1
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Lopez-Saavedra E, Almaraz-Calderon S, Asher BW, Baby LT, Gerken N, Hanselman K, Kemper KW, Kuchera AN, Morelock AB, Perello JF, Temanson ES, Volya A, Wiedenhöver I. Observation of a Near-Threshold Proton Resonance in ^{11}B. Phys Rev Lett 2022; 129:012502. [PMID: 35841540 DOI: 10.1103/physrevlett.129.012502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 04/26/2022] [Accepted: 06/01/2022] [Indexed: 06/15/2023]
Abstract
A near-threshold proton resonance in ^{11}B at E_{ex}=11.44±0.04 MeV is observed via the reaction ^{10}Be(d,n)^{11}Be→^{10}Be+p in inverse kinematics, measured with a beam of the radioactive isotope ^{10}Be. The resonance energy at E_{res}=211(40) keV is consistent with a proton signal observed by Ayyad et al. in the β-delayed proton decay of ^{11}Be. By comparison to a distorted wave Born approximation calculation, a 0.27(6) spectroscopic factor is extracted and a tentative (ℓ=0) character is assigned for this resonance. The significant cross section in the proton-transfer (d,n) reaction, as well as the observation of its proton-decay signal, point to the threshold-resonance character of this state. The position of this state, its structure, and strong coupling to the s-wave continuum represent an ideal case to study quantum near-threshold many-body dynamics of unstable states. The presence of this state is an important step toward understanding the excessively large beta-delayed proton-decay branch of ^{11}Be.
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Affiliation(s)
- E Lopez-Saavedra
- Department of Physics, Florida State University, Tallahassee, Florida 32306, USA
| | - S Almaraz-Calderon
- Department of Physics, Florida State University, Tallahassee, Florida 32306, USA
| | - B W Asher
- Department of Physics, Florida State University, Tallahassee, Florida 32306, USA
| | - L T Baby
- Department of Physics, Florida State University, Tallahassee, Florida 32306, USA
| | - N Gerken
- Department of Physics, Florida State University, Tallahassee, Florida 32306, USA
| | - K Hanselman
- Department of Physics, Florida State University, Tallahassee, Florida 32306, USA
| | - K W Kemper
- Department of Physics, Florida State University, Tallahassee, Florida 32306, USA
| | - A N Kuchera
- Department of Physics, Davidson College, Davidson, North Carolina 28035, USA
| | - A B Morelock
- Department of Physics, Florida State University, Tallahassee, Florida 32306, USA
| | - J F Perello
- Department of Physics, Florida State University, Tallahassee, Florida 32306, USA
| | - E S Temanson
- Department of Physics, Florida State University, Tallahassee, Florida 32306, USA
| | - A Volya
- Department of Physics, Florida State University, Tallahassee, Florida 32306, USA
| | - I Wiedenhöver
- Department of Physics, Florida State University, Tallahassee, Florida 32306, USA
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2
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Rijal N, Wiedenhöver I, Blackmon JC, Anastasiou M, Baby LT, Caussyn DD, Höflich P, Kemper KW, Koshchiy E, Rogachev GV. Erratum: Measurement of d+^{7}Be Cross Sections for Big-Bang Nucleosynthesis [Phys. Rev. Lett. 122, 182701 (2019)]. Phys Rev Lett 2019; 123:239902. [PMID: 31868430 DOI: 10.1103/physrevlett.123.239902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Indexed: 06/10/2023]
Abstract
This corrects the article DOI: 10.1103/PhysRevLett.122.182701.
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3
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Gade A, Brown BA, Tostevin JA, Bazin D, Bender PC, Campbell CM, Crawford HL, Elman B, Kemper KW, Longfellow B, Lunderberg E, Rhodes D, Weisshaar D. Is the Structure of ^{42}Si Understood? Phys Rev Lett 2019; 122:222501. [PMID: 31283300 DOI: 10.1103/physrevlett.122.222501] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 04/23/2019] [Indexed: 06/09/2023]
Abstract
A more detailed test of the implementation of nuclear forces that drive shell evolution in the pivotal nucleus ^{42}Si-going beyond earlier comparisons of excited-state energies-is important. The two leading shell-model effective interactions, SDPF-MU and SDPF-U-Si, both of which reproduce the low-lying ^{42}Si(2_{1}^{+}) energy, but whose predictions for other observables differ significantly, are interrogated by the population of states in neutron-rich ^{42}Si with a one-proton removal reaction from ^{43}P projectiles at 81 MeV/nucleon. The measured cross sections to the individual ^{42}Si final states are compared to calculations that combine eikonal reaction dynamics with these shell-model nuclear structure overlaps. The differences in the two shell-model descriptions are examined and linked to predicted low-lying excited 0^{+} states and shape coexistence. Based on the present data, which are in better agreement with the SDPF-MU calculations, the state observed at 2150(13) keV in ^{42}Si is proposed to be the (0_{2}^{+}) level.
