Particles in the superworldline and BRST

Abstract

In this short note we discuss 𝑁 -supersymmetric worldlines of relativistic massless particles and review the known result that physical spin- 𝑁 / 2 fields are in the first BRST cohomology group. For 𝑁 = 1 , 2 , 4, emphasis is given to particular deformations of the BRST differential, that implement either a covariant derivative for a gauge theory or a metric connection in the target space seen by the particle. In the end, we comment about the possibility of incorporating Ramond-Ramond fluxes in the background.