The inverse kinematics thick target scattering method (TTIK) was used to measure the 8Li resonant elastic scattering on a 4He target in order to investigate 8Li-α cluster configurations in excited ...states of 12B. A 8Li beam at Ebeam 30.6 MeV, provided by the radioactive beam facility EXCYT of LNS in Catania, while passing through a thick Helium target decreases continuously its energy. Thus, elastic scattering can be induced starting from the initial beam energy down to zero. Time of flight measurement between beam particles passing through a MCP detector and α-particles impinging on the ΔE stage of a Si telescope detector allows the discrimination of elastic scattering from nuclear reaction events, thus representing an improvement of the TTIK method. In this paper the used experimental technique and preliminary results will be described.
A beam detector system, CATS (Chambre A Trajectoires de Saclay), was designed to provide event-by-event particle tracking in experiments with radioactive beams at GANIL. It consists of two low ...pressure multiwire proportionnal chambers with one plane of anode wires placed between two cathode planes (active area: 70×70
mm
2), respectively segmented into 28 vertical or horizontal strips (2.54
mm wide). The anode wires deliver a time signal allowing a time of flight measurement with an accuracy between 440
ps and 1.2
ns, depending on the energy loss of incident particles in the detector. The cathode strips are individually read out and the position of incoming particles is reconstructed using a charge centroid finding algorithm. A spatial resolution of 400
μm (700
μm) was achieved during in beam experiment, with a counting rate of 1.5×10
5 (10
6) particles per second.
The 8Li + 4He →11B + n reaction at Ecm<2 MeV is a process of relevant astrophysical interest for which a remarkable experimental discrepancy between inclusive and exclusive cross-section measurements ...exists. In this Letter, a new inclusive neutron measurement at Ecm=1.05±0.16 MeV is given. The radioactive 8Li beam was delivered by the EXCYT facility. The cross section was determined by a low-background measurement of the time correlation between the 8Li projectile arrival to the target and the following neutron capture in a threshold-less 4π thermalization counter. This new data strengthens the reliability of the previous inclusive reaction cross-section data and altogether are consistent with a significant population of 11B levels at high excitation energy.
Fusion cross sections are extracted for the
7
Li$ + $
28
Si system, via reaction cross section and transfer measurements at sub- and near-barrier energies (
E
lab
= 5.7 to 14MeV). The energy ...evolution of transfer to reaction cross section ratios is determined with the aid of CDCC calculations, which subsequently allows the deduction of fusion cross sections at sub- and near-barrier energies. It is shown that fusion can be well represented in a BPM context. Fusion cross sections are compared for the systems
7
Li$ + $
28
Si and
6
Li$ + $
28
Si, the latter studied previously, and are found to exhibit different strengths. Last, the direct channels determined at 13MeV, are found to be dominated by a 2
n
-transfer mechanism.
The results concerning the study of 6Li+120Sn and 7Li+119Sn systems are presented. These two sistems are characterised by very similar structures of the interacting nuclei and by different Q-value ...for one-and two- neutron transfer. Our aim is to disentangle the possible effects due to the different n-transfer Q-values, at sub-barriers energies, by comparing the two fusion excitation function. In these experiments the fusion cross section has been measured by using a stack activation technique. No particular differences in the two fusion excitation functions have been observed.
The first reaction spectroscopy on the ground state structure of 33Mg through the measurement of the longitudinal momentum distribution from the one-neutron removal reaction using a C target at 898A ...MeV is reported. The experiment was performed at the FRS, GSI. The distribution has a relatively narrow width (150±3 MeV/c (FWHM)) and the one-neutron removal cross-section is 74±4 mb. An increased contribution from the 2p3/2 orbital is required to explain the observation showing its lowering compared to existing model predictions. This provides new information regarding the configuration of 33Mg and the island of inversion.
Schottky Mass Spectrometry (SMS) and Isochronous Mass Spectrometry (IMS) have been successfully applied for direct mass measurements of exotic nuclides at FRS-ESR facility at GSI. Both experimental ...methods are sensitive to single stored ions and can cover very efficiently a large number of nuclides in one run. Presently, more than 1100 masses of different nuclides have been covered by SMS and IMS in several FRS-ESR experiments whereby about 350 of them have been determined for the first time. In this paper, we present the status of our experimental program and use the experimental mass values to test the predictive power of modern mass models.
The study of fusion in collision around the Coulomb barrier, induced by radioactive or stable weakly bound nuclei, has been the subject of many experiments in the last years. From a semiclassical ...point of view, direct processes like break-up or transfer may be favoured by the low binding energies and one might also expect suppressed fusion cross section due to the competition with the break-up. However, according to the Coupled Channel calculations (CC), it is well known that the presence of strong open reaction channels can be responsible for a fusion cross-section enhancement with respect to the single barrier penetration calculations and the break-up should be included in such calculations. In order to further investigate on this topic, the 6Li+64Zn collision has been studied at several energies around the Coulomb barrier, to extract the total fusion and the total reaction cross sections and to study the energy dependence of the optical model potential.
Different excited states of
13
C populated in the
10
B +
10
B reactions at a beam energy of 72.2 MeV were investigated. The study revealed both well-known and new, or infrequently populated states. ...In particular, the inclusive excitation energy spectra showed the presence of most of the states belonging to the K = 3/2
-
rotational band that was proposed by several authors. Furthermore, a possibly new state at E
x
= 19.0 MeV was strongly populated in the
α
+
9
Be coincidences. The measured state was found to have a well defined cluster structure. Additionally, so far unobserved
α
-decay of the two rarely seen high-energy
13
C states at 21.9 and 23.6 MeV is discussed.
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