The linearly polarized photon beam for photonuclear investigations at new NSC KIPT facility
Intensity and polarization spectrums of coherent bremsstrahlung for the designed facility NSC KIPT (project SALO) for two possible channels of output of electron beam from accelerator with the maximal energies of beam 490 and 730 MeV are calculated. It is shown, that at the definite conditions of fo...
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Національний науковий центр «Харківський фізико-технічний інститут» НАН України
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Ganenko, V.B. Vashchenko, G.A. Burdeynyi, D.D. 2017-01-04T19:34:07Z 2017-01-04T19:34:07Z 2007 The linearly polarized photon beam for photonuclear investigations at new NSC KIPT facility / V.B. Ganenko, G.A. Vashchenko, D.D. Burdeynyi // Вопросы атомной науки и техники. — 2007. — № 5. — С. 160-165. — Бібліогр.: 12 назв. — англ. 1562-6016 PACS: 29.27.Hj https://nasplib.isofts.kiev.ua/handle/123456789/110563 Intensity and polarization spectrums of coherent bremsstrahlung for the designed facility NSC KIPT (project SALO) for two possible channels of output of electron beam from accelerator with the maximal energies of beam 490 and 730 MeV are calculated. It is shown, that at the definite conditions of forming the beam it is possible to obtain the CB beams with intensity and polarization, sufficient for conducting of experimental researches in the interval of energies of photons about 400MeV on the beam line with the maximal electron energy about 730 MeV , and in interval about 250 MeV on the beam line with the maximal electron energy about 490 MeV . Розраховані спектри інтенсивності і поляризації когерентного гальмівного випромінювання для проектованої установки ННЦ ХФТІ (проект SALO) для двох можливих каналів виведення електронного пучка з прискорювача з максимальними енергіями пучка 490 і 730 МеВ. Показано, що за певних умов формування можливе отримання пучків КГВ з інтенсивністю і поляризацієй, достатніми для проведення експериментальних досліджень в інтервалі енергій фотонів до 400 МеВ на пучковій лінії з максимальною енергією електронів до 730 МеВ, і в інтервалі до 250 МеВ на пучковій лінії з максимальною енергією електронів до 490 МеВ. Рассчитаны спектры интенсивности и поляризации когерентного тормозного излучения для проектируемой установки ННЦ ХФТИ (проект SALO) для двух возможных каналов вывода электронного пучка из ускорителя с максимальными энергиями пучка 490 и 730 МэВ. Показано, что при определенных условиях формирования возможно получение пучков КТИ с интенсивностью и поляризацией, достаточными для проведения экспериментальных исследований в интервале энергий фотонов до 400 МэВ на пучковой линии с максимальной энергией электронов до 730 МэВ, и в интервале до 250 МэВ на пучковой линии с максимальной энергией электронов до 490 МэВ. The authors are thankful to Prof. P. Grabmayr for possibility to use his computer code for CB beam parameters calculation. This work is particulary supported by STCU project N3239. en Національний науковий центр «Харківський фізико-технічний інститут» НАН України Вопросы атомной науки и техники Теория и техника ускорения частиц The linearly polarized photon beam for photonuclear investigations at new NSC KIPT facility Лінійно поляризований фотонний пучок для фотоядерних досліджень на новому пристрої ННЦ ХФТІ Линейно поляризованный фотонный пучок для фотоядерных исследований на новой установке ННЦ ХФТИ Article published earlier |
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Digital Library of Periodicals of National Academy of Sciences of Ukraine |
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DSpace DC |
| title |
The linearly polarized photon beam for photonuclear investigations at new NSC KIPT facility |
| spellingShingle |
The linearly polarized photon beam for photonuclear investigations at new NSC KIPT facility Ganenko, V.B. Vashchenko, G.A. Burdeynyi, D.D. Теория и техника ускорения частиц |
| title_short |
The linearly polarized photon beam for photonuclear investigations at new NSC KIPT facility |
| title_full |
The linearly polarized photon beam for photonuclear investigations at new NSC KIPT facility |
| title_fullStr |
The linearly polarized photon beam for photonuclear investigations at new NSC KIPT facility |
| title_full_unstemmed |
The linearly polarized photon beam for photonuclear investigations at new NSC KIPT facility |
| title_sort |
linearly polarized photon beam for photonuclear investigations at new nsc kipt facility |
| author |
Ganenko, V.B. Vashchenko, G.A. Burdeynyi, D.D. |
| author_facet |
Ganenko, V.B. Vashchenko, G.A. Burdeynyi, D.D. |
| topic |
Теория и техника ускорения частиц |
| topic_facet |
Теория и техника ускорения частиц |
| publishDate |
2007 |
| language |
English |
| container_title |
Вопросы атомной науки и техники |
| publisher |
Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
| format |
Article |
| title_alt |
Лінійно поляризований фотонний пучок для фотоядерних досліджень на новому пристрої ННЦ ХФТІ Линейно поляризованный фотонный пучок для фотоядерных исследований на новой установке ННЦ ХФТИ |
| description |
Intensity and polarization spectrums of coherent bremsstrahlung for the designed facility NSC KIPT (project SALO) for two possible channels of output of electron beam from accelerator with the maximal energies of beam 490 and 730 MeV are calculated. It is shown, that at the definite conditions of forming the beam it is possible to obtain the CB beams with intensity and polarization, sufficient for conducting of experimental researches in the interval of energies of photons about 400MeV on the beam line with the maximal electron energy about 730 MeV , and in interval about 250 MeV on the beam line with the maximal electron energy about 490 MeV .
