Relativistic interactions for meson-nucleon systems: applications in the theory of nuclear reactions
It is shown that the method of unitary clothing transformations (UCT) developed in [1, 2] and applied to nuclear physics problems [3, 4], gives a fresh look at constructing interactions between the "clothed'' nucleons, these quasiparticles with the properties of physical nucleons.
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irk-123456789-1070932016-10-14T03:02:18Z Relativistic interactions for meson-nucleon systems: applications in the theory of nuclear reactions Shebeko, A.V. Frolov, P.A. Dubovik, E.A. Section C. Theory of Elementary Particles. Cosmology It is shown that the method of unitary clothing transformations (UCT) developed in [1, 2] and applied to nuclear physics problems [3, 4], gives a fresh look at constructing interactions between the "clothed'' nucleons, these quasiparticles with the properties of physical nucleons. Показано, что метод унитарных одевающих преобразований (УОП), развитый в работах [1,2] и применённый к задачам ядерной физики [3,4], позволяет по-новому взглянуть на построение взаимодействий между "одетыми'' нуклонами, этими квазичастицами со свойствами физических нуклонов. Показано, що метод унітарних одягаючих перетворень (УОП), розроблений в працях [1,2] та застосований до задач ядерної фізики [3,4], дозволяє по-новому поглянути на побудову взаємодії між "одягненими'' нуклонами, цими квазічастинками з властивостями фізичних нуклонів. 2012 Article Relativistic interactions for meson-nucleon systems: applications in the theory of nuclear reactions / A.V. Shebeko, P.A. Frolov, E.A. Dubovik // Вопросы атомной науки и техники. — 2012. — № 1. — С. 188-192. — Бібліогр.: 5 назв. — англ. 1562-6016 PACS: 21.45.Bc, 11.30.Cp, 13.75.Cs http://dspace.nbuv.gov.ua/handle/123456789/107093 en Вопросы атомной науки и техники Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
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Section C. Theory of Elementary Particles. Cosmology Section C. Theory of Elementary Particles. Cosmology Shebeko, A.V. Frolov, P.A. Dubovik, E.A. Relativistic interactions for meson-nucleon systems: applications in the theory of nuclear reactions Вопросы атомной науки и техники |
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It is shown that the method of unitary clothing transformations (UCT) developed in [1, 2] and applied to nuclear physics problems [3, 4], gives a fresh look at constructing interactions between the "clothed'' nucleons, these quasiparticles with the properties of physical nucleons. |
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Article |
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Shebeko, A.V. Frolov, P.A. Dubovik, E.A. |
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Shebeko, A.V. Frolov, P.A. Dubovik, E.A. |
author_sort |
Shebeko, A.V. |
title |
Relativistic interactions for meson-nucleon systems: applications in the theory of nuclear reactions |
title_short |
Relativistic interactions for meson-nucleon systems: applications in the theory of nuclear reactions |
title_full |
Relativistic interactions for meson-nucleon systems: applications in the theory of nuclear reactions |
title_fullStr |
Relativistic interactions for meson-nucleon systems: applications in the theory of nuclear reactions |
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Relativistic interactions for meson-nucleon systems: applications in the theory of nuclear reactions |
title_sort |
relativistic interactions for meson-nucleon systems: applications in the theory of nuclear reactions |
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Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
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2012 |
topic_facet |
Section C. Theory of Elementary Particles. Cosmology |
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http://dspace.nbuv.gov.ua/handle/123456789/107093 |
citation_txt |
Relativistic interactions for meson-nucleon systems: applications in the theory of nuclear reactions / A.V. Shebeko, P.A. Frolov, E.A. Dubovik // Вопросы атомной науки и техники. — 2012. — № 1. — С. 188-192. — Бібліогр.: 5 назв. — англ. |
series |
Вопросы атомной науки и техники |
work_keys_str_mv |
AT shebekoav relativisticinteractionsformesonnucleonsystemsapplicationsinthetheoryofnuclearreactions AT frolovpa relativisticinteractionsformesonnucleonsystemsapplicationsinthetheoryofnuclearreactions AT dubovikea relativisticinteractionsformesonnucleonsystemsapplicationsinthetheoryofnuclearreactions |
first_indexed |
2025-07-07T19:29:09Z |
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2025-07-07T19:29:09Z |
_version_ |
1837017648745938944 |
fulltext |
RELATIVISTIC INTERACTIONS FOR MESON-NUCLEON
SYSTEMS: APPLICATIONS IN THE THEORY OF NUCLEAR
REACTIONS
A.V. Shebeko 1∗, P.A. Frolov 2, E.A. Dubovik 2
1National Science Center “Kharkov Institute of Physics and Technology”, 61108, Kharkov, Ukraine
2Institute of Electrophysics and Radiation Technologies, 61002, Kharkov, Ukraine
(Received October 31, 2011)
It is shown that the method of unitary clothing transformations (UCT) developed in [1, 2] and applied to nuclear
physics problems [3, 4], gives a fresh look at constructing interactions between the “clothed” nucleons, these quasi-
particles with the properties of physical nucleons.
