SOVIET ATOMIC ENERGY VOLUME 21, NUMBER 5

• Document Type: CREST
• Collection: General CIA Records
• Document Number (FOIA) /ESDN (CREST): CIA-RDP10-02196R000700040005-9
• Release Decision: RIFPUB
• Original Classification: K
• Document Page Count: 117
• Document Creation Date: December 23, 2016
• Document Release Date: March 12, 2013
• Sequence Number: 5
• Publication Date: November 1, 1966
• Content Type: REPORT

Declassified and Approved For Release 2013/03/12 CIA-RDP10-02196R000700040005-9
um er5
SOVIET
ATOMIC
ENERGY
ATOMHAR 3HEPGI4R
(ATOMNAYA ENERGIYA)
TRANSLATED FROM RUSSIAN
CONSULTANTS' BUREAU
Declassified and Approved For Release 2013/03/12 : CIA-RDP10-02196R000700040005-9
 Declassified and Approved For Release 2013/03/12 : CIA-RDP10-02196R000700040005-9
SOVIET
ATOMIC
ENERGY
Soviet Atomic-Energy is a cover-to-cover` translation of Atomnaya
Energiya, a publication of the Academy: of Sciences of the USSR:
An arrangement- with Mezhdunarodnaya Kniga, the Soviet book
export agency, makes available, both advance copies of the Rus-
sian journal and original glossy photographs and artwork.'This'
serves to. decrease the necessary time lag between publication
of the original and publication of the translation and helps to im-
prove the quality,of the.latter. The translation began with the first
issue of the. Russian journal. 4
Editorial Board of Atomnaya Energiya:
Editor: M. D. Millionshchikov
Deputy Director, institute of Atomic Energy
imeni I. V. Kurchatov
Academy of Sciences of the USSR,_
Moscow, USSR
Associate Editors: N. A. Kolokol'tsov
N. A. Vlasov
A.'l. Alikhanov
A. A. B.ochvar
N. A. Dollezhal'
V.S. Fursov
N. Golovin,\
V. F. Kalinin
A. K. Krasin
A. 1. Leipunskii,
V. V. Matveev
M. G. Meshcheryakov
P. N. ;Pa1ei
V. B. Sherchenko
D. L. Simonenko
V. I. Smirnov
A. P. Vinogradov
A. P. Zefirov
Copyright ? 1967 Consultants Bureau, a division of Plenum Publishing Corpora-
tion, 227.West 17th Street, New York, N. Y. 16011. All rights reserved. No article
contained herein may_ be, reproduced for eny purpose whatsoever without per-
mission of the publishers. '
Subscription Single Issue: $30
'02 Issues): $95 Single Article: $15
Order from:
6
lJ
CONSULTANTS BUREAU.
227- West 17th Street,`- New- York,- New York 10011
Declassified and Approved For Release 2013/03/12 : CIA-RDP10-02196R000700040005-9
 Declassified and Approved For Release 2013/03/12 : CIA-RDP10-02196R000700040005-9
SOVIET ATOMIC ENERGY
A translation of Atomnaya Energiya
Volume 21, Number 5 November, 1966
CONTENTS
Interaction of Fast Hi Ions with Metal Surfaces in Very High Vacuum - E. S. Borovik,
N. P. Katrich, and G. T. Nikolaev ...........................................
Method of Calculating the Intensity of Back-Scattered y-Radiation - B. P. Bulatov ... .
Limiting Current Density in a Linear Ion Accelerator - A. V. Zotov and V. A. Teplyakov
Use of the Calculated-Expense Method for Choosing The Characteristics of a Fast
Reactor - V. B. Lytkin, M. F. Troyanov, and A. I. Novozhilov .................
IR-100 Research and Training Reactor - Yu. M. Bulkhin, A. D. Zhirnov, G. N. Zhemchuzh-
nikov, L. V. Konstantinov, V. A. Nikolaev, I. A. Stenbok, V. S. Lobanov, N. A.
Khryastov, and A. G. Filippov ...............................................
Evaporation Rates of Cathodes Made of Uranium Carbide, Zirconium Carbide, and
their Solid Solutions - B. S. Kul'varskaya ....................................
Formation of Polymer Products in the Radiolysis of Mixtures of Hexafluorobenzene
with Perfluorocyclohexane ands Perfluorononane - V. A. Khramchenkov .........
Changes in the Properties of Ion Exchangers After Prolonged Use in the Purification
of Radioactive Waste Water - F. V. Rauzen and Z. Ya. Solov'eva ...............
ABSTRACTS,
Propagation of Capture y-Radiation in a Uniform Spherical Shield - B. K. Fedyushin ...
Approximate Solution of the Dynamic Equations of a Nuclear Reactor - N. G. Chelintsev
Solution of the Diffusion Equation in Periodic Lattices in Terms of Trigonometric Series
- G. Ya. Rumyantsev .......................................................
A Very Simple Mathematical Model for Studying the Dynamics of Self-Regulating Water-
Cooled Water-Moderated Reactors - F. M. Mitenkov, B. I. Motorov, and E. A.
Motorova ......................... .....................................
Improved System of Stationary Dosimetric Monitoring at the VVR-M Reactor - E. A.
Konovalov, L. M. Ploshchanskii, and V. A. Solov'ev ..........................
Calculation of the Absorption of Epithermal Neutrons in an Infinite Lattice of Absorbing
Slabs - V.N. Gurin ........................................................
