On curve sections of rank two reflexive sheaves

Citation
S. Nollet et al., On curve sections of rank two reflexive sheaves, COMM ALGEB, 28(12), 2000, pp. 5531-5540
Citations number
10
Categorie Soggetti
Mathematics
Journal title
COMMUNICATIONS IN ALGEBRA
ISSN journal
00927872 → ACNP
Volume
28
Issue
12
Year of publication
2000
Pages
5531 - 5540
Database
ISI
SICI code
0092-7872(2000)28:12<5531:OCSORT>2.0.ZU;2-2
Abstract
Let F be a normalized rank 2 reflexive sheaf on P-3 with Chern classes cl,c z, cs. Let a be the least integer such that 0 not equal (HF)-F-0(alpha) and beta be the smallest integer such that (HF)-F-0(n) has sections whose zero scheme is a curve for all n greater than or equal to beta. We show that if To is the largest root of the cubic polynomial P(T) = T-3 - (6c(2) + 6 alphac(1) + 6 alpha (2) + 1)T + 3(2 alpha + c(1))(c (2) + c(1)alpha + alpha (2)) then beta less than or equal to T-0 - alpha - c(1) - 1. There are applicati ons to the smallest degree of a. surface containing a curves which are the zero schemes of sections of (HF)-F-0(alpha).