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Nowadays, the accuracy of experimental results relies more and more on detailed simulations. In the STEREO experiment, the interaction of neutrinos in the liquid scintillator is signed by a n-capture on a Gd atom. The FIFRELIN predictions of the Gd γ-cascades were shown to significantly improve the Data/MC agreement. In the CRAB method, lately proposed to calibrate cryogenic particle detectors at low energy (100 eV), the FIFRELIN cascades of the W and Ge isotopes played a central role in the feasibility study of the method. The FIFRELIN code employs a Monte Carlo Hauser-Feshbach framework based on Bečvár’s algorithm. A sample of nuclear level schemes is generated for a specific isotope of interest, taking into account the uncertainties from nuclear structure. In this work, new improvements on the FIRELIN de-excitation process are reported. Angular correlations of γ-rays in the de-excitation process have been implemented in order to provide a more accurate description of the γ-ray cascades. The anisotropy of the γ-rays with respect to the axis of a previously emitted γ-ray is modeled using the angular correlation formalism, which requires input of the spins and multipolarities of the states involved in the FIFRELIN cascade. Furthermore, the simulation of primary γ-rays emitted from (n,γ) reactions has been updated using the EGAF database.

The FIFRELIN Monte Carlo code has been upgraded recently by adding new capabilities, additional models and updated databases. Several examples are presented in this work as well as three different applications related to the prompt component in fission, gamma cascades from thermal neutron capture and the delayed component in fission associated to the time evolution of decay heat.

7 pags., 5 figs., 1 app., The space and time configurations of the dissociation of He into He+n+n, on C and Pb targets, have been explored simultaneously for the first time. The final-state interactions in the n-n and He-n channels are successfully described within a model that considers independent emission of neutrons from a Gaussian volume with a given lifetime. The dissociation on C target exhibits a dominant sequential decay through the ground state of He, consistent with neutrons being emitted from a Gaussian volume of fm with a n-n delay in the sequential channel of 1400 400 fm/c, in agreement with the lifetime of He. The lower-statistics data on Pb target correspond mainly to direct breakup, and are well described using the n-n volume measured, without any n -n delay. The validity of the phenomenological model used is discussed., The support provided by the technical staff of LPC and the LISE crew is gratefully acknowledged, as are the efforts of the GANIL cyclotron operation team for providing the primary beam. We also wish to express our appreciation for the vital contributions made by our late colleague and friend Jean-Marc Gautier to all the CHARISSA+DEMON experiments undertaken by our collaboration.

International audience; Nuclear fission is a complex process, still not yet well described by microscopic models, and its main observables are difficultto measure with accuracy. Following the capture of a thermal neutron the compound nucleus fissions in two fragments. Mostof the energy of the process is transferred in kinetic energy, whereas the nuclei are let in few tens of MeV excited states. Thisexcitation energy is then released, the majority of it within less than some nanoseconds, by the evaporation of a few neutronsand the emission of -rays in cascade.To overcome the low accuracy of microscopic models in the prediction of fission observables, nuclear technology relies onlibraries of evaluated data and semi-empirical models, like the GEF model for fission yield evaluations. Such a strategy requestssystematic and accurate experimental data on the few possible observables. Here we will present the advantages of studyingyields of fragment correlated pairs and their de-excitations using an array of high-resolution -ray detectors directly placedaround an actinide target irradiated by a thermal or cold neutron beam. Such a setup was installed at ILL in 2012 and 2013(EXILL) and campaigns were performed with 235U and 241Pu targets. This study is largely motivated by the future installation of apermanent -ray detector array at the ILL, which will be coupled to fission fragment detectors in a first construction phase and afragment separator in a second phase (FIPPS).An important outcome of EXILL data is the observation of the -ray cascade occurring in both fission fragments with an unambiguousdetermination of the fragments. The cascade is directly linked with the angular momentum of the fragments afterscission, which is one of the less precise and less understood properties. With the development of new simulation codes for theneutron evaporation and the -ray cascade like FIFRELIN or KEWPIE, systematic studies and comparisons with the large amountof experimental data resulting from double and triple gamma-ray coincidence analysis become possible. Preliminary results onthe gamma–ray cascades measured in the well produced Kr and Ba fragments and comparisons with FIFRELIN simulations willbe presented.

