Two-loop effective potential for general higher-derivative superfield models

Superfield effective potential

A superfield method of computing the effective potential in supersymmetric field theories is suggested. Analysis of the structure of the effective potential in the Wess-Zumino model is carried out. It is shown that the superfield effective potential is defined by three objects: kahlerian effective potential, chiral effective potential and auxiliary fields' effective potential. One-loop kahlerian effective potential is calculated using the superfield heat kernel technique. A corresponding superfield kernel is found in explicit form. Procedure for computing higher loop corrections is developed. …

One-loop polarization operator of the quantum gauge superfield for ${\cal N}=1$ SYM regularized by higher derivatives

We consider the general ${\cal N}=1$ supersymmetric gauge theory with matter, regularized by higher covariant derivatives without breaking the BRST invariance, in the massless limit. In the $ξ$-gauge we obtain the (unrenormalized) expression for the two-point Green function of the quantum gauge superfield in the one-loop approximation as a sum of integrals over the loop momentum. The result is presented as a sum of three parts: the first one corresponds to the pure supersymmetric Yang--Mills theory in the Feynman gauge, the second one contains all gauge dependent terms, and the third one is th…

Two-loop effective potentials in general N=2, d=3 chiral superfield model

We study local superspace contributions to low-energy effective action in general chiral three-dimensional superfield model. The effective Kahler and chiral potentials are computed in explicit form up to the two-loop order. In accordance with the non-renormalization theorem, the ultraviolet divergences appear only in the full superspace while the effective chiral potential receives only finite quantum contributions in the massless case. As an application, the two-loop effective scalar potential is found for the three-dimensional N=2 supersymmetric Wess-Zumino model.

Superfield formalism for the one loop effective action and CP(N) model in three dimensions

To obtain the one loop effective action for a given superfield theory, one encounters the notion such as the `supertrace' of a differential operator on superspace. We develop, in a systematic way for the superspace of arbitrary dimension, a method to determine the supertrace precisely. We present a formula to express the supertrace explicitly as the superspace integral, which enables us to write the one loop effective action within the superfield formalism and still maintain the manifest supersymmetry. In the second part of the paper, we apply the result to a three dimensional N=1 supersymmetr…

Auxiliary fields rescaling in higher-derivative supergravity

We study higher--derivative supergravity with curvature squared terms in different bases. Performing a Weyl rescaling only on the metric or on all the superfield components does not allow to obtain a normalized kinetic Einstein term from a $\cR+\cR^2$ theory. It is necessary to combine a Legendre transformation and a Weyl rescaling on a $\cR+\cR^2$ theory to arrive at a theory of supergravity coupled to matter. This mechanism is applied to supergravity coupled to a general function $k(R,\BR,Φ,\barΦ)$, where $R$ is one of the supergravity chiral superfields and $Φ$ a chiral matter superfield.

Superfield approach to higher derivative N=1 superconformal mechanics

We formulate the equations which determine a potential function in an $\mathcal{N}=1$ higher derivative supersymmetric mechanics compatible with the $osp(2|1)\oplus so(d)$ symmetry and provide a few explicit examples.

Effective Potential in the 3D Massive 2-form Gauge Superfield Theory

In the $\mathcal{N}=1$, $d=3$ superspace, we propose a massive superfield theory formulated in terms of a spinor gauge superfield, whose component content includes a two-form field, and a real scalar matter superfield. For this model, we explicitly calculate the one-loop correction to the superfield effective potential. In particular, we show that the one-loop effective potential is independent the gauge-fixing parameters.

Effective action in general chiral superfield model

The effective action in general chiral superfield model with arbitrary kählerian potential $K(\barΦ,Φ)$ and chiral (holomorphic) potential $W(Φ)$ is considered. The one-loop and two-loop contributions to kählerian effective potential and two-loop (first non-zero) contribution to chiral effective potential are found for arbitrary form of functions $K(\barΦ,Φ)$ and $W(Φ)$. It is found that despite the theory is non-renormalizable in general case two-loop contribution to holomorphic effective potential is always finite.

