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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

A STUDY OF HELIUM-4 AND HELIUM-3 PARTICLES EMITTED FROM EXCITED STATES OFBERYLLIUM-7 AND BERYLLIUM-8

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 24-01, page: 0345. / Thesis (Ph.D.)--The Florida State University, 1963.
112

ENERGY LEVELS OF DEFORMED ODD-A NUCLEI

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 24-01, page: 0345. / Thesis (Ph.D.)--The Florida State University, 1963.
113

VARIATIONAL CALCULATIONS ON THE BINDING ENERGY OF THE ALPHA-PARTICLE WITHA HARD CORE POTENTIAL AND A VELOCITY-DEPENDENT POTENTIAL

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 24-01, page: 0345. / Thesis (Ph.D.)--The Florida State University, 1963.
114

FINAL STATE PION-NUCLEON INTERACTIONS AT 2.27 BEV

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 25-12, page: 7337. / Thesis (Ph.D.)--The Florida State University, 1964.
115

FINE STRUCTURE NEAR ISOBARIC ANALOGUE RESONANCES

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 25-12, page: 7339. / Thesis (Ph.D.)--The Florida State University, 1964.
116

THE REACTIONS CARBON-12(HELIUM-3,HELIUM-3)CARBON-12 AND CARBON-12(HELIUM-3,DEUTERON)NITROGEN-13, 12 TO 19 MEV

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 28-11, Section: B, page: 4707. / Thesis (Ph.D.)--The Florida State University, 1967.
117

A POLARIZED LITHIUM-6 SOURCE AND A STUDY OF POLARIZATION EFFECTS IN THE SCATTERING OF HYDROGEN-3 AND LITHIUM-6 (HEAVY IONS)

Unknown Date (has links)
A source for producing beams of vector polarized ('6)Li nuclei has been constructed and tested. The negative ion source is based on the atomic beam technique for selectively populating hyperfine spin states in a beam of ('6)Li atoms. Metallic ('6)Li is formed into a supersonic beam by heating the separated isotope in an oven and extracting the beam through a Laval nozzle and heated collimators. The electronic states are separated in a permanently magnetized sextupole magnet and the nuclei are polarized by a radio frequency transition. The polarized beam is ionized on a hot tungsten strip and converted to a negatively charged beam in a cesium charge exchange canal. The spin axis is rotated by a Wien filter and accelerated by an electrostatic tandem accelerator to energies of up to 6 MeV/nucleon. The beam has been focussed into a new rotatable scattering chamber system where the beam polarization has been measured using a helium gas polarimeter. / The second part of this study is an analysis of polarized triton scattering from ('12)C at 9, 11, 15, and 17 MeV. Through the use of microscopic central and spin-orbit potentials, it is found that a simple spin-orbit description of the spin dependence of the interaction is insufficient to describe the data. A more detailed investigation of possible resonances and channel coupling effects is necessary in order to better understand this system at these energies. / The last part of this study is an investigation of the spin dependence of ('6)Li + ('16)O scattering at 22.8 MeV. Excitation function data for the elastic channel and the inelastic strength of the ('6)Li first excited state were measured to complement previously measured elastic cross section and analyzing power data for this system. The vector analyzing powers show a much greater sensitivity to coupled-channels and resonance effects than the cross section. It is only when the channel coupling to the projectile excitation channel is combined with a spin-orbit potential that the analyzing power data can be described. However, more analyzing power data is needed to resolve the sources of the spin dependence of this system. / Source: Dissertation Abstracts International, Volume: 48-01, Section: B, page: 0171. / Thesis (Ph.D.)--The Florida State University, 1986.
118

THE KAON-NUCLEON INTERACTION IN A QUARK POTENTIAL MODEL (HADRON)