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Affiliation(s)
- A Gade
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - B A Brown
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - J A Tostevin
- Department of Physics, University of Surrey, Guildford, Surrey GU2 7XH, United Kingdom
| | - D Bazin
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - P C Bender
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
| | - C M Campbell
- Nuclear Science Division, Lawrence Berkeley National Laboratory, California 94720, USA
| | - H L Crawford
- Nuclear Science Division, Lawrence Berkeley National Laboratory, California 94720, USA
| | - B Elman
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - K W Kemper
- Department of Physics, Florida State University, Tallahassee, Florida 32306, USA
| | - B Longfellow
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - E Lunderberg
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - D Rhodes
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - D Weisshaar
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
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4
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Rijal N, Wiedenhöver I, Blackmon JC, Anastasiou M, Baby LT, Caussyn DD, Höflich P, Kemper KW, Koshchiy E, Rogachev GV. Measurement of d+^{7}Be Cross Sections for Big-Bang Nucleosynthesis. Phys Rev Lett 2019; 122:182701. [PMID: 31144906 DOI: 10.1103/physrevlett.122.182701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 12/03/2018] [Indexed: 06/09/2023]
Abstract
The cross sections of nuclear reactions between the radioisotope ^{7}Be and deuterium, a possible mechanism of reducing the production of mass-7 nuclides in big-bang nucleosynthesis, were measured at center-of-mass energies between 0.2 and 1.5 MeV. The measured cross sections are dominated by the (d,α) reaction channel, towards which prior experiments were mostly insensitive. A new resonance at 0.36(5) MeV with a strength of ωγ=1.7(5) keV was observed inside the relevant Gamow window. Calculations of nucleosynthesis outcomes based on the experimental cross section show that the resonance reduces the predicted abundance of primordial ^{7}Li, but not sufficiently to solve the primordial lithium problem.
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Affiliation(s)
- N Rijal
- Physics Department, Florida State University, Tallahassee, Florida 32306, USA
| | - I Wiedenhöver
- Physics Department, Florida State University, Tallahassee, Florida 32306, USA
| | - J C Blackmon
- Department of Physics and Astronomy, Louisiana State University, Baton Rouge, Louisiana 70803, USA
| | - M Anastasiou
- Physics Department, Florida State University, Tallahassee, Florida 32306, USA
| | - L T Baby
- Physics Department, Florida State University, Tallahassee, Florida 32306, USA
| | - D D Caussyn
- Physics Department, Florida State University, Tallahassee, Florida 32306, USA
| | - P Höflich
- Physics Department, Florida State University, Tallahassee, Florida 32306, USA
| | - K W Kemper
- Physics Department, Florida State University, Tallahassee, Florida 32306, USA
| | - E Koshchiy
- Cyclotron Institute, Texas A&M University, College Station, Texas 77843, USA
| | - G V Rogachev
- Cyclotron Institute, Texas A&M University, College Station, Texas 77843, USA
- Department of Physics & Astronomy, Texas A&M University, College Station, Texas 77843, USA
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5
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Avila ML, Rogachev GV, Koshchiy E, Baby LT, Belarge J, Kemper KW, Kuchera AN, Mukhamedzhanov AM, Santiago-Gonzalez D, Uberseder E. Constraining the 6.05 MeV 0+ and 6.13 MeV 3- cascade transitions in the 12C(α,γ)16O reaction using the asymptotic normalization coefficients. Phys Rev Lett 2015; 114:071101. [PMID: 25763945 DOI: 10.1103/physrevlett.114.071101] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Indexed: 06/04/2023]
Abstract
The 12C(α,γ)^16O reaction plays a fundamental role in astrophysics and needs to be known with accuracy better than 10%. Cascade γ transitions through the excited states of 16 O are contributing to the uncertainty. We constrained the contribution of the 0+ (6.05 MeV) and 3- (6.13 MeV) cascade transitions by measuring the asymptotic normalization coefficients for these states using the α-transfer reaction 6 Li(12C,d)^16O at sub-Coulomb energy. The contribution of the 0+ and 3- cascade transitions at 300 keV is found to be 1.96 ± 0.3 and 0.12 ± 0.04 keV b for destructive interference of the direct and resonance capture and 4.36 ± 0.45 and 1.44 ± 0.12 keV b for constructive interference, respectively. The combined contribution of the 0+ and 3- cascade transitions to the 12C(α,γ)16O reaction cross section at 300 keV does not exceed 4%. Significant uncertainties have been dramatically reduced.