LETTERS TO THE EDITOR
Possibilities of the Photoneutron Method for Determining Hydrogen in Heavy Metals -
N. P. Mazyukevich and V. A.Shkoda-Ul'yanov ................................
Calculating Photoelectric Attenuation Coefficients for Gamma Radiation - O. S.
Marenkov ...... ............................. ?........................
Neutron Yield Curve for a Tritium Target - L. N. Katsaurov and A. N. Kuznetsov .. .
Angular Distribution of Fast Neutrons Emerging from a Medium which Contains
Hydrogen - S. F. Degtyarev, V. I. Kukhtevich, A. P. Suvorov, V. V. Tarasov,
V. K. Tikhonov, and S. G. Tsypin ...........................................
Engl./Russ.
1019 339
1026 345
1034 356
1042 363
1047 368
1054 375
1058 378
1062 382
1064 383
1065 385
1067 386
1068 386
1071 389
1073 390
Declassified and Approved For Release 2013/03/12 : CIA-RDP10-02196R000700040005-9
 Declassified and Approved For Release 2013/03/12 : CIA-RDP10-02196R000700040005-9
CONTENTS
Engl./Russ.
Passage of Fast Neutrons Through Thick Layers of Lithium Hydride - G. M. Bozin, S. F.
Degtyarev' V. I. Kukhtevich, B. I. Sinitsyn, V. B. Staroverov, V. K. Tikhonov, and
S. G. Tsypin ............................................................... 1079 394
Build-up Factor of Fast Neutrons Versus the Relative Positions of Shielding and
Detector - S. F. Degtyarev, V. I. Kukhtevich, V. K. Tikhonov, and S. G. Tsypin ... 1081 395
Passage of Gamma Rays Through Spherical and Cylindrical Shielding Barriers -
A. V. Larichev, O. F. Partolin, E. D. Chistov, and O. M. Zaraev ............... 1084 398
Yields of Nuclear Reactions for Making Na22 in a Cyclotron - N. N. Krasnov and P. P.
Dmitriev .................................................................. 1087 400
Effect of Accelerating Voltage on Intensity in the Dubna Synchrocyclotron - V. L Danilov,
I. B. Enchevich, E. A. Polferov, and A. N. Safonov ............................. 1089 402
Determination of Accelerator Perturbations from Information on Particle Loss Distribution
- I. P. Karabekov ........................................................... 1092 404
Effective Method of Performing Multigroup Reactor Calculations - V. V. Khromov and
A. M. Kuz'min .............................................................. 1095 406
Calculating the Doppler Temperature Coefficient of Reactivity for Homogeneous Reactors
- F. M. Mitenkov, B. A. Averbakh, L. M. Gorbunov, and O. B. Samoilov ......... 1098 408
Effectiveness of a System of Control Rods Distributed Through a Reactor Core and
Reflector - V. I. Nosov ........... ........................................ 1101 410
Semiconductor (Germanium) y-Ray Spectrometer Determines Burnup in Fuel Elements -
L. V. Groshev, A. M. Demidov, G. A. Kotel'nikov, and O. A. Miller . . . .......... 1104 412
Fluorite Activation, Analysis Assay in Ore Samples and in Ore Beneficiation Products -
V. I. Prokopchik and T. I.Subbotina .......................................... . 1108 415
Vapor-Phase Chromatographic Separation and Gamma-Ray Spectrometric Analysis of
Gaseous Effluents of the VVR-M Reactor - V. A. Solovtev, O. V. Stepanets, and
V. D. Trenin ............................................................... 1110 417
NEWS OF SCIENCE AND TECHNOLOGY
[Conference of Experts on Microbiological Problems in Irradiation Preservation of
Foodstuffs - N. N. Mazokhina ............................................... 419]
All-Union Conference on' Phase Diagrams of Metallic Systems - I. A. Markova .......... 1113 420
Poviet Delegation Visits Canada - E. Kulish ........................................ 422]
[Nucleonic Instrumentation at the British Industrial Exhibit in Moscow - Yu. K. ......... , 425]
BRIEF COMMUNICATIONS
[Third International Congress on Radiation Research ................................. 426]
15oviet Scientists Visit Radiobiological Centers in the USA ............................ 426]
British Scientists Visit the USSR ...........................:....... .............. 1116 426
BOOK REVIEWS
K. Rohrdanz - Nuclear Engineering-in a Nutshell ........................... ....... 1117 427
Proceedings of the Third International Conference on the Peaceful Uses of Atomic
Energy. Vol.2. Reactor Physics = Reviewed by Yu. I. Mityaev ................... 1117 427
A. B. Clegg - High Energy Nuclear Reactions .......... .......... 1118 427
D. C. Layman and G. Thornton - Remote Handling of Mobile Nuclear Systems - Reviewed
by M. Orlov ................................................................ 1119 427
Criticality Control of Fissile Materials - Reviewed by Yu. K . ........ . ............... 1120 428
Radioisotope Instruments in Industry and Geophysics - Reviewed by L. P . ............. 1120 428
Radioisotope Sample Measurement Techniques in Medicine and Biology - Reviewed by
Yu. V. Sivintsev .................... .......... ........................ ....... 1122 430
Declassified and Approved For Release 2013/03/12 : CIA-RDP10-02196R000700040005-9
 Declassified and Approved For Release 2013/03/12 : CIA-RDP10-02196R000700040005-9
CONTENTS
Engl./Russ.
