Resonance-like structure observed in ²⁵Mg(p; γ)²⁶Al reaction
The γ decay of the resonance-like structure (RLS), observed in the ²⁵Mg(p; γ)²⁶Al in the region of excitation energies of 7...9 MeV was studied. The excitation function of the ²⁵Mg(p; γ)²⁶Al reaction was measured. The resonance strengths in the accelerated proton energy range of Eₚ = 1.4...2.0 MeV w...
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Національний науковий центр «Харківський фізико-технічний інститут» НАН України
2017
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irk-123456789-1360742018-06-16T03:03:26Z Resonance-like structure observed in ²⁵Mg(p; γ)²⁶Al reaction Kachan, A.S. Kurguz, I.V. Mischenko, V.M. Utenkov, S.N. Ядерная физика и элементарные частицы The γ decay of the resonance-like structure (RLS), observed in the ²⁵Mg(p; γ)²⁶Al in the region of excitation energies of 7...9 MeV was studied. The excitation function of the ²⁵Mg(p; γ)²⁶Al reaction was measured. The resonance strengths in the accelerated proton energy range of Eₚ = 1.4...2.0 MeV were determined. The obtained distributions of the strength of M1 transitions between the resonance states and the low-lying bound states in ²⁶Al have resonance character. The position of the center of gravity of the magnetic dipole resonance (MDR) on the ground state is equal to 7.92 MeV . Total strength MDR in ²⁶Al is equal to 5.7 MeV μ²ₙ. Вивчено γ-розпад резонансноподібної структури (РПС), що спостерігається в реакції ²⁵Mg(p; γ)²⁶Al в районі енергій збудження 7…9 МеВ. Проведено вимірювання функції збудження даної реакції. Сили резонансних станів визначені в інтервалі енергій прискорених протонів Eₚ = 1.4...2.0 МеВ. Отримані розподіли сили М1 переходів між резонансними станами і низьколежачими пов'язаними в ²⁶Al мають резонансний характер. Положення центра ваги магнітного дипольного резонансу (МДР) на основному стані дорівнює 7,92 МеВ. Повна сила МДР дорівнює 5,7 МеВ μ²ₙ. Изучен γ-распад резонансноподобной структуры (РПС), наблюдаемой в реакции ²⁵Mg(p; γ)²⁶Al в районе энергий возбуждения 7…9 МэВ. Проведены измерения функции возбуждения данной реакции. Силы резонансных состояний определены в интервале энергий ускоренных протонов Eₚ = 1.4...2.0 МэВ. Полученные распределения силы М1 переходов между резонансными состояниями и низколежащими связанными в ²⁶Al имеют резонансный характер. Положение центра тяжести магнитного дипольного резонанса (МДР) на основном состоянии равно 7,92 МэВ. Полная сила МДР равна 5,7 МэВ μ²ₙ. 2017 Article Resonance-like structure observed in ²⁵Mg(p; γ)²⁶Al reaction / A.S. Kachan, I.V. Kurguz, V.M. Mischenko, S.N. Utenkov // Вопросы атомной науки и техники. — 2017. — № 3. — С. 16-20. — Бібліогр.: 17 назв. — англ. 1562-6016 PACS: 25.85.Ig, 27.90.+b, 25.30.Fj, 27.10.+h http://dspace.nbuv.gov.ua/handle/123456789/136074 en Вопросы атомной науки и техники Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
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Digital Library of Periodicals of National Academy of Sciences of Ukraine |
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| topic |
Ядерная физика и элементарные частицы Ядерная физика и элементарные частицы |
| spellingShingle |
Ядерная физика и элементарные частицы Ядерная физика и элементарные частицы Kachan, A.S. Kurguz, I.V. Mischenko, V.M. Utenkov, S.N. Resonance-like structure observed in ²⁵Mg(p; γ)²⁶Al reaction Вопросы атомной науки и техники |
| description |
The γ decay of the resonance-like structure (RLS), observed in the ²⁵Mg(p; γ)²⁶Al in the region of excitation energies of 7...9 MeV was studied. The excitation function of the ²⁵Mg(p; γ)²⁶Al reaction was measured. The resonance strengths in the accelerated proton energy range of Eₚ = 1.4...2.0 MeV were determined. The obtained distributions of the strength of M1 transitions between the resonance states and the low-lying bound states in ²⁶Al have resonance character. The position of the center of gravity of the magnetic dipole resonance (MDR) on the ground state is equal to 7.92 MeV . Total strength MDR in ²⁶Al is equal to 5.7 MeV μ²ₙ. |
| format |
Article |
| author |
Kachan, A.S. Kurguz, I.V. Mischenko, V.M. Utenkov, S.N. |
| author_facet |
Kachan, A.S. Kurguz, I.V. Mischenko, V.M. Utenkov, S.N. |
| author_sort |
Kachan, A.S. |
| title |
