Properties of Fe, Ni and Zn isotope chains near the drip-line
The location of proton and neutron drip-lines and the characteristics of the neutron-deficient and the neutron-rich isotopes Fe, Ni and Zn on the basis of Hartree-Fock method with Skyrme forces (Ska, SkM*, Sly4) taking into account deformation was investigated. The calculations predict a big jump of...
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irk-123456789-1101582016-12-31T03:01:51Z Properties of Fe, Ni and Zn isotope chains near the drip-line Tarasov, V.N. Tarasov, D.V. Gridnev, K.A. Gridnev, D.K. Kartavenko, V.G. Greiner, W. Kuprikov, V.I. Ядерная физика и элементарные частицы The location of proton and neutron drip-lines and the characteristics of the neutron-deficient and the neutron-rich isotopes Fe, Ni and Zn on the basis of Hartree-Fock method with Skyrme forces (Ska, SkM*, Sly4) taking into account deformation was investigated. The calculations predict a big jump of deformation parameter up to β ~ 0.4 for Ni isotopes in the neighborhood of N ~ 62. The manifestation of magic numbers for isotopes ⁴⁸Ni, ⁵⁶Ni, ⁷⁸Ni and also for the stable isotope in the respect to neutron emission ¹¹⁰Ni which is situated beyond the neutron drip-line is discussed. На основі метода Хартрі-Фока з силами Скірма (Ska, SkM*, Sly4) при врахуванні деформації досліджено положення протонної і нейтронної границі стабільності і характеристики нейтронодефіцітних і нейтрононадлишкових изотопів Fe, Ni и Zn. Розрахунки зазбачають, що для изотопів Ni в околі N ~ 62 спостерігається великий стрибок величини параметра деформації до β ~ 0.4. Обговорюються прояви магічних чисел для изотопів нікеля ⁴⁸Ni, ⁵⁶Ni, ⁷⁸Ni, а також для нейтроностабільного изотопа ¹¹⁰Ni , який знаходиться за межами границі стабильності. На основе метода Хартри-Фока с силами Скирма (Ska, SkM*, Sly4) при учете деформации исследовано положение протонной и нейтронной границы стабильности и характеристики нейтронодефицитных и нейтроноизбыточных изотопов Fe, Ni и Zn. Расчеты предсказывают, что для изотопов Ni в окрестности N ~ 62 наблюдается большой скачок величины параметра деформации до β ~ 0.4. Обсуждается проявление магических чисел для изотопов никеля ⁴⁸Ni, ⁵⁶Ni, ⁷⁸Ni, а также для нейтроностабильного изотопа ¹¹⁰Ni, который находится за пределами границы стабильности. 2007 Article Properties of Fe, Ni and Zn isotope chains near the drip-line / V.N. Tarasov, D.V. Tarasov, K.A. Gridnev, D.K. Gridnev, V.G. Kartavenko, W. Greiner, V.I. Kuprikov // Вопросы атомной науки и техники. — 2007. — № 5. — С. 3-8. — Бібліогр.: 23 назв. — англ. PACS: 21.60.Jz, 21.10.Dr http://dspace.nbuv.gov.ua/handle/123456789/110158 en Вопросы атомной науки и техники Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
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Ядерная физика и элементарные частицы Ядерная физика и элементарные частицы |
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Ядерная физика и элементарные частицы Ядерная физика и элементарные частицы Tarasov, V.N. Tarasov, D.V. Gridnev, K.A. Gridnev, D.K. Kartavenko, V.G. Greiner, W. Kuprikov, V.I. Properties of Fe, Ni and Zn isotope chains near the drip-line Вопросы атомной науки и техники |
| description |
The location of proton and neutron drip-lines and the characteristics of the neutron-deficient and the neutron-rich isotopes Fe, Ni and Zn on the basis of Hartree-Fock method with Skyrme forces (Ska, SkM*, Sly4) taking into account deformation was investigated. The calculations predict a big jump of deformation parameter up to β ~ 0.4 for Ni isotopes in the neighborhood of N ~ 62. The manifestation of magic numbers for isotopes ⁴⁸Ni, ⁵⁶Ni, ⁷⁸Ni and also for the stable isotope in the respect to neutron emission ¹¹⁰Ni which is situated beyond the neutron drip-line is discussed. |
