Download or read book Search for Resonant States in Positron electron Scattering Using a Positron Gas Target written by and published by . This book was released on 1990 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: Narrow correlated positron-electron peaks discovered in superheavy nuclear collisions may be signatures for previously undetected neutral particle-like objects having masses of 1--2 MeV/c2. We have designed an experiment to definitively test this hypothesis by searching for resonant states formed directly in the scattering of monoenergetic electrons incident on a gas of cold positrons confined magnetically in a Malmberg trap. This technique will provide a hundred-fold improvement in sensitivity to ee− resonances compared to previous positron-beam, thin-foil scattering experiments. Together with a recoil-shadow technique, this experiment will explore a five decade range in neutral-particle lifetimes (10−13s to 10−8s) which cannot be probed directly to other methods. 14 refs., 2 figs., 1 tab.
Download or read book Positron Electron Gas Scattering Proceedings Of The 3rd International Workshop written by Walter E Kauppila and published by World Scientific. This book was released on 1986-04-01 with total page 373 pages. Available in PDF, EPUB and Kindle. Book excerpt: This workshop discusses the current state and future directions of research in positron — gas scattering, particularly in the relationship between positron and electron scattering by the same atoms and molecules. The possible applications of positron — gas scattering to astrophysical phenomena have also been discussed.
Download or read book Positron Scattering in Gases written by John W. Humberston and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first conference in this series, devoted principally to the interaction of positrons in gases, was held at York University, Toronto, in July 1981 immediately preceding the XII ICPEAC in Gatlinburg, and the proceedings were published in the Canadian Journal of Physics, volume 60 (1982). So successful was this meeting that the decision was taken to hold a second one around the time of XIII ICPEAC in Berlin in 1983. London was clearly a convenient location but, rather than the obvious choice of University College London in central London, the Organising Committee decided that the beautiful and peaceful surroundings of Royal Holloway College would provide a more pleasant and intimate atmosphere for a small meeting. Even a small conference requires substantial sums of money to pay the expenses of invited speakers and when considering possible sources of funds the Organising Committee recognised that the intended format of the meeting and the international composition of the participants made it appropriate to apply to the NATO Science Committee for support under the Advanced Research Workshop Programme. This was one of the few successful applications made this year, and so it was that the conference became the 'NATO Advanced Research Workshop on Positron Scattering in Gases'. The Workshop, with approximately sixty participants, started after lunch on 19 July, 1983 and finished at mid-day on 23 July.
Download or read book Energy Research Abstracts written by and published by . This book was released on 1993 with total page 490 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Laboratory Directed Research and Development written by Lawrence Livermore National Laboratory and published by . This book was released on 1990 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings of the Third International Workshop on Positron Electron Gas Scattering Wayne State University Detroit Michigan July 16 18 1985 written by Walter E. Kauppila and published by . This book was released on 1986 with total page 373 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Electron Photon and Positron Scattering Dynamics of Complex Molecular Targets written by Ralph Carey and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Electron scattering cross sections have been computed for pyridine and pyrimidine using the static-exchange approximation with model potential to account for dynamic electron correlation. To obtain well-converged orbitals, we have expanded all partial waves to a maximum angular momentum of l = 60 for both targets. We have obtained total cross sections for electron scattering energies to 20 eV. Both targets display similar features, namely a dipole-induced increase in the integrated cross section at scattering energies below 5 eV, and peaks corresponding to resonances in b1, a2, and b1 symmetries. These resonances were investigated through a Siegert eigenstate analysis and Breit-Wigner fit of the SECP eigenphase sums. They were also compared to the virtual orbitals obtained from a minimum basis set Hartree-Fock calculation on both targets. We consider electron scattering resonances from cis-diamminedichloroplatinum, [Pt(NH3)2Cl2], the ligand molecular species Cl2 (1Sigma+g), and the isolated transition metal center Pt in a nondegenerate atomic state (1S) at the SECP level of theory. As a rigorous comparison to the single-state, single-configuration SECP level results of these smaller, yet electron dense targets, we have also considered scattering from ground state Cl2 and Pt in the 1S and 3D states in the multichannel configuration-interaction (MCCI) approximation originally developed for photoionization for scattering up to 10 eV. Photoionization cross sections and angular distributions in the recoil frame (RFPAD) and molecular frame (MFPAD) have been computed for inner-shell C 1s and Cl 2p ionization from the chloroalkanes chloromethane and chloroethane, with ionization leading to a variety of ionic fragment states. We have also computed valence level ionization from the nitro molecule nitromethane CH3NO2 leading to the dissociation of the CN bond. All of these calculations were performed in the frozen-core Hartree-Fock approximation. Even at this level of theory, we obtain computed results that compare well to the photoelectronphotoion coincidence measurements. The fullerene C20 is the smallest fullerene predicted to exist, with most relevant structural calculations suggesting the reduction of the icosahedral symmetry into one in which the target species possesses at maximum only a dihedral axis. We have computed positron scattering cross sections for the molecule in two low-symmetry structural isomers Ci and C2, within the HF approximation. Density functional expressions were used to incorporate important positron-electron interactions within the calculation. We have found similar cross sections and resonance features for both isomers, including a positron scattering resonance whose density is found within the framework of the fullerene cluster.