Resonance-like structure observed in ²⁵Mg(p; γ)²⁶Al reaction |
| title_short |
Resonance-like structure observed in ²⁵Mg(p; γ)²⁶Al reaction |
| title_full |
Resonance-like structure observed in ²⁵Mg(p; γ)²⁶Al reaction |
| title_fullStr |
Resonance-like structure observed in ²⁵Mg(p; γ)²⁶Al reaction |
| title_full_unstemmed |
Resonance-like structure observed in ²⁵Mg(p; γ)²⁶Al reaction |
| title_sort |
resonance-like structure observed in ²⁵mg(p; γ)²⁶al reaction |
| publisher |
Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
| publishDate |
2017 |
| topic_facet |
Ядерная физика и элементарные частицы |
| url |
http://dspace.nbuv.gov.ua/handle/123456789/136074 |
| citation_txt |
Resonance-like structure observed in ²⁵Mg(p; γ)²⁶Al reaction / A.S. Kachan, I.V. Kurguz, V.M. Mischenko, S.N. Utenkov // Вопросы атомной науки и техники. — 2017. — № 3. — С. 16-20. — Бібліогр.: 17 назв. — англ. |
| series |
Вопросы атомной науки и техники |
| work_keys_str_mv |
AT kachanas resonancelikestructureobservedin25mgpg26alreaction AT kurguziv resonancelikestructureobservedin25mgpg26alreaction AT mischenkovm resonancelikestructureobservedin25mgpg26alreaction AT utenkovsn resonancelikestructureobservedin25mgpg26alreaction |
| first_indexed |
2025-07-09T21:23:10Z |
| last_indexed |
2025-07-09T21:23:10Z |
| _version_ |
1837206016539754496 |
| fulltext |
RESONANCE-LIKE STRUCTURE OBSERVED IN
25Mg(p, γ)26Al REACTION
A.S.Kachan∗, I.V.Kurguz, V.M.Mischenko, S.N.Utenkov
National Science Center ”Kharkiv Institute of Physics and Technology”, 61108, Kharkiv, Ukraine
(Received April 27, 2017)
The γ decay of the resonance-like structure (RLS), observed in the 25Mg(p, γ)26Al in the region of excitation energies
of 7...9MeV was studied. The excitation function of the 25Mg(p, γ)26Al reaction was measured. The resonance
strengths in the accelerated proton energy range of Ep = 1.4...2.0MeV were determined. The obtained distributions
of the strength of M1 transitions between the resonance states and the low-lying bound states in 26Al have resonance
character. The position of the center of gravity of the magnetic dipole resonance (MDR) on the ground state is equal
to 7.92MeV . Total strength MDR in 26Al is equal to 5.7MeV µ2
N .
PACS: 25.85.Ig, 27.90.+b, 25.30.Fj, 27.10.+h
1. INTRODUCTION
In recent years, reactions of inelastic scattering and
radiative capture of protons have been actively used
to study the giant multipole (M1, E2, octupole)
resonances in the region of low excitation energies
and, therefore, falling in the range of discrete nuclear
states [1, 2]. Among the low-lying giant resonances,
M1 is one of the most interesting because M1 tran-
sitions carry the most complete information about
the spin and isospin dependences of nuclear forces
[2]. In real nuclei, the M1 strength is distributed
over neighboring states; this circumstance makes it
possible to study the relationship between the single-
particle and collective motion. For sd shell nuclei,
the role of collective motion is insignificant; there-
fore, the M1 resonance clearly manifests itself in
these nuclei. To date, the position and fine structure
of the magnetic dipole resonance (MDR) in even-
even (4N and 4N + 2n) sd shell nuclei have been
sufficiently well studied [3, 4]. It has also been es-
tablished that the main mechanism responsible for
the MDR excitation is the transitions between spin-
orbit partners [2]. To explain the reduction in the
total strength and MDR fragmentation in these nu-
clei, the Nilsson model [4], the configuration- mixing
shell model [3], and the Hartree-Fock method [5]
were successfully used. Consideration of the effect
of pairing correlations on the position and energy-
weighted strength of giant multipole resonances leads
to more complete agreement between the predictions
of different theoretical models and experimental data
[6, 7]. Behavior of the MDR total strength in odd sd
shell nuclei corresponds to that of the total strength,
which follows from the Kurath sum rule [8]. Analysis
of the MDR total strength in even-even (4N and
4N +2n) sd shell nuclei indicates that the valence nn
and pp pairs play a key role in the MDR formation
in this nuclei [9]. Analysis of the MDR total strength
in odd-odd (4N + np) sd shell nuclei can also give
information about the effect of pairing influence. on
the MDR properties.
