321,594 research outputs found
Revisiting the hot matter in the center of gamma-ray bursts and supernova
Hot matter with nucleons can be produced in the inner region of the
neutrino-dominated accretion flow in gamma-ray bursts or during the
proto-neutron star birth in successful supernova. The composition and equation
of state of the matter depend on the dynamic equilibrium under various
neutrino opacities. The strong interaction between nucleons may also play an
important role. We plan to extend the previous studies by incorporating these
two aspects in our model. The modification of the -equilibrium condition
from neutrino optically thin to thick has been modeled by an equilibrium factor
ranging between the neutrino-freely-escaping case and the
neutrino-trapped case. We employ the microscopic Brueckner-Hartree-Fock
approach extended to the finite temperature regime to study the interacting
nucleons. We show that the composition and chemical potentials of the hot
nuclear matter for different densities and temperatures at each stage of
equilibrium. We also compare our realistic equation of states with
those of the free gas model. We find the neutrino opacity and the strong
interaction between nucleons are important for the description and should be
taken into account in model calculations.Comment: accepted Astronomy & Astrophysics (2013
The Hahn Quantum System
Using a formulation of quantum mechanics based on the theory of orthogonal
polynomials, we introduce a four-parameter system associated with the Hahn and
continuous Hahn polynomials. The continuum energy scattering states are written
in terms of the continuous Hahn polynomial whose asymptotics give the
scattering amplitude and phase shift. On the other hand, the finite number of
discrete bound states are associated with the Hahn polynomial.Comment: 18 pages, 7 figure
Fluctuation limits of strongly degenerate branching systems
Functional limit theorems for scaled fluctuations of occupation time
processes of a sequence of critical branching particle systems in with
anisotropic space motions and strongly degenerated splitting abilities are
proved in the cases of critical and intermediate dimensions. The results show
that the limit processes are constant measure-valued Wienner processes with
degenerated temporal and simple spatial structures.Comment: 15 page
A Two-Tiered Correlation of Dark Matter with Missing Transverse Energy: Reconstructing the Lightest Supersymmetric Particle Mass at the LHC
We suggest that non-trivial correlations between the dark matter particle
mass and collider based probes of missing transverse energy H_T^miss may
facilitate a two tiered approach to the initial discovery of supersymmetry and
the subsequent reconstruction of the LSP mass at the LHC. These correlations
are demonstrated via extensive Monte Carlo simulation of seventeen benchmark
models, each sampled at five distinct LHC center-of-mass beam energies,
spanning the parameter space of No-Scale F-SU(5).This construction is defined
in turn by the union of the Flipped SU(5) Grand Unified Theory, two pairs of
hypothetical TeV scale vector-like supersymmetric multiplets with origins in
F-theory, and the dynamically established boundary conditions of No-Scale
Supergravity. In addition, we consider a control sample comprised of a standard
minimal Supergravity benchmark point. Led by a striking similarity between the
H_T^miss distribution and the familiar power spectrum of a black body radiator
at various temperatures, we implement a broad empirical fit of our simulation
against a Poisson distribution ansatz. We advance the resulting fit as a
theoretical blueprint for deducing the mass of the LSP, utilizing only the
missing transverse energy in a statistical sampling of >= 9 jet events.
Cumulative uncertainties central to the method subsist at a satisfactory 12-15%
level. The fact that supersymmetric particle spectrum of No-Scale F-SU(5) has
thrived the withering onslaught of early LHC data that is steadily decimating
the Constrained Minimal Supersymmetric Standard Model and minimal Supergravity
parameter spaces is a prime motivation for augmenting more conventional LSP
search methodologies with the presently proposed alternative.Comment: JHEP version, 17 pages, 9 Figures, 2 Table
Property-Based Testing - The ProTest Project
The ProTest project is an FP7 STREP on property based testing. The purpose of the project is to develop software engineering approaches to improve reliability of service-oriented networks; support fault-finding and diagnosis based on specified properties of the system. And to do so we will build automated tools that will generate and run tests, monitor execution at run-time, and log events for analysis.
The Erlang / Open Telecom Platform has been chosen as our initial implementation vehicle due to its robustness and reliability within the telecoms sector. It is noted for its success in the ATM telecoms switches by Ericsson, one of the project partners, as well as for multiple other uses such as in facebook, yahoo etc. In this paper we provide an overview of the project goals, as well as detailing initial progress in developing property based testing techniques and tools for the concurrent functional programming language Erlang
Investigation to define the propagation characteristics of a finite amplitude acoustic pressure wave, phase 1 final report, 29 jun. 1964 - 29 jul. 1965
The contribution of high entropy production regions to the generation and propagation characteristics of a finite amplitude pressure is considered. Preliminary analysis indicates that, for nozzles where pressure rations are above critical, the predominant contribution may come from the shock layer formation in the exhaust region. Temperature effects indicate high dependence of the forcing function upon the initial temperature of the media
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