Higher Spin Supersymmetry at the Cosmological Collider: Sculpting SUSY
  Rilles in the CMB
  We study the imprint of higher spin supermultiplets on cosmological
correlators, namely the non-Gaussianity of the cosmic microwave background.
Supersymmetry is used as a guide to introduce the contribution of fermionic
higher spin particles, which have been neglected thus far in the literature.
This necessarily introduces more than just a single additional fermionic
superpartner, since the spectrum of massive, higher spin supermultiplets
includes two propagating higher spin bosons and two propagating higher spin
fermions, which all contribute to the three point function. As an example we
consider the half-integer superspin $\textsf{Y}=s+1/2$ supermultiplet, which
includes particles of spin values $j=s+1,~j=s+1/2,~j=s+1/2$ and $j=s$. We
compute the curvature perturbation 3-point function for higher spin particle
exchange and find that the known $P_{s}(\cos \theta)$ angular dependence is
accompanied by superpartner contributions that scale as $P_{s+1}(\cos \theta)$
and $\sum_{m}P^{m}_{s} (\cos \theta)$, with $P_{s}$ and $P_{s} ^m$ defined as
the Legendre and Associated Legendre polynomials respectively. We also compute
the tensor-scalar-scalar 3-point function, and find a complicated angular
dependence as an integral over products of Legendre and associated Legendre
polynomials.
