The 9.2 and 24.3 keV nuclear transitions in
227
Th were studied in the
β
-
decay of
227
Ac employing the internal conversion electron spectroscopy. Values of
(
9244.6
±
0.8
)
and
(
24343.1
±
1.1
)
eV ...were determined for their energies. The 24.3 keV transition was found to be of the mixed (M1
+
E2) multipolarity with the spectroscopic admixture parameter
δ
2
(
E
2
/
M
1
)
=
(
0.0116
±
0.0004
)
. Energies of
(
24342.9
±
1.2
)
,
(
28613.3
±
1.7
)
, and
(
37860.2
±
2.0
)
eV were obtained respectively for the 24.3, 28.6, and 37.8 keV transitions in
227
Th by means of the gamma-ray spectroscopy. Natural atomic-level widths of
(
14.1
±
0.5
)
,
(
11.4
±
0.5
)
,
(
6.9
±
0.4
)
,
(
11.4
±
1.4
)
,
(
8.6
±
1.2
)
, and
(
6.0
±
0.7
)
eV for the M
1
-, M
2
-, M
3
-, N
1
-, N
2
-, and N
3
-subshells of thorium, respectively, were derived from conversion electron lines. The cross checking of the energy values of the 9.2, 15.1, and 24.3 keV nuclear transitions obtained by the ICES method is also given.
.
Using the internal conversion electron spectroscopy, the energy of the 15.1 keV
M
1
+
E
2
nuclear transition in
227
Th populated in the
β
-
decay of
227
Ac was determined to be
15098
.
6
±
1
.
0
...eV. This value is more accurate than the present accepted one by a factor of 200. The present uncertainty in the transition multipolarity was removed and it was found to be
M
1
+
E
2
with the admixture
|
δ
(
E
2
/
M
1
)
|
=
0
.
035
±
0
.
006
.
•The K, L1–3, M1–3 electron binding energies in Kr in the Pt bulk determined.•The K, L1–3, M1–3 electron binding energies in Kr in an evaporated Rb layer obtained.•The krypton K, L1–3, M1 atomic ...level widths determined for the both host matrices.•The Kr KL2L3(1D2) Auger transition energies measured for the both host matrices.•The KL2L3(1D2) energy difference between Rb and Kr in the Pt host measured.•Dirac–Fock calculations of the Kr KLL Auger transitions performed.
The low-energy electron spectra emitted in the radioactive decay of the 83Rb and 83Sr isotopes were measured with a combined electrostatic electron spectrometer. Radioactive sources used were prepared by ion implantation of 83Sr into a high purity polycrystalline platinum foil at 30keV and by vacuum-evaporation deposition of 83Rb on the same type of foil. From the measured conversion electron spectra, the electron binding energies (referenced to the Fermi level) for the K, L1, L2, L3, M1, M2, and M3 shell/subshells of krypton in the platinum host were determined to be 14316.4(12), 1914.3(9), 1720.3(9), 1667.6(9), 281.5(9), 209.6(13), and 201.2(15)eV, respectively, and those for the evaporated layer were observed to be lower by 0.7(1)eV. For both host matrices, values of 2.3(2), 4.6(2), 1.7(2), 1.3(2), and 3.2(3)eV were obtained for the krypton K, L1, L2, L3, and M1 natural atomic level widths, respectively. The absolute energies of 10838.5(9) and 10839.5(10)eV were measured for the KL2L3(1D2) Auger transition in krypton implanted in Pt and generated in the evaporated rubidium layer, respectively. A value of 601.0(8)eV was measured for the energy difference of the KL2L3(1D2) transitions in Rb and Kr in the Pt host. Multiconfiguration Dirac–Fock calculations of the krypton KLL transition energies and intensities were also performed.
•The KLL Auger electron spectra of Zr and Nb investigated in detail.•Energies, relative intensities, and natural widths of spectrum components determined.•Results of our ab initio multiconfiguration ...Dirac-Hartree-Fock calculations discussed.•An influence of the atomic structure effect on the Zr absolute energies found.•An impact of the relativistic effects on the KL1L2(3P0) transition intensity observed.
The KLL Auger electron spectra of Zr (Z = 40) and Nb (Z = 41) following respectively the electron capture (EC) decay of 90Nb and the de-excitation of the isomeric state of 91mNb were investigated in detail using a combined electrostatic electron spectrometer and radioactive sources prepared by surface sorption on a polycrystalline carbon substrate. For both elements, energies, relative intensities, and natural widths of all the nine well-resolved basic spectrum components were determined and compared with theoretical predictions and with results of previous measurement as well. Results of our ab initio multiconfiguration Dirac-Hartree-Fock calculations are discussed also in relation to the solid-state effect. Indications of an influence of the EC decay on the absolute energy of the KL2L3(1D2) transition (so-called atomic structure effect) in Zr were found. The effect of the retarded current-current interaction on the KL1L2(3P0) transition intensity was observed to be appreciable for the investigated elements in accordance with the prediction.
Experimental KLM+KLN Auger spectrum of Cu Inoyatov, A.Kh; Perevoshchikov, L.L.; Zhdanov, V.S. ...