PACS: 21.45.Bc, 11.30.Cp, 13.75.Cs
1. SOME RECOLLECTIONS
Our departure point is the Hamiltonian of a system of
interacting mesons and nucleons that can be written
as
H =
∞∑
C=0
∞∑
A=0
HCA, (1)
HCA =
∫∑
HCA(1′, 2′, ..., n′
C ; 1,2,...,nA)
× a†(1′)a†(2′)...a†(n′
C)a(nA)...a(2)a(1), (2)
where the capital C(A) denotes particle-creation (an-
nihilation) number for operator substructure HCA
and
HCA(1′, ..., C; 1,..., A)
= δ(�p′1 + ...+ �p′C − �p1 − ...− �pA)
× hCA(p′1μ
′
1ξ
′
1...p
′
Cμ
′
Cξ
′
C ; p1μ1ξ1...pAμAξA), (3)
where c-number coefficients hCA do not contain delta
function and a†[a](n) = a†[a](�pn, μn, ξn) is a cre-
ation [annihilation] operator for particle of species ξn
with momentum �pn and polarization μn.
In turn,
HCA =
∫
HCA(�x)d�x ⇒ H =
∫
H(�x)d�x (4)
with density
H(�x) =
∞∑
C=0
∞∑
A=0
HCA(�x). (5)
For example, in case with C = A = 2 we have
H22(1′, 2′; 1, 2) = δ(�p′1 + �p′2 − �p1 − �p2)h(1′2′; 12) (6)
and
H22(�x) =
1
(2π)3
∫∑
exp[−i(�p′1 + �p′2 − �p1 − �p2)�x]
× h(1′2′; 12)a† (1′) a† (2′) a (2)a (1) . (7)
The operator H , being divided into the no-
interaction part HF and the interaction HI , owing
to its translational invariance allowsHI to be written
as
HI =
∫
HI(�x)d�x. (8)
Our consideration is focused upon various field mod-
els (local and nonlocal) in which the interaction den-
sity HI(�x) consists of scalar Hsc(�x) and nonscalar
Hnsc(�x) contributions:
HI(�x) = Hsc(�x) +Hnsc(�x), (9)
where the property to be a scalar means
UF (Λ, b)Hsc(x)U−1
F (Λ, b) = Hsc(Λx+ b),
∀ x = (t, �x) (10)
for all Lorentz transformations Λ and spacetime
shifts b.
As an illustration, in case of the vector mesons (ρ
and ω) we have
Vv = V (1)
v + V (2)
v ,
V (1)
v =
∫
d�xHsc(�x), V (2)
v =
∫
d�xHnsc(�x),
Hsc(�x) = gvψ̄(�x)γμψ(�x)ϕμ
v (�x)
+
fv
4m
ψ̄(�x)σμνψ(�x)ϕμν
v (�x),
∗Corresponding author E-mail address: shebeko@kipt.kharkov.ua
188 PROBLEMS OF ATOMIC SCIENCE AND TECHNOLOGY, 2012, N 1.
Series: Nuclear Physics Investigations (57), p. 188-192.
Hnonsc(�x) =
g2
v
2m2
v
ψ̄(�x)γ0ψ(�x)ψ̄(�x)γ0ψ(�x)
+
f2
v
4m2
ψ̄(�x)σ0iψ(�x)ψ̄(�x)σ0iψ(�x),
where ϕμν
v (�x) = ∂μϕν
v(�x) − ∂νϕμ
v (�x) is a tensor of a
vector field in Schrödinger (S) picture. Such a situ-
ation is typical of theories with derivative couplings
or spins j ≥ 1.
