Abstract
We study birational projective models of π2,2 obtained from the moduli space of curves with nonspecial divisors. We describe geometrically which singular curves appear in these models and show that one of them is obtained by blowing down the Weierstrass divisor in the moduli stack of π©-stable curves π2,2(π©) defined by Smyth. As a corollary, we prove projectivity of the coarse moduli space M2,2(π©).
Communicated by: R. Cavalieri
References
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