No description available.

The Canadian Penning Trap Mass Spectrometer (CPTMS) located at the ATLAS (Argonne Tandem Linear Accelerator System) facility of Argonne National Laboratory makes precise mass measurements on both stable and unstable isotopes. A 252Cf fission source has been used as the ion source for the unstable isotope mass measurements. This thesis concentrates on the mass measurements of the fission fragments from the 252Cf fission source using the CPTMS system. It is the first time that the masses of such fission fragments have been measured with a mass spectrometer. The masses of 108Tc, 108Ru, 109Ru and 110Ru have been measured to a precision of 10-7. The results have been compared to exiting mass measurements and the Atomic Mass Evaluation (AME2003). In general good agreement between this work and existing data is realized. A few discrepancies are identified. / October 2006

The Canadian Penning Trap Mass Spectrometer (CPTMS) located at the ATLAS (Argonne Tandem Linear Accelerator System) facility of Argonne National Laboratory makes precise mass measurements on both stable and unstable isotopes. A 252Cf fission source has been used as the ion source for the unstable isotope mass measurements. This thesis concentrates on the mass measurements of the fission fragments from the 252Cf fission source using the CPTMS system. It is the first time that the masses of such fission fragments have been measured with a mass spectrometer. The masses of 108Tc, 108Ru, 109Ru and 110Ru have been measured to a precision of 10-7. The results have been compared to exiting mass measurements and the Atomic Mass Evaluation (AME2003). In general good agreement between this work and existing data is realized. A few discrepancies are identified.

The Canadian Penning Trap Mass Spectrometer (CPTMS) located at the ATLAS (Argonne Tandem Linear Accelerator System) facility of Argonne National Laboratory makes precise mass measurements on both stable and unstable isotopes. A 252Cf fission source has been used as the ion source for the unstable isotope mass measurements. This thesis concentrates on the mass measurements of the fission fragments from the 252Cf fission source using the CPTMS system. It is the first time that the masses of such fission fragments have been measured with a mass spectrometer. The masses of 108Tc, 108Ru, 109Ru and 110Ru have been measured to a precision of 10-7. The results have been compared to exiting mass measurements and the Atomic Mass Evaluation (AME2003). In general good agreement between this work and existing data is realized. A few discrepancies are identified.

The Canadian Penning Trap (CPT) mass spectrometer at the Argonne National Laboratory makes precise mass measurements of both stable and unstable nuclides. To date, more than 60 radioactive isotopes having half-lives as short as one second have been measured with the CPT with a mass precision approaching 10 ppb. This thesis will present measurements made of nuclides along the rp-process path, which describes a process resulting from a series of rapid proton-capture reactions in an astrophysical environment. One possible site for the rp-process mechanism is an x-ray burst which results from the rapid accretion of hydrogen and helium from one star onto the surface of its neutron star binary companion. Mass measurements are required as key inputs to network calculations used to describe the rp-process in terms of the abundances of the nuclides produced, the light-curve profile of the x-ray bursts, and the energy produced. This thesis will describe the CPT apparatus, explain the method used to make precise mass measurements, and present the masses of the "waiting-point" nuclides ⁶⁸Se and ⁶⁴Ge. The mass measurement results, when used in x-ray burst models, confirm both ⁶⁸Se and ⁶⁴Ge as waiting-point nuclides which delay the rp-process by approximately 30 s and 7 s respectively. / October 2005

No description available.

The Canadian Penning Trap (CPT) mass spectrometer at the Argonne National Laboratory makes precise mass measurements of both stable and unstable nuclides. To date, more than 60 radioactive isotopes having half-lives as short as one second have been measured with the CPT with a mass precision approaching 10 ppb. This thesis will present measurements made of nuclides along the rp-process path, which describes a process resulting from a series of rapid proton-capture reactions in an astrophysical environment. One possible site for the rp-process mechanism is an x-ray burst which results from the rapid accretion of hydrogen and helium from one star onto the surface of its neutron star binary companion. Mass measurements are required as key inputs to network calculations used to describe the rp-process in terms of the abundances of the nuclides produced, the light-curve profile of the x-ray bursts, and the energy produced. This thesis will describe the CPT apparatus, explain the method used to make precise mass measurements, and present the masses of the "waiting-point" nuclides ⁶⁸Se and ⁶⁴Ge. The mass measurement results, when used in x-ray burst models, confirm both ⁶⁸Se and ⁶⁴Ge as waiting-point nuclides which delay the rp-process by approximately 30 s and 7 s respectively.

The Canadian Penning Trap (CPT) mass spectrometer at the Argonne National Laboratory makes precise mass measurements of both stable and unstable nuclides. To date, more than 60 radioactive isotopes having half-lives as short as one second have been measured with the CPT with a mass precision approaching 10 ppb. This thesis will present measurements made of nuclides along the rp-process path, which describes a process resulting from a series of rapid proton-capture reactions in an astrophysical environment. One possible site for the rp-process mechanism is an x-ray burst which results from the rapid accretion of hydrogen and helium from one star onto the surface of its neutron star binary companion. Mass measurements are required as key inputs to network calculations used to describe the rp-process in terms of the abundances of the nuclides produced, the light-curve profile of the x-ray bursts, and the energy produced. This thesis will describe the CPT apparatus, explain the method used to make precise mass measurements, and present the masses of the "waiting-point" nuclides ⁶⁸Se and ⁶⁴Ge. The mass measurement results, when used in x-ray burst models, confirm both ⁶⁸Se and ⁶⁴Ge as waiting-point nuclides which delay the rp-process by approximately 30 s and 7 s respectively.

No description available.

In its first three years of operation, the Large Hadron Collider at CERN has already proved its worth as a discovery machine and reinvigorated the prospects for discovering new dynamics beyond the Standard Model. This thesis presents a range of experimental methods devised for discovery of supersymmetry, one of the most important extensions of the Standard Model being tested at the LHC. The first chapter discusses the concepts behind a set of transverse mass-bound variables, and explores connections between these variables and others in the literature. Not only are these variables important tools for mass measurement, should sparticles be seen at the LHC, they are also critical components of experimental searches. Accordingly, their performance has been compared in both mass measurement and search contexts, and the results are reported here. This is followed by the details of a search for hadronically-decaying squarks and gluinos, carried out on 4.7 fb−1 of data collected at 7 TeV in 2011 by the ATLAS detector. The search strategy is described, focusing on the implementation of a background estimation method using photon events to determine the background contamination due to invisible Z boson decays. The results of the search are then presented. Stringent limits are set on the production of squarks and gluinos in a variety of model scenarios.