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Affiliation(s)
- M L Avila
- Department of Physics, Florida State University, Tallahassee, Florida 32306, USA
| | - G V Rogachev
- Department of Physics & Astronomy and Cyclotron Institute, Texas A&M University, College Station, Texas 77843, USA
| | - E Koshchiy
- Department of Physics & Astronomy and Cyclotron Institute, Texas A&M University, College Station, Texas 77843, USA
| | - L T Baby
- Department of Physics, Florida State University, Tallahassee, Florida 32306, USA
| | - J Belarge
- Department of Physics, Florida State University, Tallahassee, Florida 32306, USA
| | - K W Kemper
- Department of Physics, Florida State University, Tallahassee, Florida 32306, USA
| | - A N Kuchera
- Department of Physics, Florida State University, Tallahassee, Florida 32306, USA
| | - A M Mukhamedzhanov
- Department of Physics & Astronomy and Cyclotron Institute, Texas A&M University, College Station, Texas 77843, USA
| | - D Santiago-Gonzalez
- Department of Physics, Florida State University, Tallahassee, Florida 32306, USA
| | - E Uberseder
- Department of Physics & Astronomy and Cyclotron Institute, Texas A&M University, College Station, Texas 77843, USA
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6
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Gade A, Adrich P, Bazin D, Bowen MD, Brown BA, Campbell CM, Cook JM, Ettenauer S, Glasmacher T, Kemper KW, McDaniel S, Obertelli A, Otsuka T, Ratkiewicz A, Siwek K, Terry JR, Tostevin JA, Utsuno Y, Weisshaar D. Spectroscopy of 36Mg: interplay of normal and intruder configurations at the neutron-rich boundary of the "island of inversion". Phys Rev Lett 2007; 99:072502. [PMID: 17930889 DOI: 10.1103/physrevlett.99.072502] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2007] [Indexed: 05/25/2023]
Abstract
We report on the first spectroscopy study of the very neutron-rich nucleus (36)(12)Mg24 using the direct two-proton knockout reaction 9Be(38Si,36Mg+gamma)X at 83 MeV/nucleon. The energy of the first excited 2+ state of 36Mg, E(2+(1)=660(6) keV, was measured. The magnitude of the partial cross sections to the ground state and the 2+(1) state is indicative of strong intruder admixtures in the lowest-lying states as suggested by Monte Carlo shell-model calculations.
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Affiliation(s)
- A Gade
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
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7
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Fortier S, Tryggestad E, Rich E, Beaumel D, Becheva E, Blumenfeld Y, Delaunay F, Drouart A, Fomichev A, Frascaria N, Gales S, Gaudefroy L, Gillibert A, Guillot J, Hammache F, Kemper KW, Khan E, Lapoux V, Lima V, Nalpas L, Obertelli A, Pollacco EC, Skaza F, Pramanik UD, Roussel-Chomaz P, Santonocito D, Scarpaci JA, Sorlin O, Stepantsov SV, Ter Akopian GM, Wolski R. Search for resonances in 4n, 7H and 9He via transfer reactions. ACTA ACUST UNITED AC 2007. [DOI: 10.1063/1.2746575] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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8
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Johnson ED, Rogachev GV, Mukhamedzhanov AM, Baby LT, Brown S, Cluff WT, Crisp AM, Diffenderfer E, Goldberg VZ, Green BW, Hinners T, Hoffman CR, Kemper KW, Momotyuk O, Peplowski P, Pipidis A, Reynolds R, Roeder BT. Astrophysical reaction rate for the neutron-generator reaction 13C(alpha,n)16O in asymptotic giant branch stars. Phys Rev Lett 2006; 97:192701. [PMID: 17155619 DOI: 10.1103/physrevlett.97.192701] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2006] [Indexed: 05/12/2023]
Abstract
The reaction 13C(alpha,n) is considered to be the main source of neutrons for the s process in asymptotic giant branch stars. At low energies, the cross section is dominated by the 1/2+ 6.356 MeV subthreshold resonance in (17)O whose contribution at stellar temperatures is uncertain by a factor of 10. In this work, we performed the most precise determination of the low-energy astrophysical S factor using the indirect asymptotic normalization (ANC) technique. The alpha-particle ANC for the subthreshold state has been measured using the sub-Coulomb alpha-transfer reaction ((6)Li,d). Using the determined ANC, we calculated S(0), which turns out to be an order of magnitude smaller than in the nuclear astrophysics compilation of reaction rates.