Radioisotopes in Endocrinology. First Anniversary of the Society for Nuclear Medicine
in Freiburg im Breisgau, October 17-19, October 1963 ....................... 1124 431
Dosimetry of Ionizing Radiations (Basic Concepts and their Terminology) USSR Academy
of Sciences, Committee on Scientific and Technical Terminology. Collections of
Recommended Terms. No.70 ... . . . . . . .... . . . 1124 431
J. S. Strettan - Ionizing Radiations 1125 431
G. W. Reed - Proceedings of the International "Enrico Fermi" School of Physics
Course XXX - Radiation Dosimetry - Reviewed by Yu. V. Sivintsev ............ 1125 431
E. I. Vorobtev et al. Radiobiology and Clinical Radiology. Proceedings of the Central
X-Ray and Radiological Scientific Research Institute. Volume V ............... 1126 432
Rules and Regulations for Safe Transportation of Radioactive Materials. Revised 1964
Edition. No.6 in Series on Safety ............................................ 1127 432
ERRATA ....... ............................................. 1128
The Table of Contents lists all material that appeared in the original Russian journal. Items origi-
nally published in English or generally available in the West are not included in the translation and
are shown in brackets. Whenever possible, the English-language source containing the omitted items
is given.
The Russian press date (podpisano k pechati) of this issue was 10/29/1966.
Publication therefore did not occur prior to this date, but must be assumed
to have taken place reasonably soon thereafter.
Declassified and Approved For Release 2013/03/12 : CIA-RDP10-02196R000700040005-9
 Declassified and Approved For Release 2013/03/12 : CIA-RDP10-02196R000700040005-9
INTERACTION: OF FAST H1+ IONS WITH METAL
E.S. Borovik, N.P. Katrich, UDC 532.6:533.9
and G.T. Nikolaev
'The results of experiments on the interaction of fast hydrogen ions (H1+) with
metals, forming weak chemical bonds (nickel, stainless steel) and metals form-
ing strong chemical bonds (tantalum and titanium) with hydrogen are presented.
The weighing method was used under very-high vacuum conditions to determine
the sputtering coefficient cz of stainless steel bombarded by 35-keV Hi ions and
the penetration coefficient 77 of Hi ions entering the stainless steel (a = 9.10-3,
17 = 0.5 for hydrogen concentrations greatly exceeding 1019 atoms /cm2), The
variation of 77 with the density of the hydrogen introduced and the temperature of
the metals was determined by the pressure-variation method. The results indi-
cate that metals of the titanium type are suitable for use in capturing fast hydro-
gen atoms in magnetic traps.
The collision of fast particles with metal surfaces is accompanied by three main processes: the
desorption of adsorbed gases, the atomization or sputtering of the metals, and the penetration of fast
particles into the metals. In magnetic traps, the desorption of adsorbed gases and the sputtering of the
metals leads to contamination of, the plasma, while the penetration of the fast particles has a favorable
influence, since under certain conditions this may lighten the burden of the pumping system.
Many papers have been written on the sputtering of metals, but so far no one has measured the
sputtering coefficient of metals under very-high vacuum conditions.
The penetration of hydrogen ions Hi and Di was studied in [1, 2], but the results were not in
agreement. The -difference was as follows. The penetration coefficient of D1 ions found in [1] was 0.2
to 0.35 for incident particles of energy 7 to 25 keV, For a concentration of 3.1017 hydrogen atoms/cm2
in stainless steel, saturation set in, this being defined by the authors as the condition in which the flows
of hydrogen into and out of the target were equal. The penetration coefficient of Hi ions obtained in [2]
was 0.9, no saturation being observed up to a concentration of 2.1019 cm-2,
Since the number of hydrogen atoms introduced into the metal may exceed 1019 (according to [2]),
there is a distinct possibility of determining the penetration factor gravimetrically. We employed this
method to measure the sputtering coefficient a of stainless steel bombarded by 35-keV Hi ions and the
penetration coefficient 77 of the Hi ions into the steel; we also studied the variation of the penetration
coefficient of Hi ions into titanium, tantalum, nickel, and stainless steel with the temperature of the
target bombarded and the density of the hydrogen thus introduced.
DETERMINATION OF a AND 77 GRAVIMETRICALLY
The apparatus on which our experiments were conducted consisted of a system of hydrogen and
helium condensation pumps (HCP and HeCP respectively), a high-frequency ion source, and a measuring
chamber. The heated measuring chamber was assembled with copper gaskets. A detailed description
of the apparatus is given in [2].
Figure 1 shows the arrangement of the measuring chamber. The chamber was degassed by heating
to approximately 600?C for 3 h. The stainless steel target, 1.5 g in weight, already mechanically
polished, was washed in gasoline, then in alcohol, and fixed in the holder 1. The target holder was in-
sulated from the measuring chamber by means of a glass junction, which enabled the ion current to be
Translated from Atomnaya Energiya, Vol. 21, No, 5, pp. 339-345, November, 1966. Original
article submitted May 1, 1966.
Declassified and Approved For Release 2013/03/12 : CIA-RDP10-02196R000700040005-9
 Declassified and Approved For Release 2013/03/12 : CIA-RDP10-02196R000700040005-9
Fig. 1. Arrangement
of measuring cham-.
her: 1) target holder;
2) target; 3), 7) hydro-
gen condensation
pumps; 4) screen; 5)
collector; 6) metal
valve.
v7%t
3.8.1019
?2.10-9
+3.10-5
1.85.1019
0.49 9.10-3
2.1 ? 1019
2.10-6
7-1,6.10-5
4.1016
0.48 8.5?'10-3
;,4.101^
1.10-6
+2.7.10-s
1..7.1019
0.5 9.10-3
Note: No is the number of ions striking the target; N 1 is the number of ions
entering into the target.