Розраховані спектри інтенсивності і поляризації когерентного гальмівного випромінювання для проектованої установки ННЦ ХФТІ (проект SALO) для двох можливих каналів виведення електронного пучка з прискорювача з максимальними енергіями пучка 490 і 730 МеВ. Показано, що за певних умов формування можливе отримання пучків КГВ з інтенсивністю і поляризацієй, достатніми для проведення експериментальних досліджень в інтервалі енергій фотонів до 400 МеВ на пучковій лінії з максимальною енергією електронів до 730 МеВ, і в інтервалі до 250 МеВ на пучковій лінії з максимальною енергією електронів до 490 МеВ.
Рассчитаны спектры интенсивности и поляризации когерентного тормозного излучения для проектируемой установки ННЦ ХФТИ (проект SALO) для двух возможных каналов вывода электронного пучка из ускорителя с максимальными энергиями пучка 490 и 730 МэВ. Показано, что при определенных условиях формирования возможно получение пучков КТИ с интенсивностью и поляризацией, достаточными для проведения экспериментальных исследований в интервале энергий фотонов до 400 МэВ на пучковой линии с максимальной энергией электронов до 730 МэВ, и в интервале до 250 МэВ на пучковой линии с максимальной энергией электронов до 490 МэВ.
|
| issn |
1562-6016 |
| url |
https://nasplib.isofts.kiev.ua/handle/123456789/110563 |
| citation_txt |
The linearly polarized photon beam for photonuclear investigations at new NSC KIPT facility / V.B. Ganenko, G.A. Vashchenko, D.D. Burdeynyi // Вопросы атомной науки и техники. — 2007. — № 5. — С. 160-165. — Бібліогр.: 12 назв. — англ. |
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| fulltext |
THE LINEARLY POLARIZED PHOTON BEAM
FOR PHOTONUCLEAR INVESTIGATIONS
AT NEW NSC KIPT FACILITY
V.B. Ganenko∗, G.A. Vashchenko, D.D. Burdeynyi
National Science Center ”Kharkov Institute of Physics and Technology”, 61108, Kharkov , Ukraine
(Received January 6, 2007)
Intensity and polarization spectrums of coherent bremsstrahlung for the designed facility NSC KIPT (project SALO)
for two possible channels of output of electron beam from accelerator with the maximal energies of beam 490 and
730 MeV are calculated. It is shown, that at the definite conditions of forming the beam it is possible to obtain
the CB beams with intensity and polarization, sufficient for conducting of experimental researches in the interval
of energies of photons about 400 MeV on the beam line with the maximal electron energy about 730 MeV , and in
interval about 250 MeV on the beam line with the maximal electron energy about 490 MeV .
PACS: 29.27.Hj
1. INTRODUCTION
At present and in foreseeable future fundamental
nuclear physic investigations will be of great impor-
tance both in low (from tens MeV) and high (up to
TeV) energy range from point of view of searching an-
swers on substantial questions of natural science, such
as the elementary particles structure, matter evolu-
tion, on one hand, and the possibility of practical ap-
plication of the fundamental investigation results, on
other hand [1]. To provide these investigations new
accelerator facilities are created, e.g. LHC and FIAR,
and operative facilities are constantly upgraded, e.g.
electron accelerators at intermediate energies MAMI
and Jlab.
