T = 32 states in 21Na as seen in the 20Ne(p, p)20Ne reaction

doi:10.1016/0375-9474(69)90092-X

Nuclear Physics A

Volume 137, Issue 3, 17 November 1969, Pages 545-560

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Abstract

The two lowest $T = 32$ states in ²¹Na have been observed as narrow scattering anomalies in ²⁰Ne(p, p)²⁰Ne, using a differentially-pumped gas target. The observed resonance energies are E_p = 6.872 ± 0.005 MeV and E_p = 7.128 ± 0.005 MeV corresponding to E_x = 8.973 ± 0.007 MeV and E_x = 9.217 ± 0.007 MeV in ²¹Na. No other narrow scattering anomaly was found in the proton laboratory energy range 6.76–7.33 MeV although six anomalies of width greater than 13 keV were seen. From an analysis of the data using single level dispersion theory the following parameters were extracted for the $T = 32$ states: for the 8.973 MeV state, $J^{π} = 52$ ⁺ (or $32^{+})$ , ⊥_{total < 1.2 keV}, ⊥_po = 0.10 ± 0.05 keV and, for the 9.217 MeV state, $j^{π} = if 12^{+}$ , ⊥_total = 2.3 ± 0. 5keV and ⊥_Po = 1.1 ± 0.3 keV.

References (17)

E.G. Adelberger et al.
Nucl. Phys.
(1969)
P. Horvat
Nucl. Phys.
(1964)
P. Kienle et al.
Nucl. Phys.
(1963)
D.C. Hensley
Phys. Lett.
(1968)
H. Feshbach
Nuclear spectroscopy
R. McPherson et al.
Can. J. Phys.
(1965)
J.C. Hardy et al.
Can. J. Phys.
(1965)
G.W. Butler et al.
Phys. Rev.
(1968)

There are more references available in the full text version of this article.

Cited by (18)

Nuclear Data Sheets for A = 21
2015, Nuclear Data Sheets
This evaluation of A = 21 has been updated from previous evaluations published in 2004Fi10, 1998En04, 1990En08, and 1978En02. Coverage includes properties of adopted levels and γ-rays, decay-scheme data (energies, intensities and placement of radiations), and cross reference entries. The following tables continue the tradition of showing the systematic relationships between levels in A = 21. Much of the new data in this evaluations were taken directly from the xundl database, compiled under the direction of Balraj Singh, McMaster University. The evaluator is particularly appreciative of the efforts of the xundl compilers.
Nuclear data sheets for A = 21
2004, Nuclear Data Sheets
This evaluation of A = 21 has been updated from previous evaluations published in Nucl. Phys. A 633 (1998), Nucl. Phys. A 521 (1990) 1, Nucl. Phys. A 529 (1991) 763, Nucl. Phys. A 564 (1993) 609, and Nucl. Phys. A 310 (1978) 1. Coverage includes properties of adopted levels and γ rays, decay-scheme data (energies, intensities and placement of radiations), and cross reference entries. The following tables continue the tradition of showing the systematic relationships between levels in A = 21.
Isospin-nonconserving particle decays in light nuclei
1992, Nuclear Physics, Section A
Isospin-nonconserving (INC) proton decays of nineteen $T = 32$ states in light nuclei (13 ⩽ A ⩽ 37) and alpha decays of three T = 2 states in 24 ⩽ A ⩽ 32 have been measured using high-energy resolution beams (FHWM about 600 eV) to produce excitation functions near these states for (p,p), (p,α) and (α,α) reactions. Resonances were analyzed using a helicity-amplitude formalism. The widths agree qualitatively with recent shell-model calculations that include isospin dependences in the hadronic part of the nucleon-nucleon force.
Isospin-forbidden proton and neutron emission in 1s-0d shell nuclei
1986, Physics Letters B
Spectroscopic amplitudes for the decay of $T = 32$ states in A = 4n + 1 nuclei (21 ⩽ A ⩽ 37) by proton and neutron emission to the T = 0 ground state of A = 4n daughter nuclei are calculated and compared with experiment. The calculations were performed in the framework of the shell model using the full or nearly full 1s-0d configuration space and an isospin-nonconserving interaction which reproduces experimental isotopic mass shifts. Contributions due to mixing with individual parent and daughter states are analyzed. The question of periodicity in A for these amplitudes is addressed.
20Ne(p, p<inf>0</inf>)20Ne and states of 21Na
1981, Nuclear Physics, Section A
Cross-section and analyzing power angular distributions have been measured for ²⁰Ne(p, p)²⁰Ne and ²⁰Ne(p, p₁)²⁰Ne^∗(1.63 MeV) for proton energies between 3.7 and 7.9 MeV. The measurements were made in 25 keV intervals between 3.7 and 4.4 MeV, and in 10 keV intervals over most of the region between 4.4 and 7.9 MeV. A phase-shift analysis of the elastic-scattering data has yielded resonance parameters for thirty-three levels in ²¹Na in the excitation energy region 6.0–9.9 MeV. Some of the strong even-parity resonances can be understood within the framework of the Nilsson model or the shell model. These resonances are also predicted by a macroscopic coupled-channels calculation involving rotational excitation of the 2⁺ and 4⁺ states of ²⁰Ne.
Energy levels of A = 21-44 nuclei (VI)
1978, Nuclear Physics, Section A
The experimentally determined properties of the A = 21–44 nuclei are compiled and evaluated, special emphasis being given to nuclear structure.
Separate tables for each of the nuclides reviewed give all available information about the following properties in this order: - excitation energies (E_x),
1. •
  - γ-ray branching ratios,
2. •
  - γ-ray mixing ratios (δ),
3. •
  - lifetimes (τ_m) or widths (Λ),
4. •
  - spin and parity (J^π) and isospin (T) assignments, and
5. •
  - any other data, on single-particle transfer, resonance levels, etc.
The “best” (or adopted) values for E_x, τ_m or Λ, J^π and T are summarized in a master table.
The review of each A-chain concludes with - a discussion of isospin multiplets,
1. •
  - a few remarks about the experimental situation, and
2. •
  - a compilation of references to relevant theoretical papers.

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^†: Present address: University of Adelaide, S.A. 5001, Australia.

^†: This work performed under the auspices of the U.S. Atomic Energy Commission.

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Nuclear Physics A

Abstract

References (17)

Nucl. Phys.

Nucl. Phys.

Nucl. Phys.

Phys. Lett.

Nuclear spectroscopy

Can. J. Phys.

Can. J. Phys.

Phys. Rev.

Cited by (18)

Nuclear Data Sheets for A = 21

Nuclear data sheets for A = 21

Isospin-nonconserving particle decays in light nuclei

Isospin-forbidden proton and neutron emission in 1s-0d shell nuclei

<sup>20</sup>Ne(p, p<inf>0</inf>)<sup>20</sup>Ne and states of <sup>21</sup>Na

Energy levels of A = 21-44 nuclei (VI)