Electron transfer measurements from rare gas targets to O12+ ions between 60 and 200 keV

1980 ◽  
Vol 58 (6) ◽  
pp. 772-778 ◽  
Author(s):  
B. Hird ◽  
S. P. Ali
Keyword(s):  
Cross Sections ◽  
Spin Symmetry ◽  
Rare Gas ◽  
Final States ◽  
Rare Gases ◽  
Product Ions ◽  
The Cross ◽  
Gas Targets ◽  
Crossing Theory ◽  
Relative Weighting

Charge exchange measurements in thin targets of the rare gases by an O2+ beam have been made between 60 and 200 keV. Taking into account the relative weighting of the final states which are allowed assuming spin, symmetry, and Λ conservation it was found that a crossing theory of the Landau–Zener type is completely inadequate to account for the cross sections of the heavier targets, whereas a non-crossing theory in the Rapp–Francis formulation was found to give good fits, both in energy dependence and overall magnitude, to the cross sections except for the xenon target where it is too small by a factor of 2. The improvement in fit is due to the inclusion of a factor which was omitted in the original formulation of Rapp–Francis, and also the inclusion of many states of the product ions in the calculation.

Electron capture and loss by fast fluorine atoms in collisions with rare gas targets

1988 ◽  
Vol 66 (11) ◽  
pp. 972-977 ◽  
Author(s):  
B. Hird ◽  
F. Rahman ◽  
M. W. Orakzai
Keyword(s):  
Cross Sections ◽  
Rare Gas ◽  
Rare Gases ◽  
Single Atoms ◽  
Positive Ions ◽  
Electron Transfer Theory ◽  
The Cross ◽  
Fluorine Ions ◽  
Gas Targets ◽  
Pass Through

Cross sections are reported for the production of fast negative fluorine ions in collisions between a neutral fluorine beam and single atoms of each of the rare gases, at collision energies between 20 and 110 keV. The energies at which the cross sections pass through a maximum fit very well with the Massey criterion, assuming a simple electron-transfer theory. The cross sections for the production of fast fluorine positive ions are also reported. These are found to be smallest for the heavy targets and reach a maximum in helium and neon, which have higher ionization potentials than fluorine.

Stueckelberg-Landau-Zener-(SLZ)-Modell für atomare Stoßprozesse / Stueckelberg-Landau-Zener-(SLZ) Model for Atomic Scattering Processes

1973 ◽  
Vol 28 (10) ◽  
pp. 1642-1653
Author(s):  
G.-P. Raabe
Keyword(s):  
Cross Sections ◽  
Differential Cross ◽  
Wave Functions ◽  
Differential Cross Sections ◽  
Rare Gases ◽  
Radial Wave ◽  
Atomic Scattering ◽  
The Cross

Scattering processes of atoms, molecules and ions with two crossing electronic potentials may be treated in the Stueckelberg-Landau-Zener-(SLZ) model. In this paper the WKB-solutions for the radial wave functions, given by Stueckelberg are used to calculate differential cross sections. The effects on the cross sections are explained in a semiclassical picture, following the procedures of Ford and Wheeler, and Berry. In the scattering of H+ by rare gases, some effects in the elastic cross sections are observed which can be explained by the influence of the potential of the chargeexchanged particles, using the SLZ-model. The structure in the elastic cross sections for H2+-Kr can be explained as a rainbow structure with superimposed Stueckelberg oscillations.

Collisional electron detachment and decomposition cross sections for SF−6, SF−5, and F− on SF6 and rare gas targets

1989 ◽  
Vol 91 (4) ◽  
pp. 2254-2260 ◽  
Author(s):  
Yicheng Wang ◽  
R. L. Champion ◽  
L. D. Doverspike ◽  
J. K. Olthoff ◽  
R. J. Van Brunt
Keyword(s):  
Cross Sections ◽  
Rare Gas ◽  
Electron Detachment ◽  
Gas Targets

Electron loss cross sections from rare gas atoms to Ar+

1982 ◽  
Vol 60 (7) ◽  
pp. 977-980
Author(s):  
B. Hird ◽  
S. P. Ali
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Energy Region ◽  
Rare Gas ◽  
Electron Loss ◽  
Rare Gases ◽  
Thin Target ◽  
Rare Gas Atoms ◽  
Good Agreement

Measurements of the σ10 cross section for a beam of Ar+ ions of energies between 30 and 120 keV passing through a thin target of the rare gases show good agreement with the few previous measurements in this energy region.

scholarly journals LIGHT SUPERPARTNERS AT HADRON COLLIDERS

2006 ◽  
Vol 21 (26) ◽  
pp. 5221-5239 ◽  
Author(s):  
D. YU. BOGACHEV ◽  
A. V. GLADYSHEV ◽  
D. I. KAZAKOV ◽  
A. S. NECHAEV
Keyword(s):  
Parameter Space ◽  
Cross Sections ◽  
Gamma Ray ◽  
Light Neutralino ◽  
Final States ◽  
Hadron Colliders ◽  
Missing Energy ◽  
Breaking Mechanism ◽  
The Cross ◽  
Weakly Interacting Particles

