We measured absolute cross sections for neutron transfer channels populated in the Rb94+Pb208 binary reaction. Cross sections have been extracted identifying directly the lead isotopes with the high ...efficiency MINIBALL γ-ray array coupled to a particle detector combined with a radioactive Rb94 beam delivered at Elab=6.2 MeV/nucleon by the HIE-ISOLDE facility. We observed sizable cross sections in the neutron-rich mass region, where the heavy partner acquires neutrons. A fair agreement between the measured cross sections with those from GRAZING calculations gives confidence in the cross-section predictions of more neutron-rich nuclei produced via a larger number of transferred nucleons.
The magnetic dipole moments (μ) of 209Tlg (N=128) and 207Tlm (N=126) have been measured for the first time using the in-source laser resonance-ionization spectroscopy technique with the Laser Ion ...Source and Trap (LIST) at ISOLDE (CERN). The application of the LIST suppresses the usually overwhelming background of the isobaric francium isotopes and allows access to heavy thallium isotopes with A⩾207. The self-consistent theory of finite Fermi systems based on the energy density functional by Fayans et al. well describes the N dependence of μ for 1/2+ thallium ground states, as well as μ for the 11/2− isomeric states in europium, gold and thallium isotopes. The inclusion of particle-vibration coupling leads to a better agreement between the theory and experiment for μ(Tlg, Iπ=1/2+). It is shown that beyond mean-field contributions to μ cannot be neglected at least for thallium isotopes with Iπ=1/2+.
The neutron rich carbon isotope 15C is the only known case of an almost "pure" 2s1/2 single-neutron halo ground state configuration. At collision energies around the Coulomb barrier the reaction ...dynamics is expected to be dominated by single neutron transfer and breakup. To investigate these effects, we have measured the scattering of 15C with a 208Pb target at 65 MeV at the HIE-ISOLDE facility in CERN (Geneva, Switzerland). The preliminary data demonstrates the presence of a strong long-range absorption pattern in the angular distribution of the elastic cross section. The results are discussed in the framework of Optical Model calculations.
Background: Models describing nuclear fragmentation and fragmentation fission deliver important input forplanning nuclear physics experiments and future radioactive ion beam facilities. These models ...are usuallybenchmarked against data from stable beam experiments. In the future, two-step fragmentation reactions withexotic nuclei as stepping stones are a promising tool for reaching the most neutron-rich nuclei, creating a needfor models to describe also these reactions.Purpose: We want to extend the presently available data on fragmentation reactions towards the light exoticregion on the nuclear chart. Furthermore, we want to improve the understanding of projectile fragmentationespecially for unstable isotopes.Method: We have measured projectile fragments from 10,12−18C and 10−15B isotopes colliding with a carbontarget. These measurements were all performed within one experiment, which gives rise to a very consistent dataset. We compare our data to model calculations.Results: One-proton removal cross sections with different final neutron numbers (1pxn) for relativistic 10,12−18Cand 10−15B isotopes impinging on a carbon target. Comparing model calculations to the data, we find that theEPAX code is not able to describe the data satisfactorily. Using ABRABLA07 on the other hand, we find that theaverage excitation energy per abraded nucleon needs to be decreased from 27MeV to 8.1 MeV.With that decreaseABRABLA07 describes the data surprisingly well.Conclusions: Extending the available data towards light unstable nuclei with a consistent set of new data hasallowed a systematic investigation of the role of the excitation energy induced in projectile fragmentation. Moststriking is the apparent mass dependence of the average excitation energy per abraded nucleon. Nevertheless,this parameter, which has been related to final-state interactions, requires further study.
Neutron-rich Ba isotopes are expected to exhibit octupolar correlations, reaching their maximum in isotopes around mass A = 146. The odd-A neutron-rich members of this isotopic chain show typical ...patterns related to non-axially symmetric shapes, which are however less marked compared to even-A ones, pointing to a major contribution from vibrations. In the present paper we present results from a recent study focused on 148-150Cs β-decay performed at the ISOLDE Decay Station equipped with fast-timing detectors. A detailed analysis of the measured decay half-lives and decay scheme of 149Ba is presented, giving a first insight in the structure of this neutron-rich nucleus.
Nucleosynthesis in Type I X-ray bursts (XRB) proceeds eventually through the rp-process near the proton drip-line. Several N=Z nuclei act as waiting points in the reaction network chain. ...Astrophysical calculations of XRB light curves depend upon the theoretical modelling of the beta decays of interest, with the N=Z waiting points
64
Ge,
68
Se,
72
Kr,
76
Sr, and their second-neighbours N=Z+2 being key nuclei in this context. We have carried out different experimental campaigns at ISOLDE (CERN) to determine the B(GT) distributions, in the decay of several N=Z, N=Z+2 and their daughters, of particular relevance in rp-process calculations. To this aim the Total Absorption Spectroscopy technique is applied. Here we present results on the beta decay of
64
Ga and the status of the analysis of
64
Ge. Our results provide benchmarks for testing and constraining models under terrestrial conditions that can be used later for predictions in stellar environments.
Study of exotic decay of Cs isotope close to the proton drip line Das, P.; Dattaf, Ushasi; Chakraborty, S. ...
27th International Nuclear Physics Conference, INPC 2019,Glasgow, United Kingdom,2019-07-29 - 2019-08-02,
12/2020, Letnik:
1643, Številka:
1
Journal Article, Conference Proceeding
Recenzirano
Odprti dostop
The neutron-deficient 115Cs was produced at ISOLDE, CERN by spallation reaction using 1.4 GeV proton on LaC2 target. The exotic decay modes were studied by using a charged particle array (DSSD and ...pad detectors) and a γ-detector array (four Clovers) at the ISOLDE decay station (IDS). In this report, results on observed β-delayed particle emission from 115Cs, a nucleus close to proton drip line, is presented. By measuring the time distribution in the delayed proton spectrum, the half-life of the ground state of 115Cs was extracted. The obtained half-life is in agreement with previous reported value. For the first time, the p-unbound states of 115Xe, obtained by measuring beta-delayed protons from 115Cs is reported.
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