10152 46810f62 4681072 46810182 468fOf.
IV, atoms/cm2
Fig. 2. Variation of t with the density
of the hydrogen penetrating into stain-
less steel.
measured directly during the bombardment of the target. The target was heated to about 600?K at the
same time as the measuring chamber. The aluminum-foil collector 5 was protected'from the scattered
ion beam by screen 4 and heated to about 500?K by thermal radiation from the chamber walls. The weight
of the collector was - 0.5 g. Evacuation of the measuring chamber during the degassing_ period was eff-
ected by HCP-2. At the conclusion of the heating period the vacuum reached -1.10-7 mm Hg. After
heating, liquid helium was poured into the HeCP and liquid hydrogen into HCP-1; then the measuring
chamber was disconnected from HCP-2 by means of the heated metal valve 6. In this way the vacuum
in the measuring chamber was brought up to 5.10-10mm Hg.
The 35-keV Hi ion beam was recorded electrically, using the cutoff potential applied to the collector
5. The ion-beam current was usually 100 to 150 p A. The sputtered target metal was collected by the
collector.
The target and collector were weighed on,microanalytical balances. Experiments showed that as a
result of the first heating to 600?K in a vacuum of 1.1077mm Hg, the weight of a freshly prepared target
fell very slightly. The weight of the collector fell rather, more, apparently because of its greater surface
area. On subsequent heating, the weight of the target and collector remained constant (within weighing
accuracy): ? 1.10-6g for the target and ? 3.10-6g for the collector. No effect of atmospheric moisture
was noticed (within weighing accuracy); the weight of the target and collector remained constant for much.
longer than was needed for repeated weighing.
The values of a and q were calculated from the formulas
APc
9,3.10-3 a t
4Pc + Apt,
1,67.10-24 t
q
where Ape is the change in the weight of the collector in g, Opt is the change in the weight of the target
in g, i is the ion beam current in A, q is the charge on an electron in C, t is the time of target bombard-
ment in sec, 9.3.10-23g is the weight of an iron atom, and 1.67'10-24g is that of a hydrogen atom.
The measured values of a and i are shown in Table le
Declassified and Approved For Release 2013/03/12 : CIA-RDP10-02196R000700040005-9
 Declassified and Approved For Release 2013/03/12 : CIA-RDP10-02196R000700040005-9
We see from the table that the over-all change in weight is an order greater than the measuring
error. The gravimetrically obtained sputtering coefficient of stainless steel due to 35-keV H1 ions equals
9.10-3, while 11 equals 0.5, much smaller than the penetration coefficient found in [2].
In calculating a and 77, the absorption of residual gases by the sputtered metal and the desorption
of gases from the-target due to ion bombardment were not considered. As regards the absorption of
background gases by the sputtered metal, for gas pressures of -5.10-10mm Hg this is not very important.
In order to determine the quantity of gas desorbed from the target during bombardment, we made some
additional experiments. The method was as follows. The gas desorbed from the target by the H1 ions
was adsorbed on the surface of the HCP. Since the pumping rate of the HCP for the residual gases was
100 times that of the HeCP operating through a hole in the target chamber, we may consider that nearly
all the residual gases were pumped out by the HCP. After the elapse of a certain period of target bombard-
ment, the liquid hydrogen was taken from the HCP 3 and the bombardment was stopped at the same. time.
Since each gas had its own desorption temperature, on heating the HCP-1 the vacuum in the target chamber
varied in accordance with the quantity and type of the desorbed gas. The total quantity of heavy gases
desorbed from the target equalled 1 to 1.5 cm3 -mm Hg, which could not seriously affect the value of 77.
Thus the results of the weighing showed that the sputtering coefficient of stainless steel correspond-
ing to 35-keV H1 ions equalled 9.10-3, and the penetration coefficient of the same ions passing into the
steel was 0.5. Although this value is quite high, it is much smaller than that given by the varying-press-
ure method in [2]. The density of the hydrogen penetrating into the stainless steel (found gravimetricallyl
was much greater than 1019 atoms/cm2, which agrees closely with the results of the varying-pressure
method.
Attempts to match the gravimetric data on t with the data obtained in [2] by allowing for'the desor-
ption of gases from the target during bombardment were unsuccessful. In later investigations, which
will be published in a separate paper, it was found that the hydrogen in the target chamber was mainly
in the molecular state, not in the atomic state, as indicated in [2]. Allowing for this fact alters the
computing formula, doubling the quantity of nonpenetrating hydrogen, and giving a value of -0.8 for 71.
This is clearly insufficient to make the results agree. We therefore considered that an error might have
been made in calibrating the Bayard-Alpert ionization manometer (which was based on the LM-2 type).
This question is considered later.
MEASURING 77 BY THE VARYING-PRESSURE METHOD
As indicated earlier, in measuring the value of 77 by the method of varying pressure, a mistake was
made in the calculation, owing to the fact that the hydrogen evolved from the target during bombardment
was in the molecular and not the atomic state as indicated in [2]. Accordingly the computing formula for
the penetration coefficient will have the form
~1=1 2n(p-po)w (3)
760i/q
-10'52 4 6810f62 4 6810'2 4 681082 4 6810'
N, atoms/cm2
Fig. 3. Variation of 77 with the density
of the hydrogen penetrating into nickel.
Fig.4. Variation of 77 with the density
of the hydrogen penetrating into tita-
nium.