Type IIB at eight derivatives: insights from Superstrings, Superfields and Superparticles

We study the non-linear structure of Type IIB eight-derivative couplings involving the metric and the complexified three-form $G_3$. We show that, at the level of five-point string amplitudes, the kinematics in the maximally R-symmetry-violating sector is fully matched by standard superspace integrals and by superparticle amplitudes in M-theory on a two-torus. The latter approach is used to determine the complete effective action in this sector and to verify its invariance under SL$(2,\mathbb{Z})$ duality. We further comment on the general structure of the higher-point kinematics. Compactifica…

Towards the n-point one-loop superstring amplitude I: Pure spinors and superfield kinematics

This is the first installment of a series of three papers in which we describe a method to determine higher-point correlation functions in one-loop open-superstring amplitudes from first principles. In this first part, we exploit the synergy between the cohomological features of pure-spinor superspace and the pure-spinor zero-mode integration rules of the one-loop amplitude prescription. This leads to the study of a rich variety of multiparticle superfields which are local, have covariant BRST variations, and are compatible with the particularities of the pure-spinor amplitude prescription. Se…

On the superfield effective potential in three dimensions

We develop the superfield approach to the effective potential in three dimensions and calculate the one-loop and two-loop kählerian effective potential in commutative and noncommutative cases.

On the finiteness of noncommutative supersymmetric QED$_3$ in the covariant superfield formulation

The three-dimensional noncommutative supersymmetric QED is investigated within the superfield approach. We prove the absence of UV/IR mixing in the theory at any loop order and demonstrate its one-loop finiteness.

On a structure of the one-loop divergences in $4D, {\cal N}=2$ supersymmetric sigma-model

We study the quantum structure of four-dimensional ${\cal N}=2$ superfield sigma-model formulated in harmonic superspace in terms of the omega-hypermultiplet superfield $ω$. The model is described by harmonic superfield sigma-model metric $g_{ab}(ω)$ and two potential-like superfields $L^{++}_{a}(ω)$ and $L^{(+4)}(ω)$. In bosonic component sector this model describes some hyper-Kähler manifold. The manifestly ${\cal N}=2$ supersymmetric covariant background-quantum splitting is constructed and the superfield proper-time technique is developed to calculate the one-loop effective action. The one…

Superfield Effective Action in the Noncommutative Wess-Zumino Model

We introduce the concept of superfield effective action in noncommutative N=1 supersymmetric field theories containing chiral superfields. One and two loops low-energy contributions to the effective action are found for the noncommutative Wess-Zumino model. The one loop Kahlerian effective potential coincides with its commutative counterpart. We show that the two loops nonplanar contributions to the Kahlerian effective potential are leading in the case of small noncommutativity. The structure of the leading chiral corrections to the effective action and the behaviour of the chiral effective po…

On the decoupling of heavy states in higher-derivative supersymmetric field theories

We study the problem of decoupling of heavy chiral superfields in four-dimensional $N=1$ supersymmetric field theories with Lorentz-invariant and Lorentz-violating higher-derivative terms. We demonstrate that the earlier found effect of large logarithmic quantum corrections, due to heavy chiral superfields, takes place not only if the theory possesses quantum divergences, but also for essentially finite theories involving higher derivative terms, both Lorentz-invariant and Lorentz-breaking ones.

One-loop Regularization of Supergravity II: The Dilaton and the Superfield Formulation

The on-shell regularization of the one-loop divergences of supergravity theories is generalized to include a dilaton of the type occurring in effective field theories derived from superstring theory, and the superfield structure of the one-loop corrections is given. Field theory anomalies and quantum contributions to soft supersymmetry breaking are discussed. The latter are sensitive to the precise choice of couplings that generate Pauli-Villars masses, which in turn reflect the details of the underlying theory above the scale of the effective cut-off. With a view to the implementation the Gre…

Pure spinor superfields and Born-Infeld theory

We present a method for introducing and analysing higher-derivative deformations of maximally supersymmetric field theories. Such terms are built in the pure spinor superfield framework, using a set of operators representing physical fields. The action for abelian Born-Infeld theory becomes polynomial in this language, and contains only a four-point interaction in addition to the free action. Simplifications also occur in the non-abelian case.

