W. N. Catford

Spectroscopy of neutron-rich Dy-168,Dy-170: Yrast band evolution close to the NpNn valence maximum

The yrast sequence of the neutron-rich dysprosium isotope Dy-168 has been studied using multinucleon transfer reactions following collisions between a 460-MeV Se-82 beam and an Er-170 target. The reaction products were identified using the PRISMA magnetic spectrometer and the gamma rays detected using the CLARA HPGe-detector array. The 2(+) and 4(+) members of the previously measured ground-state rotational band of Dy-168 have been confirmed and the yrast band extended up to 10(+). A tentative candidate for the 4(+) -> 2(+) transition in Dy-170 was also identified. The data on these nuclei and on the lighter even-even dysprosium isotopes are interpreted in terms of total Routhian surface calculations and the evolution of collectivity in the vicinity of the proton-neutron valence product maximum is discussed. (Less)

TIARA: A large solid angle silicon array for direct reaction studies with radioactive beams

A compact, quasi-4pi position sensitive silicon array, TIARA, designed to study direct reactions induced by radioactive beams in inverse kinematics is described here. The Transfer and Inelastic All-angle Reaction Array (TIARA) consists of 8 resistive-strip silicon detectors forming an octagonal barrel around the target and a set of double-sided silicon-strip annular detectors positioned at each end of the barrel. The detector was coupled to the gamma-ray array EXOGAM and the spectrometer VAMOS at the GANIL Laboratory to demonstrate the potential of such an apparatus with radioactive beams. The 14N(d,p)15N reaction, well known in normal kinematics, has been carried out in inverse kinematics for that purpose. The observation of the 15N ground state and excited states at 7.16 and 7.86 MeV is presented here as well as the comparison of the measured proton angular distributions with DWBA calculations. Transferred l-values are in very good agreement with both theoretical calculations and previous experimental results obtained in normal kinematics.

Structure of

The low-lying level structure of the unbound neutron-rich nucleus

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Be probed via secondary beam reactions

Be has been investigated via breakup on a carbon target of secondary beams of

SHARC: Silicon Highly-segmented Array for Reactions and Coulex used in conjunction with the TIGRESS γ-ray spectrometer

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Migration of Nuclear Shell Gaps Studied in the d(Ne-24, p gamma)Ne-25 Reaction

B at 35 MeV/nucleon. The coincident detection of the beam velocity

Isomeric decay studies in neutron-rich N ≈ 126 nuclei

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Anomalies in the Charge Yields of Fission Fragments from the U(n,f)238 Reaction

Be fragments and neutrons permitted the invariant mass of the

ALPHA-CLUSTER STATES POPULATED IN 24Mg + 12C

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