| format |
Article |
| author |
Tarasov, V.N. Tarasov, D.V. Gridnev, K.A. Gridnev, D.K. Kartavenko, V.G. Greiner, W. Kuprikov, V.I. |
| author_facet |
Tarasov, V.N. Tarasov, D.V. Gridnev, K.A. Gridnev, D.K. Kartavenko, V.G. Greiner, W. Kuprikov, V.I. |
| author_sort |
Tarasov, V.N. |
| title |
Properties of Fe, Ni and Zn isotope chains near the drip-line |
| title_short |
Properties of Fe, Ni and Zn isotope chains near the drip-line |
| title_full |
Properties of Fe, Ni and Zn isotope chains near the drip-line |
| title_fullStr |
Properties of Fe, Ni and Zn isotope chains near the drip-line |
| title_full_unstemmed |
Properties of Fe, Ni and Zn isotope chains near the drip-line |
| title_sort |
properties of fe, ni and zn isotope chains near the drip-line |
| publisher |
Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
| publishDate |
2007 |
| topic_facet |
Ядерная физика и элементарные частицы |
| url |
http://dspace.nbuv.gov.ua/handle/123456789/110158 |
| citation_txt |
Properties of Fe, Ni and Zn isotope chains near the drip-line / V.N. Tarasov, D.V. Tarasov, K.A. Gridnev, D.K. Gridnev, V.G. Kartavenko, W. Greiner, V.I. Kuprikov // Вопросы атомной науки и техники. — 2007. — № 5. — С. 3-8. — Бібліогр.: 23 назв. — англ. |
| series |
Вопросы атомной науки и техники |
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| fulltext |
PROPERTIES OF Fe, Ni AND Zn ISOTOPE CHAINS NEAR
THE DRIP-LINE
V.N. Tarasov1∗, D.V. Tarasov1, K.A. Gridnev2,3, D.K. Gridnev2,3,
V.G. Kartavenko3,4, W. Greiner3, V.I. Kuprikov1
1National Science Center ”Kharkov Institute of Physics and Technology”, 61108, Kharkov, Ukraine
2Institute of Physics, St. Petersburg State University, Russia
3Frankfurt Institute of Advanced Studies J.W.G. University, Frankfurt, Germany
4Joint Institute for Nuclear Research, Dubna, Russia
(Received April 21, 2007)
The location of proton and neutron drip-lines and the characteristics of the neutron-deficient and the neutron-rich
isotopes Fe, Ni and Zn on the basis of Hartree-Fock method with Skyrme forces (Ska, SkM*, Sly4) taking into account
deformation was investigated. The calculations predict a big jump of deformation parameter up to β ∼ 0.4 for Ni
isotopes in the neighborhood of N ∼ 62. The manifestation of magic numbers for isotopes 48Ni, 56Ni , 78Ni and
also for the stable isotope in the respect to neutron emission 110Ni which is situated beyond the neutron drip-line is
discussed.
PACS: 21.60.Jz, 21.10.Dr
1. The structure of nuclei which are very far
from the valley of stability and the location of proton
and neutron drip-lines are one of the most impor-
tant tasks of nuclear physics. The nuclei with neu-
tron excess are region of great interest [1, 2, 3, 4, 5].
However the question about the existence of stability
islands of the nuclei with a very big neutron excess
is not studied enough up to now. In our previous
works [6, 7] we presented the results of our investi-
gations in search of very neutron-rich stable nuclei
which are far beyond neutron nuclear drip-lines on
the basis of Hartree-Fock (HF) method with Skyrme
forces accounting deformation (DHF). In particular,
for neutron-rich nuclei with 6 ≤ Z ≤ 16 in the neigh-
borhood of neutron nuclear drip-line it was predicted
the existence of a stability peninsula which rests on
the isotope 40O.
