Coulomb excitation of 11Be

doi:10.1016/S0370-2693(96)01690-5

Physics Letters B

Volume 394, Issues 1–2, 20 February 1997, Pages 11-15

https://doi.org/10.1016/S0370-2693(96)01690-5 Get rights and content

Abstract

The Coulomb excitation of a halo nucleus ¹¹Be to its first bound excited state (E1: $12^{+} → 12^{−}$ ) has been studied using a 64 MeV/u ¹¹Be radioactive beam incident on a ²⁰⁸Pb target. The electric dipole strength deduced by a first-order perturbation analysis is in good agreement with the result of previous life-time measurements of the ¹¹Be $12^{−}$ state.

References (23)

T. Motobayashi
Phys. Lett. B
(1995)
T. Nakamura
Phys. Lett. B
(1994)
S. Shimoura
Phys. Lett. B
(1995)
J. Kiener
Nucl. Phys. A
(1993)
T. Motobayashi
Phys. Rev. Lett.
(1994)
C.A. Bertulani
Phys. Rev. C
(1994)
J.D. Jackson
Classical Electrodynamics
(1975)
S.S. Hanna et al.
Phys. Rev. C
(1971)
S. Typel et al.
Phys. Lett. B
(1995)
T. Kubo
Nucl. Instr. and Meth. B
(1992)

T. Kikuchi et al., Phys. Lett. B, in...

Cited by (60)

