scholarly journals Positronium-Proton Scattering at Low Energies

1995 ◽  
Vol 48 (6) ◽  
pp. 893 ◽  
Author(s):  
Jim Mitroy
Keyword(s):  
Electron Transfer ◽  
Cross Sections ◽  
Low Energy ◽  
Proton Scattering ◽  
Close Coupling ◽  
Low Energies ◽  
Coupling Approach ◽  
Channel Space ◽  
Three Body

Calculations of low energy positronium-proton scattering using the close coupling approach are reported at energies below the three-body breakup energy of 0�5 Rydberg. The channel space includes nine physical hydrogen and positronium states and in addition twelve hydrogen and positronium pseudo-states. Total elastic and electron-transfer cross sections are reported at incident energies below the ionisation threshold. Cross sections for electron transfer to the H(n=2) and H(n=3) levels are also reported.

scholarly journals Large Basis Calculation of Positron?Hydrogen Scattering at Low Energies

1995 ◽  
Vol 48 (4) ◽  
pp. 645 ◽  
Author(s):  
Jim Mitroy
Keyword(s):  
Cross Sections ◽  
Reaction Cross ◽  
Positronium Formation ◽  
Total Reaction Cross Section ◽  
Close Coupling ◽  
Variational Calculations ◽  
Low Energies ◽  
Coupling Approach ◽  
Channel Space ◽  
Basis Calculation

Calculations of low energy positron-hydrogen scattering using the close coupling approach are reported at low energies. The channel space includes nine physical hydrogen and positronium states and in addition twelve hydrogen and positronium pseudo-states. For energies below the positronium formation threshold, phase shifts are reported for J = 0 to 6 and are believed to have an absolute accuracy of 0�0015 radian or better. Elastic scattering and positronium formation cross sections in the Ore gap for the J = 0 and J = 1 partial waves are essentially identical with previous variational calculations. Total elastic and positronium formation cross sections are reported at incident energies below the ionisation threshold. Cross sections for the excitation of the H(n=2), H(n=3) and Ps( n=2) levels are also reported over a restricted energy range, and the total reaction cross section has been computed and compared with experiment.

Inelastic collisions at low energies

1969 ◽  
Vol 47 (10) ◽  
pp. 1723-1729 ◽  
Author(s):  
A. Dalgarno
Keyword(s):  
Energy Loss ◽  
Cross Sections ◽  
Low Energy ◽  
Inelastic Collisions ◽  
Low Energies ◽  
Low Energy Electrons ◽  
The Cross ◽  
Loss Rates

A summary is presented of the processes by which low energy electrons lose energy in moving through the atmosphere and estimates are given of the cross sections and energy loss rates. The mechanisms by which thermal electrons cool are described and the cooling efficiencies are listed.

scholarly journals Three-body systems in physics of cold atoms and halo nuclei

2016 ◽  
Vol 25 (05) ◽  
pp. 1641003 ◽  
Author(s):  
Chen Ji
Keyword(s):  
Field Theory ◽  
Effective Field Theory ◽  
Cold Atoms ◽  
Effective Field ◽  
Low Energy ◽  
Halo Nuclei ◽  
Particle Interactions ◽  
Body Contact ◽  
Low Energies ◽  
Three Body

Few-body systems, such as cold atoms and halo nuclei, share universal features at low energies, which are insensitive to the underlying inter-particle interactions at short ranges. These low-energy properties can be investigated in the framework of effective field theory with two-body and three-body contact interactions. I review the effective-field-theory studies of universal physics in three-body systems, focusing on the application in cold atoms and halo nuclei.

scholarly journals CALCULATION OF THE ELASTIC p6He AND p8He SCATTERING IN GLAUBER APPROXIMATION

2013 ◽  
Vol 22 (04) ◽  
pp. 1350017 ◽  
Author(s):  
ELENA IBRAEVA ◽  
ONLASYN IMAMBEKOV ◽  
ALBERT DZHAZAIROV-KAHRAMANOV
Keyword(s):  
Cross Sections ◽  
Optical Model ◽  
High Energy ◽  
Proton Scattering ◽  
Diffraction Scattering ◽  
Multiple Diffraction ◽  
Weakly Bound ◽  
Analyzing Powers ◽  
Elastic Proton ◽  
Three Body

A series of calculations of differential cross-sections (DCSs) and analyzing powers (Ay) of the elastic proton scattering on isotopes 6 He and 8 He were presented in the framework of the theory of Glauber multiple diffraction scattering. The three-body α–n–n and harmonic oscillator wave functions (WFs) were used for 6 He , for 8 He — the function of density distribution in LSSM. For p6 He scattering, the expansion of the Glauber operator into a series of multiple-scattering is written in the form consistent with the picture of weakly bound clusters in halo-nuclei, while for p8 He scattering the members of single and double collisions are included in the operator. We have done the comparison of our results with available experimental data (including new data of Ay for p6 He scattering at the E = 71 MeV/nucleon) and with the calculations' results in the other approaches (high-energy, optical model, RMF). Also, a comparison of the characteristics of two isotopes 6 He and 8 He was made, which showed that they correlate quite well with each other.