A lot of attention has been given recently to the
study of the properties of the neutron-deficient and
the neutron-rich nuclei in the region of Fe and Ni
[8, 9]. Doubly magic neutron-deficient isotope 48Ni
[10] and doubly magic isotope 78Ni [11] have been
experimentally discovered lately.
In the present paper we theoretically investigated
the location of proton and neutron drip-lines for Fe,
Ni and Zn isotopes on the basis of HF method with
Skyrme forces accounting deformation.
2. Rather clear and complete description of HF
method one can find in [12]. In our calculations we
used the parameterisation of Skyrme forces Sly4 [13],
SkM* [14] and Ska [15]. Pairing effects were in-
cluded in the BCS approximation and only in the
space of bounded one-particle states with the pair-
ing constant G = (19.5/A)[1± 0.51(N − Z)/A] [16],
where the sign ”+” corresponds to the protons but
the sign ”-” corresponds to the neutrons. The jus-
tification of applicability of this approximation was
given in [6, 7].
We have used the iteration method to solve the
system of DHF equations which is described in de-
tails in [7, 17, 18]. In this method required one-
particle wave functions DHF are expanded in series
of complete set of eigenfunctions of axially deformed
harmonic oscillator with the frequencies ωr and ωz
. The parameters of basis q = ωr/ωz and β0 =
[m(ω2
rωz)1/3/h̄]1/2 have been chosen on each itera-
tion such that the total energy of nucleus E = (q, β0)
was minimal. The optimization of q and β0 [7, 18]
on each iteration is important for the calculations of
weakly bounded neutron-rich nuclei near the drip-
line. The densities of neutron distributions of such
systems have big root mean squares radii and can
have neutron halo [1, 2, 3, 4, 5]. That’s why it is
important to describe correctly the asymptotic be-
havior of wave functions for big r. In our calcula-
tions the decrease of optimal β0 with approaching to
neutron drip-line is always accompanied by increase
of the calculated root mean squares radii. Thus, in
our case, the asymptotic behavior of basis wave func-
tions changes depending on space spread density with
guaranteeing the highest value of nuclear binding en-
ergy.
3. Let’s go over the results of our calculations
comparing with the data which were obtained on the
∗Corresponding author. E-mail address: vtarasov@kipt.kharkov.ua
PROBLEMS OF ATOMIC SCIENCE AND TECHNOLOGY, 2007, N5.
Series: Nuclear Physics Investigations (48), p.3-8.
3
basis of Hartree-Fock-Bogoliubov (HFB) method by
the group of authors M.V. Stoitsov, J. Dobaczewski,
W. Nazarewicz et.al. in [19].
3.1. Ni isotopes. In our calculations for Ska
forces the separation energies of one proton Sp for
neutron-deficient Ni isotopes remain positive up to
48Ni including. The last isotope Ni stable in the
respect to one proton emission (proton-stable) cor-
responds to doubly magic neutron-deficient isotope
48Ni which has been experimentally discovered re-
cently [10]. This result differs from the data obtained
in [9] where proton instability of isotope 48Ni was pre-
dicted, as the proton drip-line defined by means of
the condition for chemical potential λp=0 does not
correspond to experimental data [10]. The proton
drip-line defined by means of the condition Sp = 0
does not change if we use SkM* and Sly4 forces.