Functional renormalization group flows of $\mathcal{N}=1$ supersymmetric abelian gauge model with one chiral and one vector superfield

We apply the functional renormalization group approach to a $\mathcal{N}=1$ supersymmetric gauge model with one chiral superfield coupled to a vector $U(1)$ superfield. We find that the nonrenormalization theorem still works at leading order in the supercovariant derivative expansion of the fields. We also find the beta functions and we study the behavior of its fixed points in the local potential approximation. Regulators are also discussed.

The higher derivative regularization and quantum corrections in ${\cal N}=2$ supersymmetric theories

We construct a new version of the higher covariant derivative regularization for a general ${\cal N}=2$ supersymmetric gauge theory formulated in terms of ${\cal N}=1$ superfields. This regularization preserves both supersymmetries of the classical action, namely, the invariance under the manifest ${\cal N}=1$ supersymmetry and under the second hidden on-shell supersymmetry. The regularizing ${\cal N}=2$ supersymmetric higher derivative term is found in the explicit form in terms of ${\cal N}=1$ superfields. Thus, ${\cal N}=2$ supersymmetry is broken only by the gauge fixing procedure. Then we…

On quantum properties of the four-dimensional generic chiral superfield model

We study a problem of systematical evaluation of the quantum corrections for general 4D supersymmetric Kähler sigma models with chiral and antichiral superpotentials. Using manifestly reparametrization covariant techniques (the background-quantum splitting and proper-time representation) in the ${\cal N}=1$ superspace we show how to define unambiguously the one-loop effective action. We introduce the reparametrization covariant derivatives acting on superfields and prove that their algebra is analogous to algebra in super Yang-Mills (SYM) theory. This analogy allows us to use for evaluation of…

New form of the NSVZ relation at the two-loop level

Recently the exact NSVZ $β$-function was rewritten in the form of a relation between the $β$-function and the anomalous dimensions of the quantum gauge superfield, of the Faddeev--Popov ghosts, and of the matter superfields. It was also suggested that this form of the NSVZ equation follows from an underlying equation relating two-point Green functions of the theory. Here we demonstrate that this relation is satisfied at the two-loop level for the non-Abelian ${\cal N}=1$ supersymmetric gauge theories in the case of using the simplest (BRST non-invariant) version of the higher covariant derivat…

N=1 supersymmetric Yang-Mills theory in d=4 and its Batalin-Vilkovisky quantization by spinor superfields

Four dimensional N=1 supersymmetric Yang-Mills theory action is written in terms of the spinor superfields in transverse gauge. This action is seemingly first order in space-time derivatives. Thus, it suggests that the generalized fields approach of obtaining Batalin-Vilkovisky quantization can be applicable. In fact, generalized fields which collect spinor superfields possessing different ghost numbers are introduced to obtain the minimal solution of its Batalin-Vilkovisky master equation in a compact form.

Superfield Effective Potential for the 2-form field

We develop a theory describing the superfield extension of the 2-form field coupled to usual chiral and real scalar superfield and find the one-loop Kählerian effective potential in this theory.

Gauge and matter superfield theories on $S^2$

We develop a superfield formulation of gauge and matter field theories on a two-dimensional sphere with rigid N=(2,2) as well as extended supersymmetry. The construction is based on a supercoset SU(2|1)/[U(1) x U(1)] containing $S^2$ as the bosonic subspace. We derive an explicit form of supervielbein and covariant derivatives on this coset, and use them to construct classical superfield actions for gauge and matter supermultiplets in this superbackground. We then apply superfield methods for computing one-loop partition functions of these theories and demonstrate how the localization techniqu…

