Linearized Non-Minimal Higher Curvature Supergravity

TL;DR

This paper explores the embedding of the $R + R^2$ model within linearized non-minimal supergravity, revealing new propagating auxiliary fields that form various supermultiplets, including massive and ghostly vector supermultiplets.

Contribution

It provides a detailed analysis of the field spectrum and supermultiplet structure in linearized non-minimal supergravity with higher curvature terms, including the identification of new supermultiplets.

Findings

Auxiliary fields become propagating, adding new degrees of freedom.

The spectrum includes two massive chiral supermultiplets.

A massive, vector supermultiplet and a ghostly vector supermultiplet are present.

Abstract

In the framework of linearized non-minimal supergravity (20/20), we present the embedding of the $R + R^2$ model and we analyze its field spectrum. As usual, the auxiliary fields of the Einstein theory now become propagating, giving rise to additional degrees of freedom, which organize themselves into on-shell irreducible supermultiplets. By performing the analysis both in component and superspace formulations we identify the new supermultiplets. On top of the two massive chiral superfields reminiscent of the old-minimal supergravity embedding, the spectrum contains also a consistent physical, massive, vector supermultiplet and a tachyonic ghost, massive, vector supermultiplet.