scholarly journals Asymptotic theory of charged particle transfer reactions at low energies and nuclear astrophysics

2019 ◽  
Vol 49 ◽  
pp. 1960016
Author(s):  
R. Yarmukhamedov ◽  
K. I. Tursunmakhatov ◽  
N. Burtebayev
Keyword(s):  
Cross Sections ◽  
Asymptotic Theory ◽  
Nuclear Astrophysics ◽  
Transfer Reactions ◽  
Dispersion Theory ◽  
Low Energies ◽  
Proton Transfer Reactions ◽  
Stellar Energy ◽  
Text Model ◽  
Three Body

An asymptotic theory is proposed for the peripheral transfer [Formula: see text] reaction at low energies within the three-body ([Formula: see text], [Formula: see text] and [Formula: see text]) model by combining the dispersion theory and DWBA, where [Formula: see text], [Formula: see text] and [Formula: see text] is a transferred particle. The contribution of the three-body ([Formula: see text], [Formula: see text] and [Formula: see text]) Coulomb dynamics of the transfer mechanism both to the peripheral partial amplitudes for the partial wave [Formula: see text] and to the DWBA amplitude is investigated. The results of the analysis of the differential cross sections of the specific proton transfer reactions at above-barrier energies are presented. New estimates and their uncertainties are obtained for values of the asymptotic normalization coefficients for [Formula: see text] and [Formula: see text] as well as for the direct astrophysical [Formula: see text] factors at stellar energy of the radiative capture [Formula: see text] and [Formula: see text] reactions.

Hyperspherical close-coupling calculations for charge-transfer cross sections inHe2++H(1s)collisions at low energies

2003 ◽  
Vol 67 (5) ◽  
Author(s):  
Chien-Nan Liu ◽  
Anh-Thu Le ◽  
Toru Morishita ◽  
B. D. Esry ◽  
C. D. Lin
Keyword(s):  
Charge Transfer ◽  
Cross Sections ◽  
Close Coupling ◽  
Low Energies

scholarly journals Antiproton-nucleus annihilation cross section at low energy

2018 ◽  
Vol 182 ◽  
pp. 03013
Author(s):  
H. Aghai–Khozani ◽  
A. Bianconi ◽  
M. Corradini ◽  
R. Hayano ◽  
M. Hori ◽  
...  
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Medical Physics ◽  
Low Energy ◽  
Annihilation Cross Section ◽  
Experimental Result ◽  
Heavy Nuclei ◽  
Fundamental Physics ◽  
Low Energies ◽  
Few Data

The antinucleon-nuclei annihilation cross sections at low energies were systematically measured at CERN in the 80’s and 90’s with the LEAR facility and later with the Antiproton Decelerator. Unfortunately only few data exist for very low energy antiprotons (p<500 MeV/c) on medium and heavy nuclei. A deeper knowledge is required by fundamental physics and can have consequence also in cosmology and medical physics. In order to fill the gap, the ASACUSA Collaboration has very recently measured the annihilation cross section of 100 MeV/c antiprotons on carbon. In the present work the experimental result is presented together with a comparison both with the antineutron data on the same target at the same energies and with the other existing antiproton data at higher energies.

The rotational excitation of carbon monoxide by hydrogen atom impact

1975 ◽  
Vol 342 (1629) ◽  
pp. 191-207 ◽  
Keyword(s):  
Carbon Monoxide ◽  
Cross Sections ◽  
Rate Coefficients ◽  
Rotational Degree ◽  
Rotational Excitation ◽  
Body Frame ◽  
Hydrogen Atoms ◽  
Close Coupling ◽  
Coupling Methods ◽  
Low Energies

A quantal study is carried out of the rotational excitation of carbon monoxide in collision with hydrogen atoms. The interaction potential at short range is constructed semi-empirically and joined to the Buckingham potential at long range. The close-coupling formulation is used to assess the reliability of the fixed-nuclei approximation, which is developed in terms of the adiabatic theory of electron-molecule scattering. The applicability of two simplified close-coupling formulations, introduced by Rabitz and by McGuire & Kouri, is examined. We found that the fixed nuclei method is unpromising at low energies and time-consuming at high energies. The two simplified close-coupling methods are capable of providing results of useful accuracy. The similarity in formulation of the fixed-nuclei and one of the close-coupling methods, both of which are body-frame treatments, and the differences in their results show that the rotational degree of freedom must be treated rigorously. The method of Rabitz is economical, and we adopted it to calculate the energy dependent rotation excitation cross sections for the scattering of H + CO. The results are presented in the form of Maxwellian-averaged rate coefficients in the temperature range of 5-150 K.

Sign in / Sign up

Export Citation Format

Share Document