2. EXPERIMENTAL RESULTS AND
DISCUSSION
For experimental determination the center of gravity
(Ecog =
∑
k EkBk(M1)/
∑
k Bk(M1) and the total
strength (SM1
EW =
∑
k EkBk(M1) ↑) of the MDR ob-
served in the radiative proton capture reaction, it is
necessary to know resonance strengths for the current
reaction (S = (2I + 1)ΓpΓγ/Γ), since
B(M1)fi ↑=
86.6
2If + 1
bifSi[eV ]
(1 + δ2if )E
3
γif
µ2
N , (1)
here i is the initial (resonance) state; f is the ter-
minal state; bif is the branching ratio for transition
between the initial and the terminal states; Si rep-
resents resonance state strengths; δ is the ratio of
mixing by multipolarities for γ transitions between
the initial and the terminal states; I is the state
spin; is the energy of γ transition between the ini-
tial and the terminal states; Eif is the energy of
γ transition between the initial and the terminal
states; B(M1)fi is the reduced probability of the
M1 transition from the final to the initial state:
(B(M1)fi = ((2Ii + 1)/(2If + 1))B(M1)if ). K is
of the MDR states. Expression (1) below the binding
energy for proton as follows:
B(M1)fi ↑= 14.2
bif (2If + 1)
(1 + δ2if )τmi [fs]E
3
γif
[MeV ]
µ2
N ,
(2)
∗Corresponding author E-mail address: kachan@kipt.kharkov.ua
16 ISSN 1562-6016. PROBLEMS OF ATOMIC SCIENCE AND TECHNOLOGY, 2017, N3(109).
Series: Nuclear Physics Investigations (68), p.16-20.
where mi is the average lifetime of the excited state.
The resonance strengths within the accelerated
proton energy range with Ep < 1MeV are generally
well known, and it is therefore convenient to deter-
mine the resonance strengths being investigated for
the first time on the basis of relative measurements. If
we compare the yield of γ lines within the spectrum of
the resonance investigated to the ones within a spec-
trum of known resonance (with well - known strength
and decay patterns), we can obtain the strength
value for the investigated resonance. The method
for determining resonance strength for thin targets
is described in detail in [10, 11]. We measured the
excitation function for the 25Mg(p, γ)26Al reaction
in the range of proton energies Ep = 1.4...2.0MeV
(Fig.1). The measurements were performed on the
ESU-5 accelerator at the National Scientific Cen-
ter Kharkov Institute of Physics and Technology. A
Ge(Li) detector with volume of 60 cm3 and resolution
of 3.2 keV for Eγ = 1332 keV was used to measure
the γ spectra. The detector was placed at a distance
of 2 cm from the target at an angle of 55◦. The target
was prepared by knocking ions directly into a tan-
talum substrate in the electromagnetic separator. A
target prepared in this manner is convenient for long-
lasting experiments, since it is capable of sustaining
high current densities for many hours of operation.
