Proton polarization in photodisintegration of nuclei D, ³He, ⁴He
The result of proton polarization measurements (period 1993-2000) in the photodisintegration of the nuclei D, ³He, ⁴He at the photon energies E=350-750 MeV are presented. The proton polarization was measured on the 2 GeV linac NSC KIPT with a carbon polarimeter and a magnetic spectrometer. The proto...
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Національний науковий центр «Харківський фізико-технічний інститут» НАН України
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| Cite this: | Proton polarization in photodisintegration of nuclei D, ³He, ⁴He / O.G. Konovalov, S.T. Lukjanenko, S.V. Marekhin, R.I. Pomatsaljuk, P.V. Sorokin, A.A. Zybalov // Вопросы атомной науки и техники. — 2001. — № 1. — С. 11-12. — Бібліогр.: 11 назв. — англ. |
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Konovalov, O.G. Lukjanenko, S.T. Marekhin, S.V. Pomatsaljuk, R.I. Sorokin, P.V. Zybalov, A.A. 2015-03-17T11:07:33Z 2015-03-17T11:07:33Z 2001 Proton polarization in photodisintegration of nuclei D, ³He, ⁴He / O.G. Konovalov, S.T. Lukjanenko, S.V. Marekhin, R.I. Pomatsaljuk, P.V. Sorokin, A.A. Zybalov // Вопросы атомной науки и техники. — 2001. — № 1. — С. 11-12. — Бібліогр.: 11 назв. — англ. 1562-6016 PACS: 24.70. + s, 25.20. · x. https://nasplib.isofts.kiev.ua/handle/123456789/78436 The result of proton polarization measurements (period 1993-2000) in the photodisintegration of the nuclei D, ³He, ⁴He at the photon energies E=350-750 MeV are presented. The proton polarization was measured on the 2 GeV linac NSC KIPT with a carbon polarimeter and a magnetic spectrometer. The proton polarization for the nuclei ³He and ⁴He is first measured and analyzed within the framework of "quasi-deuteron" model. en Національний науковий центр «Харківський фізико-технічний інститут» НАН України Вопросы атомной науки и техники IHEPNF NSC KIPT in the last decade Proton polarization in photodisintegration of nuclei D, ³He, ⁴He Поляризация протонов в фотодезинтеграции ядер D, ³He, ⁴He Article published earlier |
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Digital Library of Periodicals of National Academy of Sciences of Ukraine |
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Proton polarization in photodisintegration of nuclei D, ³He, ⁴He |
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Proton polarization in photodisintegration of nuclei D, ³He, ⁴He Konovalov, O.G. Lukjanenko, S.T. Marekhin, S.V. Pomatsaljuk, R.I. Sorokin, P.V. Zybalov, A.A. IHEPNF NSC KIPT in the last decade |
| title_short |
Proton polarization in photodisintegration of nuclei D, ³He, ⁴He |
| title_full |
Proton polarization in photodisintegration of nuclei D, ³He, ⁴He |
| title_fullStr |
Proton polarization in photodisintegration of nuclei D, ³He, ⁴He |
| title_full_unstemmed |
Proton polarization in photodisintegration of nuclei D, ³He, ⁴He |
| title_sort |
proton polarization in photodisintegration of nuclei d, ³he, ⁴he |
| author |
Konovalov, O.G. Lukjanenko, S.T. Marekhin, S.V. Pomatsaljuk, R.I. Sorokin, P.V. Zybalov, A.A. |
| author_facet |
Konovalov, O.G. Lukjanenko, S.T. Marekhin, S.V. Pomatsaljuk, R.I. Sorokin, P.V. Zybalov, A.A. |
| topic |
IHEPNF NSC KIPT in the last decade |
| topic_facet |
IHEPNF NSC KIPT in the last decade |
| publishDate |
2001 |
| language |
English |
| container_title |
Вопросы атомной науки и техники |
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Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
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Article |
| title_alt |
Поляризация протонов в фотодезинтеграции ядер D, ³He, ⁴He |
| description |
The result of proton polarization measurements (period 1993-2000) in the photodisintegration of the nuclei D, ³He, ⁴He at the photon energies E=350-750 MeV are presented. The proton polarization was measured on the 2 GeV linac NSC KIPT with a carbon polarimeter and a magnetic spectrometer. The proton polarization for the nuclei ³He and ⁴He is first measured and analyzed within the framework of "quasi-deuteron" model.
