Compensator Superfield Research Articles

Superspace first order formalism, trivial symmetries and electromagnetic interactions of linearized supergravity

We introduce a first order description of linearized non-minimal (n = −1) supergravity in superspace, using the unconstrained prepotential superfield instead of the conventionally constrained super one forms. In this description, after integrating out the connection-like auxiliary superfield of first-order formalism, the superspace action is expressed in terms of a single superfield which combines the prepotential and compensator superfields. We use this description to construct the supersymmetric cubic interaction vertex 3/2 − 3/2 − 1/2 which describes the electromagnetic interaction between two non-minimal supergravity multiplets (superspin Y = 3/2 which contains a spin 2 and a spin 3/2 particles) and a vector multiplet (superspin Y = 1/2 contains a spin 1 and a spin 1/2 particles). Exploring the trivial symmetries emerging between the two Y = 3/2 supermultiplets, we show that this cubic vertex must depend on the vector multiplet superfield strength. This result generalize previous results for non-supersymmetric electromagnetic interactions of spin 2 particles. The constructed cubic interaction generates non-trivial deformations of the gauge transformations.

Squashed Toric Sigma Models and Mock Modular Forms

We study a class of two-dimensional {mathcal{N}=(2,2)} sigma models called squashed toric sigma models, using their Gauged Linear Sigma Models (GLSM) description. These models are obtained by gauging the global {U(1)} symmetries of toric GLSMs and introducing a set of corresponding compensator superfields. The geometry of the resulting vacuum manifold is a deformation of the corresponding toric manifold in which the torus fibration maintains a constant size in the interior of the manifold, thus producing a neck-like region. We compute the elliptic genus of these models, using localization, in the case when the unsquashed vacuum manifolds obey the Calabi–Yau condition. The elliptic genera have a non-holomorphic dependence on the modular parameter {tau} coming from the continuum produced by the neck. In the simplest case corresponding to squashed {mathbb{C} / mathbb{Z}_{2}} the elliptic genus is a mixed mock Jacobi form which coincides with the elliptic genus of the {mathcal{N}=(2,2)}{SL(2,mathbb{R}) / U(1)} cigar coset.

On the Starobinsky model of inflation from supergravity

We discuss how the higher-derivative Starobinsky model of inflation originates from N=1 supergravity. It is known that, in the old-minimal supergravity description written by employing a chiral compensator in the superconformal framework, the Starobinsky model is equivalent to a no-scale model with F-term potential. We show that the Starobinsky model can also be originated within the so-called new-minimal supergravity, where a linear compensator superfield is employed. In this formulation, the Starobinsky model is equivalent to standard supergravity coupled to a massive vector multiplet whose lowest scalar component plays the role of the inflaton and the vacuum energy is provided by a D-term potential. We also point out that higher-order corrections to the supergravity Lagrangian represent a threat to the Starobinsky model as they can destroy the flatness of the inflaton potential in its scalar field equivalent description.

Anomaly mediation from the Randall-Sundrum to the Dine-Seiberg formalism

In this paper we reconsider the derivation of anomaly mediated supersymmetry breaking. We work in a general formalism where the $F$ term of the conformal compensator superfield is arbitrary. This allows for a continuous interpolation between the original derivation and a more recent Dine-Seiberg derivation of anomaly mediation. We show that the physical soft parameters are independent of the compensator $F$ term and results of two formalisms agree. Finally, we discuss the role of supersymmetric and nonsupersymmetric thresholds in the effective low-energy Lagrangian as well as the effects of explicit small mass parameters (such as $\ensuremath{\mu}$ term) on the superpartner spectrum.

Cosmological supergravity from a massive superparticle and super-cosmological black holes

We describe in superspace a classical theory of two-dimensional (1, 1) dilaton supergravity with a cosmological constant, both with and without coupling to a massive superparticle. We give general exact non-trivial superspace solutions for the compensator superfield that describes the supergravity in both cases. We then use these compensator solutions to construct models of two-dimensional supersymmetric cosmological black holes.

