants of descendant type

Eugenii Shustin
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Abstract

We introduce enumerative invariants of real del Pezzo surfaces that count real rational curves belonging to a given divisor class, passing through a generic conjugation-invariant configuration of points and satisfying preassigned tangency conditions to given smooth arcs centered at the fixed points. The counted curves are equipped with Welschinger-type signs. We prove that such a count does not depend neither on the choice of the point-arc configuration, nor on the variation of the ambient real surface. These invariants can be regarded as a real counterpart of (complex) descendant invariants.

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Eugenii Shustin. 2015-03-16. On Welschinger invariants of descendant type. https://arxiv.org/abs/1503.04708

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