Journal of electron spectroscopy and related phenomena,
August 2013, Letnik:
189, Številka:
5-7
Journal Article
Recenzirano
•The KLM Auger spectrum of Cu was measured for the first time in detail.•Energies and relative intensities of nine resolved spectrum components were determined.•Semi-empirical KLM energy predictions ...and experiment agree mostly within 3σ with the exception of the transitions involving the M4,5 atomic subshells.•It was found that the KLM transition rates at Z=29 should be calculated relativistically in intermediate coupling scheme.
The KLM+KLN Auger electron spectrum of Cu (Z=29) emitted in the electron capture decay of radioactive 65Zn in a solid matrix was investigated for the first time using a combined electrostatic electron spectrometer adjusted to the 7eV instrumental resolution. Energies and relative intensities of nine resolved spectrum components were determined and compared with theoretical expectations. An agreement within 3σ was found between the semi-empirical predictions for the KLM transition energies by Larkins and the experimental data with the exception of the weak (KL2M4,5+KL2N1) and (KL3M4,5+KL3N1) lines where the differences reached 5σ. From a comparison of the measured relative KLM transition intensities with available theoretical results a conclusion was derived that calculations of the KLM transition rates at Z=29 should be based on intermediate coupling of angular momenta and take into account relativistic effects.
•The thulium L, M, N, O, and P subshell electron binding energies determined.•Five different matrices of the radioactive 169Yb atoms used in the investigation.•The greatest difference of 4.5±0.1eV in ...the average observed between the matrices.•The published N1, N3, and O2,3 values found to be higher by about 3eV.•Natural widths of the thulium K, L, M, N, and O subshells also determined.
The L1, L2, L3, M1, M2, N1, N3, O1, O2, O3, and P1 subshell electron binding energies (related to the Fermi level) in thulium generated by the electron capture decay of radioactive 169Yb atoms implanted at 30keV into polycrystalline platinum and aluminum foils and deposited by vacuum evaporation on surfaces of polycrystalline platinum, carbon, and aluminum foils were determined by the internal conversion electron spectroscopy. The greatest differences in the electron binding energies (4.5±0.1eV in the average without the P1 shell and 7.0±0.5eV for the P1 shell alone) were found between the matrices of the evaporated ytterbium layer on the aluminum foil and the bulk of the high purity polycrystalline platinum. The thulium electron binding energies in the matrices of the evaporated ytterbium layers on both the platinum and carbon foils and in the aluminum bulk were observed to be the same within the experimental uncertainties. The N1, N3, and O2,3 electron binding energies most frequently presented in data compilations were found to be higher by about 3eV. Natural widths of most of the K, L1, L2, L3, M1, M2, M3, N1, N3, and O1 subshells in Tm in the investigated matrices were also determined. No significant differences in the natural widths were found among the matrices. The results obtained demonstrate that the physicochemical surrounding of the radioactive atoms should be well defined and understandable for any type of electron calibration source particularly in the case of the super stable calibration 83Rb/83mKr electron sources for the KATRIN neutrino mass experiment.
•Eight different matrices (evaporated and implanted at 30keV) used.•The greatest average difference in the binding energies amounted to 3.1±0.1eV.•The presence of trivalent and divalent Sm ions found ...in some implanted samples.•No significant differences in Sm natural atomic level widths were observed.
Effects of the atomic environment on the L1, L2, L3, M1, M2, M3, and N1 electron binding energies in samarium generated in the electron capture decay of radioactive 149Eu were investigated by means of the internal conversion electron spectroscopy using the conversion electron spectrum of the 22.5keV M1+E2 nuclear transition in the daughter 149Sm. In this investigation, four pairs of 149Eu sources prepared by vacuum evaporation deposition and by ion implantation at 30keV with the use of four different source backing materials, namely polycrystalline carbon, aluminium, gadolinium and platinum foils, were employed. The greatest average difference of (3.1±0.1)eV in the L1, L2, L3, and M1 subshell electron binding energies was observed between the 149Eu sources prepared by ion implantation into the aluminium and platinum substrates. On the other hand, minimal differences in the electron binding energies were generally found between samarium generated in the evaporated layer and in the bulk for the individual investigated source backings with the exception of the gadolinium foil. A doublet structure of all investigated conversion electron lines with the average values of 8.1±0.2eV and 1.5±0.1 for the separation energy and the intensity ratio of the low-energy to high-energy components, respectively, was observed for the 149Eu sources prepared by ion implantation into the aluminium and carbon foils. This structure was presumably caused by the presence of both the trivalent and divalent Sm ions in the sources. No significant differences in natural widths of the L1, L2, L3, M1, M2, and M3 samarium atomic levels among the investigated matrices were observed with the exception of the source prepared by the implantation of the 149Eu ions into the platinum foil for which the determined values for all investigated subshells were apparently higher.
.
Using internal conversion electron spectroscopy, improved energy 21 541.5±0.5 eV was determined for the 21.5keV
M
1 +
E
2 nuclear transition in
151
Eu populated in the electron capture decay of
151
...Gd . This value was found to agree well with the present adopted value but is much more accurate. A value of 0.0305±0.0011 derived for the
E
2 admixture parameter
from the measured conversion electron line intensities corresponds to the present adopted value. A possible effect of nuclear structure on the multipolarity of the 21.5 keV transition was also investigated.
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