Super black hole from cosmological supergravity with a massive superparticle

We describe in superspace a classical theory of two dimensional (1,1) cosmological dilaton supergravity coupled to a massive superparticle. We give an exact non-trivial superspace solution for the compensator superfield that describes the supergravity, and then use this solution to construct a model of a two-dimensional supersymmetric black hole.

Conformal compensators and manifest type IIB S-duality

Using the conformal compensator superfields of N=2 D=4 supergravity, the Type IIB S-duality transformations are expressed as a linear rotation which mixes the compensator and matter superfields. The classical superspace action for D=4 compactifications of Type IIB supergravity is manifestly invariant under this transformation. Furthermore, the introduction of conformal compensators allows a Fradkin-Tseytlin term to be added to the manifestly SL(2,Z)-covariant sigma model action of Townsend and Cederwall.

Supergravity from a massive superparticle and the simplest super black hole

We describe in superspace a theory of a massive superparticle coupled to a version of two-dimensional (1,1) dilaton supergravity. The (1 + 1)-dimensional supergravity is generated by the stress-energy of the superparticle, and the evolution of the superparticle is reciprocally influenced by the supergravity. We obtain exact superspace solutions for both the superparticle worldline and the supergravity fields. We use the resultant non-trivial compensator superfield solution to construct a model of a two-dimensional supersymmetric black hole.

Gaugino condensation in the early universe

We examine the process of formation of the gaugino condensation within a Nambu-Jona-Lasinio type approach. We construct an effective Lagrangian description for the gaugino condensation which include a Weyl compensator superfield whose vacuum expectation value is related to the gaugino condensation.

New supergravities with central charges and Killing spinors in 2+1 dimensions

We construct a new class of ( p, q)-extended Poincaré supergravity theories in 2+1 dimensions as Chern-Simons theories of supersymmetry algebras with both central and automorphism charges. The new theories have the advantage that they are limits of corresponding ( p, q) adS supergravity theories and, for not too large a value of N = p + q, that they have a natural formulation in terms of off-shell superfields, in which context the distinction between theories having the same value of N but different ( p, q) arises because of inequivalent conformal compensator superfields. We also show that, unlike previously constructed N-extended Poincaré supergravity theories, the new (2,0) theory admits conical spacetimes with Killing spinors. Many of our results on (2,0) Poincaré supergravity continue to apply in the presence of coupling to N = 2 supersymmetric sigma-model matter.

RenormalizableN = 2 Supersymmetric Gauge Theories

Renormalizable supersymmetric models of matter multiplets coupled to a Yang Mills multiplet are studied in the conventional N = 2 superspace. It is found that a consistent formulation of the Feynman rules in superspace requires the introduction of a compensator superfield in the matter sector. If the quantization is performed within the background superfield approach, the use of the compensator is confined to the quantum corrections. The ensuing ghost structure is analyzed and the non-renormalization beyond one-loop is demonstrated. We report an N = 2 superfield calculation of the one-loop β-function via the supercurrent anomaly and thereby derive as a byproduct the finiteness criterion for N = 2 non-Abelian gauge theories.

Quantization of the N = 2 relaxed hypermultiplet

A real compensator superfield of dimension −3 is required for the superspace quantization of the N = 2 relaxed hypermultiplet coupled to a Yang-Mills multiplet. Together with the pregauge conditions of the unconstrained N = 2 matter superfields it allows a complete determinations of the effective action of the matter multiplet. The procedure is checked on the two-point functions of the constrained superfields for the free theory.

Superconformal anomalies from the path-integral measure.

The one-loop superconformal anomalies for a chiral superfield in background N=1 super Yang-Mills and N=1, n=-(1/3) supergravity fields are derived by considering the dependence of the chiral measure on the supergravity compensator superfield. The superspace \ensuremath{\zeta}-function method is used for regularization.