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arXiv · 2602.07232

The Prym-canonical Clifford index

Margherita Lelli-Chiesa·Martina Miseri
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Abstract

We introduce two new invariants of Prym curves, the Prym-canonical Clifford index and the Prym-canonical Clifford dimension. The former is a nonnegative integer (according to Prym-Clifford's theorem), while the latter is a pair of nonnegative ordered integers. We classify Prym curves with Prym-canonical Clifford index equal to 0,1,2. By specialization to hyperelliptic curves, we compute the Prym-canonical Clifford index of a general Prym curve and show that its Prym-canonical Clifford dimension is (0,0).

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Margherita Lelli-Chiesa, Martina Miseri. 2026-02-06. The Prym-canonical Clifford index. https://arxiv.org/abs/2602.07232

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