2. BOOST GENERATORS. RELATIVISTIC
INVARIANCE (RI) AS A WHOLE
To free ourselves from any dependence on pre-
existing field theories, the three boost operators �N =
(N1, N2, N3) can be written as:
�N =
∞∑
C=0
∞∑
A=0
�NCA, (11)
�NCA =
∫∑
�NCA(1′, 2′, ..., n′
C ; 1, 2, ..., nA)
× a†(1′)a†(2′)...a†(n′
C)a(nA)...a(2)a(1). (12)
We have developed an algebraic procedure to find
links between coefficients HCA and �NCA, compatible
with commutations
[Pi, Pj ] = 0, [Ji, Jj ] = iεijkJk, [Ji, Pj ] = iεijkPk,
[�P ,H ] = 0, [ �J,H ] = 0, [Ji, Nj] = iεijkNk,
[Pi, Nj] = iδijH, [H, �N ] = i �P , [Ni,Nj ] = −iεijkJk,
(i, j, k = 1, 2, 3),
where �P = (P 1, P 2, P 3) and �J = (J1, J2, J3) are lin-
ear and angular momentum operators.
For instant form of the relativistic dynamics after
Dirac only Hamiltonian and boost operators carry in-
teractions, viz.,
H = HF +HI , �N = �NF + �NI ,
while �P = �PF and �J = �JF .
How one can build up operators HI and �NI is
shown in [4]. Here we would like to present only a
free part of the fermion boost operator
�Nferm = �Norb
ferm + �Nspin
ferm,
where
�Norb
ferm =
i
2
∫∑
d�pE�p
(
∂b†(�pμ)
∂�p
b(�pμ)
−b†(�pμ)
∂b(�pμ)
∂�p
∂d†(�pμ)
∂�p
d(�pμ) − d†(�pμ)
∂d(�pμ)
∂�p
)
,
�Nspin
ferm = −1
2
∫∑
d�p �p× χ†(μ)�σχ(μ)
E�p +m
× (
b†(�pμ)b(�pμ) + d†(�pμ)d(�pμ)
)
.
Here E�p =
√
�p2 +m2 is the nucleon energy and χ(μ)
is the Pauli spinor.
3. METHOD OF UCTs IN ACTION
Method in question is aimed at expressing a field
Hamiltonian through the so-called clothed-particle
creation (annihilation) operators αc, e.g., a†c(ac),
b†c(bc) and d†c(dc) via UCTs W (αc) = W (α) =
expR, R = −R† in similarity transformation
α = W (αc)αcW
†(αc) (13)
that connect primary set α in bare-particle represen-
tation (BPR) with the new operators in CPR.
A key point of the clothing procedure is to remove
the so-called bad terms from Hamiltonian
H ≡ H(α) = HF (α) +HI(α)
= W (αc)H(αc)W †(αc) ≡ K(αc). (14)
By definition, such terms prevent physical vacuum
|Ω〉 (H lowest eigenstate) and one-clothed-particle
states |n〉c = a†c(n)|Ω〉 to be H eigenvectors for all
n included. Bad terms occur every time when any
normally ordered product
a†(1′)a†(2′)...a†(n′
C)a(nA)...a(2)a(1)
of class [C.A] embodies, at least, one substructure ∈
[k.0] (k = 1, 2...) or/and [k.1] (k = 2, 3, ...). In this
context all primary Yukawa-type (trilinear) couplings
shown above should be eliminated.
Respectively, let us write for boson–fermion sys-
tem
HI(α) = V (α) + Vren(α) (15)
with primary (trial) interaction V (α) = Vbad + Vgood
“good” (e.g., ∈ [k.2]) as antithesis of “bad” while
Vren(α) ∼ [1.1] + [0.2] + [2.0] “mass renormalization
counterterms”. It turns out that latter are important
to ensure RI as a whole, i.e., in Dirac sense.
In order to compare our calculations with those
by Bonn group [5] we have employed V (α) = Vs +
Vps + Vv. Then clothing itself is prompted by
H(α) = K(αc)
≡W (αc)[HF (αc) + Vv(αc) + Vren(αc)]W †(αc)
(16)
or
K(αc) = HF (αc) + V (1)
v (αc) + [R,HF ] + V (2)
v (αc)
+ [R, V (1)
v ] +
1
2
[R, [R,HF ]] + [R, V (2)
v ]
+
1
2
[R, [R, V (1)
v ] + ... (17)
and requiring [R,HF ] = −V (1)
v for the operator R of
interest to get
H = K(αc) = KF +KI (18)
189
with a new free part KF = HF (αc) ∼ a†cac and inter-
action
KI =
1
2
[R, V (1)
v ] + V (2)
v +
1
3
[R, [R, V (1)
v ]] + ... (19)
between clothed particles.
