Spectroscopic investigations of the decay 223Ra → 219Rn

doi:10.1016/0375-9474(74)90412-6

Nuclear Physics A

Volume 223, Issue 2, 29 April 1974, Pages 234-252

https://doi.org/10.1016/0375-9474(74)90412-6 Get rights and content

Abstract

Internal conversion electron spectra of the transitions 4.4 keV, 10.0 keV, 14.4 keV, and 324.1 keV in the decay ²²³Ra → ²¹⁹Rn were measured. E2/M1 mixing ratios of these γ-transitions were deduced from conversion electron intensity ratios: δ² = 3.8(4) · 10⁻³, 2.35(18) · 10⁻³, 12.85(36) · 10⁻³, 0.23(3). The half-lives of the 4.4 keV and 14.4 keV levels were determined as $T_{12} = 15.4(1.3)$ nsec and 0.875(30) nsec. Reduced transition probabilities were calculated and compared to the Weisskopf estimates. αγ angular correlation measurements of the transitions 269.6 keV, 324.1 keV, and 338.6 keV and an αγ linear polarization measurement of the 269.6 keV transition were performed for spin determination. We assign $I = 72$ to the ²¹⁹Rn ground state and $I = 52$ or $92$ to the 269.6 keV state. All other low excitations including the 338.6 keV level have spins $I = 52$ , $72$ , or $92$ . The spins of the states 158.7 keV and 14.4 keV are equal. The ²²³Ra ground state spin is $I = 72$ or $92$ . The possibility of an interpretation of the transitional nucleus ²¹⁹Rn in the frame of the collective model is discussed.

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Cited by (9)

