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41 
Energy transfer in collisions of small moleculesPetty, Frederick Cecil 05 1900 (has links)
No description available.

42 
Equilibria and hadron multiplicities in heavyion collisionsMaso, A. C. P. January 1984 (has links)
The intranuclear cascade is an approximate microscopic model of heavyion collisions in which the spacetime evolution of the nucleons is followed as they collide with one another. This model is used: (a) to test the validity of simpler models as the twofireball model; (b) to estimate the validity of the assumption of chemical equilibrium and to calculate the total pion production crosssections; (c) to investigate the average primordial charge multiplicity and the number of participants as a function of the beam energy.

43 
Ionization cross sections for protons incident on helium, neon, argon, hydrogen, nitrogen, oxygen, and carbon monoxide in the energy range 015110 MevHooper, John William 08 1900 (has links)
No description available.

44 
Numerical simulations of high speed droplet collisionBlancher, Roman Adrien 05 1900 (has links)
No description available.

45 
An L² representation of the continuum in heavy particle collisionsHewitt, Robin Nicholas January 1987 (has links)
This thesis is concerned with the use of L² or square integrable functions as a representation of the electronic continua in ionatom collisions. An exact representation of the continuum states is considered for comparison. The functions are optimised in an attempt to remove some of the arbitrary features present in such calculations. The original work of this thesis is mainly concerned with the calculation of single electron processes in collisions between He²⁺ ions and neutral lithium atoms. The cross sections for single electron capture were calculated in a closecoupled approximation, using the semiclassical impact parameter method. A maximum of thirtytwo atomic orbitals with planewave translational factors attached were centred upon the target and projectile. Satisfactory agreement with experimental data is obtained over the He(^2+)laboratory energy range from 8 to 2000 keV. The results show the importance of the continuum over a restricted range of impact energies. The rest of the research is concerned with direct excitation and ionisation in the same collision system and results are given for He²⁺ laboratory energies between 20 and 6000 keV. The calculations used a similar closecoupled approximation with up to sixtyfive basis states. The best ionisation cross sections reproduce the experimental data apart from a normalization factor. The excitation results were more sensitive to basis set choice. The ionisation cross sections were also investigated using an exact representation of the continuum states, using the First Born Approximation and a tmatrix approximation in an attempt to improve upon the L² results. The relationship between the present calculations and some previous methods are discussed and suggestions for future work are made. These are the first closecoupled estimates of ionisation for this sytem and show that contributions from target d and f states dominate the ionisation cross section around its maximum.

46 
Charge transfer and ionisation in collisions between positive ionsWatts, Mark Frederick January 1986 (has links)
No description available.

47 
Quantum chromodynamics and the production of hadrons at large transverse momentumPapadopoulos, Stavros January 1979 (has links)
No description available.

48 
Convergent CloseCoupling Calculations of PositronHelium CollisionsHuayou Wu January 2004 (has links)
The Convergent Close Coupling (CCC) method is applied, for the first time, to the scattering of positrons on helium. The helium target wave functions are obtained within various configuration interaction (CI) expansions. In the full CI expansion the two electrons are treated equally and thus all electronelectron correlations are taken into account. In the frozencore (FC) approximation the CI expansion fixes one of the electrons to be described by a pure 1s orbital of He+, while maintaining the required singlet and triplet symmetries. Lastly, the multiconfiguration (MC) approximation relaxes the FC approximation to allow the description of the inner electron to include several lowlying orbitals and is therefore more accurate than the FC approximation. The accuracy of the target wave functions is tested by comparing the calculated energy levels with the experimental data.
Based on positronhydrogen scattering, comprehensive closecoupling formulas for positronhelium scattering are developed. The reduced twocentre Vmatrix elements are derived in momentum space for various channels. These include direct, excitation and rearrangement channels, i.e. positronium formation.
We first consider low energy positronhelium elastic scattering for energies below the positronium formation threshold of 17.8 eV. Utilizing a singlecentre expansion the elastic cross section and phase shifts have been calculated as a function of the positron incident energy. The calculations agree very well with the experimental data and the variational calculations, but not previous single or doublecentre closecoupling calculations.
We then consider energies above the first ionization threshold (24.6 eV) and calculate helium elastic, excitation, fragmentation and total cross sections within the singlecentre expansion approach. Good agreement with the available experimental and other theoretical results has been obtained.
The studies have proved that a singlecentre expansion, with accurate target state description, can deliver accurate data of practical value over a broad range of energies. However in the lowenergy region, between the positronium formation threshold of 17.8 eV and the ionization threshold of 24.6 eV, implementation of the twocentre expansion is required. We expect this work to be undertaken in the near future, based on the derivations presented in this thesis.

49 
Analyses of ship collisions determination of longitudinal extent of damage and penetration /Sajdak, John Anthony Waltham, January 2004 (has links)
Thesis (Ph. D.)Virginia Polytechnic Institute and State University, 2004. / Vita. Abstract. Includes bibliographical references (p. 234243).

50 
Liquid and solid impact studies including hypervelocities a literature survey /Pitek, Martin T. January 1900 (has links)
Thesis (M.S.)University of Michigan, 1966.

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