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131	Deep Minima and Vortices for Positronium Formation in Positron-Hydrogen and Positron-Helium Collisions Alrowaily, Albandari Wanes 05 1900 (has links) This dissertation work is a study of positronium formation for positron-hydrogen and positron-helium collisions in the Ore gap (the energy region between the threshold for ground-state positronium formation and the first excitation level of the target atom) using variational K-matrices. We have fitted the K-matrices using multichannel effective range theories and using polynomials. Using the variational K-matrices and their fits, we have located zeros in the positronium-formation scattering amplitude and corresponding deep minima in the positronium-formation differential cross section. The zeros are related to the vortices in the extended velocity field associated with the positronium-formation scattering amplitude. For positron-hydrogen collisions, we have found two zeros in the positronium-formation scattering amplitude, and corresponding deep minima in the positronium-formation differential cross section, while we have obtained a zero in the positronium-formation scattering amplitude for positron-helium collisions. We have connected the zeros in the positronium-formation scattering amplitude to vortices in the extended velocity fields. Our work shows that vortices can occur for charge exchange in atomic collisions. positron collisions vortices positronium charge exchange
132	All-electron and full-potential positron annihilation calculations for intrinsic and defective zinc and zinc oxide Zhou, Taojun. January 2007 (has links) Thesis (Ph. D.)--University of Hong Kong, 2008. / Also available in print.
133	PET in heart failure : methods and applications / Sörensen, Jens, January 2004 (has links) Diss. (sammanfattning) Uppsala : Univ., 2004. / Härtill 4 uppsatser.
134	Synthesis of ¹¹C-labelled alkyl iodides : using non-thermal plasma and palladium-mediated carbonylation methods / Eriksson, Jonas, January 2006 (has links) Diss. (sammanfattning) Uppsala : Uppsala universitet, 2006. / Härtill 5 uppsatser.
135	Use of the Polaris Vicra for monitoring subject head movement during neurological PET scans Woch, Katherine M. January 1900 (has links) Thesis (M.Sc.). / Written for the Medical Physics Unit. Title from title page of PDF (viewed 2008/01/16). Includes bibliographical references.
136	Positron annihilation spectroscopic studies of GAAS and INP related systems / Ling, Chi-chung, Francis. January 1996 (has links) Thesis (Ph. D.)--University of Hong Kong, 1996. / Includes bibliographical references (leaf 217-227).
137	A study of GaAs and CdZnTe by positron annihilation spectroscopy / Shan, Yueyue. January 1997 (has links) Thesis (Ph. D.)--University of Hong Kong, 1998. / Includes bibliographical references (leaves 128-139).
138	The development of positron deep level transient spectroscopy using variable energy positron beam and conventional deep level transient spectroscopy using digital capacitance meter / Zhang, Jingdong. January 2002 (has links) Thesis (M. Phil.)--University of Hong Kong, 2002. / Includes bibliographical references (leaves 117-121).
139	A positron-probe system for arterial input function quantification for positron emission tomography a dissertation / Lee, Kihak. January 2008 (has links) Dissertation (Ph.D.) --University of Texas Graduate School of Biomedical Sciences at San Antonio, 2008. / Vita. Includes bibliographical references.
140	A study of hadronisation in e[positive]e[negative] annihilation at the Z[superscript degree] using K[superscript degree] mesons. Pouladdej, Ali, Carleton University. Dissertation. Physics. January 1992 (has links) Thesis (Ph. D.)--Carleton University, 1992. / Also available in electronic format on the Internet.

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