Moreover, after modest effort we have
1
2
[
R, V (1)
v
]
(NN → NN)
= Kv(NN → NN) +Kcont(NN → NN), (20)
where the operator Kcont(NN → NN) may be as-
sociated with a contact interaction since it does not
contain any propagators (details see in Refs. [3]). It
has turned out that this operator cancels completely
non-scalar operator V (2).
In parallel, we have
�N(α) = �B(αc)
= W (αc){ �NF (α) + �NI(α) + �Nren(α)}W †(αc) (21)
with
�NI = −
∫
�xVv(�x)d�x =
−
∫
�x{V (1)
v (�x) + V (2)
v (�x)}d�x = �N
(1)
I + �N
(2)
I . (22)
As before (see Refs. [2,3]) we find that the boost
generator in CPR acquires the structure similar to
K(αc):
�B(αc) = �BF + �BI . (23)
Here �BF = �NF (αc) boost operator for noninteract-
ing clothed particles (in our case fermions and vector
mesons) and �BI incorporates contributions induced
by interactions between them
�BI = +
1
2
[R, �N (1)
I ] +
1
3
[R, [R, �N (1)
I ]] + ...
4. RELATIVISTIC INTERACTIONS
Operator KI contains only interactions responsible
for physical processes, these quasipotentials between
the clothed particles, e.g.,
KI ∼ a†cb
†
cacbc(πN → πN)+ b†cb
†
cbcbc(NN → NN)
+ d†cd
†
cdcdc(N̄N̄ → N̄N̄) + ...
+ [a†ca
†
cbcdc +H.c.](NN̄ ↔ 2π) + ...
+ [a†cb
†
cb
†
cbcbc +H.c.](NN ↔ πNN) + ... (24)
After normal ordering of fermion operators we de-
rive NN → NN interaction operator (mediated, for
instance, by pions)
KNN =
∫
d�p1d�p2d�p
′
1d�p
′
2VNN (�p ′
1, �p
′
2; �p1, �p2)
× b†c(�p
′
1)b
†
c(�p
′
2)bc(�p1)bc(�p2), (25)
VNN (�p ′
1, �p
′
2; �p1, �p2) = −1
2
g2
(2π)3
m2√
E�p1E�p2E�p ′
1
E�p ′
2
× δ(�p ′
1 + �p ′
2 − �p1 − �p2)
× ū(�p ′
1)γ5u(�p1)
1
(p1 − p′1)2 − μ2
ū(�p ′
2)γ5u(�p2). (26)
The corresponding relativistic and properly sym-
metrized NN quasipotential is
ṼNN (�p ′
1, �p
′
2; �p1, �p2)
=
〈
b†c(�p
′
1)b
†
c(�p
′
2)Ω | KNN | b†c(�p1)b†c(�p2)Ω
〉
, (27)
or through covariant (Feynman-like) “propagators”:
ṼNN (�p ′
1, �p
′
2; �p1, �p2) = −1
2
g2
(2π)3
m2
2
√
E�p1E�p2E�p ′
1
E�p ′
2
× δ(�p ′
1 + �p ′
2 − �p1 − �p2)
× ū(�p ′
1)γ5u(�p1)
1
2
{
1
(p1 − p′1)2 − μ2
+
1
(p2 − p′2)2 − μ2
}
ū(�p ′
2)γ5u(�p2) − (1 ↔ 2). (28)
Distinctive feature of potential (28) is the pres-
ence of covariant (Feynman-like) “propagator”:
1
2
{
1
(p1 − p′1)2 − μ2
+
1
(p2 − p′2)2 − μ2
}
.
On the energy shell for NN scattering, that is
Ei ≡ E�p1 + E�p2 = E�p ′
1
+ E�p ′
2
≡ Ef ,
this expression is converted into the genuine Feynman
propagator.
