Abstract
We prove some structure results on Weierstrass points on a non-hyperelliptic curve, which are total or almost total ramification points for the gonal covering. It turns out that the corresponding Weierstrass semigroup is strictly related to the splitting type of the gonal scroll containing the canonical model of the curve. We also give a description of the Weierstrass gap sequence in the case of a non ramification point for the gonal cover.
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References
Beauville, A.: Jacobiennes des courbes spectrales et systèmes hamiltoniens complètement intégrables. Acta Math. 164(1), 211–235 (1990)
Brundu, M., Sacchiero, G.: On the varieties parametrizing trigonal curves with assigned Weierstrass points. Commun. Algebra 26(10), 3291–3312 (1998)
Brundu, M., Sacchiero, G.: Stratification of the moduli space of fourgonal curves. Proc. Edinb. Math. Soc. 57(03), 631–686 (2014)
Carvalho, C.: Weierstrass gaps and curves on a scroll. Beitr. Algebra Geom. 43(1), 209–216 (2002)
Carvalho, C., Torres, F.: On numerical semigroups related to covering of curves. Semigroup Forum 67(3), 344–354 (2003)
Casnati, G., Ekedahl, T.: Covers of algebraic varieties. I. A general structure theorem, covers of degree 3,4 and Enriques surfaces. J. Algebraic Geom. 5(3), 439–460 (1996)
Chaves, G.: Revetements ramifies de la droite projective complexe. Math. Z. 226(1), 67–84 (1997)
Coppens, M.: The Weierstrass gap sequences of the total ramification points of trigonal coverings of \(\mathbb{P}^1\). Indag. Math. 47, 245–276 (1985)
Coppens, M.: The Weierstrass gap sequence of the ordinary ramification points of trigonal coverings of \(P^1\); existence of a kind of Weierstrass gap sequence. J. Pure Appl. Algebra 43(1), 11–25 (1986)
Eisenbud, D., Harris, J.: Limit linear series: basic theory. Invent. Math. 85, 337–371 (1986)
Eisenbud, D., Harris, J.: Existence, decomposition and limits of certain Weierstrass points. Invent. Math. 87, 495–515 (1987)
Farkas, G.: Brill–Noether with ramification at unassigned points. J. Pure Appl. Algebra 217(10), 1838–1843 (2013)
Harris, J.: Curves in Projective Space. Presses de L’Université de Montréal, Séminaire de mathématiques supérieures 85 (1982)
Hartshorne, R.: Algebraic Geometry, Graduate Texts in Mathematics, vol. 52. Springer, New York (1977)
Keem, C., Martens, G.: On curves with all Weierstrass points of maximal weight. Arch. Math. 94, 339–349 (2010)
Kim, S.J.: On the existence of Weierstrass gap sequences on trigonal curves. J. Pure Appl. Algebra 63, 171–180 (1990)
Komeda, J.: On the existence of Weierstrass points with a certain semigroup generated by 4 elements. Tsukuba J. Math. 6, 237–270 (1982)
Komeda, J.: On Weierstrass points whose first non-gaps are four. J. Reine Angew. Math. 341, 68–86 (1983)
Komeda, J.: On the existence of Weierstrass points whose first non-gaps are five. Manuscr. Math. 76, 193–211 (1992)
Oliveira, G., Torres, F., Villanueva, J.: On the weight of numerical semigroups. J. Pure Appl. Algebra 214(11), 1955–1961 (2010)
Schreyer, F.O.: Syzygies of canonical curves and special linear series. Math. Ann. 275(1), 105–137 (1986)
Torres, F.: Weierstrass points and double coverings of curves. With application: symmetric numerical semigroups which cannot be realized as Weierstrass semigroups. Manuscr. Math. 83(1), 39–58 (1994)
Acknowledgments
The authors are grateful for the referees’ comments, which were very useful in clarifying the paper. The first author is supported by MIUR funds, PRIN Project Geometria delle varietà algebriche (2010), coordinator A. Verra, and by funds of the Università degli Studi di Trieste-Finanziamento di Ateneo per progetti di ricerca scientifica-FRA 2013. The first author is also supported by GNSAGA of INdAM.
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Communicated by Fernando Torres.
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Beorchia, V., Sacchiero, G. Weierstrass jump sequences and gonality. Semigroup Forum 92, 598–632 (2016). https://doi.org/10.1007/s00233-015-9694-4
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DOI: https://doi.org/10.1007/s00233-015-9694-4