Equivalence classes of subquotients of supersymmetric pseudodifferential operator modules

We study the equivalence classes of the non-resonant subquotients of spaces of pseudodifferential operators between tensor density modules over the 1|1 superline, as modules of the Lie superalgebra of contact vector fields. There is a 2-parameter family of subquotients with any given Jordan-Holder composition series. We give a complete set of even equivalence invariants for subquotients of all lengths. In the critical case of length 6, the even equivalence classes within each non-resonant 2-parameter family are specified by a pencil of conics. In lengths exceeding 6 our invariants are not fully simplified: in length 7 we expect that there are only finitely many equivalences other than conjugation, and in lengths exceeding 7 we expect that conjugation is the only equivalence. We prove this in lengths exceeding 14. We also analyze certain lacunary subquotients.