0
6
12
18
24
30
40 50 60 70 80 90 100 110 120
0
6
12
18
24
30
0
6
12
18
24
30
48Ni
S
n (
M
eV
)
Sn Exp
Sn HF (Ska)
n HFB (Sly4)Dobaczewski
Ni
78Ni
a
S
n (
M
eV
)
Sn HF (Sly4)
Sn Exp
n HFB (Sly4)Dobaczewski
Ni
78Ni
48Ni c
A
S
n (
M
eV
)
Sn Exp
Sn HF (SkM*)
n HFB (SkM*)Dobaczewski
Sn HF (SkM*) Spherical
Ni
78Ni
48Ni
b
Fig.1. Separation energies of one neutron Sn
for Ni isotopes depending on A compared to the
experimental data [20] and to the values of neutron
chemical potentials λn (Dobaczewski J.) [19] for
forces Ska, SkM* and Sly4. In figure 1b in the
vicinity of A = 110 additionally are shown the data
for the spherical HF+BCS calculations
Fig.1 shows the experimental [20] and calculated
separation energies of one neutron Sn for different
variants of effective forces used in our calculations.
It is seen from figure 1a that the dependence Sn from
A for Ska forces has specific sharp bends connected
with filling of corresponded neutron subshells: spe-
cific sharp bend for 48Ni is caused by filling neutron
subshell νs1/2 , for 56Ni by νf7/2, for 68Ni by νp1/2 ,
for 78Ni by νg9/2. The last isotope with positive value
of Sn is the isotope 106Ni. Isotope 108Ni any more is
not the stable isotope with respect to one-neutron
emission (neutron-unstable), but the isotope 110Ni
again becomes neutron-stable with Sn =0.483 MeV.
Such increase of stability 110Ni is connected with fill-
ing neutron subshell νh11/2 . For 56Ni, 78Ni and 110Ni
increase of value Sp is also observed. For these nuclei
the corresponding mentioned above neutron subshells
and proton subshell πf7/2 are completely filled. In
this case the increase of separation energies of neu-
tron and proton can be considered as manifestation
of magic numbers Z=28, N=20,28,40,50,82. In our
calculations it corresponds to zero value of the neu-
tron energy gap ∆n calculated for mentioned above
G .
The results presented on figure1b for SkM* forces
qualitatively poorly differ from the results for forces
Ska, showing some stability with respect to a choice
of forces, and in particular of increase of stability with
respect to emission of neutrons at A=110 ( Sn=0.755
MeV). In contrast to forces Ska, the results obtained
for forces SkM* show specific sharp bend in depen-
dence Sn on A which corresponds to N=32 and to
filling of a subshell νp3/2 , and also ∆n=0. Rein-
forcement of stability of nuclei at N=32 was noticed
earlier [6, 7] for the isotope 40O , and also in work
[21]. At the same time for forces SkM* and N=40
the energy gap is ∆n 6=0. Therefore, for isotopes Ni
manifestation of magic numbers N=32,40 is unstable
in relation to a choice of forces.
For forces Sly4 (Fig.1, c) the neutron drip-line
corresponds to 92Ni and some splash of stability is
observed for 98Ni , that corresponds to completely
filled subshell νg7/2. We shall note, that force Sly4
always give less bounded decisions and neutron drip-
line corresponds to smaller A in comparison with the
calculations for forces Ska and SkM*. For forces Sly4,
as well as for forces SkM*, in dependence Sn on A spe-
cific sharp bend corresponding to N=32 is observed.
Similarly to proton drip-line , the drip-line in the re-
spect to emission of one neutron, determined by a
condition λn=0, does not coincide with position of
drip-line determined of the condition Sn =0.
Discussing filling of subshells for of some isotopes
Ni, we used classification of states corresponding to
spherical symmetry of an average field. It is possible
if in addition to make calculations within the limits
of method HF [22] directly in coordinate space with
spherical symmetry of an average field (SHF). The
use of SHF is motivated as, in all the cases we con-
sidered, specific sharp bend of value Sn corresponds
to the decisions obtained within the limits of DHF
which have spherical distribution of density.
Let’s consider now the character of change for
separation energies of two neutrons S2n depend-
ing on A for forces Ska, SkM* and Sly4 in HF
calculations and in comparison with HFB [19].
