V.Yu. Shakhmanov, K.V. Stepanyantz / Nuclear Physics B 920 (2017) 345–367 349
The regulator K(x) also satisfies the condition K(0) = 1 and should have sufficiently rapid
growth at infinity.
Also it is necessary to introduce the F
addeev–Popov and Nielsen–Kallosh ghosts and the
Pauli–Villars determinants for regularizing one-loop divergences, which remain after adding the
higher derivative terms. The details of these constructions can be found in [50]. The quantum
corrections considered in this paper do not involve these fields, so that we will not discuss them
in details. We only note that the actions for the P
auli–Villars superfields are quadratic in the
chiral matter superfields. This implies that there are no Yukawa interaction terms including the
Pauli–Villars superfields.
Having in mind the e
xact results derived with the higher derivative regularization for Abelian
supersymmetric theories, it is natural to suggest that the NSVZ relation in the non-Abelian case
is satisfied by the RG functions defined in terms of the bare couplings if the theory is regularized
by higher covariant derivatives. According to [47], the NSVZ equation can be re
written in the
form of the relation (2) between the β-function and the anomalous dimensions of the quantum
gauge superfield, of the Faddeev–Popov ghosts, and of the matter superfields. Eq. (2) implies
existence of the relation between the Green functions of these superfields, which can be written
as
d
d ln
d
−1
−α
−1
0
α,λ=const; p→0
=−
3C
2
−T(R)
2π
−
1
2π
d
d ln
−2C
2
ln G
c
−C
2
ln G
V
+C(R)
i
j
(ln G
φ
)
j
i
/r
α,λ=const;q→0
. (10)
This equation admits a simple graphical interpretation [47]. Namely, let us consider a supergraph
without external lines. If we attach to it two external lines of the background gauge superfield,
then the sum of the diagrams obtained in this way contributes to the function d
−1
− α
−1
0
. From
the other side, various possible cuts of the original supergraph propagators give a set of diagrams
contributing to the two-point functions of the quantum gauge superfields, of the Faddeev–Popov
ghosts, and of the matter superfields that is to G
V
, G
c
, and (G
φ
)
i
j
, respectively. Eq. (10) relates
them to the above described contribution to the function d
−1
−α
−1
0
.
In this paper we v
erify that Eq. (10) is valid for terms proportional to λ
4
0
. Such terms are
present in the functions d
−1
and (G
φ
)
i
j
, which are related to the two-point Green functions of
the background gauge superfield and of the matter superfields, respectively. Namely,
(2)
−S
(2)
gf
=
1
4
d
4
p
(2π)
4
d
4
θφ
∗i
(θ, −p)φ
j
(θ, p)G
φ
(α
0
,λ
0
,/p)
i
j
−
1
8π
tr
d
4
p
(2π)
4
d
4
θ V (θ, −p)∂
2
1/2
V (θ, p) d
−1
(α
0
,λ
0
,/p)+ ....
(11)
The functions G
c
and G
V
are related to the Green functions of the Faddeev–Popov ghosts and of
the quantum gauge superfield. Their definitions are given in [47], but in this paper these functions
are not essential, because they do not contain terms of the considered structure.
If Eq. (10) is v
alid, then the NSVZ scheme is given by the prescription (3). Therefore, we will
also be able to verify Eq. (3) for the considered terms. Note that this check is non-trivial, because
we consider the scheme-dependent contributions to the NSVZ relation.