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Affiliation(s)
- E D Johnson
- Department of Physics, Florida State University, Tallahassee, FL 32306, USA
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9
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Gaudefroy L, Sorlin O, Beaumel D, Blumenfeld Y, Dombrádi Z, Fortier S, Franchoo S, Gélin M, Gibelin J, Grévy S, Hammache F, Ibrahim F, Kemper KW, Kratz KL, Lukyanov SM, Monrozeau C, Nalpas L, Nowacki F, Ostrowski AN, Otsuka T, Penionzhkevich YE, Piekarewicz J, Pollacco EC, Roussel-Chomaz P, Rich E, Scarpaci JA, St Laurent MG, Sohler D, Stanoiu M, Suzuki T, Tryggestad E, Verney D. Reduction of the spin-orbit splittings at the n = 28 shell closure. Phys Rev Lett 2006; 97:092501. [PMID: 17026356 DOI: 10.1103/physrevlett.97.092501] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2006] [Indexed: 05/12/2023]
Abstract
The N = 28 shell closure has been investigated via the 46Ar(d,p)47Ar transfer reaction in inverse kinematics. Energies and spectroscopic factors of the neutron p(3/2), p(1/2), and f(5/2) states in 47Ar were determined and compared to those of the 49Ca isotone. We deduced a reduction of the N = 28 gap by 330(90) keV and spin-orbit weakenings of approximately 10(2) and 45(10)% for the f and p states, respectively. Such large variations for the f and p spin-orbit splittings could be accounted for by the proton-neutron tensor force and by the density dependence of the spin-orbit interaction, respectively. This contrasts with the picture of the spin-orbit interaction as a surface term only.
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Affiliation(s)
- L Gaudefroy
- IPN, IN2P3-CNRS,F- 91406 Orsay Cedex, France
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10
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Becheva E, Blumenfeld Y, Khan E, Beaumel D, Daugas JM, Delaunay F, Demonchy CE, Drouart A, Fallot M, Gillibert A, Giot L, Grasso M, Keeley N, Kemper KW, Khoa DT, Lapoux V, Lima V, Musumarra A, Nalpas L, Pollacco EC, Roig O, Roussel-Chomaz P, Sauvestre JE, Scarpaci JA, Skaza F, Than HS. N = 14 shell closure in 22O viewed through a neutron sensitive probe. Phys Rev Lett 2006; 96:012501. [PMID: 16486448 DOI: 10.1103/physrevlett.96.012501] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2005] [Indexed: 05/06/2023]
Abstract
To investigate the behavior of the N = 14 neutron gap far from stability with a neutron-sensitive probe, proton elastic and 2(1)+ inelastic scattering angular distributions for the neutron-rich nucleus 22O were measured using the MUr à STrip detector array at the Grand Accélérateur National d'Ions Lourds facility. A deformation parameter beta(p,p') = 0.26 +/- 0.04 is obtained for the 2(1)+ state, much lower than in 20O, showing a weak neutron contribution to this state. A microscopic analysis was performed using matter and transition densities generated by continuum Skyrme-Hartree-Fock-Bogoliubov and quasiparticle random phase approximation calculations, respectively. The ratio of neutron to proton contributions to the 2(1)+ state is found close to the N/Z ratio, demonstrating a strong N = 14 shell closure in the vicinity of the neutron drip line.
