Top Mass Measurements at the Tevatron Run II

The latest top quark mass measurements by the CDF and D\O~ experiments are presented here. The mass has been determined in the dilepton (\ttbar \to e\mu,ee,\mu\mu + jets +\met) and lepton plus jets (\ttbar \to e or $\mu$ + jets +\met) final states. The most accurate single result from lepton plus jets channel is 173.5$^{+3.7}_{-3.6}$(stat. + Jet Energy Scale Systematic)$\pm1.3$(syst.) ~GeV/c$^{2}$, which is better than the combined CDF and D\O~ Run~I average. A preliminary and unofficial average of the best experimental Run~II results gives $M_{top}$ = $172.7\pm3.5$ GeV/c${^2}$.Comment: 19 pages, 8 figures, presented at 19th Rencontres de Physique De La Vallee D'Aoste, La Thuil

SEASONAL FLUCTUATIONS IN THE RATE OF UNEMPLOYMENT IN BULGARIA

The main purpose of the present study is to estimate the influence of the seasonality factor on the rate of unemployment in Bulgaria by comparing it with the European Union including its current 28 members. The dynamics and seasonal fluctuations in the rate of unemployment in Bulgaria have been studied by means of statistical models. The conclusion reached is that the seasonality factor exerts a greater influence on the rate and dynamics of unemployment in Bulgaria in comparison with the EU economy as a whole.The main purpose of the present study is to estimate the influence of the seasonality factor on the rate of unemployment in Bulgaria by comparing it with the European Union including its current 28 members. The dynamics and seasonal fluctuations in the rate of unemployment in Bulgaria have been studied by means of statistical models. The conclusion reached is that the seasonality factor exerts a greater influence on the rate and dynamics of unemployment in Bulgaria in comparison with the EU economy as a whole

THE INFLUENCE OF THE FACTOR OF SEASONALITY ON THE REAL GDP OF BULGARIA

The main purpose of the present study is to analyze and forecast the dynamics of the real GDP of Bulgaria and to estimate the influence of the factor of seasonality. The dynamics and the seasonal fluctuations of the real GDP of Bulgaria have been studied by means of statistical models. A comparative analysis between Bulgaria and the European Union (EU-28) has been made. A conclusion has been reached that the factor of seasonality exerts a greater influence on the dynamics of the GDP in Bulgaria in comparison with the economy of the European Union as a whole.The main purpose of the present study is to analyze and forecast the dynamics of the real GDP of Bulgaria and to estimate the influence of the factor of seasonality. The dynamics and the seasonal fluctuations of the real GDP of Bulgaria have been studied by means of statistical models. A comparative analysis between Bulgaria and the European Union (EU-28) has been made. A conclusion has been reached that the factor of seasonality exerts a greater influence on the dynamics of the GDP in Bulgaria in comparison with the economy of the European Union as a whole

Information and thermodynamic arrows of time

The article examines the thermodynamic arrow of time and the information arrow of time. The thermodynamic arrow of time is related to the second law of thermodynamics, and the information arrow of time shows that it is only possible to record information from the past, but not from the future. It has been concluded that on certain occasions the thermodynamic arrow of time and the information arrow of time may have different directions. According to the interpretation of Stueckelberg-Feynman-Sudarshan-Recami, the antiparticles are particles moving backwards in time. Classical thermodynamics can be extended to describe the physical properties of antimatter in two mutually exclusive ways: CP-invariant or CPT-invariant thermodynamics. From this point of view, the article shows the existing possibilities for the directions of the thermodynamic arrow of time and the information arrow of time. Thermodynamic systems have been examined that are composed of only matter or of only antimatter and observed (investigated) by hypothetical observers made of matter or antimatter. The information and entropy properties of the computational processes performed by a computer made of antimatter have been discussed

Calculations of spin-disorder resistivity from first principles

Spin-disorder resistivity of Fe and Ni is studied using the noncollinear density functional theory. The Landauer conductance is averaged over random disorder configurations and fitted to Ohm's law. The distribution function is approximated by the mean-field theory. The dependence of spin-disorder resistivity on magnetization in Fe is found to be in excellent agreement with the results for the isotropic s-d model. In the fully disordered state, spin-disorder resistivity for Fe is close to experiment, while for fcc Ni it exceeds the experimental value by a factor of 2.3. This result indicates strong magnetic short-range order in Ni at the Curie temperature.Comment: 3 pages, 3 figure

Measurements of Protein-Protein Interactions by Size Exclusion Chromatography

A method is presented for determining second virial coefficients B_2 of protein solutions from retention time measurements in size exclusion chromatography (SEC). We determine B_2 by analyzing the concentration dependance of the chromatographic partition coefficient. We show the ability of this method to track the evolution of B_2 from positive to negative values in lysozyme and bovine serum albumin solutions. Our SEC results agree quantitatively with data obtained by light scattering.Comment: 18 pages including 1 table and 5 figure

Interface states in CoFe2O4 spin-filter tunnel junctions

Spin-filter tunneling is a promising way to generate highly spin-polarized current, a key component for spintronics applications. In this work we explore the tunneling conductance across the spin-filter material CoFe2O4 interfaced with Au electrodes, a geometry which provides nearly perfect lattice matching at the CoFe2O4/Au(001) interface. Using density functional theory calculations we demonstrate that interface states play a decisive role in controlling the transport spin polarization in this tunnel junction. For a realistic CoFe2O4 barrier thickness, we predict a tunneling spin polarization of about -60%. We show that this value is lower than what is expected based solely on considerations of the spin-polarized band structure of CoFe2O4, and therefore that these interface states can play a detrimental role. We argue this is a rather general feature of ferrimagnetic ferrites and could make an important impact on spin-filter tunneling applications.Comment: 5 pages, 4 Figures plus 1 page supplemen

Magnetization, Low Field Instability and Quench of RHQT Nb(3)Al Strands

Since 2005, we made and tested three RHQT Nb{sub 3}Al strands, one with Nb matrix and two with Ta matrix, which are fully stabilized with Cu electroplating. We observed anomalously large magnetization curves extending beyond 1 to 1.5 Tesla with the F1 Nb matrix strand at 4.2 K, when we measured its magnetization with a balanced coil magnetometer. This problem was eliminated with the Ta matrix strands operating at 4.2 K. But with these strands a similar but smaller anomalous magnetization was observed at 1.9 K. We studied these phenomena with FEM. With the F1 Nb matrix strand, it is explained that at low external field, inter-filamentary coupling currents in the outer layers of sub-elements create a shielding effect. It reduces the inside field, keeps the inside Nb matrix superconductive, and stands against a higher outside field beyond the Hc of Nb. At an even higher external field, the superconductivity of the whole Nb matrix collapses and releases a large amount of energy, which may cause a big quench. Depending on the size of the energy in the strand or the cable, a magnet could quench, causing the low field instability. Some attempt to analyze the anomaly with FEM is presented