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DOE OSTI · 1902855

Dissipative Reactions with Intermediate-Energy Beams: A Novel Approach to Populate Complex-Structure States in Rare Isotopes

Gade, A.·Brown, B. A.·Weisshaar, D.·Bazin, D.·Brown, K. W.·Charity, R. J.·Farris, P.·Hill, A. M.·Li, J.·Longfellow, B.·Rhodes, D.·Reviol, W.·Tostevin, J. A.
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Abstract

A novel pathway for the formation of multiparticle-multihole excited states in rare isotopes is reported from highly energy- and momentum-dissipative inelastic-scattering events measured in reactions of an intermediate-energy beam of 38 Ca on a Be target. The negative-parity, complex-structure final states in 38 Ca are observed following the in-beam γ-ray spectroscopy of events in the 9 Be( 38 Ca, 38 Ca + γ)X reaction in which the scattered projectile loses longitudinal momentum of order Δp || = 700 MeV/c. Here, the characteristics of the observed final states are discussed and found to be consistent with the formation of excited states involving the rearrangement of multiple nucleons in a single, highly energetic projectile-target collision. Unlike the far-less-dissipative, surface-grazing reactions usually exploited for the in-beam γ-ray spectroscopy of rare isotopes, these more energetic collisions appear to offer a practical pathway to nuclear-structure studies of more complex multiparticle configurations in rare isotopes—final states conventionally thought to be out of reach with high-luminosity fast-beam-induced reactions.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICSEnergy levels & level densitiesNuclear reactionsNuclear structure & decaysenergy levels & level densitiesnuclear reactionsnuclear structure & decays

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Gade, A., Brown, B. A., Weisshaar, D., Bazin, D., Brown, K. W., Charity, R. J., Farris, P., Hill, A. M., Li, J., Longfellow, B., Rhodes, D., Reviol, W., Tostevin, J. A.. 2022-12-07. Dissipative Reactions with Intermediate-Energy Beams: A Novel Approach to Populate Complex-Structure States in Rare Isotopes. https://doi.org/10.1103/physrevlett.129.242501

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