Pressure-tuned First-order Phase Transition and Accompanying Resistivity Anomaly in CeZn_{1-\delta}Sb_{2}

The Kondo lattice system CeZn_{0.66}Sb_{2} is studied by the electrical resistivity and ac magnetic susceptibility measurements at several pressures. At P=0 kbar, ferromagnetic and antiferromagnetic transitions appear at 3.6 and 0.8 K, respectively. The electrical resistivity at T_N dramatically changes from the Fisher-Langer type (ferromagnetic like) to the Suzaki-Mori type near 17 kbar, i.e., from a positive divergence to a negative divergence in the temperature derivative of the resistivity. The pressure-induced SM type anomaly, which shows thermal hysteresis, is easily suppressed by small magnetic field (1.9 kOe for 19.8 kbar), indicating a weakly first-order nature of the transition. By subtracting a low-pressure data set, we directly compare the resistivity anomaly with the SM theory without any assumption on backgrounds, where the negative divergence in d\rho/dT is ascribed to enhanced critical fluctuations in the presence of superzone gaps.Comment: 5 pages, 4 figures; journal-ref adde

Extraction of Technetium by Tri-n-octyl Amine Impregnated Resin

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Particle production in Au + Au collisions from BNL E866

In this article, we present recent results on particle production from Au+Au collisions at 11 A GeV/c obtained by the E866 experiment. The experiment studies the particle production in high baryon density matter created in central Au + Au collisions. Preliminary results of proton and pion production have been reported in previous Quark Matter conferences. Two particle correlation data for Au + Au collisions in this experiment are presented in another paper in this conference

Event Reconstruction in the PHENIX Central Arm Spectrometers

The central arm spectrometers for the PHENIX experiment at the Relativistic Heavy Ion Collider have been designed for the optimization of particle identification in relativistic heavy ion collisions. The spectrometers present a challenging environment for event reconstruction due to a very high track multiplicity in a complicated, focusing, magnetic field. In order to meet this challenge, nine distinct detector types are integrated for charged particle tracking, momentum reconstruction, and particle identification. The techniques which have been developed for the task of event reconstruction are described.Comment: Accepted for publication in Nucl. Instrum. A. 34 pages, 23 figure

Regularities of Extraction of Uranyl Thenoyltrifluoroacetonate into a Number of Solvents

The extraction equilibria were investigated of the thenoyltrifluoroacetone (TTA) chelate of uranyl ion between aqueous perchlorate medium and thirteen organic solvents, The extracted species was shown to be UO_2A_2. The solubility parameter of the chelate was estimated from the partition data and its was con-firmed that the relationship log P_M =n log P_+const. holds for the present system. When the extraction constant (K_) is considered in relation to the distribution coefficients, the K_ values are expected to be constant under certain conditions for all of the solvents ; the log K_ values were found to be constant (log K_ =-2.85±0.17)