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1562-6016 |
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https://nasplib.isofts.kiev.ua/handle/123456789/78436 |
| citation_txt |
Proton polarization in photodisintegration of nuclei D, ³He, ⁴He / O.G. Konovalov, S.T. Lukjanenko, S.V. Marekhin, R.I. Pomatsaljuk, P.V. Sorokin, A.A. Zybalov // Вопросы атомной науки и техники. — 2001. — № 1. — С. 11-12. — Бібліогр.: 11 назв. — англ. |
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2025-11-27T05:32:09Z |
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2025-11-27T05:32:09Z |
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1850802153694691328 |
| fulltext |
PROTON POLARIZATION
IN PHOTODISINTEGRATION OF NUCLEI D, 3He, 4He
O.G. Konovalov, S.T. Lukjanenko, S.V. Marekhin,
R.I. Pomatsaljuk, P.V. Sorokin, A.A. Zybalov
National Science Center “Kharkov Institute of Physics and Technology”, Kharkov, Ukraine
The result of proton polarization measurements (period 1993-2000) in the photodisintegration of the nuclei D,
3He, 4He at the photon energies E=350-750 MeV are presented. The proton polarization was measured on the 2 GeV
linac NSC KIPT with a carbon polarimeter and a magnetic spectrometer. The proton polarization for the nuclei 3He
and 4He is first measured and analyzed within the framework of "quasi-deuteron" model.
PACS: 24.70. + s, 25.20. ⋅ x.
1. INTRODUCTION
Investigation of the polarization observations in pho-
todisintegration reactions is an effective method for a
study of the mechanism of electromagnetic interaction
in nuclei, in particular, the NN-correlations in nuclei.
Levinger [1] has made a great contribution in the inves-
tigations of the mechanism of photonuclear interactions
owing to his model of the dominant role of (np)-correla-
tions (quasi-deuterons) in the process of photon absorp-
tion in nuclei. This model was examined by means of
the cross-section measurements of a photon absorption
in nuclei with the registration of emitted nucleons in co-
incidence [2]. These measurements confirmed
Levinger’s conclusion about the dominant contribution
of the photon absorption by (np)-correlations in the
cross sections of a photonuclear absorption and small
addition from γ(nn) and γ(pp)-interactions. The further
step may be studying the properties of quasi-deuterons
in nuclei, the structure of their wave functions and the
mechanism of γ(nn)-interactions in various nuclei in
comparison with the mechanism of the body photodisin-
tegration of a free deuteron. Of great interest is the in-
vestigation of interactions of photons with lightest nu-
clei 3He and 4He. It is expected that influence of a nucle-
ar 3He, 4He matter on the properties of (np)-pairs will be
minimal and the characteristic of a quasi-deuteron and a
free deuteron are rather near. The γD→np reaction has
been investigated more than 60 years and already one
obtained a rich theoretical and experimental material.
W. Leidemann and H. Arenhovel [3,4] have made the
detailed theoretical calculations of the cross-section and
polarization parameters at Eγ<350 MeV taking into ac-
count the meson-exchange currents, isobar configura-
tions of N∆, ∆∆-type, relativistic corrections with vari-
ous NN-potentials. It has been shown that the non-zero
value of the proton polarization is mainly due to the
contribution of N∆-isobar configurations. Such calcula-
tions are absent for γ(np)-processes in nuclei and there
is no possibility to obtain the information about pecu-
liarities of these processes in comparison with γD-inter-
action. So, there is the possibility to compare the results
of proton polarization for γD→np and γ(np)-processes
by measuring the proton polarization under identical
kinematical conditions. These measurements were first-
ly made at NSC KIPT on the 2 GeV linac.
2. EXPERIMENTAL ARRANGEMENT
Fig. 1 shows the layout of the experimental arrange-
ment. The detailed description of the experimental ar-
rangement is presented in [5].
Fig. 1. Experimental layout: 1-magnetic lenses, 2-
secondary emission monitor, 3-tantalum radiator, 4-
cleaning magnet, 5-lead collimator, 6-liquid nuclear
target, 7-Wilson quantometer, 8-magnetic spectrometer,
9-proton carbon polarimeter, SC-spark chambers, C1,
C2, C3-scintillation counters, 12C-carbon scatterer, Cu-
copper moderator
The liquid deuterium target having 40 mm in diame-
ter and 200 mm length along a beam is used for mea-
surements of the proton polarization in the reaction γD
→pn. The liquid targets 3He and 4He having 35 mm in
diameter and 120 mm length are employed in polariza-
tion investigations of photodisintegration of lightest nu-
clei [6]. After interaction of a photon beam with a nucle-
ar target the emitted protons are analyzed by the mag-
netic spectrometer with the momentum resolution ∆
p/p=0,2% and are detected by the carbon polarimeter
with wire spark chambers. The data handling involved
the reconstruction of horizontal and vertical projections,
the selection of events of pC-scattering and the calcula-
tion of proton polarization.
3. RESULTS AND DISCUSSION
All proton polarization measurements for the photo-
disintegration of the nuclei 3He and 4He was made in the
kinematic of two-body photodisintegration of a free
deuteron having identical values of the angle Θp and the
momentum p of emitted protons for the reaction γD→np
and γ(np) in the nuclei 3He and 4He. The Fig. 2 presents
the results of proton polarization measurements [5,7,8].
PROBLEMS OF ATOMIC SCIENCE AND TECHNOLOGY. 2001, № 1.
Series: Nuclear Physics Investigations (37), p. 11-12.
