Interpretation of the Determinant Formulae for the Chiral   Representations of the N=2 Superconformal Algebra
  We show that the N=2 determinant formulae of the Aperiodic NS algebra and the Periodic R algebra can be applied directly to incomplete Verma modules built on chiral primary states and on Ramond ground states, respectively, provided one modifies the interpretation of the zeroes in an appropriate way. That is, the zeroes of the determinat formulae account for the highest weight singular states built on chiral primaries and on Ramond ground states, but the identification of the levels and relative U(1) charges of the singular states is different than for complete Verma modules. In particular, half of the zeroes of the quadratic vanishing surfaces $f^A_{r,s}=0$ and $f^P_{r,s}=0$ correspond to uncharged singular states, and the other half correspond to charged singular states. We derive the spectrum of singular states built on chiral primaries, including the singular states of the Twisted Topological algebra, and the spectrum of singular states built on the Ramond ground states. We also uncover the existence of non-highest weight singular states which are not secondary of any highest weight singular state. 
Beatriz Gato-Rivera and Jose Ignacio Rosado