Two-loop low-energy effective actions in N=2 and N=4 three-dimensional SQED

We study two-loop Euler-Heisenberg effective actions in three-dimensional N=2 and N=4 supersymmetric quantum electrodynamics (SQED) without Chern-Simons term. We find exact expressions for propagators of chiral superfields interacting with slowly-varying N=2 gauge superfield. Using these propagators we compute two-loop effective actions in the N=2 and N=4 SQED as the functionals of superfield strengths and their covariant spinor derivatives. The obtained effective actions contain new terms having no four-dimensional analogs. As an application, we find two-loop quantum corrections to the moduli…

Superfield Effective Potential for the Supersymmetric Topologically Massive Gauge theory in Four Dimensions

We explicitly calculate the one-loop effective potential for the supersymmetric topologically massive gauge theory in four dimensions, where the chiral scalar superfield is directly coupled to the field strength for the gauge spinor superfield.

The NSVZ $β$-function for theories regularized by higher covariant derivatives: the all-loop sum of matter and ghost singularities

The contributions of the matter superfields and of the Faddeev--Popov ghosts to the $β$-function of ${\cal N}=1$ supersymmetric gauge theories defined in terms of the bare couplings are calculated in all orders in the case of using the higher covariant derivative regularization. For this purpose we use the recently proved statement that the $β$-function in these theories is given by integrals of double total derivatives with respect to the loop momenta. These integrals do not vanish due to singularities of the integrands. This implies that the $β$-function beyond the one-loop approximation is …

One loop divergences and anomalies from chiral superfields in supergravity

We apply the heat kernel method (using Avramidi's non-recursive technique) to the study of the effective action of chiral matter in a complex representation of an arbitrary gauge sector coupled to background U(1) supergravity. This generalizes previous methods, which restricted to 1) real representations of the gauge sector in traditional Poincaré supergravity or 2) vanishing supergravity background. In this new scheme, we identify a classical ambiguity in these theories which mixes the supergravity U(1) with the gauge U(1). At the quantum level, this ambiguity is maintained since the effectiv…

Two-loop renormalization of the matter superfields and finiteness of ${\cal N}=1$ supersymmetric gauge theories regularized by higher derivatives

The two-loop anomalous dimension of the chiral matter superfields is calculated for a general ${\cal N}=1$ supersymmetric gauge theory regularized by higher covariant derivatives. We obtain both the anomalous dimension defined in terms of the bare couplings, and the one defined in terms of the renormalized couplings for an arbitrary renormalization prescription. For the one-loop finite theories we find a simple relation between the higher derivative regulators under which the anomalous dimension defined in terms of the bare couplings vanishes in the considered approximation. In this case the o…

$N=1$ supersymmetry and the three loop anomalous dimension for the chiral superfield

We calculate the three loop anomalous dimension for a general $N=1$ supersymmetric gauge theory. The result is used to probe the possible existence of renormalisation invariant relationships between the Yukawa and gauge couplings.

One-loop effective action in ${\cal N}=2$ supersymmetric massive Yang-Mills theory

We consider the ${\cal N}=2$ supersymmetric theory of the massive Yang-Mills field formulated in the ${\cal N}=2$ harmonic superspace. The various gauge-invariant forms of writing the mass term in the action (in particular, using the Stueckelberg superfield), which result in dual formulations of the theory, are presented. We develop a gauge-invariant and explicitly supersymmetric scheme of the loop off-shell expansion of the superfield effective action. In the framework of this scheme, we calculate gauge-invariant and explicitly ${\cal N}=2$ supersymmetric one-loop counterterms including new c…

Ghostbusters in higher derivative supersymmetric theories: who is afraid of propagating auxiliary fields?

We present for the first time a ghost-free higher-derivative chiral model with a propagating auxiliary F-term field (highest component of the chiral multiplet). We obtain this model by removing a ghost in a higher derivative chiral model, with Higgsing it in terms of an auxiliary vector superfield. Depending on the sign of the quadratic derivative term of the chiral superfield, the model contains two ghost free branches of the parameter regions. We find that supersymmetry is spontaneously broken in one branch while it is preserved in the other branch. As a consequence of dynamical F-term field…

On the higher-derivative supersymmetric gauge theory

We study the one-loop low-energy effective action for the higher-derivative superfield gauge theory coupled to a chiral matter.

