First measurement of the isoscalar giant resonances in a neutron rich exotic nucleus (68Ni) using Maya active target

The study of the Isoscalar Giant Monopole Resonance (ISGMR) and the Isoscalar Giant Quadrupole Resonance (ISGQR) in stable nuclei provided relevant information on both nuclear matter and nuclear structure in past decades. For instance the centroid of the ISGMR can be linked to the incompressibility modulus of the infinite nuclear matter. Values for exotic nuclei would help in constraining it. In unstable nuclei, only one measurement has been performed so far (56Ni) and in order to study the evolution of the ISGMR and the ISGQR along an isotopic chain, measurements in neutron-rich Ni are called for.To reach this goal, a dedicated experiment was performed at GANIL in Septembre 2010. A 68Ni beam at 50 AMeV and with an intensity of 10^4 pps has been produced on LISE beamline. The inelastic scattering of alpha (alpha, alpha’) and deuteron particles (d,d’) on 68Ni in inverse kinematics has been studied with the active target Maya. It is the first attempt to measure the ISGMR and ISGQR in an unstable neutron-rich nucleus. For each experiment, the excitation energy spectrum has been reconstructed and the angular distributions have been studied with two independant methods. Experimental differential cross sections have been compared to DWBA calculations using RPA transition density in order to deduce the properties of the states observed. Concerning the analysis in (alpha, alpha’), the ISGMR is fragmented with a shoulder at 21.1+/-0.6 MeV, the ISGQR is concentred at 16.9+/-0.8 MeV and exhausted 61+/-17% of the Energy Weighted Sum Rule (EWSR). Moreover, a « soft GMR », predicted but never observed, is identified at 13.4+/-0.5 MeV. All these results are confirmed with the experiment in (d,d’), with the exception of the ISGQR due to unadapted experimental conditions.

Data and Resources

Additional Info

Field Value
Source https://theses.hal.science/tel-00872712
Author Vandebrouck, Marine
Maintainer CCSD
Last Updated May 9, 2026, 09:26 (UTC)
Created May 9, 2026, 09:26 (UTC)
Identifier NNT: 2013PA112142
Language fr
Rights https://about.hal.science/hal-authorisation-v1/
contributor Institut de Physique Nucléaire d'Orsay (IPNO) ; Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
creator Vandebrouck, Marine
date 2013-09-13T00:00:00
harvest_object_id 3c34ea1b-945f-4c04-b09b-d6c6cb741af6
harvest_source_id 3374d638-d20b-4672-ba96-a23232d55657
harvest_source_title test moissonnage SELUNE
metadata_modified 2026-03-31T00:00:00
set_spec type:THESE