Spin and parity assignments for 17O levels from the 13C(α, n)16Og.s. reaction

doi:10.1016/0375-9474(70)90275-7

Nuclear Physics A

Volume 147, Issue 2, 25 May 1970, Pages 423-448

https://doi.org/10.1016/0375-9474(70)90275-7 Get rights and content

Abstract

The excitation function at 0° from E_α = 4.5 MeV to 10.5 MeV (lab) and fourteen angular distributions from 0° to 170° over the energy range E_α = 4.995 to 8.657 MeV (lab) have been measured for the ¹³C(α, n₀)¹⁶O reaction proceeding by way of intermediate ¹⁷O states with excitation energies from 9.8 to 14.4 MeV. After normalization to an absolute cross-section scale, the angular distributions were analyzed, using two-level compound-nucleus theory with provision for the coherent mixing of any two ¹⁷O states having spin values up to $92$ , of either parity, and therefrom fourteen sets of spin-parity assignments were adduced for levels in ¹⁷O at high excitation (10 to 13 MeV) corresponding to resonances in the excitation function, in conformity with previous tentative, approximate, assignments.

References (46)

G.W. Kerr et al.
Nucl. Phys.
(1968)
M. Soga
Nucl. Phys.
(1966)
C. Détraz et al.
Phys. Lett.
(1969)
T.K. Alexander et al.
Nucl. Instr.
(1961)
L. Cranberg et al.
Nucl. Instr.
(1961)
E. Sheldon et al.
Computer Phys. Comm.
(1969)
D. Wilmore et al.
Nucl. Phys.
(1964)
F.P. Brady et al.
Nucl. Phys.
(1967)
F. Perey et al.
Nucl. Phys.
(1962)
C. Quesne
Nucl. Phys.
(1966)

G.E. Brown et al.

Nucl. Phys.

(1966)

J. Birkholz et al.

Phys. Lett.

(1968)

J.M. Morris et al.

Nucl. Instr.

(1966)

W.L. Baker

Ph.D. Thesis

(1969)

T.W. Bonner et al.

Phys. Rev.

(1956)

R.L. Becker et al.

Phys. Rev.

(1956)

M.G. Rushbridge

J.P. Schiffer et al.

Phys. Rev.

(1957)

R.B. Walton et al.

Phys. Rev.

(1957)

T.W. Barnes et al.

Phys. Rev.

(1965)

K.K. Sekharan et al.

Phys. Rev.

(1967)

V.K. Deshpande et al.

University of Rochester Report UR-875-8

(1964)

R.B. Owen

Nucleonics

(1959)

Cited by (19)

