Modeling Simulated Emissions from Galactic Binary Stars

Relativistic plasma flows from the jets of black hole binary systems consist the environment of multiple particle production and radiation emission including neutrinos and gamma-rays. We implement a hadronic model based on $p-p$ interactions with the purpose of predicting the produced secondary particle distributions inside the jet. Our ultimate goal is the neutrino and gamma-ray intensities calculation while taking into account the most important gamma-ray absorption processes in order to present more realistic results.Comment: 6 pages, 6 figure

Charged Particle in an Electromagnetic Field Using Variational Integrators

In the present work we extend the discrete Lagrangian integrator method presented in Ref. [1] to derive appropriate numerical maps for the solution of mechanical problems in which the potential energy depends on the velocity of the system. As a representative concrete example and simulated experiment of the method presented here, we examine the motion of a charged particle moving in an electromagnetic field

Phase fitted variational integrators using interpolation techniques on non regular grids

The possibility of deriving a high order variational integrator that utilizes intermediate nodes within one time interval time to approximate the action integral is investigated. To this purpose, we consider time nodes chosen through linear or exponential expressions and through the roots of Chebyshev polynomial of the first kind in order to approximate the configurations and velocities at those nodes. Then, by defining the Lagrange function as a weighted sum over the discrete Lagrangians corresponding to the curve segments, we apply the phase fitted technique to obtain an exponentially fitted numerical scheme. The resulting integrators are tested for the numerical simulation of the planar two body problem with high eccentricity and of the three-body orbital motion within a solar system

Using simulated annealing algorithms to solve the Schrödinger equation in muonic atoms

In many physical problems, the computation of exact wave functions for muons (particles about two hundred times heavier than electrons), bound in the extended Coulomb field created by the atomic nucleus, is required. Even though the problem is trivial under the assumption of point-like nuclear systems, the consideration of the nuclear finite-size necessitates the use of advantageous numerical techniques. In the case of non-relativistic bound muons, the solution of the Schrödinger equation is reliable, but for a relativistic description the solution of the Dirac equations for the bound muon is needed. In the present contribution, as a first step, we attempt to derive a method for solving the Schrödinger equation on the basis of simulated annealing algorithms. To this end, one may optimize appropriate parametric expressions for the wave function of a muon orbiting around complex nuclei by employing the simulated annealing method recently constructed to minimize multi parametric expressions in several physical applications

Deriving numerical techniques with zero phase-lag and derivatives for initial value problems of second order

In the present we investigate the advantages of the phase lag analysis for the derivation of phase-fitted techniques on several numerical schemes. Relying on the main characteristics of the phase lag we evaluate the parameters needed firstly for Runge-Kutta methods and secondly for high order variational integration methods, so that the phase lag and its derivatives are zero. The proposed methods are tested for the solution of initial value problems on ordinary differential equations of second order, like the Hénon-Heiles model