Use of W-Boson Longitudinal-Transverse Interference in Top Quark Spin-Correlation Functions: II

This continuation of the derivation of general beam-referenced stage-two spin-correlation functions is for the analysis of top-antitop pair-production at the Tevatron and at the Large Hadron Collider. Both the gluon-production and the quark-production contributions are included for the charged-lepton-plus-jets reaction p p or p bar{p} --> t bar{t} --> (W^+ b)(W^- bar{b}) --> (l^{+} nu b)(W^- bar{b}). There is a simple 4-angle beam-referenced spin-correlation function for determination of the relative sign of, or for measurement of a possible non-trivial phase between the two dominant helicity amplitudes for t --> W^{+} b decay. There is an analogous function and tests for bar{t} --> W^{-} bar{b} decay. This signature requires use of the (t bar{t}) c.m.-energy of the hadronically decaying W-boson, or the kinematically equivalent cosine of the polar-angle of W-boson emission in the anti-top (top) decay frame. Spinors and their outer-products are constructed so that the helicity-amplitude phase convention of Jacob & Wick can be used throughout for the fixing of the signs associated with this large W-boson longitudinal-transverse interference effect.Comment: Continuation of hep-ph/0506240 to include gluon-production contribution; 3 "postscript" figures. Equation numbers as in published-on-line EPJ

HaTS: Hardware-Assisted Transaction Scheduler

In this paper we present HaTS, a Hardware-assisted Transaction Scheduler. HaTS improves performance of concurrent applications by classifying the executions of their atomic blocks (or in-memory transactions) into scheduling queues, according to their so called conflict indicators. The goal is to group those transactions that are conflicting while letting non-conflicting transactions proceed in parallel. Two core innovations characterize HaTS. First, HaTS does not assume the availability of precise information associated with incoming transactions in order to proceed with the classification. It relaxes this assumption by exploiting the inherent conflict resolution provided by Hardware Transactional Memory (HTM). Second, HaTS dynamically adjusts the number of the scheduling queues in order to capture the actual application contention level. Performance results using the STAMP benchmark suite show up to 2x improvement over state-of-the-art HTM-based scheduling techniques

Phase relations in the Fe-Ni-Cr-S system and the sulfidation of an austenitic stainless steel

The stability fields of various sulfide phases that form on Fe-Cr, Fe-Ni, Ni-Cr and Fe-Cr-Ni alloys were developed as a function of temperature and the partial pressure of sulfur. The calculated stability fields in the ternary system were displayed on plots of log P sub S sub 2 versus the conjugate extensive variable which provides a better framework for following the sulfidation of Fe-Cr-Ni alloys at high temperatures. Experimental and estimated thermodynamic data were used in developing the sulfur potential diagrams. Current models and correlations were employed to estimate the unknown thermodynamic behavior of solid solutions of sulfides and to supplement the incomplete phase diagram data of geophysical literature. These constructed stability field diagrams were in excellent agreement with the sulfide phases and compositions determined during a sulfidation experiment

Corrosion of 310 stainless steel in H2-H2O-H2S gas mixtures: Studies at constant temperature and fixed oxygen potential

Corrosion of SAE 310 stainless steel in H2-H2O-H2S gas mixtures was studied at a constant temperature of 1150 K. Reactive gas mixtures were chosen to yield a constant oxygen potential of approximately 6 x 10 to the minus 13th power/cu Nm and sulfur potentials ranging from 0.19 x 10 to the minus 2nd power/cu Nm to 33 x 10 to the minus 2nd power/cu Nm. The kinetics of corrosion were determined using a thermobalance, and the scales were analyzed using metallography, scanning electron microscopy, and energy dispersive X-ray analysis. Two corrosion regimes, which were dependent on sulfur potential, were identified. At high sulfur potentials (p sub S sub 2 less than or equal to 2.7 x 10 to the minus 2nd power/cu Nm) the corrosion rates were high, the kinetics obeyed a linear rate equation, and the scales consisted mainly of sulfide phases similar to those observed from pure sulfication. At low sulfur potentials (P sub S sub 2 less than or equal to 0.19 x 10 to the minus 2nd power/cu Nm) the corrosion rates were low, the kinetics obeyed a parabolic rate equation, and scales consisted mainly of oxide phases

Some studies on a solid state sulfur probe for coal gasification systems

Measurements on the solid electrolyte cell (Ar + H(2) + H(2)S/CaS + CaF(2) + (Pt)//CaF(2)//(Pt) + CaF(2) + CaS/H(2) + H(2)+Ar) show that the emf of the cell is directly related to the difference in sulfur potentials established at the Ar + H(2) + H(2)S/electrode interfaces. The electrodes convert the sulfur potential gradient across the calcium fluoride electrolyte into an equivalent fluorine potential gradient. Response time of the probe varies from approximately 9 hr at 990 K to 2.5 hr at 1225 K. The conversion of calcium sulfide and/or calcium fluoride into calcium oxide is not a problem anticipated in commercial coal gasification systems. Suggestions are presented for improving the cell for such commercial applications

Stability of chromium (III) sulfate in atmospheres containing oxygen and sulfur

The stability of chromium sulfate in the temperature range from 880 K to 1040 K was determined by employing a dynamic gas-solid equilibration technique. The solid chromium sulfate was equilibrated in a gas stream of controlled SO3 potential. Thermogravimetric and differential thermal analyses were used to follow the decomposition of chromium sulfate. X-ray diffraction analysis indicated that the decomposition product was crystalline Cr2O3 and that the mutual solubility between Cr2(SO4)3 and Cr2O3 was negligible. Over the temperature range investigated, the decomposition pressure were significantly high so that chromium sulfate is not expected to form on commercial alloys containing chromium when exposed to gaseous environments containing oxygen and sulfur (such as those encountered in coal gasification)

Using Ciliate Operations to Construct Chromosome Phylogenies

Whole genome sequencing has revealed several examples where genomes of different species are related by permutation. The number of certain types of rearrangements needed to transform one permuted list into another can measure the distance between such lists. Using an algorithm based on three basic DNA editing operations suggested by a model for ciliate micronuclear decryption, this study defines the distance between two permutations to be the number of ciliate operations the algorithm performs during such a transformation. Combining well-known clustering methods with this distance function enables one to construct corresponding phylogenies. These ideas are illustrated by exploring the phylogenetic relationships among the chromosomes of eight fruit fly (Drosophila) species, using the well-known UPGMA algorithm on the distance function provided by the ciliate operations