These results are shown on Fig.2. The sepa-
ration energies of two neutrons is determined as
4
S2n(Z, N) = E(Z, N)− E(Z, N − 2), where E is full
binding energy of a nucleus. As it is seen in Fig.2,
the calculations on the basis of HF and the calcu-
lations HFB approximately with the same quality
describe available experimental data for separation
energies of two neutrons S2n. As well as for Sn,
the results of calculations S2n for forces Ska and
SkM* show, that these forces provide greater stabil-
ity of nuclei in the respect to emission of two neu-
trons, than forces Sly4. The discussed specific sharp
bends in dependence Sn and S2n on A are observed
at the same N, and their position equally depends
on a choice of forces. We cannot calculate separa-
tion energy of two neutrons S2n for 110Ni since the
neighbouring isotopes are unstable. As it is seen in
Fig.2, the drip-line in the respect to separation of
two neutrons is located at smaller values N, than
drip-line in the respect to separation of one neutron.
0
15
30
45
0
15
30
45
40 50 60 70 80 90 100 110 120
0
15
30
45
S 2n
(M
eV
)
S2n Exp
S2n HF (Ska)
S2n HFB (Sly4)Dobaczewski
Ni
a
S 2n
(M
eV
)
S2n Exp
S2n HFB (SkM*)Dobaczewski
S2n HF (SkM*)
Ni
b
S 2n
(M
eV
)
A
S2n Exp
S2n HFB (Sly4)Dobaczewski
S2n HF (Sly4)
Ni
c
Fig.2. The separation energies of two neutrons
S2n for Ni isotopes depending on A compared to
the experimental data [20] and the data obtained in
HFB calculations (Dobaczewski J.) [19] for forces
Ska, SkM* and Sly4
It is rather unexpected that the results for calcu-
lations of S2n by method HF and HFB completely
coincide if the calculations are made with the same
types of forces (see Fig.2, b and Fig.2, c). Such good
description of separation energies of two neutrons S2n
for the considered region of nuclei in comparison with
the method HFB in which pairing is made includ-
ing continuum, gives the basis, contrary to histori-
cally accepted opinion [2, 9], to use our version of
method HF+BCS for research of properties of nu-
clei near the drip-line. As additional argument in
favour of it we can consider the results which we ob-
tained for the root mean square radii 〈r2
n,p〉1/2 which
are presented in Fig.3, in comparison with data [19].
40 50 60 70 80 90 100 110 120
3,0
3,6
4,2
4,8
5,4
3,0
3,6
4,2
4,8
5,4
<r
2 n;
p>1/
2 (fm
)
A
rp HFB (SkM*)Dobaczewski
rn HFB (SkM*)Dobaczewski
rp HF (SkM*)
rn HF (SkM*)
Ni
b
<r
2 n;
p>1/
2 (fm
)
rp HF (Ska)
rn HF (Ska)
Ni
a
Fig.3. Neutron and proton root mean square
radii 〈r2
n,p〉1/2 of Ni isotopes depending on A for
forces Ska, SkM* and the data obtained in HFB
calculations (Dobaczewski J.) [19] for forces SkM*
Just bad description 〈r2
n〉1/2 for isotopes Ni [2],
was in due time the basis for the statement about
non-applicability of the HF+BCS method for calcu-
lations of properties of extremely neutron-rich nuclei.
The wrong asymptotic behavior of basic wave func-
tions of harmonic oscillator [19] was considered as the
important reason of non-applicability HF+BCS for
the description of nuclei close to drip-line. We shall
note, that in pairing on the basis of BCS we take
into account in our calculations only the bounded
one-particle states and consequently influence of con-
tinuum explicitly is not considered, and asymptotic
behavior of basic wave functions is corrected by the
procedure of optimization of oscillator parameters q
and β0 on each iteration. As it is seen in Fig.3, b, the
agreement radii 〈r2
n,p〉1/2 with data given in [19] more
than good. As we explicitly do not consider influence
of continuum, it is possible to assume, that correct
asymptotic behavior of density for big value of radii
5
r has the defining value for the description of 〈r2
n,p〉1/2
. Data [19] for value radii 〈r2
n,p〉1/2 correspond to sta-
ble isotopes in respect to emission of two neutrons.