The project of new accelerator facility (project
SALO) aimed on fundamental photonuclear investi-
gations in intermediate energy range is discussed in
NSC KIPT [2, 3]. The supposed accelerator param-
eters: maximal electron energy up to 730MeV , cur-
rent up to 100 mkA, duty cycle ∼ 100%, will provide
possibilities for production both polarized and unpo-
larized continues electron and photon beams that will
allow to perform high level experiments with electro-
magnetic probes in intermediate energy range. These
experiments could be aimed on studying fundamen-
tal problems, such as precision test and development
QCD approach in intermediate and low energy range,
e.g. ChPT, study hadron structure and it changes
in the nuclear matter, baryon mass spectrum, fun-
damental symmetries violation etc. These problems
decision require performing a wide experimental pro-
gram on studying single and pair pion photoproduc-
tion on nucleon and nuclei near threshold, Compton
scattering on nucleon and nuclei, η-nuclei photopro-
duction, electron scattering on nucleon and nuclei
[4, 5]. The experiments with polarized photon beam
will play very important part in such investigations
and one of the main requirements for them will be
high accuracy of the measurements.
Under SALO accelerator conditions the linearly
polarized photon beam could be produced on the base
of coherent bremsstrahlung radiation (CB) generated
by relativistic electrons in diamond crystal. The di-
amond crystal due to high Debye temperature, per-
fect crystal lattice and small atomic number provides
most high operating parameters (intensity and po-
larization) of the beam. As is known, in consequence
of periodicity of the atom location in the crystal lat-
tice, when relativistic electrons fall onto the crystal
at a small angle ψ relative to the crystal axes (but
exceeding substantially a critical angle of axial chan-
neling, ψ >> ψc) interference maxima appear in the
radiation spectra. The radiation intensity in these
maxima substantially exceeds the radiation intensity
in an amorphous material and in addition the radia-
tion in it has a significant linear polarization.
The spectrum and polarization of the CB are well
described by theory based on Born approximation.
According to [6, 7, 8] the CB cross section can be
represented as:
dσCB = dσin + dσcoh,
where dσcoh is the interference part of the CB cross
section depending on the crystal orientation relatively
to the electron beam; dσin is the non-coherent part
of the cross section, which does not depend on the
crystal orientation and represents itself a cross sec-
tion of usual bremsstrahlung in the amorphous sub-
stance. Thus, CB beam spectrum consists of two
parts: coherent part with interference maximum and
usual bremsstrahlung. The interference peak has a
∗Corresponding author. E-mail address: ganenko@kipt.kharkov.ua
160 PROBLEMS OF ATOMIC SCIENCE AND TECHNOLOGY, 2007, N5.
Series: Nuclear Physics Investigations (48), p.160-165.
sharp upper border and is reduced slowly in the low-
energy area. With increasing angle ψ the radiation
intensity in the peak falls, the peak itself is displaced
to higher energy range and at large ψ it is not ob-
served.
The CB beams were created practically at
every electron accelerators with beam energy of
E0 ∼ 1 GeV [9]. At present the CB beams are suc-
cessfully being used in Mainz [10] and at the Jeffer-
son Laboratory in USA [11]. As the polarized photon
beam is necessary for providing experimental photo-
nuclear program at NSC KIPT on the SALO facility
[5], we have studied a possibility of the linear polar-
ized photon beam creation on the base of CB elec-
trons in the diamond crystal and estimated expected
parameters of such beam.
2. RESULTS AND DISCUSSION
The SALO project facility lay out [2, 3] is shown
in Fig.1. The electron accelerator (superconduct-
ing recirculator) is placed in the existing room of
the LU − 2 GeV facility. The proposed accelerat-
ing structure will give growth energy rate 20 MeV/m
and provide increasing of the electron beam energy
on 240 MeV after each passing through it. The mag-
netic system will allow make only three passing the
beam through the accelerating structure so maximal
energy of the electron beam will reach 730 MeV , if
one will take into account exit energy from injector
(∼ 10 MeV ), along the lines to the experimental Hall
SP − 103 of the old linac LU − 2 GeV . There is an
intention to construct two beam lines in SP − 103
Hall, Fig 1: the first beam line for experiments with
real tagged photons (both unpolarized and linearly
and circularly polarized) in the energy range up to
730 MeV (High Energy Photon Line-Line A); the sec-
ond beam line for experiments with electrons with the
same maximal energy (Electron Beam Line-Line C).