Nuclear Data Sheets for A=219
2021, Nuclear Data Sheets
Evaluated experimental structure and decay data are presented for 12 known nuclides of mass 219 (Pb, Bi, Po, At, Rn, Fr, Ra, Ac, Th, Pa, U, Np). Recommended values are given for level parameters, γ and α radiations, and other spectroscopic information. No excited states are known in ²¹⁹Bi, ²¹⁹Po, ²¹⁹Pa, ²¹⁹U and ²¹⁹Np. Except for isotopic identification, no information about its half-life or decay characteristics is available for ²¹⁹Pb. For ²¹⁹Po, several γ rays have been reported from the decay of ²¹⁹Bi β⁻ decay, but no level scheme has been proposed. For ²¹⁹At, only four excited states are known from α decay of ²²³Fr. For ²¹⁹Rn and ²¹⁹Fr, only the low-spin states are known from α decays of ²²³Ra and ²²³Ac, respectively. For ²¹⁹Ra, ²¹⁹Ac and ²¹⁹Th, mainly the data for high-spin states are available from in-beam γ-ray studies. For ²¹⁹Ra, high-spin data are available from 2017He15, 1992Wi02 and 1987Co36, but evaluators find significant differences in relative photon branchings between the three studies. Detailed comments are given in the Adopted dataset for this nuclide. Half-lives of excited states are known only for seven levels in ²¹⁹Rn, thus there is a general lack of knowledge about γ-ray transition probabilities. This work supersedes data in the previous evaluations of A=219 published by 2001Br31, 1992Br10 and 1977Ma30.
Nuclear data sheets for A = 215, 219, 233, 227, 231
2001, Nuclear Data Sheets
The evaluator presents in this publication spectroscopic data and level schemes from radioactive decay and nuclear reaction studies for all nuclei with mass numbers A=215, 219, 223, 227, and 231. Nuclei with mass number A=215 have spherical shape, and their nuclear structure have been interpreted in terms of the shell model. Nuclei with mass number A=219 belong to a transitional region with spherical, quadrupole, and possibly octupole deformations; those with mass numbers A=223 and 227 belong to a newly studied region of coexisting quadrupole with possible octupole deformations; and nuclei with mass number A=231 essentially have quadrupole deformation. Highlights of this publication are given below: A recent study of the ²⁰⁶Pb(¹³C,4nγ) reaction (1998St24) has extended up to Jπ=61/2+ the previously known level scheme from ²⁰⁸Pb(¹³C,6nγ) (1988Fu10,1983Lo16). This study has provided a new interpretation for all the spectroscopic data above the 2247--keV (Jπ=29/2--) level in ²¹⁵Ra. A new isotope, ²¹⁹U (42 μs), which was identified with the recoil separator VASSILISSA (1994Ye08,1994AnZY,1993An07), has been included in this evaluation. The first ²²³Rn β-- decay scheme (1992Ku03) and a significantly improved measurement of ²²⁷Ac α decay (1995Sh03) are presented here. A level scheme of ²²³Fr has been constructed on the basis of these studies, where most of the levels below 600 keV have been assigned to parity doublet bands and interpreted in terms of the reflection--asymmetric rotor model. This evaluation includes the first level structures of ²²⁷Fr and ²²⁷Th. Levels in ²²⁷Fr are from ²²⁷Rn β-- decay (1997Ku20); those in ²²⁷Th, are from ²³¹U α decay, from ²²⁷Pa electron--capture decay, and from ²²⁶Ra(α,3nγ) (1997Mu08,1995Li04,1998Ma83). A study of the β-- decay of a mass--separated source of ²³¹Fr has produced the first level scheme of ²³¹Ra (2001Fr05). The only published data (1994Br36,1996Le01) on the electron--capture decay of ²³¹U have provided much information on the level structure of ²³¹Pa. Studies on ²³²Th(p,2nγ) and Coulomb Excitation of ²³¹Pa (1996Le01,1999Wu05), which have complemented the existing spectroscopic data from these reactions, have suggested the possibility of weak octupole correlations in ²³¹Pa. A new isotope of plutonium, ²³¹Pu (1999La14), has been included in this evaluation.
Nuclear data sheets for A = 215,219,223,227
1992, Nuclear Data Sheets
This publication presents evaluated spectroscopic data and corresponding level schemes from radioactive decay and nuclear reaction studies for all nuclei with mass numbers A=215, 219, 223, and 227.
Nuclei with mass number A=215 have spherical shape, and their nuclear structure has been interpreted in terms of the shell model. Nuclei with mass number A=219 belong to a transitional region, with spherical, quadrupole, and possibly, octupole deformations, and those with mass numbers A=223 and 227, to newly studied regions of deformations (pure quadrupole coexisting with possible octupole). Because deformations are small in these regions, nuclear states are no longer fully characterized by single Nilsson orbitals. This terminology, however, is used throughout this evaluation to label states rather than to accurately describe their nature.
Highlights of this publication include the emission of ¹⁴C by ²²³Ra, discovered by Rose and Jones (84Ro30), and its fine structure, measured by Brillard et al. (89Br34). This constitutes a new mode of decay and provides additional arguments for configuration assignments. They further include the first set of nuclear levels in ²¹⁵Fr, ²¹⁵Ra, and ²¹⁵Ac, determined from in—beam γ-ray spectroscopic measurements.
Two major publications have been extensively used in this evaluation: the theoretical paper “Reflection—asymmetric Rotor Model of Odd—A ≈219–229 Nuclei” by Leander and Chen (88Le13), which presents a calculation of single—particle state properties by the coupling of shell—model states to a reflection—asymmetric rotor core; and the review paper “Intrinsic States of Deformed Odd—A Nuclei in the Mass Regions (151≤A≤193) and (A≥221)” by Jain et al. (90Ja11), which gives the systematics and assignments of single—particle states in such mass regions.
These evaluations for A=215, 219, 223, and 227 supersede the earlier ones by C. Maples: 77Ma29, Nuclear Data Sheets 22, 207 (1977); 77Ma30, Nuclear Data Sheets 22, 223 (1977); 77Ma31, Nuclear Data Sheets 22, 243 (1977); and 77Ma32, Nuclear Data Sheets 22, 275 (1977).
Nuclear data sheets for A = 223
1977, Nuclear Data Sheets
Available information on decay characteristics and level structure for all nuclei with A = 223 has been examined. A summary and evaluation of experimental data, including adopted values and comparison with theory are presented. The individual level schemes are discussed, and coments pertaining to adopted spin and parity assignments and to gamma-ray multipolarities are given. Any apparent discrepancies and inconsistencies are pointed out.
Much of the level information in the A = 223 mass chain is obtained from the α-decay and the A = 227 parent nuclei. While a summary of these results is reflected in both the level schemes and in discussions under “Level Properties” and “Gamma-Ray Properties”, the actual data are presented under the respective A = 227 parent.
Decay energies and separation energies have been taken systematically from the 1977 Mass Adjustment (76WaBo, 77Wa08). Detailed comparison has been made between the adopted α-energies and the input values to the Mass Adjustment.
Multipole mixing ratios and substate populations in Rn-219
2016, Journal of Physics G: Nuclear and Particle Physics
Spectroscopy of actinide and transactinide nuclei
2011, Radiochimica Acta

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^†: Present address: Department of Physics, University of Manitoba, Winnipeg, Canada.

^††: Present address: Lawrence Radiation Laboratory, University of California, Berkeley, CAlif. 94270, USA.

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Spectroscopic investigations of the decay 223Ra → 219Rn

Abstract

Nucl. Phys.

Nucl. Phys.

Nucl. Phys.

Nucl. Phys.

Nucl. Instr.

Ark. Fys.

Nucl. Phys.

Mat. Fys. Med. Dan. Vid. Selsk.

Thesis, UCRL-3877

Nukleonik

Spectroscopic investigations of the decay $^{223} Ra →^{219} Rn$