These quasipotentials form the kernel of the in-
tegral equation for the nucleon-nucleon scattering R-
matrix:
〈1′2′| R̄(E) |12〉 = 〈1′2′| K̄NN |12〉
+
∫
34
∑
〈1′2′| K̄NN |34〉 〈34| R̄(E) |12〉
E − E3 − E4
(29)
with R̄(E) = R(E)/2 (K̄NN = KNN/2), symbol
∫
34
∑
implies the p.v. integration.
5. DEUTERON PROPERTIES
The deuteron state |Ψd(�P )〉 ∈ H2N in the CPR sat-
isfies the eigenvalue equation
[KF (αc) +KI(αc)]|Ψd(�P )〉 = Ed|Ψd(�P )〉 (30)
with Ed =
√
m2
d + �P 2, where �P is the total deuteron
momentum, md = mp +mn−εd is the deuteron mass
and εd represents the binding energy of the deuteron.
Using the approximation with KI(αc) =
K(NN → NN) = KNN we arrive to a simpler eigen-
value problem
[
KN
F +KNN
] |�P ;M〉 = Ed|�P ;M〉 (31)
190
in the subspace H2N spanned onto the basis b†cb†c|Ω〉
with KNN ∼ b†cb
†
cbcbc. Here M denotes the deuteron
spin projection on the quantization axis.
The solution of this equation can be represented
as
|�P ;M〉 =
∫
d�p1d�p2DM (�P ; �p1μ1, �p2μ2)
× b†c(�p1μ1)b†c(�p2μ2)|Ω〉 (32)
with the coefficients DM (�P ; �p1μ1, �p2μ2) = δ(�P −
�p1 − �p2)ψM (�p1μ1, �p2μ2) that have the property
ψM (1, 2) = −ψM (2, 1).
In the deuteron rest frame the equation (31) takes
the form
|ψM 〉 =
[
md −KN
F
]−1
KNN |ψM 〉, (33)
where
|ψM 〉 ≡ |�P = 0;M〉
=
∫
d�pψM (�pμ1,−�pμ2)b†c(�pμ1)b†c(−�pμ2)|Ω〉. (34)
Using the basis vectors |p(lS)JMJ , TMT 〉 introduced
in our previous paper [3] (see Appendix B) the vector
|ψM 〉 can be written as
|ψM,TMT 〉
=
1√
2
∑∫
p2dp |p(lS)1M,TMT 〉ψlST (p), (35)
since the deuteron has the invariant spin equal J = 1.
In Eq. (35) the permissible values of the quantum
numbers l, S and T are restricted to the property
Pferm|ψM,TMT 〉 = |ψM,TMT 〉 (36)
with respect to the space inversion (see Appendix B
in [1], where one can find formula (114) for the parity
operator Pferm of the nucleon field in the CPR). In
fact, there are only the two combinations of T , S and
l, namely, T = 0, S = 1 and l = 0, 2. Respectively,
|ψM,00〉 ≡ |ψM 〉
=
1√
2
∑
l=0,2
∫
p2dp |p(l1)1M〉ψl(p). (37)
At this point, we accept the normalization condi-
tion
〈ψM ′ |ψM 〉 = δM ′M (38)
that implies
∞∫
0
p2dp
[
ψ2
0(p) + ψ2
2(p)
]
= 1. (39)
Substituting the decomposition (37) into the
equation (33) we get the set of homogeneous integral
equations for “radial” components ψl(p) (l = 0, 2):
ψl(p) =
1
md − 2E�p
×
∑
l′
∫
k2dkV J=S=1,T=0
l l′ (p, k)ψl′(k). (40)
In a moving frame the corresponding eigenvector
that belongs to the value Ed =
√
�P 2 +m2
d can be de-
termined either by solving directly the equation (31)
or using the relation
|�P ;M〉 = exp[i�β �B(αc)]|ψM 〉. (41)
The boost operator �B(αc) = �BF (αc) + �BI(αc), de-
termined in the CPR by
�B(αc) = W (αc) �N (αc)W †(αc), (42)
consists of the free �BF and interaction �BI parts. Here
�N is the total boost operator for interacting fields.
Perhaps, one should note that the required
P̂μ|�P ;M〉 = Pμ|�P ;M〉 (43)
follows from the property of the energy-momentum
operator P̂μ = (H, P̂ 1, P̂ 2, P̂ 3) to be the four-vector.