The third beam line is proposed to be constructed in
the Lens Hall of the linac LU−2 GeV and it is aimed
on experiments with real tagged photons (also both
unpolarized and linearly and circularly polarized) in
low energy range, up to 490 MeV (Low Energy Pho-
ton Line-Line B). The linearly polarized photon beam
on both photon beam lines is planned to obtain using
the CB process of the electrons in diamond crystals.
Fig.1. General scheme of the SALO facility with beam lines. A-High Energy Photon Line, B-Low Energy
Photon Line, C-Electron Beam Line, D-Free Electron Laser Line
For estimation of the possible CB beam param-
eters, intensity and polarization and their depen-
dence on crystal orientation for proposed photon
beam lines the relevant calculations were made with
using analytical code developed by P.Grabmayr and
co-workers [12] on the base of Born approximation
[6, 7, 8]. At present this is the most perfect pro-
gram for the CB characteristics calculation which al-
low to take into account most of experimental fac-
tors with sufficient accuracy: electron beam size, en-
ergy and angular divergence, multiple scattering in
the crystal, photon beam collimation. In compar-
ison with previous calculations some improvements
were made in this program both in the CB for-
mula [7] and in procedure of the experimental fac-
tors taking into account. Improvements in the for-
mula included new parameterizations of the carbon
form factor, the angular distributions of the coher-
ent and incoherent electron-nuclear contributions and
the electron-electron bremsstrahlung. For the exper-
imental factors taking into account the following as-
sumption were made. The beam angular distribu-
tion and electron beam distribution function due to
multiple Coulomb scattering were assumed to be of
two-dimensional Gaussian shape. The electron beam
distribution within spot on the target and electron
beam energy spread around the nominal energy E0
were also approximated by Gaussians. With such ap-
proach the expected calculated the CB intensity re-
sults from folding of all experimental effects weighted
with the above distributions and as a result the 8-fold
integral was appeared.
For calculation this 8-fold integral a Monte Carlo
method was used but it takes sufficiently much
time. For acceleration the CB calculation an ana-
lytical approach was developed in which: (i) all two-
dimensional distributions were assumed to be Gaus-
sian in shape with azimuthal symmetry; (ii) the over-
161
all electron angular distribution was obtained by fold-
ing the electron beam multiple scattering and initial
angular divergence distributions; (iii) for the colli-
mated photon spectra calculation the effects of the
beam size, divergence and multiple scattering were
also combined into one Gaussian angular distribution
with relevant parameters. This code was tested and
well described the CB beam parameters obtained at
the Mainz facility for E0 = 855 MeV . A comparison
of the analytical and Monte Carlo codes calculations
has shown that they gave almost identical results.
Using analytical code [12] we made calculations of
the CB beam spectra and polarization for diamond
crystal with thickness 0.1 mm. The crystal orienta-
tion is determined by two angles, θ and α. θ is the an-
gle between electron beam momentum P0 and crystal
axis b1 = 〈100〉,α is the angle between planes (P0, b1)
and planes (b1, b2), where b2 = 〈010〉. The angles θ
and α were chosen in a such a way that main con-
tribution to the CB cross section was produced point
(0, 2, 2̄) of the crystal reciprocal lattice. The electron
beam energy spread was assumed to be 0.08%, di-
ameter of the electron beam spot on the target was
1 mm.
Some calculation results are shown in
Fig.2,3 where the polarization P, total intensity
Isum = Icoh + Iin, and coherent effect β of the CB
are presented. Coherent effect is determined by the
relation
β =
Icoh + Iin
Icoh
,
Icoh and Iin are the intensity of the ra-
diation per one electron and is deter-
mined as Icoh,in = (Eγ/σ0)(dσcoh,in/dEγ), where
σ0 = 0.5794 · 10−27 Z2cm2. In Fig.3 it is shown
calculations for initial electron energy E0 = 730
and 490 MeV and collimation angles in the inter-
val from θc ≈ 0.5 θγ and up to 1.9 θγ (θγ = mc2/E0,
where m is the electron mass). The orientation an-
gle’s values were chosen so that energy of the CB
peak was Ep
γ = 170.5 MeV (relative photon energy
X = Eγ/E0 = 0.23), but due to multiple scatter-
ing of the electron beam the real peak position is
shifted to slightly lower energy. One can see that at
these conditions for beam Line A at relative energy
X ∼ 0.2, we may obtain essentially high polariza-
tion (Pγ ∼ 55%) at the CB peak and coherent effect
β ∼ 2.5− 3 even without any collimation of the pho-
ton beam. At the strong collimation (θc ≈ 0.47) the
polarization is increased up to ∼ 75% and coherent
effect become two times more but the total intensity
in the CB maximum becomes six times less.