Holomorphic effective potential in general chiral superfield model

We study a holomorphic effective potential $W_{eff}(Φ)$ in chiral superfield model defined in terms of arbitrary kählerian potential $K(\barΦ,Φ)$ and arbitrary chiral potential $W(Φ)$. Such a model naturally arises as an ingredient of low-energy limit of superstring theory and it is called here the general chiral superfield model. Generic procedure for calculating the chiral loop corrections to effective action is developed. We find lower two-loop correction in the form $W^{(2)}_{eff}(Φ)= 6/(4π)^4 \bar{W}^{'''2}(0){(\frac{W^{''}(Φ)}{K^2_{Φ\barΦ(0,Φ)}})}^3$ where $K_{Φ\barΦ}(0,Φ)=\frac{\partial…

Ghost-free vector superfield actions in supersymmetric higher-derivative theories

We systematically construct ghost-free higher-derivative actions of Abelian vector supermultiplets in four-dimensional ${\cal N}=1$ global supersymmetric theories. After giving a simple example which illustrates that a naive introduction of a higher-derivative term gives rise to a ghost, we discuss possible building blocks for a ghost-free action and explicitly show that their bosonic parts have no ghost mode and the auxiliary field $\boldsymbol{D}$ does not propagate. Higher-derivative terms yield higher powers of the auxiliary field $\boldsymbol{D}$ in the actions, and the D-term equations o…

N=2 Conformal Supergravity from Twistor-String Theory

A chiral superfield strength in N=2 conformal supergravity at linearized level is obtained by acting two superspace derivatives on N=4 chiral superfield strength which can be described in terms of N=4 twistor superfields. By decomposing SU(4)_R representation of N=4 twistor superfields into the SU(2)_R representation with an invariant U(1)_R charge, the surviving N=2 twistor superfields contain the physical states of N=2 conformal supergravity. These N=2 twistor superfields are functions of homogeneous coordinates of weighted complex projective space WCP^{3|4} where the two weighted fermionic …

Constrained Superfields in Dynamical Background

We study the nonlinear realization of supersymmetry in a dynamical/cosmological background in which derivative terms like kinetic terms are finite. Starting from linearly realized theories, we integrate out heavy modes without neglecting derivative terms to obtain algebraic constraints on superfields. Thanks to the supersymmetry breaking contribution by the kinetic energy, the validity of constrained superfields can be extended to cosmological regimes and phenomena such as reheating after inflation, kinetic-energy domination, and the kinetic and standard misalignment of axion.

Higher-Derivative Chiral Superfield Actions Coupled to N=1 Supergravity

We construct N=1 supergravity extensions of scalar field theories with higher-derivative kinetic terms. Special attention is paid to the auxiliary fields, whose elimination leads not only to corrections to the kinetic terms, but to new expressions for the potential energy as well. For example, a potential energy can be generated even in the absence of a superpotential. Our formalism allows one to write a supergravity extension of any higher-derivative scalar field theory and, therefore, has applications to both particle physics and cosmological model building. As an illustration, we couple the…

On effective Kähler potential in N=2, d=3 SQED

We compute the two-loop effective Kähler potential in three-dimensional N=2 supersymmetric electrodynamics with Chern-Simons kinetic term for the gauge superfield. The effective action is constructed on the base of background field method with one parametric family of gauges. In such an approach, the quadratic part of quantum action mixes the gauge and matter quantum superfields yielding the complications in the computations of the loop supergraphs. To avoid this obstacle and preserve dependence on the gauge parameter we make a nonlocal change of quantum matter superfields after which the prop…

Low-energy next-to-leading contributions to the effective action in ${\cal N}=4$ SYM theory

Using formulation of ${\cal N}=4$ SYM theory in terms of ${\cal N}=1$ superfields superfields we construct the derivative expansion of the one-loop ${\cal N}=4$ SYM effective action in background fields corresponding to constant Abelian strength $F_{mn}$ and constant hypermultiplet. Any term of the effective action derivative expansion can be rewritten in terms of ${\cal N}=2$ superfields. The action is manifestly ${\cal N}=2$ supersymmetric but on-shell hidden ${\cal N}=2$ supersymmetry is violated. We propose a procedure which allows to restore the hidden ${\cal N}=2$ invariance.

