Results 251 to 260 of about 1,131,290 (276)

Modeling Multicusp Negative-Ion Sources

IEEE Transactions on Plasma Science, 2007
The study of negative-ion production and its optimization is of fundamental importance in the thermonuclear research field. Indeed, negative-ion beams are favorites for the generation of neutral particle beams used in fusion plasma heating because of their higher neutralization efficiency with respect to positive ions.
D Pagano, C Gorse, M Capitelli
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Photodetachment of negative halogen ions

Physical Review A, 1987
Results of relativistic random-phase approximation calculations of photodetachment cross sections and angular-distribution asymmetry parameters are presented for the outer shells of the negative ions ${\mathrm{F}}^{\mathrm{\ensuremath{-}}}$, ${\mathrm{Cl}}^{\mathrm{\ensuremath{-}}}$, ${\mathrm{Br}}^{\mathrm{\ensuremath{-}}}$, and ${\mathrm{I}}^{\mathrm{
, Radojevic, , Kelly, , Johnson
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Excited Negative Ions and Molecules and Negative Ion Production

1992
Abstract : Research has been performed to determine fundamental properties of negative ions; decay mechanisms and products of molecular Rydberg states; and mechanisms affecting H- production in ion source discharges. Experiments were performed on both stable and metastable states of Ca-, Cs-, He 2-, and WO3-; on the dissociative decay of Rydberg states
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Gas-phase solvated negative ions

Mass Spectrometry Reviews, 1998
The association of negative ions to neutral molecules has been an active field of research in gas-phase ion chemistry since 1970. For anions, which correspond to the conjugate base of well-known acids in solution, these species are often referred to as gas-phase solvated anions.
Keiko Takashima, José M. Riveros
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Regularities of Negative Ion Resonances

Topical Meeting on Multiple Excitations of Atoms, 1986
The effects of electron correlation in atomic and molecular systems are perhaps most pronounced in negative ions. No long-range Coulomb field is present to bind an additional electron to a parent state of a neutral atom. The stability of a negative ion state is thus usually attributed to one of two alternative mechanisms, both of which invoke electron ...
Charles W. Clark, Stephen J. Buckman
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Negative-Ion States

1985
Negative ions play important roles in many areas of photophysics and photochemistry. Negative ions can be produced directly by photodissociation of molecules through ion-pair production, or indirectly via charge exchange between photoexcited species and electronegative atoms or molecules.
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Atomic negative ions

AIP Conference Proceedings, 1992
We review some of the recent progress in the studies of alkaline‐earth, negative ions. Computations of autodetachment rates, electron affinities and transition wavelengths are discussed and some new and improved results are given.
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Photodetachment of Positronium Negative Ions

Physical Review Letters, 2011
Photodetachment of the positronium negative ion, a bound state of one positron and two electrons, has been observed. Development of a method to produce the ions efficiently using a Na coated tungsten surface has enabled the first observation of the photodetachment. The obtained lower limit of the photodetachment cross section for the wavelength of 1064
K, Michishio, T, Tachibana, H, Terabe, A, Igarashi, K, Wada, T, Kuga, A, Yagishita, T, Hyodo, Y, Nagashima   +8 more
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Negative Ion Mass Spectrometry, Methods*

1999
Negative ions can be formed by many ion sources, and although less predominant than their cationic counterparts, they can be observed and studied to provide complementary molecular and ionic structure and mechanistic information. This chapter discusses the production and use of negative ions for such purposes.
Suresh Dua, John H. Bowie
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Production of Negative Ions and Noise in Negative Ion Beams

Physical Review, 1953
In a search for high current sources of low energy (\ensuremath{\approx}100 ev) negative atomic ions of hydrogen and oxygen, five types of sources were examined. The most promising practical source for both ${\mathrm{H}}^{\ensuremath{-}}$ and ${\mathrm{O}}^{\ensuremath{-}}$ was found to be the dc glow discharge from which beams of ${10}^{\ensuremath ...
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