Guidance, flight mechanics and trajectory optimization. Volume 6 - The N-body problem and special perturbation techniques

Analytical formulations and numerical integration methods for many body problem and special perturbative technique

The application of generalized, cyclic, and modified numerical integration algorithms to problems of satellite orbit computation

Generalized, cyclic, and modified multistep numerical integration methods are developed and evaluated for application to problems of satellite orbit computation. Generalized methods are compared with the presently utilized Cowell methods; new cyclic methods are developed for special second-order differential equations; and several modified methods are developed and applied to orbit computation problems. Special computer programs were written to generate coefficients for these methods, and subroutines were written which allow use of these methods with NASA's GEOSTAR computer program

Phenomenology of the Standard Model, and beyond, at high-energy colliders

I review planned searches for the so far unobserved Higgs boson of the Standard Model of High Energy Physics. In particular a light 'intermediate' mass Higgs with mass in the range 80 GeV ≤ M(_H) ≤130 GeV will be hard to detect. I suggest several methods at planned future high energy particle colliders for observing this Higgs boson. At LEP I we have reasonable numbers of Higgs produced in association with a Z boson up to the limit imposed by phase space M(_H) ˂ √s - 100 GeV. Unfortunately if the Higgs is degenerate in mass with the Z boson we have large numbers of background events from double Z production. I investigate possible methods round this background. Firstly in polarizing the initial e+e- beams, and secondly in studying the differing topologies of the ZH signal, and ZZ background events. Moving on to the hadron super colliders the LHC and the SSC. These colliders typically produce very clean signals for 'heavy' Higgs. However for a light "'intermediate* mass Higgs all Higgs decays are either dominated by huge QCD backgrounds; or put very strong constraints upon our experimental apparatus. I investigate the signals and backgrounds for an alternative approach where rather than looking for the Higgs in isolation, we look for it produced in association with other heavy particles. Despite these production mechanisms having a far lower rate than isolated Higgs production they have far better signal to background ratios, which makes them look promising. Two modes in particular appear to give encouraging signals; WH production, and tiH production. Both these production modes can be detected in the isolated lepton and two photon channel

Modelling FX smile : from stochastic volatility to skewness

Imperial Users onl

Numerical approximation of boundary conditions with applications to inviscid equations of gas dynamics

A comprehensive overview of the state of the art of well-posedness and stability analysis of difference approximations for initial boundary value problems of the hyperbolic type is presented. The applicability of recent theoretical development to practical calculations for nonlinear gas dynamics is examined. The one dimensional inviscid gas dynamics equations in conservation law form are selected for numerical experiments. The class of implicit schemes developed from linear multistep methods in ordinary differential equations is chosen and the use of linear extrapolation as an explicit or implicit boundary scheme is emphasized. Specification of boundary data in the primitive variables and computation in terms of the conservative variables in the interior is discussed. Some numerical examples for the quasi-one-dimensional nozzle are given

Scattering of electromagnetic waves by two- and three-dimensional dielectric bodies

Imperial Users onl

Use of a moments method for the analysis of flux distributions in subcritical assemblies

Statement of responsibility on title-page reads: H.S. Cheng, I. Kaplan, T.J. Thompson, M.J. Driscoll"MIT-2344 -11."Includes bibliographical references (pages 347-352)A moments method has been developed for the analysis of flux distributions in subcritical neutron-multiplying assemblies. The method determines values of the asymptotic axial and radial buckling, and of the extrapolated height and radius, from foil activation data, in terms of flux moments defined in the usual sense. Analytic expressions are derived for the axial and radial buckling and extrapolated dimensions in terms of the flux moments. These expressions have clear physical meaning and are suitable for the interpretation of conventional buckling measurements. The method treats the moment index as a variable parameter and allows freedom in the choice of the locations of the first and last data points used in the analysis. These degrees of freedom make it possible to reduce the effects of source neutrons, flux transients, and higher harmonics. As a result, the moments method can be applied successfully to very small lattices ("miniature lattices") as well as to large exponential assemblies. The moments method has been tested, in comparison with the conventional least-squares curve-fitting method, by applying the two methods to the analysis of measurements made in several uranium heavy water, and uranium oxide-heavy water lattices investigated at the M. I. T. Lattice Project. In the case of large exponential assemblies, the moments method yielded more consistent results than the curve-fitting method. In the case of miniature lattices, the moments method made it possible for the first time to determine values of axial and radial buckling and extrapolated dimensions.U.S. Atomic Energy Commission contract AT(30-1) 234

The analysis of eclipsing binary systems

Thesis (M.A.)--University of Kansas, Physics and Astronomy, 1956

Algorithms for the solution of systems of coupled second order ordinary differential equations

The close-coupling approximation method involves the numerical solution of systems of coupled second order ordinary differential equations. The solutions can display instability which is made apparent by dependence of the resonance energy on H (step-size). This instability has been examined and corrected. The comparative efficiency, time-wise and storage-wise, of a number of algorithms for the integration of the system of equations is presented.<p

Ultra-cold collisions of identcial atoms

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 1995.Includes bibliographical references (p. 455-461).by Joseph Noël Robin Côté.Ph.D