BlueSTEAl: A pair of silicon arrays and a zero-degree phoswich detector for studies of scattering and reactions in inverse kinematics
2024, Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
BlueSTEAl, the Blue (aluminum chamber of) Silicon TElescope Arrays for light nuclei, has been developed to study direct reactions in inverse kinematics, as well as scattering and breakup reactions using radioactive ion beams. It is a detector system consisting of a pair of annular silicon detector arrays and a zero-degree phoswich plastic scintillator. For typical binary reaction studies in inverse kinematics, light ions are detected by the Si array in coincidence with heavy recoils detected by the phoswich placed at the focal-plane of a zero-degree magnetic spectrometer. The Si array can also be used to detect light nuclei such as beryllium and carbon with clear isotope separation, while the phoswich can also be placed at zero degrees without a spectrometer and used as a high-efficiency beam counting monitor with particle identification capability at the rate of up to $\sim$ 5 × 10⁴ particles per second. This paper reports on the capabilities of BlueSTEAl as determined by recent experiments performed at the Texas A&M Cyclotron Institute. The device is also anticipated to be used in future experiments at other radioactive ion beam facilities.
Three-body breakup of <sup>6</sup>He and its halo structure
2021, Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
The Borromean halo nucleus ⁶He has been studied by a kinematically complete measurement of Coulomb and nuclear breakup into α + 2n on Pb and C targets at 70 MeV/nucleon. Fully quantum-mechanical four-body breakup calculations reproduce the energy and angular differential cross sections below $E_{rel} \sim 1$ MeV for both targets. The model used here reproduces the ⁶He ground-state properties as well as α-n and n-n scattering data and predicts an average opening angle $〈 θ_{n n} 〉$ of 68^∘ between the two halo neutrons. However, the model underestimates the breakup cross sections for higher $E_{rel}$ , indicating a possible contribution from the inelastic breakup. Alternatively, we examine the empirically modified calculations that reproduce the energy-differential cross sections for a wide range of scattering angles for both targets. The extracted B(E1) peaks at $E_{rel} \sim 1.4$ MeV and amounts to 1.6(2) e² fm² for $E_{rel}$ ≤ 20 MeV, resulting $〈 θ_{n n} 〉$ = 56 $_{- 10}^{+ 9}$ degrees. In either interpretation, the current results show evidence of the dineutron spatial correlation in ⁶He.
DALI2: A NaI(Tl) detector array for measurements of γ rays from fast nuclei
2014, Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
A NaI(Tl) detector array called DALI2 (Detector Array for Low Intensity radiation 2) has been constructed for in-beam γ-ray spectroscopy experiments with fast radioactive isotope (RI) beams. It consists typically of 186 NaI(Tl) scintillators covering polar angles from ~15° to ~160° with an average angular resolution of 6° in full width at half maximum. Its high granularity (good angular resolution) enables Doppler-shift corrections that result in, for example, 10% energy resolution and 20% full-energy photopeak efficiency for 1-MeV γ rays emitted from fast-moving nuclei (velocities of $v / c ≃ 0.6$ ). DALI2 has been employed successfully in numerous experiments using fast RI beams with velocities of v/c=0.3–0.6 provided by the RIKEN RI Beam Factory.
Precision measurement of the electromagnetic dipole strengths in Be11
2014, Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
The electromagnetic dipole strength in ${}^{11}{Be}$ between the bound states has been measured using low-energy projectile Coulomb excitation at bombarding energies of 1.73 and 2.09 MeV/nucleon on a ${}^{196}{Pt}$ target. An electric dipole transition probability $B (E 1; 1 / 2^{-} \to 1 / 2^{+}) = 0.102 (2) e^{2} {fm}^{2}$ was determined using the semi-classical code Gosia, and a value of $0.098 (4) e^{2} {fm}^{2}$ was determined using the Extended Continuum Discretized Coupled Channels method with the quantum mechanical code FRESCO. These extracted $B (E 1)$ values are consistent with the average value determined by a model-dependent analysis of intermediate energy Coulomb excitation measurements and are approximately $14 %$ lower than that determined by a lifetime measurement. The much-improved precisions of 2% and 4% in the measured $B (E 1)$ values between the bound states deduced using Gosia and the Extended Continuum Discretized Coupled Channels method, respectively, compared to the previous accuracy of $\sim 10 %$ will help in our understanding of and better improve the realistic inter-nucleon interactions.
Recent experimental progress in nuclear halo structure studies
2013, Progress in Particle and Nuclear Physics
Recent developments (since the last review in J. of Physics G by I. Tanihata in 1996 [1]) at RIB facilities opened possibilities of detailed studies of halo nuclei. New facilities have been constructed to provide higher intensity beams of radioactive nuclei in a wide range of energies. At the time of the last review, only secondary beams by projectile fragmentation were the production source of halo nuclei for use in reaction studies. Since then, re-acceleration facilities have been developed and thus high-quality low-energy beams become available for the reaction studies. The wide variety of new data are thus available on halo nuclei and nuclei on and outside of proton and neutron drip lines.
Low energy beams provided a means to determine the masses and charge radii of halo nuclei (^6,8He, ¹¹Li). Also transfer reactions have been measured in many nuclei far from the stability line. In fragmentation facilities, new experimental methods such as gamma ray detection in coincidence with breakup fragments of halo nuclei have been developed. Also the reaction cross sections have been measured in a wide range of beam energies. In addition, proton elastic scattering of halo nuclei has been measured at high energies. All together, studies of density distribution, identification of shell orbitals and spectroscopic factors of halo wave function became possible. Such studies reveal many new important information such as the change of magic numbers in nuclei far from the stability line.
In this article, we would like to review the experimental developments on halo nuclei and other related drip line nuclei. Also the new view of the nuclear structure learned from such studies will be discussed. Development of selected theories on related nuclear structure problems will be mentioned briefly.
Energy levels of light nuclei A=11
2012, Nuclear Physics A

View all citing articles on Scopus

^☆: The present work is supported by the Grant-In-Aid for Scientific Research of the Japan Ministry of Education, Science and Culture under the program number 05243102.

¹: Fax: +81-3-3811-0960

View full text

Coulomb excitation of 11Be☆

Abstract

Phys. Lett. B

Phys. Lett. B

Phys. Lett. B

Nucl. Phys. A

Phys. Rev. Lett.

Phys. Rev. C

Phys. Rev. C

Phys. Lett. B

Nucl. Instr. and Meth. B

Coulomb excitation of ¹¹Be☆