1700 1800 1900 2000
5000
10000
15000
20000
N
Ep, keV
25Mg(p, )26Al
Fig.1. Excitation function of the 25Mg(p, γ)26Al
reaction. γ photons with Eγ > 2.6MeV was detected
The resonance strengths in the (p, γ) reactions
are determined as in [10]:
S =
(2I + 1)εNγ
4π3λ2ξNpbηW (θ)
, (3)
where ε is the target’s deceleration capability mea-
sured in energy units and multiplied by cm2/atom;
Nγ is the γ quantum yield for the current energy; ξ
is the target thickness measured in energy units; Np
is the number of protons that fell on the target; b is
the branching ratio; η is the detector’s absolute ef-
ficiency; and W (θ) is a coefficient used to consider
the angular distribution effect. The target thickness
ξ may be expressed through deceleration capability
of the target substance
ξ = ntMε , (4)
where n is the number of atoms per 1 g of the target
substance and tM is the target thickness measured
in gcm−2. Measurements over the energy range were
performed under the same experimental conditions,
making it possible to exclude the dependence on the
number of protons that fall on the target and target
thickness:
S1
S2
=
Nγ1Er1b2η2
Nγ2Er2b1η1
, (5)
where and are Nγ1
, Nγ2
quantum yields (the area un-
der the γ line) for the first and the second resonances
respectively; and are the resonance energies of pro-
tons in the laboratory system; b1 and b2 are branch-
ing ratios of the γ transitions under study; η1 and
η2 represent the detector’s absolute efficiency with
respect to γ quanta detected in the first and in the
second resonances, respectively. The results of these
measurements are listed in the Table 1.
In this study, the strengths of the resonances
forming the resonance-like structure observed in the
reaction of proton radiative capture 25Mg(p, γ)26Al
were determined from comparison of the intensities
of the γ lines formed during decay of the resonance
levels under study with the intensity of the γ line
at Eγ = 5153 keV , corresponding to the transition
from the resonance level with Ep = 953 keV (whose
strength and decay scheme are well known) to the
state at 2069 keV .
We also measured the spectra and angu-
lar distributions of γ rays formed at the de-
cay of the most intensive resonances with
Ep = 953, 1375, 1587, 1649, 1699, 1714 keV . The
Ge(Li) detector was located at a distance of 7 cm
from the target. The target was situated in the ro-
tation center at an angle of 45◦ to the proton beam
direction. Measurements were performed at angles
of 0◦, 30◦, 45◦, 60◦ and 90◦. Corrections taking into
account the finite dimensions of the detector were
chosen from the tables. A scintillation detector with
a NaI(T l) crystal served as a monitor. The same
detector was used to measure the excitation function
of the 25Mg(p, γ)26Al reaction. The measurement
results as the expansion coefficients (ak) in Legendre
polynomials are given in Table 2.
The coefficients ak were determined by least-
squares fitting of the experimental data and using
the expression:
W (θ) = A0[1+a2P2(cos θ)+a4P4(cos θ)+a6P6(cos θ)] .
17
Table 1. Resonance strengths in the 25Mg(p, γ)26Al reaction
Ep, keV Ex keV S, eV S, eV [12] S, eV [13] < S >, eV
1375 7628 21±7 14.6±1.2 9±2
1587 7832 6.3±1.5 8.2±1.0 6.6±1.0 7.2±0.5
1649 7891 30±9 35.±3 32.±6 34±0.5
1699 7939 18±5 11±2 20±4 13.4±1.5
1714 1953 42±9 38±5 57± 43.1±2.6
1744 7982 2.7±1 14.8±1.5 - 6.4±3.1
1748 7987 1.7±0.7 - - -
1763 8001 1.5±0.6 1.1±0.2 - 1.14±0.11
1771 8008 - 2.3±0.4 - -
1774 8011 3.6±1.2 2.4±0.8 - 2.77±0.46
1776 8013 0.8±0.3 - - -
1800 8036 - 0.18±0.03 - -
1811 8047 0.3±0.2 0.9±0.2 - 0.6±0.2
1829 8064 0.6±0.3 7.6±0.5 - 2.45±1.59
1833 8067 1.8±0.7 2.7±0.7 - 20.5±0.7
1899 8131 2.2±0.9 - - -
1998 8227 3.8±1.5 - - -
Table 2. Results of the measurements of γ ray angular distributions in the 25Mg(p, γ)26Al reaction
Ep, keV E∗
i → E∗
f keV a2 a4 a6 χ2
min δ
953 722→2069 -0.21±0.03 -0.11±0.03 0.03±0.04 0.7 0.24±0.02
1375 7628→4205 -0.03±0.03 -0.08±0.04 0.03±0.05 0.5 0.22±0.05
1587 7832→0 0.28±0.08 -0.24±0.09 0.07±0.09 0.6 -0.39±0.07
1649 7891→0 -0.13±0.03 -0.05±0.04 0.01±0.04 1.2 0.38±0.08
1699 7939→2069 0.28±0.05 -0.16±0.05 -0.01±0.05 0.4 -0.40±0.07
1714 7953→0 -0.11±0.01 -0.04±0.01 0.02±0.02 0.6 0.21±0.05
Further analysis of the angular distributions was
to find the spins of resonant states and γ ray multi-
polarity mixing ratios δ by minimizing the quantity
χ2:
χ2 =
∑
n
[
A0W
theor(θn)−W exp(θn)
∆W exp(θn)
]2
, (6)
where W theor(θ) =
∑
k Qkρk0Fk(J1 , J2 , L , δ)Pk is
the theoretical angular distribution of γ rays for the
transition between the initial and final states with
spins J1 and J2, W
exp(θ) and ∆W exp(θ) are experi-
mental data with the corresponding statistical errors,
A0 is a normalization constant, Qk is the coefficient
taking into account the finite size of the detector were
chosen from the tables, ρk0 is the element of the sta-
tistical tensor, and n is the number of experimental
points (angles).