The dip in value radii 〈r2
n,p〉1/2 is connected with the
spherical shape of 110Ni, and jump in value 〈r2
p〉1/2
in the vicinity A=90 is connected with big jump in
value of deformation parameter βp . In process of
increase of neutron excess the value of the 〈r2
n〉1/2 ex-
ceeds the 〈r2
p〉1/2 , and approaching to drip-line, this
excess becomes very big. For extremely neutron-rich
isotopes Ni we can speak about presence of neutron
skin.
The data for neutron and proton parameters of
quadrupole deformation βn,p are presented in Fig.4.
10 20 30 40 50 60 70 80 90
-0,2
0,0
0,2
0,4
-0,2
0,0
0,2
0,4
N
n,
p
n HF (SkM*)
p HF (SkM*)
HFB (SkM*)Dobaczewski
Ni b
n,
p
n HF (Ska)
p HF (Ska)
Ni
a
Fig.4. Neutron and proton parameters of quadrupole
deformations of isotopes Ni depending on A for
forces Ska, SkM* and the data obtained in HFB
calculations (Dobaczewski J.) [19] for forces SkM*
For the isotopes Ni corresponding to magic numbers
mentioned above the parameters of deformation βn,p
have zero value, and at N ∼ 62 the value of pa-
rameter of deformation very rapidly increases up to
value β ∼ 0.35 − 0.4, and βp is more than βn. We
also note, that 110Ni has spherical form. Significant
increase of deformation near the drip-line is possible
not only for isotopes Ni. For example, in work [23]
on the basis of method HFB with forces Sly4 for
isotopes Zr near to neutron drip-line there is a very
big increase of parameter of quadrupole deformation
up to βn,p ∼ 0.42 ÷ 0.47, that coincides with the
experimental data.
3.2 Fe and Zn isotopes. The investigation of
nuclei with Z-2 and Z+2 with the respect to magic
nucleon with Z=28 is of certain interest. For isotopes
Fe and Zn all the calculations were made only with
forces Ska .
The last stable isotope in the respect to emission
of one proton, as well as in the calculations [19] is
isotope 46Fe, that can be considered as manifestation
of magic number N=20.
For isotopes Zn the last stable isotope in the re-
spect to emission of one proton is isotope 54Zn. It
does not coincide with the data of the work [19] for
forces Sly4 where last the stable isotope in the re-
spect to emission of one proton is the isotope 58Zn if
the drip-line is defined by means of chemical potential
λp.
The separation energies of one neutron Sn and
results of calculations λp [19] for forces Sly4 are pre-
sented in Fig.5. It is seen, that dependence Sn on
A for isotopes Fe and Zn differs from similar de-
pendence for isotopes Ni. The shell effects which
are manifested in the form of specific sharp bend
for isotopes Ni are poorly expressed for isotopes Fe.
0
6
12
18
24
40 50 60 70 80 90 100 110 120
0
6
12
18
24
S
n (M
eV
)
Sn Exp
Sn HF (Ska)
n HFB (Sly4)Dobaczewski
Fe
a
S
n (M
eV
)
A
Sn Exp
Sn HF (Ska)
n HFB (Sly4)Dobaczewski
Zn
b
Fig.5. Separation energies of one neutron Sn for
isotopes Fe and Zn for forces Ska depending on A
compared to the experimental data [20] and values
of neutron chemical potentials (Dobaczewski J.) [19]
for forces Sly4
It can be partially explained if to admit, that there
is no reciprocal gain of proton and neutron magic
numbers for isotopes Fe. For isotopes Fe Z=26 is
two units less than the magic number 28 and proton
subshell 1f7/2 is not filled. From A=90 up to A=98
the value Sn > 0, but the value of it is very small.
The last neutron-rich stable isotope is 98Fe and the
stable isotope 102Fe has Sn = 0.146 MeV .