The parameters (β1, β2, β3) = �β for the Lorentz
transformation md(1, 0, 0, 0) ⇒ (P 0, P 1, P 2, P 3) = P
are related to the “velocity” �v = �P/P 0 of the moving
frame as
�β = β�n, �n = �v/v, tanhβ = v. (44)
As in our previous paper [3] we continue compar-
ison of UCT approach with results of the Bonn
group [5]. In particular, the low-energy pa-
rameters of NN scattering and deuteron prop-
erties are presented in Table 1 and the fig-
ure.The best-fit parameters are collected in Table 2.
Table 1. Deuteron and low-energy parameters. The
experimental values are from Table 4.2 of Ref. [5]
Parameter Bonn B UCT Experiment
as (fm) −23.71 −23.57 −23.748±0.010
rs (fm) 2.71 2.65 2.75±0.05
at (fm) 5.426 5.44 5.419±0.007
rt (fm) 1.761 1.79 1.754±0.008
εd (MeV) 2.223 2.224 2.224575
PD (%) 4.99 4.89
Deuteron wave function components ψd
0(p) = u(p)
and ψd
2(p) = w(p). Solid (dotted) curves calculated
for the Bonn B (UCT) potential
191
Table 2. The best-fit parameters for the two models. The row Potential B (UCT ) taken from Table A.1
in [5] (obtained by least squares fitting to OBEP values in Table 1 of Ref. [3] including deuteron binding
energy and low-energy parameters). All masses are in MeV , and nb = 1 except for nρ = nω = 2
Model Meson π η ρ ω δ σ, T = 0 (T = 1)
g2/4π [f/g] 14.4 3 0.9 [6.1] 24.5 2.488 18.3773 (8.9437)
Potential B Λ 1700 1500 1850 1850 2000 2000 (1900)
m 138.03 548.8 769 782.6 938 720 (550)
g2/4π [f/g] 13.395 5.0 1.2 [6.1] 17.349 5.0 22.015 (5.514)
UCT Λ 2500 1219 1593 2494 2169 1200 (2500)
m 138.03 548.8 769 782.6 938 720 (550)
6. CONCLUSIONS
Starting from a total Hamiltonian for interacting me-
son and nucleon fields, we come to the Hamiltonian
and boost generator in the CPR whose interaction
parts consist of new relativistic interactions responsi-
ble for physical (not virtual) processes, particularly,
in the system of bosons (π−, η−, ρ−, ω−, δ− and
σ−mesons) and fermions (nucleons and antinucle-
ons).
Using the unitary equivalence of CPR to BPR,
we have seen how the NN scattering problem in
QFT can be reduced to the three-dimensional LS-
type equation for the T -matrix in momentum space.
The equation kernel is given by clothed two-nucleon
interaction of class [2.2].
Special attention has been paid to the elimina-
tion of auxiliary field components. We encounter such
a necessity for interacting vector and fermion fields
when in accordance with the canonical formalism the
interaction Hamiltonian density embodies not only a
scalar contribution but nonscalar terms too.
Being concerned with constructing two-nucleon
states and their angular-momentum decomposition
we have not used the so-called separable ansatz. The
clothed two-nucleon partial waves have been built
up as common eigenstates of the field total angular-
momentum generator and its polarization (fermionic)
part.
As a whole, persistent clouds of virtual particles
are no longer explicitly contained in CPR, and their
influence is included in properties of clothed particles
(these quasiparticles of the UCT method). In addi-
tion, we would like to stress that problem of the mass
and vertex renormalizations is intimately interwoven
with constructing the interactions between clothed
nucleons.
References
1. A. Shebeko, M. Shirokov. Unitary transforma-
tions in quantum field theory and bound states
// Phys. Part. Nucl. 2001, v. 32, p. 31-95.
2. V. Korda, L. Canton, A. Shebeko. Relativistic
interactions for the meson-two-nucleon system in
the clothed- particle unitary representation //
Ann. Phys. 2007, v. 322, p. 736-768.
3. I. Dubovyk, O. Shebeko. The method of unitary
clothing transformations in the theory of nucleon-
nucleon scattering // Few Body Syst. 2010, v. 48,
p. 109-142.
4. A.V. Shebeko, P.A. Frolov. A possible way for
constructing generators of the Poincaré group in
quantum field theory // Few Body Syst. 2011,
DOI:10.1007/s00601-011-0262-5.
5. R. Machleidt. The meson theory of nuclear forces
and nuclear structure // Adv. Nucl. Phys. 1989,
v. 19, p. 189-376.
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