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Proton and α-particle energy spectra were measured in coincidence with fission fragments at different relative angles in 16O (96 MeV) + 232Th reaction. The multiplicity spectra were analyzed within the framework of a Moving Source Disentangling Analysis (MSDA) to determine contributions from different emission stages. The MSDA conclusively shows “Near Scission Emission (NSE)” as an essential component in the multiplicity spectra. In contrast to NSE α particles which emit mainly perpendicular (“equatorial emission”), the NSE protons are observed to be emitted perpendicular as well as parallel (“polar emission”) to the fission axis with similar intensities (~20% for each). Thus, around 40% of total pre-scission protons are emitted near the scission stage, whereas the same fraction for α particles is only around 10%. The inevitable presence of “polar” and “equatorial” NSE protons in a heavy-ion induced fission has been observed for the first time. Present results open up a new avenue to study the heavy-ion induced fission dynamics.

Quasi-elastic (QEL) scattering measurements have been performed using a 28Si projectile off a 90Zr target at energies around the Coulomb barrier. A Bayesian analysis within the framework of coupled channels (CC) calculations is performed in a large parameter space of quadrupole and hexadecapole deformations (β2 and β4) of 28Si. Our results unambiguously show that 28Si is an oblate shaped nucleus with β2=-0.38±0.01 which is in excellent agreement with results from electromagnetic probes. The sign and magnitude of quadrupole deformation along with a precise value of hexadecapole deformation (β4=+0.03±0.01) of 28Si have been determined for the first time using QEL scattering. A remarkable agreement is obtained between the experimental and calculated β4 values of 28Si based on Skyrme-Hartree-Fock method. The present results demonstrate the strong sensitivity of the quasi-elastic scattering to the sign and magnitude to the ground state deformation parameters, thus affirming its suitability to be used for rare exotic nuclei using low intensity RIBs.

The pre-scission α-particle multiplicity (αpre), measured in 16O (96 MeV) + 232Th reaction, is observed to be significantly lower than the global trend reported earlier. Statistical model calculations also show a much shorter fission-time to reproduce the experimental αpre. By assimilating the previous measurements, it is observed that the αpre makes a changeover from high to a very low value while crossing the Businaro Gallone point in mass asymmetry in the entrance channels in heavy-ion induced fission of 232Th. Similar discontinuous behavior with respect to the entrance channel mass asymmetry was observed earlier in fission fragment angular anisotropy data, and it was attributed to “pre-equilibrium fission”. The present results on αpre provide compelling evidence for an admixture of non-equilibrium fission which depends on the entrance channel dynamics.

Background and aims. Most portal vein thromboses (PVT) in cirrhotics are discovered incidentally. While case series demonstrate improved portal vein patency with anti-coagulation, there is little information on impact of PVT on morbidity and mortality. This study aimed to compare morbidity and mortality in cirrho-tics with untreated PVT with those without PVT.Material and methods. Cirrhotics evaluated for orthotopic liver transplant in a single large transplant center were prospectively followed. Subjects had contrast CT or MRI at initial evaluation and serial imaging every 6 months until transplantation, removal from the list or death. Univariate and multivariate Cox regression analysis were used to assess associations between new PVT and factors of interest.Results. Of the 290 prospectively followed cirrhotics who met inclusion criteria, PVT was detected in 70 (24.1%)-47 had PVT at the time of initial evaluation and 23 developed one during the pre-transplant study period. A third of the patients with PVT had re-canalization or spontaneous resolution of thrombus while awaiting transplantation. There was no difference in the pre or post-transplant mortality between cirrhotics with and without PVT.Conclusion. Cirrhotics with untreated PVT fared equally well as those without PVT before and after transplantation. Further studies with larger numbers of patients are needed to determine if anticoagulation therapy truly improves outcomes in cirrhotics with portal vein thrombosis.