Fission time measurements: a new probe into super-heavy element stability

Accepted for publication in Physical Review LettersReaction mechanism analyses performed with a 4 $\pi$ detector for the systems $^{208}$Pb+Ge, $^{238}U+Ni and$^{238}$U+Ge, combined with analyses of the associated reaction time distributions, provide us with evidence for nuclei with Z=120 and 124 living longer than$10^−18$s and arising from highly excited compound nuclei. By contrast, the neutron deficient nuclei with Z=114 possibly formed in$^{208}$Pb+Ge reactions have shorter lifetimes, close to or below the sensitivity limit of the experiment

Evidence of Z=120 compound nucleus formation from lifetime measurement in the 238^{238}U+Ni reaction at 6.62 MeV/nucleon

CAS NIMThe formation of compound nuclei with Z=120, followed by fission, has been evidenced in the 238U+Ni system at 6.62 MeV/nucleon by very long reaction times (t ~ 10-17s) measured by the blocking technique in single crystals

Bimodality: a possible experimental signature of the liquid-gas phase transition of nuclear matter

We have observed a bimodal behaviour of the distribution of the asymmetry between the charges of the two heaviest products resulting from the decay of the quasi-projectile released in binary Xe+Sn and Au+Au collisions from 60 to 100 MeV/u. Event sorting has been achieved through the transverse energy of light charged particles emitted on the quasi-target side, thus avoiding artificial correlations between the bimodality signal and the sorting variable. Bimodality is observed for intermediate impact parameters for which the quasi-projectile is identified. A simulation shows that the deexcitation step rather than the geometry of the collision appears responsible for the bimodal behaviour. The influence of mid-rapidity emission has been verified. The two bumps of the bimodal distribution correspond to different excitation energies and similar temperatures. It is also shown that it is possible to correlate the bimodality signal with a change in the distribution of the heaviest fragment charge and a peak in potential energy fluctuations. All together, this set of data is coherent with what would be expected in a finite system if the corresponding system in the thermodynamic limit exhibits a first order phase transition.Comment: 30 pages, 31 figure

Stochastic unit commitment in microgrids based on model predictive control

This article deals with the problem of Stochastic Unit Commitment (SUC), considering the stochastic nature of demand and meteorological phenomena. This paper shows the optimal operation of a hybrid microgrid composed of the following generation units: wind turbine (WT), photovoltaic solar panel (PV), diesel engine generator (DE), micro-turbine (MT), as well as storage devices such as Battery Energy Storage (BES), considering its constraints and the requirements of the reserve generation. For this purpose, a Model-based Predictive Control (MPC), which uses dynamic models of prediction of renewable power and demand in real time, is developed, allowing feedback at each step of time, which corrects the uncertainty of the models. A comparison with a classic UC formulation has been made. The results reach a lower cost solution

Model-independent tracking of criticality signals in nuclear multifragmentation data

We look for signals of criticality in multifragment production in heavy-ion collisions using model-independent universal fluctuations theory. The phenomenon is studied as a function of system size, bombarding energy, and impact parameter in a wide range of INDRA data. For very central collisions (b/b_ma

Evolution of the multifragmentation of the Xe + Sn system from 25 up to 150 AMeV

ALADI

Renal Collecting System Calcified Hematoma Following Parenchymal Perforation by Ureteral Stent in Kidney Transplantation: A Case Report

Introduction: Renal parenchymal perforation by ureteral stent placement is a rare but serious complication. There is also a paucity of data regarding collecting system hematomas and potential calcification in renal allografts. Case presentation: We report a unique case of a 51-year-old male who underwent unrelated living-donor kidney transplantation with stent incorporation during ureteroneocystostomy. Post-operatively he was found to have renal parenchymal perforation by the ureteral stent resulting in a pelvicalyceal hematoma with subsequent calcification and obstruction. At the time of guidewire introduction for percutaneous nephrolithotomy one year later, a nephrostogram and passage of a hydrophilic guidewire resulted in improved contrast drainage into the bladder, so the invasive surgery was no longer needed. Discussion: There are few reported cases of renal parenchymal perforation by a ureteral stent, none of which resulted in a collecting system hematoma. The calcification of urinary tract hematomas is also rare and attributed to metabolic abnormalities, prolonged stagnation of blood, and infection. Conclusions: We suspect the nephrostogram and guidewire introduction created enough antegrade pressure and mechanical disruption to force the calcified hematoma into the bladder