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Affiliation(s)
- E Becheva
- Institut de Physique Nucléaire, IN2P3-CNRS, 91406 Orsay, France
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11
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Fridmann J, Wiedenhöver I, Gade A, Baby LT, Bazin D, Brown BA, Campbell CM, Cook JM, Cottle PD, Diffenderfer E, Dinca DC, Glasmacher T, Hansen PG, Kemper KW, Lecouey JL, Mueller WF, Olliver H, Rodriguez-Vieitez E, Terry JR, Tostevin JA, Yoneda K. ‘Magic’ nucleus 42Si. Nature 2005; 435:922-4. [PMID: 15959511 DOI: 10.1038/nature03619] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2005] [Accepted: 03/24/2005] [Indexed: 11/08/2022]
Abstract
Nuclear shell structures--the distribution of the quantum states of individual protons and neutrons--provide one of our most important guides for understanding the stability of atomic nuclei. Nuclei with 'magic numbers' of protons and/or neutrons (corresponding to closed shells of strongly bound nucleons) are particularly stable. Whether the major shell closures and magic numbers change in very neutron-rich nuclei (potentially causing shape deformations) is a fundamental, and at present open, question. A unique opportunity to study these shell effects is offered by the 42Si nucleus, which has 28 neutrons--a magic number in stable nuclei--and 14 protons. This nucleus has a 12-neutron excess over the heaviest stable silicon nuclide, and has only one neutron fewer than the heaviest silicon nuclide observed so far. Here we report measurements of 42Si and two neighbouring nuclei using a technique involving one- and two-nucleon knockout from beams of exotic nuclei. We present strong evidence for a well-developed proton subshell closure at Z = 14 (14 protons), the near degeneracy of two different (s(1/2) and d(3/2)) proton orbits in the vicinity of 42Si, and a nearly spherical shape for 42Si.
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Affiliation(s)
- J Fridmann
- Department of Physics, Florida State University, Tallahassee, Florida 32306-4350, USA
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12
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Wiedeking M, Tabor SL, Pavan J, Volya A, Aguilar AL, Calderin IJ, Campbell DB, Cluff WT, Diffenderfer E, Fridmann J, Hoffman CR, Kemper KW, Lee S, Riley MA, Roeder BT, Teal C, Tripathi V, Wiedenhöver I. p-sd Shell gap reduction in neutron-rich systems and cross-shell excitations in 20 O. Phys Rev Lett 2005; 94:132501. [PMID: 15903988 DOI: 10.1103/physrevlett.94.132501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2004] [Indexed: 05/02/2023]
Abstract
Excited states in 20O were populated in the reaction 10Be(14C,alpha) at Florida State University (FSU). Charged particles were detected with a particle telescope consisting of 4 annularly segmented Si surface barrier detectors and gamma radiation was detected with the FSU gamma detector array. Five new states were observed below 6 MeV from the alpha-gamma and alpha-gamma-gamma coincidence data. Shell model calculations suggest that most of the newly observed states are core-excited 1p-1h excitations across the N=Z=8 shell gap. Comparisons between experimental data and calculations for the neutron-rich O and F isotopes imply a steady reduction of the p-sd shell gap as neutrons are added.
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Affiliation(s)
- M Wiedeking
- Florida State University, Tallahassee, Florida 32306, USA
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13
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Gade A, Bazin D, Brown BA, Campbell CM, Church JA, Dinca DC, Enders J, Glasmacher T, Hansen PG, Hu Z, Kemper KW, Mueller WF, Olliver H, Perry BC, Riley LA, Roeder BT, Sherrill BM, Terry JR, Tostevin JA, Yurkewicz KL. Reduced occupancy of the deeply bound 0d(5/2) neutron state in 32Ar. Phys Rev Lett 2004; 93:042501. [PMID: 15323753 DOI: 10.1103/physrevlett.93.042501] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2004] [Indexed: 05/24/2023]
Abstract
The 9Be(32Ar, 31Ar)X reaction, leading to the 5/2+ ground state of a nucleus at the proton drip line, has a cross section of 10.4(13) mb at a beam energy of 65.1 MeV/nucleon. This translates into a spectroscopic factor that is only 24(3)% of that predicted by the many-body shell-model theory. We introduce refinements to the eikonal reaction theory used to extract the spectroscopic factor to clarify that this very strong reduction represents an effect of nuclear structure. We suggest that it reflects correlation effects linked to the high neutron separation energy (22.0 MeV) for this state.
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Affiliation(s)
- A Gade
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
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14
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Cottle PD, Hu Z, Pritychenko BV, Church JA, Fauerbach M, Glasmacher T, Ibbotson RW, Kemper KW, Riley LA, Scheit H, Steiner M. 0(+)(gs) --> 2(+)(1) excitations in the mirror nuclei 32Ar and 32Si. Phys Rev Lett 2002; 88:172502. [PMID: 12005747 DOI: 10.1103/physrevlett.88.172502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2002] [Indexed: 05/23/2023]
Abstract
We measured the strength of the 0(+)(gs)-->2(+)(1) excitations in the radioactive mirror nuclei 32Ar and 32Si using the techniques of intermediate-energy Coulomb excitation for 32Ar and inelastic proton scattering in inverse kinematics for 32Si. The 32Ar measurement, taken together with previously existing Coulomb excitation data for 32Si, yields the isoscalar and isovector multipole matrix elements for the 0(+)(1)-->2(+)(1) transition between T = 2 states in the A = 32 system. The proton scattering measurement for 32Si, when combined with the Coulomb excitation data for this nucleus, yields a ratio of neutron and proton matrix elements, M(n)/M(p), for 32Si.
