Abstract
It is a well-known result that a stable curve of compact type over \({\mathbb {C}}\) having two components is hyperelliptic if and only if both components are hyperelliptic and the point of intersection is a Weierstrass point for each of them. With the use of admissible covers, we generalize this characterization in two ways: for stable curves of higher gonality having two smooth components and one node; and for hyperelliptic and trigonal stable curves having two smooth non-rational components and any number of nodes.
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Coelho, J., Sercio, F. Characterizing gonality for two-component stable curves. Geom Dedicata 214, 157–176 (2021). https://doi.org/10.1007/s10711-021-00609-y
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DOI: https://doi.org/10.1007/s10711-021-00609-y