Search results for "binary [neutron star]"
showing 10 items of 544 documents
Extropy: Complementary Dual of Entropy
2015
This article provides a completion to theories of information based on entropy, resolving a longstanding question in its axiomatization as proposed by Shannon and pursued by Jaynes. We show that Shannon's entropy function has a complementary dual function which we call "extropy." The entropy and the extropy of a binary distribution are identical. However, the measure bifurcates into a pair of distinct measures for any quantity that is not merely an event indicator. As with entropy, the maximum extropy distribution is also the uniform distribution, and both measures are invariant with respect to permutations of their mass functions. However, they behave quite differently in their assessments…
Spectroscopic Observations of the Delta Scorpii Binary during Its Recent Periastron Passage
2001
The bright star delta Sco has been considered a typical B0-type object for many years. Spectra of the star published prior to 1990 showed no evidence of emission, but only of short-term line profile variations attributed to nonradial pulsations. Speckle interferometric observations show that delta Sco is a binary system with a highly-eccentric orbit and a period of 10.6 years. Weak emission in the H-alpha line was detected in its spectrum for the first time during a periastron passage in 1990. Shortly before the next periastron passage in the summer of 2000, the binary entered a strong H-alpha emission and enhanced mass loss phase. We monitored the spectroscopic development of the Be outbur…
Search for Gravitational-wave Signals Associated with Gamma-Ray Bursts during the Second Observing Run of Advanced LIGO and Advanced Virgo
2019
We present the results of targeted searches for gravitational-wave transients associated with gamma-ray bursts during the second observing run of Advanced LIGO and Advanced Virgo, which took place from 2016 November to 2017 August. We have analyzed 98 gamma-ray bursts using an unmodeled search method that searches for generic transient gravitational waves and 42 with a modeled search method that targets compact-binary mergers as progenitors of short gamma-ray bursts. Both methods clearly detect the previously reported binary merger signal GW170817, with p-values of <9.38 10-6 (modeled) and 3.1 10-4 (unmodeled). We do not find any significant evidence for gravitational-wave signals associate…
Monte Carlo Simulation of Alloy Phase Diagrams and Short-Range Order
1986
As a prototype model for order-disorder phenomena in binary alloys, a face-centered cubic lattice is considered,the sites of which can be taken by either A-atoms or B-atoms, assuming pair-wise interactions between nearest (J) and next nearest neighbours (J). The phase diagram is constructed from Monte Carlo calculations. Some technical aspects essential for the success of such calculations are briefly mentioned (use of grand-canonical rather than canonical ensemble, how to obtain the free energy needed to locate first-order phase transitions, etc.). It is shown that the topology of the phase diagram changes when the ratio R = Jnnn/Jnn is varied, and this behaviour is discussed in the contex…
Anomalous size-dependence of interfacial profiles between coexisting phases of polymer mixtures in thin-film geometry: A Monte Carlo simulation
1997
The interfacial profile between coexisting phases of a binary mixture (A,B) in a thin film of thickness D and lateral linear dimensions L depends sensitively on both linear dimensions and on the nature of boundary conditions and statistical ensembles applied. These phenomena generic for systems in confined geometry are demonstrated by Monte-Carlo simulations of the bond fluctuation model of symmetric polymer mixtures. Both the canonical and semi-grand-canonical ensemble are studied. In the canonical ensemble, the interfacial width w increases (from small values which are of the same order as the intrinsic profile) like sqrt{D}, before a crossover to a saturation value w_max (w_max^2 proport…
Graphical representation of polynuclear acid-base and complex equilibria.
1983
Abstract A calculation procedure for diagrams of log CM = ƒ(pL) at various values of the ratio of analytical concentrations, CL/CM, in polynuclear binary systems is described. The diagrams are useful in the resolution of analytical problems of practical interest involving acid-base equilibria (such as the preparation of buffer solutions) and complex equilibria. The presence of a solid phase is also considered.
Structures and EPR spectra of binary sulfur–nitrogen radicals from DFT calculations
2007
Abstract The scattered electron paramagnetic resonance (EPR) spectroscopic data for binary sulfur–nitrogen (S,N) radicals have been compiled and critically assessed.Many of these are inorganic rings or cages.For each species, possible equilibrium structures in the gas phase and the EPR hyperfine coupling (hfc) constants have been calculated with DFT using the B3LYP functional and basis sets of triple-ζ (or better) quality.Good agreement is obtained between calculated and measured values for the well characterized [S3N2]+ , a planar π-radical for which the s-component of the orbitals is likely to be reasonably independent of minor geometrical changes between gas-phase and condensed-phase sta…
Effect of tetrahydrofuran on the conductance and ion-pairing of hydrogen chloride in wet and dry methanol mixtures
1995
The molar conductance of dilute solutions of HCl in wet (68.5% methanol + 31.5% tetrahydrofurane mixtures at 25°C have been measured. The data were analyzed using the Fuoss-Hsia equation to calculate the infinite dilution molar conductances and association constants. The trend of the limiting conductances in these mixtures as a function of the water content shows, once more, the peculiar minimum due to the anomalous proton conductance mechanism. From these data the limiting molar conductance in the anhydrous binary solvent system was evaluated. The percentage excess proton mobility with respect to potassium ion has also been determined. All these data are compared to those found in a binary…
Peak deconvolution in one-dimensional chromatography using a two-way data approach.
2002
A deconvolution methodology for overlapped chromatographic signals is proposed. Several single-wavelength chromatograms of binary mixtures, obtained in different runs at diverse concentration ratios of the individual components, were simultaneously processed (multi-batch approach), after being arranged as two-way data. The chromatograms were modelled as linear combinations of forced peak profiles according to a polynomially modified Gaussian equation. The fitting was performed with a previously reported hybrid genetic algorithm with local search, leaving all model parameters free. The approach yielded more accurate solutions than those found when each experimental chromatogram was fitted in…
Densities, Viscosities, and Refractive Indices of Some Binary Liquid Systems of Methanol + Isomers of Hexanol at 298.15 K
1996
Viscosities, densities, and refractive indices of eight binary liquid systems containing ethanol + some isomers of hexanol have been determined at 298.15 K. The excess property values were fitted to the Redlich-Kister equation to estimate the binary coefficients and the standard deviations.