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Affiliation(s)
- P D Cottle
- Department of Physics, Florida State University, Tallahassee, Florida 32306, USA
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15
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Gay DL, Bartosz EE, Cathers PD, Caussyn DD, Drummer TL, Kemper KW, Kerr PL, Robson D. Compound-nucleus contributions to 6Li+12C scattering. Phys Rev C Nucl Phys 1996; 54:3273-3276. [PMID: 9971703 DOI: 10.1103/physrevc.54.3273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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16
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Scheit H, Glasmacher T, Brown BA, Brown JA, Cottle PD, Hansen PG, Harkewicz R, Hellström M, Ibbotson RW, Jewell JK, Kemper KW, Morrissey DJ, Steiner M, Thirolf P, Thoennessen M. New Region of Deformation: The Neutron-Rich Sulfur Isotopes. Phys Rev Lett 1996; 77:3967-3970. [PMID: 10062354 DOI: 10.1103/physrevlett.77.3967] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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17
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Kerr PL, Kemper KW, Green PV, Mohajeri K, Myers EG, Schmidt BG, Hnizdo V. 6Li-vector+12C inelastic scattering at 30 and 50 MeV. Phys Rev C Nucl Phys 1996; 54:1267-1281. [PMID: 9971462 DOI: 10.1103/physrevc.54.1267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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18
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Green PV, Kemper KW, Kerr PL, Mohajeri K, Myers EG, Robson D, Rusek K, Thompson IJ. Analyzing powers in 4He(6Li. Phys Rev C Nucl Phys 1996; 53:2862-2869. [PMID: 9971272 DOI: 10.1103/physrevc.53.2862] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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19
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Döring J, Johns GD, Kaye RA, Kemper KW, Sun H, Sylvan GN, Tabor SL. High-K structure in 77As. Phys Rev C Nucl Phys 1996; 53:2674-2681. [PMID: 9971254 DOI: 10.1103/physrevc.53.2674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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20
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Cottle PD, Kemper KW. Comment on "Double-octupole excitations in the N=84 nuclei 144Nd and 146Sm". Phys Rev C Nucl Phys 1996; 53:2017-2019. [PMID: 9971171 DOI: 10.1103/physrevc.53.2017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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21
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Kerr PL, Kemper KW, Green PV, Mohajeri K, Myers EG, Robson D, Schmidt BG. Tensor effects in 6Li. Phys Rev C Nucl Phys 1995; 52:1924-1933. [PMID: 9970706 DOI: 10.1103/physrevc.52.1924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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22
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Tiede MA, Kemper KW, Fletcher NR, Robson D, Caussyn DD, Bennett SJ, Brown JD, Catford WN, Jones CD, Watson DL, Rae WD. Measurement of low-lying states in 9B. Phys Rev C Nucl Phys 1995; 52:1315-1325. [PMID: 9970636 DOI: 10.1103/physrevc.52.1315] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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23
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Jewell JK, Tekyi-Mensah OJ, Cottle PD, Döring J, Green PV, Holcomb JW, Johns GD, Johnson TD, Kemper KW, Kerr PL, Tabor SL, Womble PC, Wood VA. Negative-parity states near the yrast line in 144Nd. Phys Rev C Nucl Phys 1995; 52:1295-1301. [PMID: 9970633 DOI: 10.1103/physrevc.52.1295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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24
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Mendez AJ, Kemper KW, Green PV, Kerr PL, Myers EG, Reber EL, Robson D. Analyzing powers for the 12C(6Li. Phys Rev C Nucl Phys 1995; 51:651-664. [PMID: 9970111 DOI: 10.1103/physrevc.51.651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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25
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Reber EL, Kemper KW, Green PV, Kerr PL, Mendez AJ, Myers EG, Schmidt BG, Hnizdo V. Analyzing powers for elastic and inelastic scattering of polarized 6Li from 12C at 30 MeV. Phys Rev C Nucl Phys 1994; 50:2917-2926. [PMID: 9969992 DOI: 10.1103/physrevc.50.2917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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26
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Liendo JA, Fletcher NR, Caussyn DD, Kemper KW, Towers EE. 15N cluster states in triton transfer and their alpha decay. Phys Rev C Nucl Phys 1994; 50:3155-3158. [PMID: 9970020 DOI: 10.1103/physrevc.50.3155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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27