Download or read book Non neutral Plasma Physics II written by Joel Fajans and published by American Institute of Physics. This book was released on 1995 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt: Annotation The study of non-neutral plasmas in traps is the keystone that connects parts of atomic and molecular physics, fluid dynamics, condensed matter physics, astrophysics, and antimatter physics with a variety of technologies such as atomic clocks, cyclotron mass spectrometers and a new standard for a pressure gauge, coherent radiation sources, accelerators, and fusion. Among the topics in 32 papers: long ion plasma confinement times with a "rotating wall"; pressure measurement using a pure electron plasma; and laser-cooled trapped-ion experiments at NIST. Includes an introduction by C.W. Roberson. No subject index. Annotation c. by Book News, Inc., Portland, Or.
Download or read book Proceedings of the Third International Workshop on Positron Electron Gas Scattering Wayne State University Detroit Michigan July 16 18 1985 written by Walter E. Kauppila and published by World Scientific Publishing Company Incorporated. This book was released on 1986 with total page 353 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Positron Annihilation written by Zsolt Kajcsos and published by . This book was released on 1992 with total page 732 pages. Available in PDF, EPUB and Kindle. Book excerpt: The volumes present over 400 reviewed papers on the present state of the art and future prospects in the wide field of research involving positrons. The foreword by Edward Teller and the summaries by Jean-Charles Abbe (Chemistry) and Alfred Seeger (Physics) demonstrate how the field is seen from outside and from inside.
Download or read book Physics Briefs written by and published by . This book was released on 1994 with total page 934 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Energy resolved Positron molecule Annihilation written by Levi Daniel Barnes and published by . This book was released on 2005 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effect of Asymmetries on Nonneutral Plasmas written by John Anthony Notte and published by . This book was released on 1993 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1977 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1975 with total page 1146 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book New Directions in Antimatter Chemistry and Physics written by Clifford M. Surko and published by Springer Science & Business Media. This book was released on 2007-05-08 with total page 509 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume is the outgrowth of a workshop held in October, 2000 at the Institute for Theoretical Atomic and Molecular Physics at the Harvard- Smithsonian Center for Astrophysics in Cambridge, MA. The aim of this book (similar in theme to the workshop) is to present an overview of new directions in antimatter physics and chemistry research. The emphasis is on positron and positronium interactions both with themselves and with ordinary matter. The timeliness of this subject comes from several considerations. New concepts for intense positron sources and the development of positron accumulators and trap-based positron beams provide qualitatively new experimental capabilities. On the theoretical side, the ability to model complex systems and complex processes has increased dramatically in recent years, due in part to progress in computational physics. There are presently an intriguing variety of phenomena that await theoretical explanation. It is virtually assured that the new experimental capabilities in this area will lead to a rapid expansion of this list. This book is organized into four sections: The first section discusses potential new experimental capabilities and the uses and the progress that might be made with them. The second section discusses topics involving antihydrogen and many-body phenomena, including Bose condensation of positronium atoms and positron interactions with materials. The final two sections treat a range of topics involving positron and positronium interactions with atoms and molecules.
Download or read book Government Reports Annual Index written by and published by . This book was released on 1991 with total page 1656 pages. Available in PDF, EPUB and Kindle. Book excerpt:
