Deformation of Schild String

Abstract

We attempt to construct new superstring actions with a $D$-plet of Majorana fermions $ψ^{\cal B}_A$, where ${\cal B}$ is the $D$ dimensional space-time index and $A$ is the two dimensional spinor index, by deforming the Schild action. As a result, we propose three kinds of actions: the first is invariant under N=1 (the world-sheet) supersymmetry transformation and the area-preserving diffeomorphism. The second contains the Yukawa type interaction. The last possesses some non-locality because of bilinear terms of $ψ^{\cal B}_A$. The reasons why completing a Schild type superstring action with $ψ^{\cal B}_A$ is difficult are finally discussed.

12 pages, Latex, both title and abstract are changed, discussion of some relations among our results, Nambu-Goto string and super Yang-Mills theories, added. Results unchanged