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Title: Long-lived states of antiprotonic lithium pLi {sup +} produced in p+ Li collisions

Abstract

Antiproton capture by lithium atoms (p+Li{yields}pLi{sup +}+e) is investigated at collision energies from 0.01 to 10 eV by using a semiclassical (also know as quantum-classical hybrid) method, in which the radial distance between the antiproton and the Li{sup +} ion is treated as a classical variable, and the other degrees of freedom are described by quantum mechanics. Analyzing the wave packet of the emitted electrons and making use of the energy conservation rule enable us to calculate the state distribution of the produced antiprotonic lithium pLi{sup +} atoms and also to distinguish between the capture and ionization ({yields}p+Li{sup +}+e) channels at collisional energies above the ionization threshold. This method is tested for the capture of negative muons by hydrogen atoms, which was rigorously investigated in previous quantum mechanical studies. Most of the pLi{sup +} atoms produced in p+Li are found to be sufficiently stable against Auger decays and are experimentally observable as long-lived states. The present system bears close similarities to the system of p+He(2S). It is therefore expected that long-lived antiprotonic helium pHe{sup +} atoms can be efficiently produced in the p capture by metastable He(2 {sup 3}S) atoms.

Authors:
 [1]
  1. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Yoshinodai 3-1-1, Chuo-ku, Sagamihara, Kanagawa 252-5210 (Japan)
Publication Date:
OSTI Identifier:
22068686
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 84; Journal Issue: 3; Other Information: (c) 2011 American Institute of Physics; Country of input: Syrian Arab Republic
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; ANTIPROTONS; CAPTURE; COLLISIONS; DECAY; DEGREES OF FREEDOM; DISTRIBUTION; ELECTRONS; ENERGY CONSERVATION; EV RANGE; HELIUM; HELIUM 2; HYBRIDIZATION; HYDROGEN; IONIZATION; LITHIUM; LITHIUM IONS; MUONS; QUANTUM MECHANICS; SEMICLASSICAL APPROXIMATION; WAVE PACKETS

Citation Formats

Sakimoto, Kazuhiro. Long-lived states of antiprotonic lithium pLi {sup +} produced in p+ Li collisions. United States: N. p., 2011. Web. doi:10.1103/PHYSREVA.84.032501.
Sakimoto, Kazuhiro. Long-lived states of antiprotonic lithium pLi {sup +} produced in p+ Li collisions. United States. doi:10.1103/PHYSREVA.84.032501.
Sakimoto, Kazuhiro. 2011. "Long-lived states of antiprotonic lithium pLi {sup +} produced in p+ Li collisions". United States. doi:10.1103/PHYSREVA.84.032501.
@article{osti_22068686,
title = {Long-lived states of antiprotonic lithium pLi {sup +} produced in p+ Li collisions},
author = {Sakimoto, Kazuhiro},
abstractNote = {Antiproton capture by lithium atoms (p+Li{yields}pLi{sup +}+e) is investigated at collision energies from 0.01 to 10 eV by using a semiclassical (also know as quantum-classical hybrid) method, in which the radial distance between the antiproton and the Li{sup +} ion is treated as a classical variable, and the other degrees of freedom are described by quantum mechanics. Analyzing the wave packet of the emitted electrons and making use of the energy conservation rule enable us to calculate the state distribution of the produced antiprotonic lithium pLi{sup +} atoms and also to distinguish between the capture and ionization ({yields}p+Li{sup +}+e) channels at collisional energies above the ionization threshold. This method is tested for the capture of negative muons by hydrogen atoms, which was rigorously investigated in previous quantum mechanical studies. Most of the pLi{sup +} atoms produced in p+Li are found to be sufficiently stable against Auger decays and are experimentally observable as long-lived states. The present system bears close similarities to the system of p+He(2S). It is therefore expected that long-lived antiprotonic helium pHe{sup +} atoms can be efficiently produced in the p capture by metastable He(2 {sup 3}S) atoms.},
doi = {10.1103/PHYSREVA.84.032501},
journal = {Physical Review. A},
number = 3,
volume = 84,
place = {United States},
year = 2011,
month = 9
}
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