Neutron yield and energy spectrum of 13C(alpha,n)16O reaction in liquid scintillator of KamLAND: A Nedis-2m simulation
2021, Nuclear Engineering and Technology
Citation Excerpt :
To demonstrate the contribution of (α,n) neutrons originating from the excited levels and to show the generation of non-monoenergetic neutrons in a 22 μg/cm2-thick target, a Nedis-2m calculation example is presented for individual alpha particle energies, Eαi, on targets made of carbon, 99% enriched in 13C. The data on the angular distributions of (α,n) neutrons in the center-of-mass system were taken from Refs. [19,20], whilst the atomic stopping power data of alpha particles, in units of 10−15 eV cm2·atom−1, were obtained using the equations taken from Ref. [21]. Here it is assumed that the liquid scintillator of the setup is a thick CH1.87 hydrocarbon target with a density of ~0.78 g/cm3 [22], and the energy spectrum of neutrons was obtained for 210Po alpha particles with an energy of 5.304 MeV.
The ¹³C (α,n)¹⁶O reaction cross-section is important data for nuclear physics, astrophysical, and neutrino physics experiments, however, they exhibit uncertainties due to the discrepancies in the experimental data. In this study, using the Nedis-2m program code, the energy spectrum of α-induced neutrons in a thin carbon target was calculated and the corresponding reaction cross-section was refined in the alpha particle energy range of 5–8 MeV. The results were used to calculate the intensity and energy spectrum of background neutrons produced in the liquid scintillator of KamLAND. The results will be useful in a variety of astrophysical and neutrino experiments especially those based on LS or Gd-LS detectors.
Spin and parity assignments for 23Na levels from the 19F(α, p)22Ne reaction
1976, Nuclear Physics, Section A
Resonances were found in the 120° and 160° excitation functions for the ¹⁹F(α, p_o)²²Ne reaction between E = 2.5 and 5.0 MeV corresponding to ²³Na levels at excitation energies between 12.56 and 14.51 MeV. Twenty-one on-resonance angular distributions were analysed with single-level and two-level theory to extract ²³Na spin and parity information. The results of an earlier experiment were analysed by the same procedure, extending the diagnostics down to a ²³Na excitation energy of 11.55 MeV. The analysis incorporated an optical potential for the α-particle consistent with previous channel-spin- $12$ reaction studies and α-induced reaction data.
Spin and parity assignments for 33S levels from the 29Si(α, n)32S reaction
1975, Nuclear Physics, Section A
In ²⁹Si(α, n₀)³²S excitation functions measured at 0° and 160° between E_α = 3.5–5.5 MeV, sharp resonances have been located corresponding to ³³S levels at excitation energies between 10.19 and 11.98 MeV. Forty-two on-resonance angular distributions were measured and normalized to an absolute cross-section scale. Spin $12$ , $32$ , $52$ and $72$ states in ³³S have been identified via the characteristic shape of the single-level angular distributions. An analysis employing both single-level and coherently admixed two-level theory which is sensitive to both shape and magnitude of the on-resonance distributions has furnished spin and parity assignments to single- and twin-level resonances. An optical potential of the Woods-Saxon volume-absorption type has been deduced for α-particles providing agreement with the ¹³C, ¹⁹F, ²⁹Si and ³¹P α-particle scattering and alpha-nucleon data.
"MIA", a Fortran-IV program for making spin and parity assignments to high-lying single and coherent twin nuclear levels from (Alpha, Nucleon) angular distributions in on-resonance, compound-nuclear, channel-spin- 1 2 reactions
1974, Computer Physics Communications
Computation of total, differential and double-differential cross sections for compound nuclear reactions of the type (a, b), (a, bσ) and (a, bσ-σ). (III) Fortran translations of the algol programs 'Mandy' and 'Barbara'
1971, Computer Physics Communications
Title of program: (32 characters maximum): MANDYF Catalogue number: ABOJ Program obtainable from: CPC Program Library Queen's University of Belfast, N. Ireland (see application form in this issue) Computer for which the program is designed and others upon which it is operable Computer Digital PDP-10 (or PDP-9 with 32K core memory) Installation: PDP-10 at Digital Equipment Corp., Maynard, Mass., USA PDP-9 at Nuclear Center, Lowell Technological Institute, Lowell, Mass., USA Operating system or monitor under which the program is executed: PDP-10 Monitor System or PDP-9 Advanced Software System Programming languages used: FORTRAN-IV High speed store required: 14 K words. No. of bits in word: 36 Is the program overlaid? No No. of magnetic tapes required: None What other peripherals are used? Disk or Dectape (optional); Card Reader; Line Printer No. of cards in combined program and test deck: 1 302 Card punching code: IBM 026 Reference to other published version of this program: Catalogue number: ABOA; Title: MANDY; Ref. in CPC: 1 (1969) 35
Proton polarization in 16O(p, p)16O and states in 17F*
1971, Nuclear Physics, Section A
The proton polarization in ¹⁶O(p, p)¹⁶O has been measured for laboratory energies between 8.5 and 12.7 MeV with the polarized proton beam from the Notre Dame polarized ion source. Measurements were made for 12 or more angles at 28 energies. In addition, excitation functions of polarization were measured at several angles between 10.2 and 12.0 MeV. A phaseshift analysis was made of both the polarization and published cross-section data. The energy dependence of the complex phase shifts yielded assignments of $J^{gh} = 32^{+}$ , $72^{−}$ , $32^{−}$ and $92^{+}$ to the ¹⁷F levels at E_x = 8.77, 8.97, 9.27 and 9.91 MeV, respectively. The data above 10.0 MeV confirm the assignments made by Toutenhoofd for the resonances near 10.5 and 12.5 MeV.

View all citing articles on Scopus

^‡: Work supported by the National Science Foundation.

^†: Present address: Fort Sill, Oklahoma.

^††: Present address: Dept. of Physics, Lowell Technological Institute, Lowell, Mass.

^†††: N.S.F. Senior Foreign Scientist Fellow, on leave from the Laboratorium für Kernphysik, Eidg. Technische Hochscule, Zürich, Switzerland. Now at the Center for Nuclear Studies, University Texas, Austin, Texas.

View full text

Article preview

Nuclear Physics A

Abstract

References (46)

Nucl. Phys.

Nucl. Phys.

Phys. Lett.

Nucl. Instr.

Nucl. Instr.

Computer Phys. Comm.

Nucl. Phys.

Nucl. Phys.

Nucl. Phys.

Nucl. Phys.

Nucl. Phys.

Phys. Lett.

Nucl. Instr.

Ph.D. Thesis

Phys. Rev.

Phys. Rev.

Phys. Rev.

Phys. Rev.

Phys. Rev.

Phys. Rev.

University of Rochester Report UR-875-8

Nucleonics

Cited by (19)

Neutron yield and energy spectrum of <sup>13</sup>C(alpha,n)<sup>16</sup>O reaction in liquid scintillator of KamLAND: A Nedis-2m simulation

Spin and parity assignments for <sup>23</sup>Na levels from the <sup>19</sup>F(α, p)<sup>22</sup>Ne reaction

Spin and parity assignments for <sup>33</sup>S levels from the <sup>29</sup>Si(α, n)<sup>32</sup>S reaction

"MIA", a Fortran-IV program for making spin and parity assignments to high-lying single and coherent twin nuclear levels from (Alpha, Nucleon) angular distributions in on-resonance, compound-nuclear, channel-spin- 1 2 reactions

Computation of total, differential and double-differential cross sections for compound nuclear reactions of the type (a, b), (a, bσ) and (a, bσ-σ). (III) Fortran translations of the algol programs 'Mandy' and 'Barbara'

Proton polarization in <sup>16</sup>O(p, p)<sup>16</sup>O and states in <sup>17</sup>F<sup>*</sup>