0 100 200 300 400 500 600 700
0
3
6
9
12
1
2
3
4
5
P
-0,2
0,0
0,2
0,4
0,6
0,8
E , MeV
Isum
E
0
=730 MeV
0 100 200 300 400 500 600 700
0
5
10
15
20
25
30
35
1,0
1,5
2,0
2,5
3,0
E , MeV
P
Isum
-0,1
0,0
0,1
0,2
0,3
0,4
0,5
0,6
0,7
E
0
=730MeV
Fig.2. Polarization, coherent effect and full intensity of the CB for collimation angles:
left panel - θc = 0.47 θγ (solid line,) and 0.71 θγ (dashed line);
right panel - θc = 1.19 θγ (solid line) and 1.9 θγ (dashed line)
Calculations for more high peak energies
X ∼ 0.41 are presented in Fig. 3 for E0 = 730 and
490 MeV and some collimation angles in interval
from θc ∼ 0.5 and up to θc ∼ θγ . We can see that for
E0 = 730 MeV polarization and coherent effect are
changed in the range P ∼ 0.4−0.6 and β ∼ 2−3 and
they are P ∼ 0.35 and β ∼ 1.7 for E0 = 490 MeV .
From previous experience it is known that the CB
162
beam can be used in experiments if the polarization
and coherent effect are no less than Pγ ∼ 30% and
β ∼ 1.5, so the CB beam parameters for this photon
energy are also good enough for using in polarized
experiments.
0 100 200 300 400 500 600 700
0
2
4
6
8
10
12
1,0
1,5
2,0
2,5
3,0
3,5
E , MeV
P
Isum
-0,2
-0,1
0,0
0,1
0,2
0,3
0,4
0,5
0,6
0,7 E
0
=730 MeV
=0,0607
=0,5749
100 200 300 400 500
0
2
4
6
8
10
12
14
E , MeV
P
Isum
1,0
1,2
1,4
1,6
1,8
-0,1
0,0
0,1
0,2
0,3
0,4 E
0
=490 MeV
=0,08
=0,54
Fig.3. Polarization, coherent effect and full intensity of the CB.
Left panel: initial electron energy E0 = 730 MeV , collimation angles θc = 0.47 θγ (solid line), 0.95 θγ
(dashed line);
right panel: E0 = 490 MeV , θc = 0.63 θγ (solid line) and 1.12 θγ (dashed line)
In more detail the CB parameters collimation de-
pendence for is shown on Fig.4 for initial electron
energies E0 = 730 MeV and 490 MeV and the CB
peak energy X ≈ 0.23. It demonstrates fast increas-
ing of the polarization and coherent effect values
with decreasing collimation angle, especially for an-
gles θc ≤ 0.8 θγ where these parameters can reach val-
ues P ∼ 80% and β ∼ 5− 6 for strong photon colli-
mation. On other hand polarization and coherent ef-
fect do not practically change for collimation angles
θc > 0.8 θγ , and at the same time the CB intensity
is somewhat increased with the collimation angle in-
creasing. So it is more preferable to use more collima-
tions angle if there are no any additional restrictions.
0,2 0,4 0,6 0,8 1,0 1,2 1,4 1,6 1,8 2,0
0,0
0,5
1,0
1,5
2,0
2,5
3,0
3,5
4,0
4,5
5,0
5,5
6,0 E
0
=730 MeV
E
0
=490 MeV
U
c
0,2 0,4 0,6 0,8 1,0 1,2 1,4 1,6 1,8 2,0
0,0
0,1
0,2
0,3
0,4
0,5
0,6
0,7
0,8
0,9
1,0
E
0
=730 MeV
E
0
=490 MeV
P
U
c
Fig.4. Coherent effect and polarization dependencies from collimation angle for initial electron energy
E0 = 730 MeV and peak photon energy 170 MeV and for initial electron energy
E0 = 490 MeV and peak photon energy 100 MeV
163
The important characteristic of the polarized
beam is the energy range where the beam could be
applied for photonuclear investigations. In Fig.5 it is
presented the results of the energy dependence cal-
culations of the coherent effect and polarization for
electron beam energies E0 = 490 MeV and 730 MeV ,
which will be acceptable on SALO photon beam lines.