Dynamical (super)symmetry vacuum properties of the supersymmetric Chern-Simons-matter model

By computing the two-loop effective potential of the D=3 N=1 supersymmetric Chern-Simons model minimally coupled to a massless self-interacting matter superfield, it is shown that supersymmetry is preserved, while the internal U(1) and the scale symmetries are broken at two-loop order, dynamically generating masses both for the gauge superfield and for the real component of the matter superfield.

关于6维N=(1,1)超对称杨-米尔斯理论中有效作用量的双圈发散

On two-loop divergences of effective action in $6D$, ${\cal N}=(1,1)$ SYM theory

本文在N=(1,0)调和超空间中研究了6维N=(1,1)超对称规范理论的双圈有效作用量离壳发散，利用调和超场背景场方法构造有效作用量，计算了规范场与超多重态混合发散并证明其在调和空间中非局域。

On structure of effective action in four-dimensional quantum dilaton supergravity

A general structure of effective action in new chiral superfield model associated with $N=1$, $D=4$ supergravity is investigated. This model corresponds to finite quantum field theory and does not demand the regularization and renormalization at effective action calculation. It is shown that in local approximation the effective action is defined by two objects called general superfield effective lagrangian and chiral superfield effective lagrangian. A proper-time method is generalized for calculation of these two effective lagrangians in superfield manner. Power expansion of the effective acti…

非局部旋量超场理论

Nonlocal spinor superfield theory

本文提出一种三维非局部旋量超场模型，通过引入形式因子构建局部旋量超场作用，并最小耦合标量超场，计算一阶有效势作为该新理论的初步扰动计算示例。

Higher Spin BRS Cohomology of Supersymmetric Chiral Matter in D=4

We examine the BRS cohomology of chiral matter in $N=1$, $D=4$ supersymmetry to determine a general form of composite superfield operators which can suffer from supersymmetry anomalies. Composite superfield operators $\Y_{(a,b)}$ are products of the elementary chiral superfields $S$ and $\ov S$ and the derivative operators $D_\a$, $\ov D_{\dot \b}$ and $\pa_{\a \dot \b}$. Such superfields $\Y_{(a,b)}$ can be chosen to have `$a$' symmetrized undotted indices $\a_i$ and `$b$' symmetrized dotted indices $\dot \b_j$. The result derived here is that each composite superfield $\Y_{(a,b)}$ is subject…

Effective action of three-dimensional extended supersymmetric matter on gauge superfield background

We study the low-energy effective actions for gauge superfields induced by quantum N=2 and N=4 supersymmetric matter fields in three-dimensional Minkowski space. Analyzing the superconformal invariants in the N=2 superspace we propose a general form of the N=2 gauge invariant and superconformal effective action. The leading terms in this action are fixed by the symmetry up to the coefficients while the higher order terms with respect to the Maxwell field strength are found up to one arbitrary function of quasi-primary N=2 superfields constructed from the superfield strength and its covariant s…

Supergraph calculation of one-loop divergences in higher-derivative $6D$ SYM theory

We apply the harmonic superspace approach for calculating the divergent part of the one-loop effective action of $6D$, ${\cal N}=(1,0)$ supersymmetric higher-derivative gauge theory with a dimensionless coupling constant. Our consideration uses the background superfield method allowing to carry out the analysis of the effective action in a manifestly gauge covariant and ${\cal N}=(1,0)$ supersymmetric way. We exploit the regularization by dimensional reduction in which the divergences are absorbed into a renormalization of the coupling constant. Having the expression for the one-loop divergenc…