We analyzed the experimental data of the pre-scission neutron multiplicity in connection with fission fragments in the reaction $^{58}$Ni+$^{208}$Pb at the incident energy corresponding to the excitation energy of compound nucleus $E^{*}$=185.9 MeV, which was performed by D\'{e}MoN group. The relation between the pre-scission neutron multiplicity and each reaction process having different reaction time is investigated. In order to study the fusion-fission process accompanied by neutron emission, the fluctuation-dissipation model combined with a statistical model is employed. It is found that the fusion-fission process and the quasi-fission process are clearly distinguished in correlation with the pre-scission neutron multiplicity., Comment: 11 figures

The effects of entrance channel with different projectile and target nuclei combinations on the fission of the 220 90 Th * , 254 102 No * and 256 104 Rf * compound nuclei are investigated. The dependence of the de-excitation of the compound nucleus on the dynamics of the entrance channel is analyzed for the first time. We find that the fission branching ratio Γ f / Γ tot of the compound nucleus formed in the two different reactions with massive nuclei is different due to the dynamical effects in the entrance channel even at the same excitation energy E * . It is caused by the different partial fusion cross section σ l fus ( E ) for those reactions. Consequently, the excitation function of evaporation residues measured in such reactions is strongly related to the effect of the entrance channel. This phenomenon is explained by the dependence of the capture and fusion cross sections on the orbital angular momentum of collision.

Prompt gamma-ray activation analysis (PGAA) is proposed as a complementary non-destructive multi-elemental method to PIXE. At the end of 2005, a new state-of-the-art PGAA facility will be built at the research reactor II (FRM II) at Garching near Munich, Germany. The facility has been moved to FRM II from the. Paul Scherrer Institute (PSI), Switzerland, where it was successfully running from 1997 to 2001. The main principles, characteristics and advantages of the PGAA technique and the expectations for the redesigned PGAA facility (regarding the conditions of the FRM II) are presented. The new PIXE/IBA instrument built at the 10 MV tandem accelerator of the Nuclear Physics Institute of the University of Cologne is presented. For the detection of x-rays, mainly a small Peltier-cooled XFlash detector is used, which brings the advantage of its capability to acquire up to 300 kcps. The data acquisition is performed by digital electronics with a system based on DGF-4C modules from X-ray Instrumentation Associates (XIA) and with in-house-developed acquisition software. For the analysis of the spectra, the Gupix program is used. After the calibration of our PIXE instrument with thin MicroMatter standards, homogeneous powders of NIST Standard Reference Materials (SRM) were measured. The PIXE results were compared with nominal values given by NIST and with the results of the PGAA measurement at PSI in 2001. Our plan is to have at our disposal analytical methods (PIXE, PIGE, RBS, PGAA and neutron tomography) that can serve for applied research.

We discuss thc fusion-fission process in superheavy mass region. By analyzing the mass distribution of fission fragments, we can distinguish between fusion-fission process and quasi-fission process. We investigate these two processes using the fluctuation-dissipation model. In the dynamical calculation, we employ the three-dimensional Langevin equation. We find 90 ∼ 99% of mass symmetric fission events come from the quasi-fission process in the superheavy mass region. In order to classify the fusion-fission process more precisely. we analyze the pre-scission neutron multiplicity. © 2004 Elsevier B.V. All rights reserved.

Nuclear dissipation in capture reactions is investigated using backtracing, a new analysis protocol. Combining analysis procedure with dynamical models, the difficult and long-standing problem of competition and mixing between quasifission and fusion-fission is solved for the first time. The nature of the relevant dissipation is determined as one-body dissipation. At low excitation energy where shell effects are strongly effective, the shape of the mass distribution could be a powerful check of the nature and the magnitude of the dissipation.

We study the effect of the entrance channel and the shell structure of reacting massive nuclei on the fusion mechanism and the formation of evaporation residues of heavy and superheavy nuclei. In the framework of the combined dinuclear system concept and advanced statistical model, we analyze the 40 Ar + 176 Hf, 86 Kr + 130 Xe and 124 Sn + 92 Zr reactions leading to 216 Th * ; the 32 S + 182 W, 48 Ti + 166 Er, and 60 Ni + 154 Sm reactions leading to 214 Th * ; the 40 Ar + 181 Ta reaction leading to 221 Pa * ; the 48 Ca + 248 Cm reaction leading to the 296 116 compound nucleus. In our calculations of the excitation functions for capture, fusion and evaporation residues we use the relevant variables such as mass-asymmetry of nuclei in the entrance channel, relative distance between nuclear centers, shell effect and shape of colliding nuclei and such characteristics of the reaction mechanism as potential energy surface, driving potential, the dependence of capture, fusion cross sections and survival probabil...