Declassified and Approved For Release 2013/03/12 : CIA-RDP10-02196R000700040005-9
 Declassified and Approved For Release 2013/03/12 : CIA-RDP10-02196R000700040005-9
where n is the number of H2 molecules in 1 dm3 under normal conditions, po is the initial pressure in
mm Hg, p is the working pressure in mm Hg, w is the rate of pumping hydrogen from the chamber in
dm3/sec, i is the Hi ion-beam current in A, q is the charge of an electron in C, and 760 mm Hg is at-
mospheric pressure. The factor of 2 accounts for the evolution of H2 from the target.
In order to investigate the possible error in determining the pressures po and p, we measured the
penetration- coefficients by-using a standard IM-12F ionization manometer specially intended for measur-
ing pressures in heated systems. Since the sensitivity of the ionization manometers was only half as
good for hydrogen as for nitrogen [4], the readings of the IM-12F manometer were adjusted accordingly.
For large concentrations of hydrogen in the metal (> 1019 atoms/cm2), the value of ri calculated from
formula (3) agreed with the penetration coefficient determined gravimetrically. i. e., with 0.5 and not
0.9. The variation of n with the concentration of hydrogen penetrating into the metal is shown in Fig. 2
(curve 2). In addition to this, we made some experiments to verify the characteristics of the ionization
manometer used in [2]. This manometer was based on a standard LM-2 ionization manometer intended
for measuring pressures in the range 10_3 to 5.10-8 mm Hg. The initial sensitivity of this instrument
was half that of the LM-2, and the linear range of the characteristic, recalculated in accordance with
the sensitivity and the fall in the photocurrent to the collector, was 5.10-10mm Hg. On comparing the
characteristics of this manometer with those of the standard IM-12F and LM-2 ionization manometers,
it was found that its sensitivity was three times worse than that determined earlier, and the linear range
of the characteristic lay in a narrower range of measured pressures.
The results of [2], recalculated to incorporate corrections for sensitivity and the nonlinearity of
the characteristic of the ionization manometer in the high-vacuum region, are shown in Fig. 2 (curve 1).
We see that the recalculated results agree quite well with those based on the IM-12F (see curve 2).
Since the quantity of hydrogen not penetrating into the metal increases with falling 71, the correction for
the evacuation of hydrogen by the HCP for concentrations >4.1017 cm-2 diminishes considerably. Taken
together with the nonlinearity of the ionization-manometer characteristic under high vacuum, this ex-
plains the disproportionate fall in the 71/N (cm-2) curve after recalculation in the regions of small and
large hydrogen concentrations.
Later it proved possible almost entirely to avoid the necessity of allowing for the rate of hydrogen
evacuation by the HCP. The measuring procedure reduced to the following. Immediately after beginning
the measurements, the H1 ion beam was defocused, and the HCP was saturated on account of the hydrogen
dissipated in the chamber, the area of the pumping surface of the pump being considerably reduced.
A knowledge of the temperature dependence of the capture and retention of fast hydrogen ions may
provide useful information on the state of hydrogen in metals, which is of interest in connection with a
number of applications.
We studied the variation of 71 with the density of the hydrogen in the metal and with the target
temperature by the variable-pressure method, using formula (3) for the calculations. The pressure was
10162 4 581D162 4 6810'72 4 68101-2 4 6810192
N, atoms/cm2
Fig. 5. Variation of n with the density
of the hydrogen penetrating into tan-
talum.
1 2
3 4
Fig. 6. Variation of 71 with the temper-
ature of the metal.
Declassified and Approved For Release 2013/03/12 : CIA-RDP10-02196R000700040005-9
 Declassified and Approved For Release 2013/03/12 : CIA-RDP10-02196R000700040005-9
measured with an IM-12F manometer designed for measuring vacuum in heated systems. The mano-
meter was placed inside the target chamber. Prior to the measurements, as before, the chamber and
target were heated to ' 600?K for 3 h. The 35-keV Hi hydrogen-ion beam was recorded electrically, us-
ing a cutoff voltage applied to the HCP surrounding the target. The ares of target surface bombarded
by the ions was determined visually from the erosion trances on the target. Traces of erosion were
clearly visible on all the metals studied up to about 300?K. For target temperatures above 300?K there
were no noticeable traces of erosion. For temperatures above 3000K the area of the bombarded surface
was therefore taken as equal to that measured at lower temperatures for the same settings of the ion
source and focusing system,
In order to study the interaction of the hydrogen ions with the metals, we chose two types of metal:
those forming weak chemical bonds with hydrogen (nickel and stainless steel) and those forming strong
bonds (titanium and tantalum). The penetration of hydrogen ions into stainless steel at normal and
low temperatures was studied with targets constituting hollow argon-arc-welded boxes. The thickness
of the target walls was 1mm. The target was insulated from the chamber by glass junctions, so that
the ion beam current was recorded continuously. During the experiment, the back of the box was cooled
with running water or liquid nitrogen passed through the hollow part of the box. The target was polished
mechanically and washed in gasoline and alcohol. Electrolytic polishing of the targets, carried out after
mechanical polishing, with subsequent washing in distilled water, had very little effect on the results
of the measurements.
Curve 2 of Fig. 2 was obtained for a stainless-steel target cooled by running water to 300?K; curve
3 was obtained for a target cooled to 78?K with liquid nitrogen. In addition to this, we measured 71 with
a target cooled by liquid hydrogen, for which the target construction was slightly modified. The results
of measurements at 24 to 78?K were almost identical. We see from the curves that the results obtained
with a normal target temperature differed considerably from those obtained at low temperatures, both
in the value of q and in the hydrogen density which 71 began falling.
