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[en] Transverse energy and charged particle multiplicity produced in 14.6 GeV/c p + Al and p + Pb collisions have been studied using the E814 set-up at the BNL-AGS. Measurements of dσ/dET, dET/dη,dσ/dNc, and dNc/dη are presented. From the present data the mean transverse energy per particle is obtained and it is compared to values observed in Si induced collisions at the same energy In contrast to what is observed in nucleus-nucleus collisions, a very weak correlation is found between the transverse energy and the charged particle multiplicity. These results are compared to the predictions of various theoretical models used to describe heavy-ion collisions. The event generators RQMD and HIJET reproduce well the pseudorapidity distribution of both the transverse energy and charged particle multiplicity, whereas FRITIOF fails to reproduce the measured distributions. Contrary to what had been suggested previously in a Si + A study, the present study shows that the pseudorapidity dependence of charged particle multiplicity distributions do not follow KNO scaling. (author)
[en] We present measurements of pion elliptic flow (ν2) in Au + Au collisions at √(sNN)=200,62.4,39,27and19.6GeV, as a function of event-by-event charge asymmetry (A±), based on data from the STAR experiment at RHIC. We find that π−(π+) elliptic flow linearly increases (decreases) with charge asymmetry for most centrality bins and for all the beam energies under study. The slope parameter (r) from ν2(A±) difference between π− and π+ shows a centrality dependency similar to calculations of the Chiral Magnetic Wave. The measurements of charge separation with respect to the reaction plane in search of Local Parity Violation and the Chiral Magnetic Effect are also presented for Au+Au collisions at √(sNN)=200,62.4,39,27,19.6,11.5and7.7GeV, and for U + U collisions at 193 GeV
[en] Highlights: •The recent research progress in CDA safety analysis of LFRs is reviewed. •Study achievements and limitations on CDA of LFRs are discussed. •Further study aspects of CDA safety analysis of LFRs are suggested. -- Abstract: The LBE- or Lead-cooled Fast Reactor (LFR) is a kind of advanced reactor which is included in the Generation IV nuclear energy systems. The Core Disruptive Accident (CDA), which is also called severe accident, is meaningful for the research and development (R&D) work of LFRs. In this paper, the recent numerical simulation and experimental research progress on accident scenarios and key phenomena in the reactor primary system after CDA happens is reviewed and summarized, aiming at providing a useful reference for the future CDA study and safety assessment of LFRs. In the recent numerical simulation studies, the investigations of fuel dispersion processes were in the majority. The analysis results indicated that the occurrence risks of re-criticality in CDA conditions for different LFR designs were different. The numerical simulation research on molten material freezing behavior mainly served the verification of calculation models of safety analysis codes. The experimental studies on mobility behavior of solid particles and molten material freezing were also mainly used to verify the safety analysis codes. The numerical and experimental studies on fuel and coolant interaction (FCI) in CDAs of LFRs were both very few. Three potential further research aspects are suggested for the future study on CDA safety analysis of LFRs. The numerical simulation on fuel particle dispersion processes in CDAs of new LFR designs is still suggested as the essential study content as it is much more effective and convenient. Further experiments for code verification and phenomenon study in CDAs are also necessary, which could close some research gaps for CDA safety analysis of LFRs.
[en] As the first step of fast reactor development in China, China Experimental Fast Reactor (CEFR), one of the key projects of the National High Technology Research and Development Program (863 Program), will reach the first physical criticality in 2009 and will be connected to grid in 2010. The CEFR project includes R and D, design, construction, commissioning and operation, and its technology and management are very complex. This paper describes its position, objective, task, management, and analyzes its characteristics. (authors)
[en] The propagation of longitudinal and transverse elastic waves oblique or perpendicular to the laminations of infinite periodically layered fourfold system is studied. Comprehensive study is performed for the one-dimensional phononic crystals with locally resonant structures. Compared with its three- and two-dimensional counterparts, additional resonance is found in this one-dimensional case
[en] Highlights: • The severe accident issues of LBE-cooled reactors are summarized. • Key processes and phenomena during CDAs of LBE-cooled reactors are discussed. • The systematic framework of severe accident safety analysis of LBE-cooled reactors is given. - Abstract: The safety analysis work is always a key issue for the nuclear power plant licensing. After Fukushima Accident of Japan, the severe accident safety analysis has been more concerned, which would be also very important and essential for the Research and Development (R&D) work of LBE-cooled reactors. So far, a great number of studies on severe accident of LBE-cooled reactors have been carried out. In this paper, a summary of severe accident of LBE-cooled reactors is conducted, which contains almost all the relevant issues on the hypothetical Core Disruptive Accidents (CDAs). Detailed contents of these issues are discussed. The systematic framework of severe accident safety analysis of LBE-cooled reactors is preliminarily given, which aims at providing a useful reference for the further safety analysis research work of this kind of advanced reactor.
[en] Highlights: • A natural circulation LBE-cooled research reactor is developed by Institute of Nuclear Energy Safety Technology. • The safety advantages for 10 MW_t_h fast and ADS reactors under loss of heat sink were compared. • A neutronics and thermal-hydraulics coupled simulation code NTC was employed in this study. - Abstract: A natural circulation LBE-cooled research reactor developed by Institute of Nuclear Energy Safety Technology (INEST) is proposed and designed to be 10 MW_t_h. The reactor has two operation modes, which are LBE-cooled critical fast reactor mode and LBE-cooled accelerator-driven sub-critical system (ADS) reactor mode. In this paper, protected loss of heat sink (PLOHS) and unprotected loss of heat sink (ULOHS) transient accidents were simulated for both the critical and ADS reactors above by NTC-2D code, aiming at the investigation of the safety advantages for the two reactor modes under this typical transient condition (loss of heat sink, LOHS). The results showed that during PLOHS for both the two modes, all the key parameters (core power, fuel, cladding and coolant temperatures in the hottest channel) decreased to very small values after the reactor scrammed, which meant the reactors under the two modes were both safe. For ULOHS, the fuel, cladding and coolant temperatures of the fast reactor increased smaller than those of the sub-critical one, which means the fast reactor had a better safety advantage under LOHS transient
[en] We present STAR's measurements of directed flow (v1) and elliptic flow (v2) for charged hadrons in AuAu collisions at 62 and 200 GeV, as a function of pseudorapidity, pt and centrality. v2 results in CuCu collisions at 200 GeV are also presented