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Full-Text Articles in Physics
Energy Spread And Ion Current Measurements Of Several Ion Sources, A. D. Gaus, W. T. Htwe, J. A. Brand, Timothy J. Gay, M. Schulz
Energy Spread And Ion Current Measurements Of Several Ion Sources, A. D. Gaus, W. T. Htwe, J. A. Brand, Timothy J. Gay, M. Schulz
Timothy J. Gay Publications
Energy spread and extracted current measurements are presented for five different types of ion sources: hot cathode, cold cathode, magnetron, microwave, and electron cyclotron resonance (ECR). The measurements were performed with a 45° parallel-plate energy analyzer with a resolution of better than 0.5 eV at 500 eV incident energy. Energy spreads ranged from 0.5 to 4 eV, while total extracted beam currents ranged from 2 to 30 μA. Beam currents due specifically to protons, 3He++ ions, and H+2 ions are also presented. The ECR and magnetron sources gave the best overall performance. These, along with the …
Clean Ultrahigh Vacuum System With Single-Structure Diffusion Pumps, Timothy J. Gay, M.C. Fritts, J.E. Furst, M.A. Khakoo, E.R. Mell, M.T. Seiger, M.W.K.P. Wijayaratna
Clean Ultrahigh Vacuum System With Single-Structure Diffusion Pumps, Timothy J. Gay, M.C. Fritts, J.E. Furst, M.A. Khakoo, E.R. Mell, M.T. Seiger, M.W.K.P. Wijayaratna
Timothy J. Gay Publications
A practical example of the use of single-structure diffusion pumping groups in an experiment requiring hydrocarbon-free, ultrahigh vacuum is presented. With the use of proper vacuum procedures and careful foreline design and operation, but with no exotic hardware or liquid nitrogen, we have demonstrated that such a pump could provide vacuum that was "clean," i.e., which had no residual pump-oil contamination to a partial pressure below 10-8 mbar. Their use is thus compatible, at least in peripheral vacuum chambers, with standard "UHV-surface science" processes. We discuss our vacuum system in detail, and present a review of the literature on …
Clean Ultrahigh Vacuum System With Single-Structure Diffusion Pumps, Timothy J. Gay, M.C. Fritts, J.E. Furst, M.A. Khakoo, E.R. Mell, M.T. Seiger, M.W.K.P. Wijayaratna
Clean Ultrahigh Vacuum System With Single-Structure Diffusion Pumps, Timothy J. Gay, M.C. Fritts, J.E. Furst, M.A. Khakoo, E.R. Mell, M.T. Seiger, M.W.K.P. Wijayaratna
Timothy J. Gay Publications
A practical example of the use of single-structure diffusion pumping groups in an experiment requiring hydrocarbon-free, ultrahigh vacuum is presented. With the use of proper vacuum procedures and careful foreline design and operation, but with no exotic hardware or liquid nitrogen, we have demonstrated that such a pump could provide vacuum that was "clean," i.e., which had no residual pump-oil contamination to a partial pressure below 10-8 mbar. Their use is thus compatible, at least in peripheral vacuum chambers, with standard "UHV-surface science" processes. We discuss our vacuum system in detail, and present a review of the literature on the …
Superelastic And Inelastic He2++He State-Selective Electron Capture, V. D. Irby, Timothy J. Gay, J. T. Park, S. W. Bross, A. D. Gaus
Superelastic And Inelastic He2++He State-Selective Electron Capture, V. D. Irby, Timothy J. Gay, J. T. Park, S. W. Bross, A. D. Gaus
Timothy J. Gay Publications
Experimental studies have been made of superelastic and inelastic collision processes involved in the state-selective single-electron capture reaction 3He2++He(1 1S)→ +He+(n)+He+(n’), where n and n’ are the final principal quantum-number states of the collision products. Total cross sections have been measured at projectile energies of 15, 30, and 45 keV/u, by examining the energy loss-gain of the fast 3He+ product ions, for the superelastic n=n’=1 channel, and for the sum of the inelastic n=2, n’=1 and n=1, n’=2 states. Measurements …