Gauge dependence of the one-loop divergences in $6D$, ${\cal N} = (1,0)$ abelian theory

We study the gauge dependence of the one-loop effective action for the abelian $6D$, ${\cal N}=(1,0)$ supersymmetric gauge theory formulated in harmonic superspace. We introduce the superfield $ξ$-gauge, construct the corresponding gauge superfield propagator, and calculate the one-loop two-and three-point Green functions with two external hypermultiplet legs. We demonstrate that in the general $ξ$-gauge the two-point Green function of the hypermultiplet is divergent, as opposed to the Feynman gauge $ξ=1$. The three-point Green function with two external hypermultiplet legs and one leg of the …

Relation between two-point Green functions of ${\cal N}=1$ SQED with $N_f$ flavors, regularized by higher derivatives, in the three-loop approximation

We verify the identity which relates the two-point Green functions of ${\cal N}=1$ SQED with $N_f$ flavors, regularized by higher derivatives, by explicit calculations in the three-loop approximation. This identity explains why in the limit of the vanishing external momentum the two-point Green function of the gauge superfield is given by integrals of double total derivatives in the momentum space. It also allows to derive the NSVZ $β$-function exactly in all loops if the renormalization group functions are defined in terms of the bare coupling constant. In order to verify the considered ident…

Effective operators in SUSY, superfield constraints and searches for a UV completion

We discuss the role of a class of higher dimensional operators in 4D N=1 supersymmetric effective theories. The Lagrangian in such theories is an expansion in momenta below the scale of "new physics" ($Λ$) and contains the effective operators generated by integrating out the "heavy states" above $Λ$ present in the UV complete theory. We go beyond the "traditional" leading order in this momentum expansion (in $\partial/Λ$). Keeping manifest supersymmetry and using superfield {\it constraints} we show that the corresponding higher dimensional (derivative) operators in the sectors of chiral, line…

The all-loop perturbative derivation of the NSVZ $β$-function and the NSVZ scheme in the non-Abelian case by summing singular contributions

The perturbative all-loop derivation of the NSVZ $β$-function for ${\cal N}=1$ supersymmetric gauge theories regularized by higher covariant derivatives is finalized by calculating the sum of singularities produced by quantum superfields. These singularities originate from integrals of double total derivatives and determine all contributions to the $β$-function starting from the two-loop approximation. Their sum is expressed in terms of the anomalous dimensions of the quantum gauge superfield, of the Faddeev--Popov ghosts, and of the matter superfields. This allows obtaining the NSVZ equation …

On supersymmetric gauge theories with higher derivatives and nonlocal terms in the matter sector

In this work, we consider local and nonlocal higher-derivative generalizations of the super-Chern-Simons theory and four-dimensional SQED. In contrast to previous studies, the models studied here also have higher-derivative terms in the matter sector. For these models, we calculate the one-loop superfield effective potential.

Superfield Approach To Nilpotent Symmetries For QED From A Single Restriction: An Alternative To The Horizontality Condition

We derive together the exact local, covariant, continuous and off-shell nilpotent Becchi-Rouet-Stora-Tyutin (BRST) and anti-BRST symmetry transformations for the U(1) gauge field (A_μ), the (anti-)ghost fields ((\bar C)C) and the Dirac fields (ψ, \barψ) of the Lagrangian density of a four (3 + 1)-dimensional QED by exploiting a single restriction on the six (4, 2)-dimensional supermanifold. A set of four even spacetime coordinates x^μ(μ= 0, 1, 2, 3) and two odd Grassmannian variables θand \barθparametrize this six dimensional supermanifold. The new gauge invariant restriction on the above supe…

Two-loop finiteness of self-energies in higher-derivative SQED3

In the superfield formalism, two higher-derivative kinetic operators (Lee-Wick operators) are implemented into the standard three dimensional supersymmetric quantum electrodynamics for improving its ultraviolet behavior. It is shown in particular that the ghosts associated with these Lee-Wick operators allow to remove all ultraviolet divergences in the scalar and gauge self-energies at two-loop level.