On some boundary divisors in the moduli spaces of stable Horikawa surfaces with $K^2=2p_g-3$

Ciro Ciliberto, Rita Pardini

We describe the normal stable surfaces with K^2=2p_g-3 and p_g>14 whose only non canonical singularity is a cyclic quotient singularity of type 1/4k(1,2k-1) and the corresponding l…