It is seen that the values of the coherent effect and
polarization decrease from β ≈ 3.6 and Pγ ≈ 70%
at Eγ ∼ 100 MeV up to β ≈ 1.6 and Pγ ≈ 25% at
Eγ ∼ 400 MeV for initial electron energy 730 MeV
and from β ≈ 2.8 and Pγ ≈ 60% at Eγ ∼ 50 MeV and
up to β ≈ 1.5 and Pγ ≈ 23% at Eγ ≈ 250 MeV for
initial electron energy E0 = 490 MeV . The calcula-
tions demonstrate that acceptable energy ranges for
nuclear physic investigation with linearly polarized
photons for Line A is extended up to photon energy
Eγ ∼ 400 MeV at collimation θc ∼ θγ and could be
increased up to 450 MeV under more strong collima-
tion. That will allow one to study pair pion photo-
production on nucleon and nuclei near threshold with
polarized photons. The acceptable interval for Line
B, where experiments with polarized photon are also
planned, is extended up to Eγ ≈ 250 MeV that is it
enough to cover the experiments on single pion pho-
toproduction at threshold energy range.
0 50 100 150 200 250 300 350 400
0,0
0,5
1,0
1,5
2,0
2,5
3,0
3,5
4,0
E , MeV
E
0
=730 MeV
E
0
=490 MeV
50 100 150 200 250 300 350 400
0,0
0,1
0,2
0,3
0,4
0,5
0,6
0,7
0,8
0,9
1,0
E , MeV
E
0
=730 MeV
E
0
=490 MeV
P
Fig.5. Coherent effect and polarization dependencies from peak energy for initial electron energy
E0 = 730 MeV and collimation angle θc = 0.95 θγ , and E0 = 490 MeV and collimation angle θc = 0.63 θγ
The authors are thankful to Prof. P. Grabmayr
for possibility to use his computer code for CB beam
parameters calculation. This work is particulary sup-
ported by STCU project N3239.
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ЛИНЕЙНО ПОЛЯРИЗОВАННЫЙ ФОТОННЫЙ ПУЧОК ДЛЯ ФОТОЯДЕРНЫХ
ИССЛЕДОВАНИЙ НА НОВОЙ УСТАНОВКЕ ННЦ ХФТИ
В.Б. Ганенко, Г.А. Ващенко, Д.Д. Бурдейный
Рассчитаны спектры интенсивности и поляризации когерентного тормозного излучения для проек-
тируемой установки ННЦ ХФТИ (проект SALO) для двух возможных каналов вывода электронного
пучка из ускорителя с максимальными энергиями пучка 490 и 730 МэВ. Показано, что при опре-
деленных условиях формирования возможно получение пучков КТИ с интенсивностью и поляриза-
цией, достаточными для проведения экспериментальных исследований в интервале энергий фотонов
до 400 МэВ на пучковой линии с максимальной энергией электронов до 730 МэВ, и в интервале до
250 МэВ на пучковой линии с максимальной энергией электронов до 490 МэВ.
ЛIНIЙНО ПОЛЯРИЗОВАНИЙ ФОТОННИЙ ПУЧОК ДЛЯ ФОТОЯДЕРНИХ
ДОСЛIДЖЕНЬ НА НОВОМУ ПРИСТРОЇ ННЦ ХФТI
В.Б. Ганенко, Г.А. Ващенко, Д.Д. Бурдейний
Розрахованi спектри iнтенсивностi i поляризацiї когерентного гальмiвного випромiнювання для про-
ектованої установки ННЦ ХФТI (проект SALO) для двох можливих каналiв виведення електронного
пучка з прискорювача з максимальними енергiями пучка 490 i 730 МеВ. Показано, що за певних умов
формування можливе отримання пучкiв КГВ з iнтенсивнiстю i поляризацiєю, достатнiми для про-
ведення експериментальних дослiджень в iнтервалi енергiй фотонiв до 400 МеВ на пучковiй лiнiї з
максимальною енергiєю електронiв до 730МеВ, i в iнтервалi до 250 МеВ на пучковiй лiнiї з макси-
мальною енергiєю електронiв до 490 МеВ.
165
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