Heavy Ion Coulomb Excitation and Gamma Decay Studies of the One and Two Phonon Giant Dipole Resonances in ‘O*Pb and 2ogBi
نویسندگان
چکیده
Projectile photon coincidences were measured for the scattering of an 80 MeV/nucleon 64Zn beam from *‘*Pb and *“Bi targets at the GANIL heavy ion accelerator facility. Projectile-like particles between 0.5” and 4.5“ relative to the incident beam direction were detected in the SPEG energy loss spectrometer where their momentum, charge, and mass were determined. Photons were detected in the BaF2 scintillation detector array TAPS. Light charged particles produced in the reaction were detected in the KVI Forward Wall. The analysis of the data acquired in this experiment is focused on three different phenomena: (1) the two phonon giant dipole resonance, (2) time dependence of the decay of the one phonon giant dipole resonance, and (3) giant resonance strength in projectile nuclei.
منابع مشابه
th / 9 90 80 03 v 1 2 A ug 1 99 9 Microscopic Studies on Two - Phonon Giant Resonances
A new class of giant resonances in nuclei, namely double giant resonances, is discussed. They are giant resonances built on top of other giant resonances. Investigation on their properties, together with similar studies on low-lying two-phonon states, should give an answer on how far the harmonic picture of boson-type excitations holds in the finite fermion systems like atomic nuclei. The main ...
متن کاملA ug 1 99 8 Nonlinear Enhancement of the Multiphonon Coulomb Excitation in Relativistic Heavy Ion Collisions
We propose a soluble model to incorporate the nonlinear effects in the transition probabilities of the multiphonon Giant Dipole Resonances based on the SU(1,1) algebra. Analytical expressions for the multi-phonon transition probabilities are derived. Enhancement of the Double Giant Resonance exci-tation probabilities in relativistic ion collisions scales as (2k + 1)(2k) −1 for the degree of non...
متن کاملDouble giant resonances in deformed nuclei
We report on the first microscopic study of the properties of two-phonon giant resonances in deformed nuclei. The cross sections of the excitation of the giant dipole and the double giant dipole resonances in relativistic heavy ion collisions are calculated. We predict that the double giant dipole resonance has a one-bump structure with a centroid 0.8 MeV higher than twice energy for the single...
متن کاملInfluence of damping on the excitation of the double giant resonance
We study the effect of the spreading widths on the excitation probabilities of the double giant dipole resonance. We solve the coupledchannels equations for the excitation of the giant dipole resonance and the double giant dipole resonance. Taking Pb + Pb collisions as example, we study the resulting effect on the excitation amplitudes, and cross sections as a function of the width of the state...
متن کاملCoulomb Excitation of Double Giant Dipole Resonances
We implement the Brink–Axel hypothesis for the excitation of the double giant dipole resonance (DGDR): The background states which couple to the one–phonon giant dipole resonance are themselves capable of dipole absorption. These states (and the ones which couple to the two–phonon resonance) are described in terms of the Gaussian Orthogonal Ensemble of random matrices. We use second–order time–...
متن کامل