Nuclear fission yields data measurements for thermal neutron induced fission of 241Pu have been carried out at the Institut Laue Langevin (ILL) in Grenoble, using the Lohengrin mass spectrometer. Mass, isotopic and isomeric yields have been extracted for the last measurements. A focus is given in this document to the mass yield results which are obtained for almost the entire heavy peak and most of the light high yields masses, along with the covariance matrix. The mean kinetic energy as a function of the fission product mass has also been extracted from the measurements. The total mean kinetic energy pre and post neutron emission have been assessed and compared to other works showing a rather good agreement.

Aims: The aim of the present report was to evaluate current methods of in vitro analysis of three-dimensional (3D) scaffolds seeded with human bone marrow stromal cells (hBMSCs) from six bone marrow aspirates for tissue engineered growth of bone. Methods: A series of experiments was conducted to compare methods of cell expansion and to validate analysis of proliferation and differentiation of hBMSCs in long term cultures of up to 40 days in 3D scaffolds of calcium carbonate (CaCO3) and mineralized collagen. Proliferation within the seeded scaffolds was monitored using cell counting, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT), neutral red (NR) and DNA fluorescence assays and compared with empty controls. Differentiation was assessed by means of ELISA for osteocalcin (OC) and real time PCR for OC and collagen I (Coll I). Results: The results showed that the scaffold differed in seeding efficacy (CaCO3: 53.3%, min. Coll.: 83.3%). The precise identification of the number of cells in biomaterials by MTT, NR and DNA assays was problematic, as MTT and NR assay overestimated the number of cells, whereas DNA assay grossly underestimated the number of cells on the scaffolds. Monitoring of changes over time may be biased by unspecific material-dependent background activity that has to be taken into account. Identification of osteogenic differentiation is not reliable by identifying osteogenic markers such as OC in the supernatant but has to be done on the transcriptional level. Conclusions: It is concluded that monitoring of in vitro procedures for the construction of biohybrid scaffolds requires more emphasis in order to make the cell based approach a reliable treatment option in tissue engineering.

Frontoorbital advancement has become a standard method both to increase intracranial volume and to improve facial appearance in patients with syndromal or nonsyndromal craniosynostosis. Relevant complications of this procedure include severe hemorrhage and trauma to intracranial, orbital, or facial soft tissues, which mostly arise during the process of bone exposure or osteotomy. To minimize the risk of soft tissue injury and to increase the precision of the osteotomy, the authors applied a piezoelectric osteotome for frontoorbital advancement in 15 patients with craniosynostosis seen consecutively (mean age 11.3 months). They demonstrated that this new device can cut cranial bones using ultrasonic microvibrations created by piezoelectric effects. In all patients, this instrument allowed an easy and precise handling during osteotomy with a reduced amount of trauma to adjacent soft tissues and with no complications. Although the time required for piezoelectric osteotomy was longer compared with conventional techniques, the total operation time remained approximately the same because the preparation requirements are less extensive. Postoperatively, bone regeneration was uneventful. The authors conclude that this new technique of piezoelectric osteotomy is a valuable tool for craniofacial reconstructive surgery in pediatric patients.