The measurement results are illustrated in
Fig.2,a.
Fig.2. Decay of the resonance-like structure
from the 25Mg(p, γ)26Al reaction: a – resonance
strengths, b – reduced probabilities of γ transitions
to the ground state of 26Al, c – reduced probabilities
of γ transitions to the 2069 keV state, d – sum
of reduced transition probabilities to the states of
energies 3963...5726 keV
18
The obtained distribution of resonance strengths
made it easier to identify a resonance-like structure
(RLS) similar to those investigated earlier for the
nuclei of the sd shell [8, 9]. This the resonance-like
structures is of a complex structure; i.e, they con-
sisted of states belonging both to theM1 resonance of
the ground state and to the M1 resonance of excited
states [8, 9]. The obtained probability distributions of
magnetic dipole γ transitions have a resonance char-
acter and allow us to conclude that the resonances
that form the RLS belong to states of the M1 reso-
nance on the ground and excited states of the 26Al
nucleus (Figs.2,b, c, d).
The position of the center of gravity of the MDR
on the ground state in 26Al is equal to 7.92MeV .
Total strength MDR in 26Al is equal to 5.7MeV µ2
N .
The center of gravity of the MDR in 4N + np nu-
clei lies on the average 3MeV lower in the excitation
energy than that in 4N nuclei.
This difference can be explained by assuming the
existence of the neutron-proton pairing between the
odd neutron and proton being in the same orbit [9].
The analysis of the experimental data [9-17] al-
lowed us to obtain distributions of the M1-transition
probabilities for the ground state in the 22Na, 30P ,
34Cl nuclei (Fig.3).
5 6 7 8 9 10
0
2
4
5 6 7 8 9 100
2
4
5 6 7 8 9 10
0
2
5 6 7 8 9 10
0
2
4
22Na
26Al
B(M1), 10- 1
N
2
Q
p
Q
p
30P
Q
p
34Cl
E*, MeV
Q
p
Fig.3. Magnetic dipole resonance in odd-odd
(4N + np) sd-shell nuclei
The behavior of the MDR total strength in odd-
odd (4N + np) sd shell nuclei (Fig.4) differs from
that of the following from the Kurath sum rule. To
elucidate the reasons for this behavior of the total
strength of MDR in odd-odd nuclei of the sd shell,
further investigations are required.
3. CONCLUSIONS
In this paper, we studied the decay of the resonance-
like structure observed in the 25Mg(p, γ)26Al re-
action in the accelerated proton energy range
Ep = 1.4...2.0MeV . We also measured the exci-
tation function, spectra and angular distributions of
γ rays formed at the decay of the most intensive res-
onances with Ep = 953, 1375, 1587, 1649, 1699 and
1714 keV . From the analysis of the excitation func-
tion of this reaction and the angular distributions
of γ quanta, the resonance forces and the mixing
coefficients for the multipolarities of the γ radiation
are determined. The obtained probability distribu-
tions of magnetic dipole transitions on the ground
and excited states of the 26Al nucleus, which have a
resonance character. The MDR was identified on the
ground state in 26Al. The position of the center of
gravity of the MDR was found to be 7.92MeV . The
total strength of the MDR is found to be 5.7MeV
µ2
N .
