Fermionic screenings and chiral de Rham complex on CY manifolds with   line bundles
  We represent a generalization of Borisov's construction of chiral de Rham complex for the case of line bundle twisted chiral de Rham complex on Calabi-Yau hypersurface in projective space. We generalize the differential associated to the polytope $\Delta$ of the projective space $\mathbb{P}^{d-1}$ by allowing nonzero modes for the screening currents forming this differential. It is shown that the numbers of screening current modes define the support function of toric divisor of a line bundle on $\mathbb{P}^{d-1}$ that twists the chiral de Rham complex on Calabi-Yau hypersurface. 
Sergei E. Parkhomenko
hep-th