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Tekyi-Mensah OJ, Cottle PD, Döring J, Green PV, Holcomb JW, Johns GD, Johnson JL, Johnson TD, Kemper KW, Kerr PL, Tabor SL, Womble PC, Wood VA. Weak coupling in 143Nd. Phys Rev C Nucl Phys 1994; 50:R1759-R1762. [PMID: 9969911 DOI: 10.1103/physrevc.50.r1759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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28
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Reber EL, Kemper KW, Green PV, Kerr PL, Mendez AJ, Myers EG, Schmidt BG. Spin-orbit and tensor potentials from polarized 6Li scattering. Phys Rev C Nucl Phys 1994; 49:R1-R4. [PMID: 9969261 DOI: 10.1103/physrevc.49.r1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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29
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Zingarelli RA, Dennis LC, Tiede MA, Kline RC, Kemper KW, Mitchell SV. Complete and incomplete momentum transfer components in the natSi(16O,X) reaction at 96.4, 112.4, and 127.8 MeV. Phys Rev C Nucl Phys 1993; 48:651-661. [PMID: 9968877 DOI: 10.1103/physrevc.48.651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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30
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Cottle PD, Glasmacher T, Johnson JL, Kemper KW. Electron conversion coefficients in 127Ba and 130La. Phys Rev C Nucl Phys 1993; 48:136-139. [PMID: 9968802 DOI: 10.1103/physrevc.48.136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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31
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Reber EL, Kemper KW, Kerr PL, Mendez AJ, Myers EG, Schmidt BG, Hnizdo V. Analyzing powers for elastic and inelastic scattering of polarized 6Li from 9Be at 32 MeV. Phys Rev C Nucl Phys 1993; 48:285-290. [PMID: 9968820 DOI: 10.1103/physrevc.48.285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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32
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Glasmacher T, Caussyn DD, Cottle PD, Holcomb JW, Johnson TD, Kemper KW, Kennedy MA, Womble PC. Evidence for single particle structure of high spin states in 144Pm and 145Pm. Phys Rev C Nucl Phys 1993; 47:2586-2597. [PMID: 9968732 DOI: 10.1103/physrevc.47.2586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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33
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Reber EL, Kemper KW, Kerr PL, Mendez AJ, Myers EG, Schmidt BG, Clarke NM. Analyzing powers for 9Be(6Li. Phys Rev C Nucl Phys 1993; 47:2190-2194. [PMID: 9968675 DOI: 10.1103/physrevc.47.2190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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34
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Vineyard MF, Mateja JF, Beck C, Atencio SE, Dennis LC, Frawley AD, Henderson DJ, Janssens RV, Kemper KW, Kovar DG, Maguire CF, Padalino SJ, Prosser FW, Stephans GS, Tiede MA, Wilkins BD, Zingarelli RA. Energy dependence of fusion evaporation-residue cross sections in the 28Si+12C reaction. Phys Rev C Nucl Phys 1993; 47:2374-2377. [PMID: 9968697 DOI: 10.1103/physrevc.47.2374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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35
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Cottle PD, Kemper KW, Kennedy MA, Fifield LK, Ophel TR. 5(-) "octupole" states in 146,148Nd and 148Sm via proton scattering. Phys Rev C Nucl Phys 1993; 47:1048-1052. [PMID: 9968537 DOI: 10.1103/physrevc.47.1048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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36
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Caussyn DD, Fletcher NR, Kemper KW, Towers EE, Kolata JJ, Lamkin K, Smith RJ, Becchetti FD, Brown JA, Jänecke JW, Roberts DA, Gay DL. Cross section for the primordial reaction 8Li(p,n)8Be (g.s.) at Ec.m.=1.5 MeV. Phys Rev C Nucl Phys 1993; 47:387-391. [PMID: 9968447 DOI: 10.1103/physrevc.47.387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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37
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Kennedy MA, Cottle PD, Kemper KW. Excitations of 21+ and 31- states from (p,p') and electromagnetic measurements. Phys Rev C Nucl Phys 1992; 46:1811-1817. [PMID: 9968300 DOI: 10.1103/physrevc.46.1811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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38
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Meziani Z, Chen JP, Beck D, Boyd G, Chinitz LM, Day DB, Dennis LC, Dodge GE, Fillipone BW, Giovanetti KL, Jourdan J, Kemper KW, Koh T, Lorenzon W, McCarthy JS, McKeown RD, Milner RG, Minehart RC, Morgenstern J, Mougey J, Potterveld DH, Rondon-Aramayo OA, Sealock RM, Sick I, Smith LC, Thornton ST, Walker RC, Woodward C. High momentum transfer RT,L inclusive response functions for 3,4He. Phys Rev Lett 1992; 69:41-44. [PMID: 10046184 DOI: 10.1103/physrevlett.69.41] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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39
