Positron impact ionization of krypton and xenon

2000 ◽  
Vol 77 (10) ◽  
pp. 769-774 ◽  
Author(s):  
R I Campeanu ◽  
R P McEachran ◽  
A D Stauffer
Keyword(s):  
Energy Range ◽  
Cross Sections ◽  
Free Electron ◽  
Impact Ionization ◽  
Plane Waves ◽  
Distorted Wave ◽  
Positron Impact ◽  
Full Energy ◽  
Alternate Model ◽  
Wave Models

Several distorted-wave models for positron ionization of krypton and xenon are investigated. Our previous CPE (Coulomb plus Plane waves -- full Energy range) model produces reliable cross sections for krypton. For xenon, at high positron energies, the CPE results fall below experiment. We have proposed an alternate model DCPE4 that works well for both krypton and xenon. A common feature of both of these models is that the free electron and positron are treated differently.PACS No.: 34.90.+q

Near-threshold ionization of atoms and molecules by positron impact

2003 ◽  
Vol 81 (7) ◽  
pp. 919-927 ◽  
Author(s):  
R I Campeanu ◽  
L Nagy ◽  
A D Stauffer
Keyword(s):  
Power Law ◽  
Cross Sections ◽  
Experimental Results ◽  
Threshold Power ◽  
Distorted Wave ◽  
Positron Impact ◽  
Atoms And Molecules ◽  
Wave Models ◽  
Impact Energies ◽  
34.50 Fa

Distorted-wave models previously used to study the ionization of hydrogen and the noble gases by positron impact at medium kinetic energies are employed to produce cross sections for impact energies within 0.02 eV of the ionization threshold. These theoretical cross sections are compared with the Wannier–Klar threshold power-law formula and the existing experimental results. PACS Nos.: 34.50.Fa, 34.85.+x

Positron-impact ionization of atomic hydrogen in the distorted-wave polarized-orbital method

1990 ◽  
Vol 68 (2) ◽  
pp. 249-252 ◽  
Author(s):  
K. K. Mukherjee ◽  
Keka Basu Choudhury ◽  
N. Ranjit Singh ◽  
P. S. Mazumdar ◽  
S. Brajamani
Keyword(s):  
Cross Sections ◽  
Atomic Hydrogen ◽  
Impact Ionization ◽  
Theoretical Calculations ◽  
Orbital Method ◽  
Distorted Wave ◽  
Positron Impact ◽  
Positron Energy ◽  
The Matrix ◽  
Final Channel

Calculations are performed for the total cross sections for the positron-impact ionization of the ground state of atomic hydrogen, employing the distorted wave polarized orbital method. This explicitly takes into account the matrix elements arising from the distorted part of the target wave function and the effect of final-channel distortion in the incident-positron energy range 20.4–68 eV. The results are compared with available theoretical calculations.

scholarly journals Few Body Effects in the Electron and Positron Impact Ionization of Atoms

Atoms ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 33
Author(s):  
R.I. Campeanu ◽  
Colm T. Whelan
Keyword(s):  
Electron Impact ◽  
Cross Sections ◽  
Differential Cross ◽  
Impact Ionization ◽  
Inert Gas ◽  
Interference Effects ◽  
Positron Impact ◽  
Competing Interactions ◽  
Energy Sharing

Triple differential cross sections (TDCS) are presented for the electron and positron impact ionization of inert gas atoms in a range of energy sharing geometries where a number of significant few body effects compete to define the shape of the TDCS. Using both positrons and electrons as projectiles has opened up the possibility of performing complementary studies which could effectively isolate competing interactions that cannot be separately detected in an experiment with a single projectile. Results will be presented in kinematics where the electron impact ionization appears to be well understood and using the same kinematics positron cross sections will be presented. The kinematics are then varied in order to focus on the role of distortion, post collision interaction (pci), and interference effects.

Positron-impact ionization of helium in the distorted-wave polarized-orbital method

1989 ◽  
Vol 39 (4) ◽  
pp. 1756-1759 ◽  
Author(s):  
K. K. Mukherjee ◽  
P. S. Mazumdar ◽  
S. Brajamani
Keyword(s):  
Impact Ionization ◽  
Orbital Method ◽  
Distorted Wave ◽  
Positron Impact

scholarly journals Ground State Positronium Formation Cross Sections for Scattering of Positrons from Li

1991 ◽  
Vol 44 (5) ◽  
pp. 515 ◽  
Author(s):  
KK Mukherjee ◽  
N Ranjit Singh ◽  
Keka Basu Choudhury ◽  
PS Mazumdar ◽  
S Brajamani
Keyword(s):  
Energy Range ◽  
Cross Sections ◽  
Ground State ◽  
Positronium Formation ◽  
Distorted Wave ◽  
Total Cross Sections ◽  
Wave Approximation ◽  
Theoretical Predictions

Total cross sections for positronium formation in e+-Li scattering have been studied in the framework of the distorted wave approximation in the energy range 1-50 eV by taking consistent account of the effect of the target distortion. The results are compared with existing theoretical predictions.

Sign in / Sign up

Export Citation Format

Share Document