Investigations were carried out at high temperatures with thin targets (0.1 to 0,2 mm) , carefully
degassed by ohmic heating at temperatures close to the melting point. The target temperature was
calculated from the thermal-radiation formula. Degassing at these temperatures was stopped when the
evolution of gas from the target became insignificant. After this the target temperature was reduced to
some 1100 or 1200?K, liquid hydrogen was poured into HCP-1, and the degassing of the target by ionic
bombardment began. This was necessary because even the long and continuous degassing at temperatures
near the melting point was insufficient to degas any of the metals under examination completely. This
was proved by the fact that on bombarding the target after thermal degassing there was a fall in the gas -
evolution coefficient with rising number of ions striking the target. The gas-evolution coefficient became
constant after the density of the ions striking the target exceeded (1 to 5)'1018 cm-2, Analysis of the gases
desorbed'by ion bombardment at these temperatures was not carried out. In view of the fact that these
gases were clearly recorded by the ionization manometer, despite the HCP surrounding the target, it
was reasonable to suppose that these were gases condensing poorly (or not at all) at 20.4?K. This
suggests hydrogen. We should not that the total amount of gases evolving from stainless steel and nickel
as a result of this procedure was greater than that indicated in [4]. After degassing by ion bombardment,
a further brief degassing at a temperature close to the melting point was carried out. After the target
had been prepared in this way, the variation of 17 with the density of the hydrogen pentrating into the metal
was measured. The results obtained for stainless steel at a target temperature around 1100?K are shown
in Fig. 2. (curve 4). Measurements at higher temperatures involved difficulties which have not yet been
overcome.
Figure 3 shows the results of measurements for nickel. Curves 1 and 2 were obtained on targets
cooled with liquid nitrogen (to 78?K) and running water (to 300?K) respectively. We see that, for normal
temperatures of the nickel target, the curve lines much lower than the corresponding curve for stainless
steel (see Fig. 2). At low temperatures the curves for nickel and stainless steel are practically
identical. Curve 3 in Fig. 3 was obtained for a thin target (0.025 mm) at about 1100?K.
The measurement of 77 as a function of hydrogen density in titanium at normal and low temperatures
was carried out in the same way as for stainless steel, using targets constructed in a special box-like
form, cooled with running water or liquid nitrogen. In addition to this, we made measurements on a
target cooled by mechanical contact with the HCP. In this case the target temperature was estimated as
approximately 200?K. Curve 2 in Fig. 4 was obtained by cooling the titanium target with liquid nitrogen to 78?K,
Declassified and Approved For Release 2013/03/12 : CIA-RDP10-02196R000700040005-9
 Declassified and Approved For Release 2013/03/12 : CIA-RDP10-02196R000700040005-9
The curve for 200?K differed very little from this latter, and accordingly it, is not shown in the figure.
It should be noted that the fall in the penetration coefficient of Hi ions penetrating into titanium begins
at rather lower hydrogen concentrations than in the case of stainless steel or nickel. Curve 1 in Fig. 4
was obtained on cooling the target with running water to 300?K. It is an interesting point that the value
of 71 remains unchanged over the range of hydrogen concentrations considered. Similar results were
obtained for a target temperature of'400?K, ? The- value of r] fell as the temperature rose further. Curve
3 was obtained for a thin target (0,025 mm) heated to about 1100?K.
Figure 5 shows the results of measurements made with tantalum. Curve 1 was obtained at a
temperature of ^400?K. Curve 2 was obtained at 1200?K on a thin target (0,025 mm thick). No measure-
ments were made at low temperatures.
It follows from Figs. 2 to 4 that, at low temperatures, the curves are practically the same for all
the metals studied. The difference between metals forming weak and strong chemical bonds with hydrogen
is that at low temperatures the value of 17 for metals forming strong chemical bonds with hydrogen begins
to fall at rather lower hydrogen concentrations. This is probably due to the presence of a large quantity
of dissolved gases in these metals. At normal temperatures, no fall in 71 is observed for titanium and
tantalum over the concentration range studied, whereas for metals forming weak chemical bonds with
hydrogen the value of 17 falls at hydrogen concentrations of about 1.1019 cm-2 (by a factor of 2 for stain-
less steel and 3 for nickel). At high temperatures and low hydrogen concentrations in the metal, the
value of 77 falls sharply (to between 0 and 0.15) for all the metals studied. As.shown by the figures,
complete target saturation with hydrogen at high temperatures only occurs for tantalum. We see from
the curves that the variation of the penetration coefficient with temperature differs for different hydrogen
concentrations. Figure 6 shows the il/T relationship for stainless steel, nickel, titanium, and tantalum
(curves 1, 2, 3, and 4) in the range corresponding to large concentrations of hydrogen (after the fall in
the value of 77 ). The broken (dot-dash) lines show the temperature ranges not studied. It should be
noted that the experiments on titanium and tantalum at 400 300?K this phenomenon may be explained by the ordinary diffusion of the absorbed hydrogen into the
metal. In fact, if we suppose that, in the course of bombardment, a hydrogen concentration of ^' 1015
atoms/cm2 is created in the metal, in a layer dx = 10-6 cm, at a depth equal to the free path of the Hi
ions (this is quite acceptable), then the flow of hydrogen through a plane at a distance d = 10-3 cm from
the layer dx may be determined from the formula
q=DC 11 , , (4)
where D is the diffusion coefficient of the hydrogen atoms and C is their concentration. For a concentra-
tion of - 1015 atoms/cm2 the volume concentration will equal - 1021 atoms/cm3, The diffusion coefficient
for stainless steel may be taken as 10-9 cm2/sec [5], so that q = 1015 atoms/sec, which approximately
equals the flow of ions to the target.
