Molecular effects on antiproton capture by H{sub 2} and the states of {bar p}p formed
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
Complete five-body dynamical calculations of antiproton ({bar p}) capture by the hydrogen molecule (H{sub 2}) have been carried out using a generalization of the Kirschbaum-Wilets method (belonging to a class of quasiclassical methods sometimes called fermion molecular dynamics). The differences between capture by H{sub 2} and the H atom are found to be dramatic. The effects due to the two-center structure, rotational motions, and vibrational motions are distinguished. Of particular importance, the vibrational degree of freedom enables the molecule to capture antiprotons having lab energies above 100 eV, whereas atomic capture cuts off sharply above the ionization threshold of 27 eV (in the lab system). Antiproton capture by the atom is calculated by the same method as well as by the classical-trajectory Monte Carlo method, which is applicable only to the atom. The initial quantum numbers (assigned quasiclassically) of the {bar p}p formed are found to be shifted to significantly smaller values for the molecular target; the n distribution is also narrower for the molecular target as compared with the atomic target. {copyright} {ital 1997} {ital The American Physical Society}
- OSTI ID:
- 553974
- Journal Information:
- Physical Review A, Vol. 56, Issue 5; Other Information: PBD: Nov 1997
- Country of Publication:
- United States
- Language:
- English
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