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Cottle PD, Glasmacher T, Kemper KW. Spin and parity measurements in 128,129La. Phys Rev C Nucl Phys 1992; 45:2733-2739. [PMID: 9968038 DOI: 10.1103/physrevc.45.2733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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40
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Comer LM, Reber EL, Kemper KW, Robson D, Brown JD, Talley TL. Survey of the (9Be,6He) reaction on 9Be, 10B, 11B, and 12C. Phys Rev C Nucl Phys 1992; 45:1803-1809. [PMID: 9967933 DOI: 10.1103/physrevc.45.1803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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41
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Glasmacher T, Caussyn DD, Cottle PD, Johnson TD, Kemper KW, Womble PC. Evidence for weak coupling in 145Pm. Phys Rev C Nucl Phys 1992; 45:1619-1627. [PMID: 9967914 DOI: 10.1103/physrevc.45.1619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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42
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Brown JD, Jacobsen ER, Kemper KW. Search for a 21.4-MeV state in 13C and (p, pi +) production mechanisms. Phys Rev C Nucl Phys 1991; 44:2581-2583. [PMID: 9967693 DOI: 10.1103/physrevc.44.2581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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43
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Cottle PD, Kemper KW. Identification of nuclear cluster-molecular states. Phys Rev C Nucl Phys 1991; 44:1901-1904. [PMID: 9967611 DOI: 10.1103/physrevc.44.1901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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44
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Cottle PD, Kennedy MA, Kemper KW, Brown JD, Jacobsen ER, Sharon YY, Leitch EM, Mabuchi H, Mao ZQ, Slivka T, Greene EJ. Test of octupole coupled 5(-) state in 146Nd using proton inelastic scattering. Phys Rev C Nucl Phys 1991; 44:1668-1671. [PMID: 9967573 DOI: 10.1103/physrevc.44.1668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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45
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Tiede MA, Trcka DE, Kemper KW. Energy dependence of 6Li+28Si elastic scattering and the dispersion relation. Phys Rev C Nucl Phys 1991; 44:1698-1700. [PMID: 9967581 DOI: 10.1103/physrevc.44.1698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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46
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Caussyn DD, Aziz SM, Cottle PD, Glasmacher T, Kemper KW. Conversion electron spectroscopy of high spin states in 143,144Nd. Phys Rev C Nucl Phys 1991; 43:2098-2102. [PMID: 9967262 DOI: 10.1103/physrevc.43.2098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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47
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Chen JP, Meziani ZE, Beck D, Boyd G, Chinitz LM, Day DB, Dennis LC, Dodge G, Filippone BW, Giovanetti KL, Jourdan J, Kemper KW, Koh T, Lorenzon W, McCarthy JS, McKeown RD, Milner RG, Minehart RC, Morgenstern J, Mougey J, Potterveld DH, Rondon-Aramayo OA, Sealock RM, Smith LC, Thornton ST, Walker RC, Woodward C. Longitudinal and transverse response functions in 56Fe(e,e') at momentum transfer near 1 GeV/c. Phys Rev Lett 1991; 66:1283-1286. [PMID: 10043166 DOI: 10.1103/physrevlett.66.1283] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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48
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Cottle PD, Aziz SM, Kemper KW, Owens ML, Reber EL, Brown JD, Jacobsen ER, Sharon YY. Proton inelastic scattering on the transitional nucleus 144Nd. Phys Rev C Nucl Phys 1991; 43:59-65. [PMID: 9967046 DOI: 10.1103/physrevc.43.59] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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49
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Aziz SM, Kemper KW. 11B(7Li,t) and the (p, pi +) reaction. Phys Rev C Nucl Phys 1991; 43:347-349. [PMID: 9967077 DOI: 10.1103/physrevc.43.347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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50
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Cottle PD, Aziz SM, Kemper KW, Owens ML, Reber EL, Brown JD, Jacobsen ER, Sharon YY. Non-octupole origin of the 51- state in 144Nd. Phys Rev C Nucl Phys 1990; 42:762-764. [PMID: 9966767 DOI: 10.1103/physrevc.42.762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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