Unknown Date (has links)
The K('+)-N interaction is calculated with a quark potential model using the resonating group method (RGM). For the central interaction 2(H/2PI)(omega) mixed symmetry components of the nucleon and 2(H/2PI)(omega) components of the kaon wave function are included in the calculation of the RGM kernels. The total isospin I = 0 s-wave phase shifts are in good agreement with the experimentally determined phase shifts. The I = 1 interaction does not exhibit enough repulsion. The K('+)*-N channel is coupled to the K('+)-N channel via quark exchange. The channel coupling gives effectively a more repulsive interaction for both I = 1 and I = 0. This is in qualitative agreement with the I = 0 phase shifts above threshold. The spin-orbit quark exchange potential is calculated and found to be much weaker than a phenomenological potential which reproduces the p-wave phase shifts. / Source: Dissertation Abstracts International, Volume: 47-06, Section: B, page: 2487. / Thesis (Ph.D.)--The Florida State University, 1986.
119

HEAVY ION RESONANCES IN THE CARBON-12 + CARBON-12 SYSTEM

Unknown Date (has links)
Heavy ion resonances in the ('12)C + ('12)C system were investigated with an optical model plus multi-level resonance (OMMR) analysis. Elastic scattering excitation function cross sections were measured for 12 angles between 17.1(DEGREES) and 90.0(DEGREES) for energies between 17.5 Mev and 21.5 Mev in 100 keV intervals (in the center of mass system). The total reaction cross section data were measured at intervals of 100 keV for energies between 17.5 and 21.5 MeV. Analysis of the elastic scattering data including cross section data measured at six angles corresponding to zeros of Legendre polynomials provided spin determinations for four resonances located at 18.2, 19.2 and 20.2 MeV. The resonances at 18.2 and 19.2 MeV were determined to have spins = 12. The two resonances located at 20.2 MeV were determined to have spins of 12 and 14. / For the OMMR analysis, four resonance terms were added to a smoothly varying background which was described by the optical model. The optical model potential which best described the elastic scattering cross section data and the total reaction cross section data had a Woods-Saxon squared real plus Woods-Saxon imaginary form. Several other common potential forms were tested but they resulted in a poorer description of the data. The background absorption for the L = 12 partial wave at 19.2 MeV, which was calculated using the parameters obtained from the elastic scattering analysis, lead to an L = 12 partial wave which was nearly fully absorbed. However, comparisons of the calculated total reaction cross section with the data indicates that the background absorption must be considerably smaller than this. / Source: Dissertation Abstracts International, Volume: 48-03, Section: B, page: 0801. / Thesis (Ph.D.)--The Florida State University, 1987.
120

Charge dependence of the nucleon-nucleon interaction in a quark model

Unknown Date (has links)
The charge dependence (isospin symmetry breaking) of the nucleon-nucleon interaction is examined with a nonrelativistic quark model. The model is extended to include charge dependent effects arising from the up-down quark mass difference, the neutral-charged pion mass difference, and from the neutron-proton mass difference. The one-photon exchange potential is also included to the order of the inverse nucleon mass squared. / The deuteron is treated in order to acquire some idea of the values that the model parameters may assume. No signature of charge dependence is seen in this system. / The A = 3 systems are also considered. Here it is found that the kinetic energy difference of the up and down quarks due to their differing masses gives rise to a potential that depends on the isospin projection of the two nucleons. An estimate is made for the binding energy difference between the mirror A = 3 nuclei due to this potential; on the order of sixty percent of the Nolen-Schiffer anomaly can be accounted for with this effect. / For the nucleon-nucleon scattering systems, scattering lengths and effective ranges are calculated. The charge dependent pionic interaction is found responsible for the bulk of the discrepancy between the scattering length of the neutron-proton system relative to those of the (Coulomb corrected) proton-proton or neutron-neutron systems. The potential that arises from the quark kinetic energy difference gives a contribution to the proton-proton and neutron-neutron scattering length difference that is of the correct sign and magnitude in comparison to the data. / Distorted wave Born approximation (DWBA) calculations are performed to determine the neutron-proton analyzing power differences that arise from class IV isospin dependent interactions. Results are given as a function of center of mass scattering angle at several energies. The results show that certain angles and energies exist at which some contributions to the analyzing power difference vanish, leaving one dominant contribution remaining. Hence it may prove possible to isolate this contribution and gain some insight into the nucleon-nucleon interaction from a particular class IV effect. / Source: Dissertation Abstracts International, Volume: 49-03, Section: B, page: 0803. / Major Professor: Donald Robson. / Thesis (Ph.D.)--The Florida State University, 1987.

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