J
dS
Declassified and Approved For Release 2013/03/12 : CIA-RDP10-02196R000700040005-9
 Declassified and Approved For Release 2013/03/12 : CIA-RDP10-02196R000700040005-9
Whereas at above 300?K the results obtained may be explained by ordinary diffusion of the absorbed
hydrogen into the metal, this explanation is completely inadequate at low temperatures. Modern views
on the diffusion of gases in metals indicate an exponential relationship between the diffusion coefficient
and temperature D-a-E/RT; hence at low temperatures the diffusion of gases in metals should be almost
negligibly small. We should thus expect that when hydrogen ions Hi penetrate into metals at low tempera-
tures the concentration of hydrogen in the surface layer will very quickly reach such a value that the
penetration coefficient will fall to zero. At high temperatures the penetration coefficient will also equal
zero at certain concentrations, but this time on account of the high diffusion velocity of the hydrogen. At
high temperatures the expected results were in fact obtained. At low temperatures, however, the ex-
perimental data contradicted the ordinary views regarding the diffusion of hydrogen in metals. We are
not yet sure why this is so. In order to discover the physicochemical nature of the capture and retention
of hydrogen ions in metals, we studied the time dependence of the desorption velocity of absorbed hy-
drogen. The results .of this investigation will be published in a later paper.
The results so far obtained lead to the following conclusions.
1. The greatest penetration coefficient and the greatest gas capacity (relative to hydrogen) are
found in metals forming strong chemical bonds with hydrogen. These metals are suitable for capturing
fast particles in magnetic traps.
2. The number of reflected ions is no greater than a few percent for any of the metals studied, as
indicated by the value of 77 at low concentrations of absorbed hydrogen.
1.
V.
A. Simonov, Nuclear Fusion [in Russian], Pt. 1, Vienna, MAGATE, p. 325
(1962).
2.
E.
S. Borovik, N. P. Katrich, and G. T. Nikolaev, Atomnaya Energiya, 18,
91 (1965).
3.
E.
Segre, Experimental Nuclear Physics, Vol, 1,Wiley, N. Y, (1953).
4.
S. Dushman and J. M. Lafferty, Scientific Foundations of Vacuum Technique, 2nd ed., Wiley,
N. Y.. (1962).
5.
R. Barrer, Diffusion in Solids [Russian translation], Moscow, IL, (1948).
Declassified and Approved For Release 2013/03/12 : CIA-RDP10-02196R000700040005-9
 Declassified and Approved For Release 2013/03/12 : CIA-RDP10-02196R000700040005-9
METHOD OF CALCULATING THE INTENSITY OF
BACK-SCATTERED -y-RADIATION
Formulas and graphs enabling the energy flux density of back-scattered
y -radiation from certain widely-used isotopes (Co??, Cs137, Au198, Cr51) to be
calculated are presented for several typical cases, for example, narrow and
wide beams of y -quanta falling at different angles on to a scattering surface,
and an isotropic source in contact with the surface of a reflector. The accu-
racy of calculations based on these formulas is ? 20%. The method here pre-
sented constitutesthe first attempt to produce engineering formulas and nomo-
grams for determining quantities of scattered y -radiation.
The formulas and graphs presented in this paper give the energy flux density of back-scattered
y -radiation at various distances from the source for several cases frequently found in industrial and
laboratory practice: a narrow beam striking the surface of scattering material at various angles, an
isotropic source in contact with a surface, and a plane unidirectional flow of 'Y-quanta. Presently-known
theoretical and experimental data give insufficiently general relationships for solving problems of a
quantitative nature in connection with scattered y -radiation, although a combination of existing data[l-11]
may be used for calculating the majority of practically interesting cases.
The geometrical aspects of the scattering process are illustrated in Fig. la and b.
200
Fig. 1. To illustrate the notation used
in the text (9 azimuthal scattering an-
gle; a incident angle; co, latitudinal an-
gle).
180 165 150 f35 120
8, deg
Fig. 2. Distribution function J0 (0, co,
R0) for the y-radiation of Au198 (nor-
mal incidence of a narrow beam).
Translated from Atomnaya Energiya, Vol. 21, No. 5, pp. 345-356, November, 1966, Original
article submitted April 1, 1966.
Declassified and Approved For Release 2013/03/12 : CIA-RDP10-02196R000700040005-9
 Declassified and Approved For Release 2013/03/12 : CIA-RDP10-02196R000700040005-9
Narrow Beam of y-Quanta [6, 10]. The energy flux density of radiation scattered in a direction
given by the angles 0 and cp at a distance R may be determined from the formula
J (0,(p, R) = Jo (0, W, Ro) R52K, MeV/cm2 ?sec, (1)
where Jo (0, (p, R0) is the distribution function, Q is the strength of the source in quanta/sec, E is the
energy of the primary quanta in MeV, E2 is the solid angle into which the primary radiation is emitted,
and R is the distance between the detector and the intersection of the narrow beam with the scattering
surface.