15 20 25 30 35 40
1
10
100
34Cl
SM1
EW
, MeV
30P
26Al
22Na
32S
22Ne
18O
24Mg
30Si
40Ca
36Ar20Ne
34S
28Si
26Mg
16O
A
Fig.4. Dependence of the total MDR strength of
A for sd shell nuclei. The solid line is the Kurath
sum rule [6, 16]. Blacksquare – 4N nuclei (16O,
22Ne, 24Mg, 28Si, 32S, 36Ar, 40Ca) [3, 4, 14, 15];
� – 4N + 2n nuclei (18O, 22Ne, 26Mg, 30Si, 34S)
[3, 4, 15]; × – 4N + np nuclei (22Na, 26Al, 30P ,
34Cl) – our results
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ÐÅÇÎÍÀÍÑÍÎÏÎÄÎÁÍÀß ÑÒÐÓÊÒÓÐÀ, ÍÀÁËÞÄÀÅÌÀß Â ÐÅÀÊÖÈÈ
25Mg(p, γ)26Al
À.Ñ.Êà÷àí, È.Â.Êóðãóç, Â.Ì.Ìèùåíêî, Ñ.Í.Óòåíêîâ
Èçó÷åí γ-ðàñïàä ðåçîíàíñíîïîäîáíîé ñòðóêòóðû (ÐÏÑ), íàáëþäàåìîé â ðåàêöèè 25Mg(p, γ)26Al â ðàé-
îíå ýíåðãèé âîçáóæäåíèÿ 7...9ÌýÂ. Ïðîâåäåíû èçìåðåíèÿ ôóíêöèè âîçáóæäåíèÿ äàííîé ðåàêöèè. Ñè-
ëû ðåçîíàíñíûõ ñîñòîÿíèé îïðåäåëåíû â èíòåðâàëå ýíåðãèé óñêîðåííûõ ïðîòîíîâ Ep = 1, 4...2, 0ÌýÂ.
Ïîëó÷åííûå ðàñïðåäåëåíèÿ ñèëû M1 ïåðåõîäîâ ìåæäó ðåçîíàíñíûìè ñîñòîÿíèÿìè è íèçêîëåæàùèìè
ñâÿçàííûìè â 26Al èìåþò ðåçîíàíñíûé õàðàêòåð. Ïîëîæåíèå öåíòðà òÿæåñòè ìàãíèòíîãî äèïîëüíîãî
ðåçîíàíñà (ÌÄÐ) íà îñíîâíîì ñîñòîÿíèè ðàâíî 7, 92ÌýÂ. Ïîëíàÿ ñèëà ÌÄÐ ðàâíà 5, 7ÌýÂ µ2
N .
ÐÅÇÎÍÀÍÑÍÎÏÎÄIÁÍÀ ÑÒÐÓÊÒÓÐÀ, ÙÎ ÑÏÎÑÒÅÐIÃÀ�ÒÜÑß Â ÐÅÀÊÖI�
25Mg(p, γ)26Al
Î.Ñ.Êà÷àí, I.Â.Êóðãóç, Â.Ì.Ìiùåíêî, Ñ.Ì.Óò¹íêîâ
Âèâ÷åíî γ-ðîçïàä ðåçîíàíñíîïîäiáíî¨ ñòðóêòóðè (ÐÏÑ), ùî ñïîñòåðiãà¹òüñÿ â ðåàêöi¨ 25Mg(p, γ)26Al
â ðàéîíi åíåðãié çáóäæåííÿ 7...9ÌåÂ. Ïðîâåäåíî âèìiðþâàííÿ ôóíêöi¨ çáóäæåííÿ äàíî¨ ðåàêöi¨. Ñèëè
ðåçîíàíñíèõ ñòàíiâ âèçíà÷åíi â iíòåðâàëi åíåðãié ïðèñêîðåíèõ ïðîòîíiâ Ep = 1, 4...2, 0ÌåÂ. Îòðèìàíi
ðîçïîäiëè ñèëè M1 ïåðåõîäiâ ìiæ ðåçîíàíñíèìè ñòàíàìè i íèçüêîëåæà÷èìè ïîâ'ÿçàíèìè â 26Al ìàþòü
ðåçîíàíñíèé õàðàêòåð. Ïîëîæåííÿ öåíòðà âàãè ìàãíiòíîãî äèïîëüíîãî ðåçîíàíñó (ÌÄÐ) íà îñíîâíîìó
ñòàíi äîðiâíþ¹ 7, 92ÌåÂ. Ïîâíà ñèëà ÌÄÐ äîðiâíþ¹ 5, 7Ìå µ2
N .
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