The interest in the study of the fission process of superheavy nuclei mainly deals with the opportunity to obtain information about the cross-section of the compound nucleus (CN) formation at excitation energies E*\approx 15–30 MeV. It allows one to estimate the survival probability of the superheavy composite system after evaporation of 1–3 neutrons, i.e. in "cold" or "warm" fusion reactions. However, in order to solve this problem deeper understanding of the coalescence processes between colliding nuclei, the competition between fusion-fission and quasi-fission processes is needed. The characteristics of both processes, their manifestation in the experimental observables and the relative contribution to the capture cross-section in dependence on the excitation energies, reaction entrance channel etc were investigated for a wide range of target-projectile combinations. Results of the experiments devoted to the study of the fusion-fission and quasi-fission processes in the reactions of the formation of the superheavy nuclei with Z = 102–122 are presented. The heavy ions 26Mg, 48Ca, 50Ti, 58Fe and 64Ni were used as projectiles. The choice of the reactions with 48Ca and actinide-targets was inspired by the experiments on the production of the isotopes 283112, 289114 and 283116 in Dubna using the same reactions. The 50Ti, 58Fe and 64Ni projectiles were chosen since the corresponding projectile-target combinations lead to the synthesis of even heavier elements. The experiments were carried out at the U-400 accelerator of the Flerov Laboratory of Nuclear Reactions (JINR, Russia) and the XTU Tandem accelerator of the National Laboratory of Legnaro (LNL, Italy) using the time-of-flight spectrometer of fission fragments CORSET. The role of the shell effects, the influence of the entrance channel asymmetry and the deformations of colliding nuclei on the mechanism of the fusion-fission and the competitive process of quasi-fission are discussed. The recent results on synthesis of superheavy nuclei and the perspectives of the "hot" fusion reaction for the production of superheavy nuclei are considered.

Results of the experiments aimed at the study of fission and quasi‐fission processes in the reactions 12C+204Pb, 48Ca+144,154Sm, 168Er, 208Pb, 238U, 244Pu, 248Cm; 58Fe+208Pb, 244Pu, 248Cm, and 64Ni+186W, 242Pu are presented. The choice of the above‐mentioned reactions was inspired by the experiments on the production of the isotopes 283112, 289114 and 283116 at Dubna using the same reactions. The 58Fe and 64Ni projectiles were chosen since the corresponding projectile‐target combinations lead to the synthesis of even heavier elements. The experiments were carried out at the U‐400 accelerator of the Flerov Laboratory of Nuclear Reactions (JINR, Russia), the XTU Tandem accelerator of the National Laboratory of Legnaro (LNL, Italy) and the Accelerator of the Laboratory of University of Jyvaskyla (JYFL, Finland) using the time‐of‐flight spectrometer of fission fragments CORSET and the neutron multi‐detector DEMON. The role of shell effects and the influence of the entrance channel asymmetry and the deformatio...

Measurements of the breakup and the neutron removal reactions of $^{16}\mathrm{C}$ have been made at 46 MeV∕A and the decay cross sections measured. A correlation between the cluster breakup channels and the reaction $\mathrm{Q}$ value suggests that the reaction mechanism is strongly linked to quasielastic processes. No enhancement of the two-body cluster breakup cross section is seen for $^{16}\mathrm{C}$. This result would indicate that $^{16}\mathrm{C}$ does not have a well developed cluster structure in the ground state, in agreement with recent calculations.

The process of fusion-fission of heavy and superheavy nuclei (SHE) with Z = 82-122 formed in the reactions with ^48Ca and ^58Fe ions at energies near and below the Coulomb barrier has been studied. The experiments were carried out at the ^400U accelerator of the Flerov Laboratory of Nuclear Reactions (JINR) and at the XTU Tandem accelerator of the National Laboratory of Legnaro, (LNL) using the time-of-flight spectrometer of fission fragments CORSET and the neutron multi-detector DEMON. As a result of the experiments, mass and energy distributions (MED) of fission fragments, fission, quasi-fission and evaporation residues cross sections, multiplicities of neutrons and gamma quanta and their dependence on the mechanism of formation and decay of compound systems have been studied.

The effects of the entrance channel and shell structure on the experimental evaporation residues have been studied by analyzing the 32S + 182W, 48Ti + 166Er and 60Ni + 154Sm reactions leading to 214Th*; the 40Ar + 181Ta reaction leading to 221Pa*; the 48Ca + 243Am, 248Cm, 249Cf reactions leading to the 291115, 296116 and 297118 superheavy compound nuclei, respectively. The fusion mechanism and the formation of evaporation residues of heavy and superheavy nuclei have been studied. In calculations of the excitation functions for capture, fusion and evaporation residues we used such characteristics as mass asymmetry of nuclei in the entrance channel, binding energies and shape of colliding nuclei, potential energy surface, driving potential, partial-fusion cross-sections and survival probability of the compound nucleus, $\Gamma_{\rm n} / \Gamma_{\rm f}$ ratio at each step along the de-excitation cascade of the compound nucleus. The calculations have allowed us to make useful conclusions about the mechanism of the fusion-fission process, which is in competition with the quasifission process, and the production of the evaporation residues.