Uncertainties of the MSSM predictions are due to an unknown SUSY breaking mechanism. To reduce these uncertainties, one usually imposes constraints on the MSSM parameter space. Recently, two new constraints became available, both from astrophysics: WMAP precise measurement of the amount of the Dark Matter in the Universe and EGRET data on an excess in diffuse gamma ray flux. Being interpreted as a manifestation of supersymmetry these data lead to severe constraints on parameter space and single out a very restricted area. The key feature of this area is the splitting of light gauginos from heavy squarks and sleptons. We study the phenomenological properties of this scenario, in particular, the cross-sections of superparticle production, their decay patterns and signatures for observation at hadron colliders, Tevatron and LHC. We found that weakly interacting particles in this area are very light so that the cross-sections may reach fractions of a pb with jets and/or leptons as final states accompanied by missing energy taken away by light neutralino with a mass around 100 GeV.

scholarly journals Test of QCD at large Q2 with exclusive hadronic processes

2014 ◽  
Vol 31 ◽  
pp. 1460304
Author(s):  
Chengping Shen ◽  
Keyword(s):  
Perturbative Qcd ◽  
Cross Sections ◽  
Branching Fractions ◽  
Center Of Mass ◽  
Axial Vector ◽  
Hadronic Decays ◽  
Final States ◽  
Final State ◽  
The Cross ◽  
Using Data

My report consists of two parts: (1). Using samples of 102 million ϒ(1S) and 158 million ϒ(2S) events at Belle, we study 17 exclusive hadronic decays of these two bottomonium resonances to some Vector-Pseudoscalar (VP), Vector-Tensor (VT) and Axial-vector-Pseudoscalar (AP) processes and their final states. Branching fractions are measured for all the processes. The ratios of the branching fractions of ϒ(2S) and ϒ(1S) decays into the same final state are used to test a perturbative QCD (pQCD) prediction for OZI-suppressed bottomonium decays. (2). Using data samples of 89 fb-1, 703 fb-1, and 121 fb-1 collected at center-of-mass (CMS) energies 10.52, 10.58, and 10.876 GeV, respectively, we measure the cross sections of e+e- → ωπ0, [Formula: see text], and [Formula: see text]. The energy dependence of the cross sections is presented.

Net ionisation cross sections of rare gas targets in collisions with swift highly charged ions

1993 ◽  
Vol 126 (1-4) ◽  
pp. 21-24 ◽  
Author(s):  
A. Cassimi ◽  
J. P. Grandin ◽  
L. H. Zhang ◽  
A. Gosselin ◽  
D. Hennecart ◽  
...  
Keyword(s):  
Cross Sections ◽  
Highly Charged Ions ◽  
Rare Gas ◽  
Gas Targets ◽  
Charged Ions

Single electron capture by N12+ in rare gas targets between 60 keV and 200 keV

1979 ◽  
Vol 57 (12) ◽  
pp. 2078-2083
Author(s):  
B. Hird ◽  
H. C. Suk ◽  
S. P. Ali
Keyword(s):  
Cross Section ◽  
Weighted Average ◽  
Rare Gas ◽  
Rare Gases ◽  
Single Electron Capture ◽  
Correct Energy ◽  
Type Calculation ◽  
Gas Targets ◽  
Singly Charged ◽  
Charged Ions

Charge exchange measurements in thin targets of the rare gases by a N2+ beam have been made between 60 keV and 200 keV. The singly charged ions produced in the collisions are expected to be produced in only a few allowed states, and a Rapp and Francis type calculation for the weighted average cross section to these allowed states was found to have generally the correct energy dependence but to be too small by a factor which increased from 4 in He to more than 10 in Xe. There was some evidence that the 4P state of N2+ may have been present in the beam in varying amounts.

Neutron Cross Sections for Some Threshold Reactions

1965 ◽  
Vol 20 (12) ◽  
pp. 1583-1587 ◽  
Author(s):  
Torbjörn Lagerwall
Keyword(s):  
Cross Sections ◽  
Fission Neutron ◽  
High Energy ◽  
Rare Gas ◽  
Coincidence Method ◽  
Rare Gases ◽  
Fission Neutron Spectrum ◽  
Neutron Reactions ◽  
Neutron Cross Sections ◽  
Gas Isotopes

Three neutron reactions leading to production of the rare gases Ar41 and Xe135 have been investigated. Single crystal samples of KF, CaF2, and BaF2 were irradiated in the Berlin reactor and the target-free absolute activities of the rare gas isotopes measured by a β-γ-coincidence method. The calculated cross sections areK41(n,p) Ar41: σ= ( 2,73±0,41) mb; σ0= (98,6±14,8) mb;Ca44 (n,a)Ar41: σ = (61,1 ±9,2) μb; σ0= (64,7± 9,7) mb;Ba138(n,a)Xe135: σ= ( 1,9 ±0,3) μb; σ0= ( 4,9± 0,7) mb.The first set of values are valid for a fission-neutron spectrum. The second set are calculated cross sections for the high energy plateau. They can be considered as valid for 15 MeV neutrons.

Resonance charge transfer between H(1s) and H + calculated by means of an approximation based on an expansion in atomic eigenfunctions

1961 ◽  
Vol 264 (1319) ◽  
pp. 547-557 ◽  
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Atomic Hydrogen ◽  
High Energy ◽  
Wave Functions ◽  
Final States ◽  
Energy Limit ◽  
Full Account ◽  
The Cross ◽  
Resonance Charge

An expression for the cross-section describing electron capture by protons in atomic hydrogen is derived from an expansion based on atomic wave functions. Full account is taken of momentum transfer and of the non-orthogonality of the wave functions of the initial and final states by the method due to Bates. The cross-sections have been computed for proton energies from 100 to 1 MeV. In the low energy limit, the results agree with the p.s.s. calculations of Dalgarno & Yadav and in the high energy limit with the calculations of Brinkm an & Kramers.

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