Cl35+12C as

Abstract

The fully energy-damped yields from the 35 Clϩ 12 C reaction have been systematically investigated using particle-particle coincidence techniques at a 35 Cl bombarding energy of ϳ8 MeV/nucleon. The fragmentfragment correlation data show that the majority of events arises from a binary-decay process with rather large numbers of secondary light-charged particles emitted from the two excited exit fragments. No evidence is observed for ternary break-up events. The binary-process results of the present measurement, along with those of earlier, inclusive experimental data obtained at several lower bombarding energies are compared with predictions of two different kinds of statistical model calculations. These calculations are performed using the transition-state formalism and the extended Hauser-Feshbach method and are based on the available phase space at the saddle point and scission point of the compound nucleus, respectively. The methods give comparable predictions and are both in good agreement with the experimental results thus confirming the fusionfission origin of the fully damped yields. The similarity of the predictions for the two models supports the claim that the scission point configuration is very close to that of the saddle point for the light 47 V compound system. The results also give further support for the specific mass-asymmetry-dependent fission barriers needed in the transition-state calculation. ͓S0556-2813͑96͒02407-7͔

Towards a unified description of evaporation-residue fusion cross-sections above the barrier

“…2 (fig. 5) [29] 16O+27Al [34] 32S+12C [39] 20Ne+26Mg [40] 20Ne+27Al [41] 35Cl+12C [42] 16O+40Ca [46] 28Si+28Si [48] 32S+24Mg [53] 19F+40Ca [55] 32S+27Al [54] 35Cl+24Mg [57] 23Na+40Ca [55] 28Si+40Ca [55,60] (4)) in the fusion region III is shown as full darkred curve in both panels. The darkgreen dash-dotted curve in inset is due to the same kind of fit to the fusion region II.…”

“…Despite a broad coverage in the α and N sys /Z sys variables many of data are for the mass symmetric systems and, in particular, for the systems with the equal number of neutrons N sys and protons Z sys . About 100 additional data points from those measurements which have reported existence of a non-negligible fusion-fission component will be presented p-1 [18,19] 20Ne+16O [20] 24Mg+12C [21] 12C+27Al [22] 16O+24Mg [23] 20Ne+20Ne [20] 28Si+12C [24,25] 14N+27Al [26] 16O+26Mg [23] 18O+24Mg [23] 16O+27Al [27][28][29] 32S+12C [30][31][32][33][34] 20Ne+26Mg [35] 20Ne+27Al [28,36] 20Ne+27Al [28,36] 35Cl+12C [37][38][39] 16O+32S [28] 16O+40Ca [40,41] 28Si+28Si [42][43][44][45][46] 28Si+28Si [42][43][44][45][46] 32S+24Mg [47,48] 19F+40Ca [49,50] 32S+27Al [28,49] 35C...…”

Dissipative collisions in16O+27Alat<

“…The energy spectra of different fragments at each angle have been fitted with two Gaussian functions in the following way. In the first step, the FF contributions have been obtained by fitting the energy distributions with a Gaussian having centroid at the energies obtained from Viola systematics [18,19] of total kinetic energies(TKE) of mass-symmetric fission fragments duly corrected for asymmetric factor [20] . The width of the Gaussian was obtained by fitting the lower energy tail of the spectra, assuming it to be originating from purely FF process.…”

Study of the fusion-fission process in the 35Cl +24Mg reaction

“…Nevertheless, the properties of the primary fission fragments can be deduced, even at energies as high as 275 MeV, by using the coincident data. As found for the 35 Cl+ 12 C reaction at the same incident energy [24] and at lower energies studied [3,6] The energy calibrations of the IC's were obtained using elastically scattered 35 Cl projectiles from 100 µg/cm 2 thick Au and C targets and from the Mg target, combined with measurements of α sources and a calibration pulser. On an event-by-event basis, corrections were applied for energy loss in the targets and in the entrance window foils on the IC's and for the pulse height defect in the Si detectors [30].…”

“…This study was motivated by the renewed interest in the role of clustering in light nuclei and a linear chain configuration of three-16 O cluster-like is predicted in 48 Cr by both the cluster model [26] and macroscopic energy calculations [27]. No supportive evidence was found via the 24 Mg+ 24 Mg entrance channel [25] but other studies are underway by using alternative reactions such as 36 Ar+ 12 C [28]. As a matter of fact sequential light-fragment emissions from the reaction fragments can lead to large undetected nuclear charge deficits between the observed and entrance-channel total charges rather than a third big fragment.…”