The fusion‐fission process for the synthesis of superheavy elements is discussed on the basis of the fluctuation‐dissipation model. Recently the experiments at Dubna on fission of superheavy nuclei were carried out, and the mass and total kinetic energy distributions of fission fragments were measured. By analyzing the mass distribution of fission fragments, we can distinguish between fusion‐fission process and quasi‐fission process. We employ three‐dimensional Langevin equation. We find almost all of the mass symmetric fission events come from the quasi‐fission process in the superheavy mass region. In order to classify the fusion‐fission paths and compare with the experimental data directly, we analyze the pre‐scission neutron emission in the correlation with fission fragments. The neutron multiplicity depends on the travelling time of the trajectory. It is useful to investigate the fusion‐fission process.

Nuclear dissipation in capture reactions is investigated using backtracing. Combining the analysis procedure with dynamical models, the difficult and long-standing problem of competition and mixing of quasi-fission and fusion-fission is solved for the first time. At low excitation energy a new protocol able to handle low statistics data gives access to the prescission neutron multiplicity in two different systems 48 Ca +208 Pb, Pu . The results are in agreement with a domination of fusion-fission in the case of 256 No and an equal mixing of quasi-fission and fusion-fission in the case of Z=114. The nature of the relevant dissipation is determined as one-body dissipation.

After 30 years of production history in the Al-Huwaisah oil field of North Oman, it is still possible to bring best wells on stream. Both vertical and horizontal technologies have been implemented with variable combinations of gas-lifted or ESP completions and barefoot or lined reservoir sections. In addition, these technologies are implemented on this complex carbonate reservoir characterized by a high degree of heterogeneity embedded in four depositional environments (i.e. Channel, Fore Reef, Main Reef and Back Reef) and spread over an area of 22km by 10km with zones of strong and poor aquifer support. This necessitates the need for a sound data gathering strategy to manage the subsurface uncertainties. The improvement in recent production history was mainly the result of implementing a multidisciplinary team approach to define a more structured methodology for identifying the remaining oil targets and ranking them using basic petroleum engineering tools in a more synergistic fashion. Past operational experience has also helped in selecting the best completion and stimulation practices. The outcome of implementing these practices on such a complex field showed that improved oil recovery requires a more flexible approach in field development philosophy in the sense that not always horizontal well technology is better than vertical or lined wells are better than barefoot. The field is currently being evaluated for a possible application of Water-Alternate-Gas (or WAG) hydrocarbon recovery technique. Only parts of the field are found to be acceptable for the WAG pilot test according to the specified pre-requisites for this technology. It is evident that technology solutions for complex carbonate field such as Al-Huwaisah calls for a ‘;dynamic focus’ in the sense that different parts of the field may require different types of technologies to meet the challenges of extremely variable complexity.

The process of fusion-fission of heavy and superheavy nuclei (SHE) with Z = 82-122 formed in the reactions with Ca-48 and Fe-58 ions at energies near and below the Coulomb barrier has been studied. The experiments were carried out at the U-400 accelerator of the Flerov Laboratory of Nuclear Reactions (JINR) and at the XTU Tandem accelerator of the National Laboratory of Legnaro (LNL) using the time-of-flight spectrometer of fission fragments CORSET and the neutron multidetector DEMON. As a result of the experiments, mass and energy distributions (MED) of fission fragments ; fission, quasifission, and evaporation residue cross sections ; and multiplicities of neutrons and gamma-quanta and their dependences on the mechanism of formation and decay of compound systems have been studied.

The aim of the EU FP6-funded ANCIENT CHARM project has been the development of new, and the integration of existing element-sensitive imaging methods utilizing neutrons. We present here the methodology and the first implementation of 3D elemental mapping at the Prompt Gamma Activation Analysis instrument of the research reactor FRM II, in order to determine spatially resolved elemental abundances in samples. After the design, optimization, and characterization of the new setup, measurements were successfully completed on archaeological objects of historical significance from the collection of the Hungarian National Museum.