For isotopes Zn Z=30 is two units more than the
magic number 28 and the proton subshell 1f7/2 is
filled, and the next proton subshell 2p3/2 is half-
filled . The neutron-rich isotopes Zn are more sta-
ble than the isotopes Fe in the respect to emission of
6
one neutron. The last neutron-rich stable isotope is
112Zn that corresponds to filling of a neutron subshell
νh11/2 as in the stable isotope 110Ni. The separation
energy of one neutron for 112Zn in DHF calculation
is Sn = 0.87 MeV .
THE CONCLUSION
The research made in the present work for the chains
of isotopes Fe, Ni and Zn on the basis of Hartree-Fock
method with Skyrme forces accounting deformation
allows to extract the following results:
• for Ni isotopes the last stable isotope in the re-
spect to emission of one proton is doubly magic
isotope 48Ni that was proved experimentally
[10];
• beyond the neutron drip-line of nickel isotopes,
coinciding with 106Ni our calculations predict
the existence of neutron-rich isotope 110Ni that
can be to considered as manifestation of magic
number N=82;
• in our calculations for isotopes Ni it was ob-
tained good agreement of S2n and 〈r2
n,p〉1/2 with
the data of calculations based on the method
HFB that gives the basis for application of
the method HF+BCS for studying extremely
neutron-rich isotopes;
• for Ni isotopes approaching to drip-line and
at N=60 the value of deformation parameter
jumps up to βn,p ∼ 0.35 − 0.4 and the isotope
110Ni has spherical form;
• for isotopes Fe the last stable isotope in the re-
spect to emission of one proton is the isotope
46Fe , and for isotopes Zn- 54Zn;
• for isotopes Zn last stable in the respect to emis-
sion of one neutron is 112Zn; it corresponds to
filling of neutron subshell νh11/2 , as well as in
a stable isotope 110Ni .
• the obtained results show that the structure of
the drip-line can be rather complex and it is
connected with the manifestation of shell struc-
ture.
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СВОЙСТВА ЦЕПОЧЕК ИЗОТОПОВ Fe, Ni И Zn ВБЛИЗИ ГРАНИЦЫ
СТАБИЛЬНОСТИ
В.Н. Тарасов, Д.В. Тарасов, К.А. Гриднев, Д.К. Гриднев,
В.Г. Картавенко, В. Грайнер, В.И. Куприков
На основе метода Хартри-Фока с силами Скирма (Ska, SkM*, Sly4) при учете деформации иссле-
довано положение протонной и нейтронной границы стабильности и характеристики нейтронодефи-
цитных и нейтроноизбыточных изотопов Fe, Ni и Zn. Расчеты предсказывают, что для изотопов Ni
в окрестности N ∼ 62 наблюдается большой скачок величины параметра деформации до β ∼ 0.4.
Обсуждается проявление магических чисел для изотопов никеля 48Ni, 56Ni, 78Ni, а также для нейтро-
ностабильного изотопа 110Ni, который находится за пределами границы стабильности.
ВЛАСТИВОСТI ЛАНЦЮЖКIВ IЗОТОПIВ Fe, Ni I Zn ПОБЛИЗУ ГРАНИЦI
СТАБIЛЬНОСТI
В.М. Тарасов, Д.В. Тарасов, К.А. Грiднєв, Д.К. Грiднєв,
В.Г. Картавенко, В. Грайнер, В.I. Купрiков
На основi метода Хартрi-Фока з силами Скiрма (Ska, SkM*, Sly4) при врахуваннi деформацiї до-
слiджено положення протонної i нейтронної границi стабiльностi i характеристики нейтронодефiцiтних
i нейтрононадлишкових iзотопiв Fe, Ni и Zn. Розрахунки завбачають, що для iзотопiв Ni в околi N ∼ 62
спостерiгається великий стрибок величини параметра деформацiї до β ∼ 0.4. Обговорюються прояви
магiчних чисел для iзотопiв нiкелю 48Ni, 56Ni, 78Ni, а також для нейтроностабiльного iзотопу 110Ni,
який знаходиться за межами границi стабiльностi.
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