Spelling suggestions: "subject:"relativistic kinematic""
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Relativistic plane wave description of spin transfer observables for proton knockout reactionsWyngaardt, Shaun Metzler 03 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2001. / ENGLISH ABSTRACT: In this dissertation we set out to develop the first relativistic model for calculating complete
sets of (p, 2p) spin transfer observables. In addition to this a new technique has been developed
which allows us to evaluate the transition amplitude, which is used to calculate the scattering
observables for the reaction directly. The influence of various modiuin-modificd parameters ()1I
the scattered wave functions anr] NN interact ion lH-IVC' })('('11 invest igatcd DlIC t,C) (I,llIlJigllitic's
surrounding the nNN coupling we have included both pseudosoalar and pseudovector coupling
into the nucleon-nucleon interaction model. Furthermore we have included two different kinematic
prescriptions to obtain the effective NN laboratory kinetic energy and center of mass
scattering angle, which are used to obtain the NN scattering amplitudes. The aim of this
study is to investigate the effects of the various model parameters on complete sets of scattering
observables.
Our investigation has shown that although the analyzing power is not very sensitive to nuclear
medium effects, and the various other spin transfer observables such as Dnn should provide
valuable insight. Further refinements of the model would be to include nuclear distortions as
well as the IA2 model of the NN interaction. / AFRIKAANSE OPSOMMING: In hierdie tesis ontwikkel ons die eerste relatiwistiese model vir die berekening van 'n volledige
stel (p, 2p) spin waarneembares. Verder word 'n nuwe tegniek ingevoer wat ons toelaat om die
oorgangsamplitude, wat gebruik word in berekening van die verstrooings waarneembares vir
die reaksie, direk te evalueer. Die invloed van verskeie medium-gemodifiseerde parameters op
die verstrooide golffunksies en die NN wisselwerking word bestudeer. As gevolg van onsekerhede
betreffende die лNN koppeling word beide die pseudoskalaar en pseudovektor koppeling
in die nukleon-nukleon interaksie model ingesluit. Ons sluit ook twee verskillende kinematiese
preskripsies in om die effektiewe NN laboratorium kinetiese energie en die massa middelpunt
verstrooiings hoek, wat gebruik word vir die berekening van die NN verstrooiings amplitude,
te bereken. Die doel van hierdie studie is om die effek van verskeie model parameters op 'n
volledige stel spin waarneembares te ondersoek.
Die studie toon dat alhoewel die analiseervermoë nie baie sensitief is vir medium effekte
nie, die ander spin waarneembares soos byvoorbeeld Dnn waardevolle insig lewer. Daar word
voorgestel dat die model verfyn word deur kerndistorsies as ook die meer algemele IA2 model
vir die NN interaksie in te sluit.
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Neutron Emission Spectrometry for Fusion Reactor Diagnosis : Method Development and Data AnalysisEriksson, Jacob January 2015 (has links)
It is possible to obtain information about various properties of the fuel ions deuterium (D) and tritium (T) in a fusion plasma by measuring the neutron emission from the plasma. Neutrons are produced in fusion reactions between the fuel ions, which means that the intensity and energy spectrum of the emitted neutrons are related to the densities and velocity distributions of these ions. This thesis describes different methods for analyzing data from fusion neutron measurements. The main focus is on neutron spectrometry measurements, using data used collected at the tokamak fusion reactor JET in England. Several neutron spectrometers are installed at JET, including the time-of-flight spectrometer TOFOR and the magnetic proton recoil (MPRu) spectrometer. Part of the work is concerned with the calculation of neutron spectra from given fuel ion distributions. Most fusion reactions of interest – such as the D + T and D + D reactions – have two particles in the final state, but there are also examples where three particles are produced, e.g. in the T + T reaction. Both two- and three-body reactions are considered in this thesis. A method for including the finite Larmor radii of the fuel ions in the spectrum calculation is also developed. This effect was seen to significantly affect the shape of the measured TOFOR spectrum for a plasma scenario utilizing ion cyclotron resonance heating (ICRH) in combination with neutral beam injection (NBI). Using the capability to calculate neutron spectra, it is possible to set up different parametric models of the neutron emission for various plasma scenarios. In this thesis, such models are used to estimate the fuel ion density in NBI heated plasmas and the fast D distribution in plasmas with ICRH.
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