11
Fig. 2. The proton polarization in the reactions γD
→np and γ(np) for the nuclei 3He, 4He: ο - the results
[5,7,8],♥ - [9] for the γD-np, • - 3He, ∇ - 4He
The polarization data for the reaction γD→np of [9]
are presented here (Fig. 2a). Our measurements have
been performed with the better statistics and the energy
step ∆Eγ=25 MeV at ∆Eγ=50 MeV from [9]. They con-
firmed the presence of a high value of the proton polar-
ization (P~0,4-0,7) in the reaction γD→np at Eγ=350-
750 MeV. This polarization is not described only by the
pole and meson-exchange diagrams. To describe the
high proton polarization value near 550 MeV T. Kamae
and T. Fujita [10] have used the pole nucleon diagram,
nucleon-resonance diagram with the meson exchange
and the diagram with the dibaryon resonances in the in-
termediate state. Only the consideration of dibaryon res-
onances made it possible to describe the polarization be-
haviour, however, this model failed to reproduce the an-
gular dependences of the Σ-asymmetry measured by the
use of a polarized photon beam [11]. The Fig. 2b shows
the results of proton polarization measurements for the
nuclei 3He and 4He [5,7,8]. These measurements are
made for the first time. For the nucleus 4He there is only
the proton polarization at the energy Eγ=350 MeV
which agrees with the analogous measurement for 3He.
The proton polarization in the photodisintegration of the
nucleus 3He differs from nought (P~0,35-0,45) in all the
energy interval of the measurements. The Fig. 2c
presents the comparison of the proton polarization in the
photodisintegration of nuclei 3He, 4He and a free
deuteron (γD→np). The results of this comparison al-
lowed one to make the next conclusions:
-the signs of the proton polarization in the photodis-
integration of 3He, 4He and the free deuteron coincide
and the values of the polarization are near each other;
-the results of the polarization measurements for the
nuclei 3He, 4He confirm the dominant contribution of
"quasideuteron" mechanism of the photon absorption in
lightest nuclei;
-the polarization measurements with nuclei 3He and
4He show that the effect of influence of a nuclear matter
has not noticeable contribution for lightest nuclei;
-the near values of the polarization in the reactions γ
D→np and the γ(np) in nuclei 3He, 4He can evidence
that the quantum numbers of the free deuteron and
"quasi-deuteron" are equal.
REFERENCES
1. J.S. Levinger. The High Energy Nuclear Photo-
effect // Phys. Rev. 1951, v. 84, 43-51.
2. G. Ricco. Quasi Deuteron Effect. Results and
Perspectives. Proceeding of 6-th Seminar "Elec-
tromagnetic Interactions of Nuclei at Low and
Medium Energies", 1986, Moscow, p. 79-95.
3. W. Leidemann and H. Arenhovel. Photodisinte-
gration of the Deuteron d(γ,p)n in the ∆-Reso-
nance Region // Phys. Let. 1984, B139, p. 22-
26.
4. W. Leidemann and H. Arenhovel. Two-Body
Deuteron Photodisintegration above Pion
Threshold with Dynamic Treatment of ∆-De-
gree of Freedom // Nucl. Phys. 1987, A465, p.
573-614.
5. A.A. Zybalov, S.P. Karasev et al. Proton polar-
ization in reaction of inclusive photodisintegra-
tion of nucleus 3He // Jour. Nucl. Phys. 1995, v.
58, №6, p. 966-969 (in Russian).
6. V.A. Get'man, A.Ya. Derkach et al. Liquid heli-
um target for investigations with electron and
photon beams // Prib. Tech, Exper. 1989, №5, p.
58–59 (in Russian).
7. O.G. Konovalov, S.P. Karasev et al. Proton Po-
larization in inclusive γ3He→pX reaction. Con-
tribution to the Eighth Symposium on Polariza-
tion Phenomena in Nuclear Physics "Spin",
1994, Bloomington, USA, p. 188-191.
8. A.A. Belyaev, V.A. Get'man et al. Proton polar-
ization in reaction of photodisintegration of nu-
clei 3He, 4He, D in energy range 350-750 MeV
// Ukr. Phys. Jour. 1997, №3, p. 270-273 (in
Ukrainen).
9. T. Kamae, I. Arai et al. Observation of an
Anomalous Structure in proton polarization
from Deuteron photodisintegration // Phys. Rev.
Let. 1977, v. 38, №9, p. 468-471.
10. T. Kamae and T. Fujita. Possible Existence of a
Deeply Bound ∆∆-System // Phys. Rev. Let.
1977, v. 38, №9, p. 471-474.
11. V.P. Barannik, A.S. Bratashevskij et al. Proton
polarization in deuteron disintegration by linear-
ly polarized photons and dibaryon resonances //
Nucl. Phys. 1986, A451, p. 751-767.
O.G. Konovalov, S.T. Lukjanenko, S.V. Marekhin,
R.I. Pomatsaljuk, P.V. Sorokin, A.A. Zybalov
National Science Center “Kharkov Institute of Physics and Technology”, Kharkov, Ukraine
PACS: 24.70. + s, 25.20. x.
1. INTRODUCTION
2. EXPERIMENTAL ARRANGEMENT
3. RESULTS AND DISCUSSION
REFERENCES
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