According to [6], the empirical constant K equals 8.9.10-7 for the y-radiation of Colo (E ^-1.25 MeV)
at normal incidence on the scattering substance and 9.0.10-6 for oblique incidence; for the y-radiation
of Au198 (E = 0.41 MeV) these values are 3.5.10-6 and 9.8.10-6 respectively. The corresponding values of
the distribution function Jo (0, co, R0) are shown in Figs. 2, 3, 4, and 6.
Formula (1) is applicable for R > 3L, where L is the maximum linear dimension of the spot at the
intersection of the narrow beam of primary radiation with the scattering, surface.
Isotropic Source in Contact with a Surface [7, 8]. The computing formula in this case takes the
form
I (a, ..R) - =.10 (a, HO) O,17QE K MeV/cm2?sec. (2)
The K factor in formula (2) has the following values: for the y-quanta of radioactive Cr51 (E = 0.33
MeV), K=1.39.10-4, for Cs137 (E=0.66 MeV), K=7.14.10-5, and for Co60 K=7.7.10-5 [7]. The values
of the distribution function Jo (a, R0) are shown in Figs.5, 7, and 8.
0
NN
a0?
1
45-50
13
2
50-55
3
55-60
r
4
60-65
5
65-70
f
6
70-75
15
7
12
7
75-80
3
8
80-85
9
85-95
1s
4
10
95-105
>1
105-115
5
12
115-12
5
17
6
13 125-135
7
14 135-155
18
8 9 10
' 15 155-175
16 175-195
17 195-205
19
18 205-215
19 215-220
20 220225
20
30 60
w, deg
a
NN
e0?
a
1
5-50
5
50-55
3
3
4
55-
65-75
6
5
75-85
7
6
85-95
7
95-115
8
115-135
2
9
135-155
f0
155-?75
11
2
y
1 175 195
-L2_ 195-205
13 205-215
14 215-220
15 220-225
13
15
30 60
W, deg
b
Fig. 3. Distribution function Jo (0, co, R0) of the y radiation of Au198 for the oblique incidence of a narrow
beam on various scattering materials : a) lead, a = 450 ; b) iron a = 45? ; c) aluminum, a = 45? ; d) lead,
ce = 60? ; e) iron a = 60? ; f) aluminum, a = 60?,
Fig. 3 continued on p. 1026
Declassified and Approved For Release 2013/03/12 : CIA-RDP10-02196R000700040005-9
 Declassified and Approved For Release 2013/03/12 : CIA-RDP10-02196R000700040005-9
Fig. 3. (continued).
NN
4B'
7/7
45-50
3
2
50-55
3
55-60
2
4
60-65
5
65-75
6
75-85
6
7
85-95
8
95-105
7
fl
EE
12
155-175
g
13
175-195
10
14
195-205
15
205-215
16
215-220
17
220-225
f3
14
15
11
12
16
(7
co, deg
C
-
NN
48`
4
1
30 -35
3
35-40
_40-45
--
--
--
4
4550
6
5
-
1 50-60
6
71
60-70
70-80
7
---
8
80-90
9
90-110
2
10
110-130
8
11
130-150-
12
150-170
9
13
170-180
14
180-190
10
15
190-200
16
200-205
17
205-210
12
14
13
~
15
f7
400
4
NN
d8'
5
i
30-35
2
35-40
3
40-45
6
4
45-50
5
50-55
6
55-60
7
7
60-65
8
65-70
9
70-80
10
80-90
11
.90-110
12
110-130
13
130-150
4
1
15
150=17_0
170-190
16
190-200
17
200-205
LLB_
. 205-210
15
f6
6
17
f0
11
13
14
f2
1
fB
NN
48'
1
30-35
2
35-40
3
40-45
4
45-50
5
50-60
4
6
60-80
7
80-100
5
8
9
100-120
120-140
f0
140-160
11
160-180
2
180-190
13
190-200
6
14
200-205
15
205-210
8
rtI2
13
14
15
10
W, deg
d
cp, deg
f
Declassified and Approved For Release 2013/03/12 : CIA-RDP10-02196R000700040005-9
 Declassified and Approved For Release 2013/03/12 : CIA-RDP10-02196R000700040005-9
(P, deg
a
NN
a0?
f
45-50
2
2
50-55
3
55-60
4
60-65
5
65-70
4
6
__707075-_
- -
--
-
7
75-80
8
80-90_
5
9D-11C_-
10
110-120
11
120-130
12
100 -140
f3
140-150
14
f50-f60
1
15
160-170
8
15
170-180
17
180-190
18
190-200
19
200-210
9
20
210-220
21
220-225
f0
12
13
14
15
16
17
-
1B
19
2
21
NIV
f
45-_370
3
2
50 - 55'
3
55 - 60
4
60 - 65
5
65-70
6
70 -75
6
7
75-80
8
90-85
5
7
9
85-90
f0
90-100
11
100-120
e
4
-
9
12
13
120
1
0
140-160
14
160-180
fo
15
16
180-200
200-210
17
210-220
1
18
220-225
11
12
3
1
7
M
100
100
NN
5
1
45-50
2
50-55
3
3
55-60
4
60-65
5
65-70
6
6
70-75
7
75-80
7
8
80-85
9
85-90
f0
90-95
9
11
95-110
12
110 -130
13
130-
0
-
>5
14
150-170
15
170 -190
16
190 200
17
200-210
18 210-215
f2
f9 215-220
20 220-225
l3
17
15
16
19
20
cp, deg
b
NN
18?
1
30-35
7
35 -40
-
5
3
4
4 50
b
6UTG'
7
70-80
1
8
80 9v
6
9
90-100
iv
rov-110
11
110-120
7
1