Brill–Noether loci in codimension two
2013 ◽
Vol 149
(9)
◽
pp. 1535-1568
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AbstractLet us consider the locus in the moduli space of curves of genus$2k$defined by curves with a pencil of degree$k$. Since the Brill–Noether number is equal to$- 2$, such a locus has codimension two. Using the method of test surfaces, we compute the class of its closure in the moduli space of stable curves.