Metastable states of antiprotonic helium in the energy range of the 2S and 2P states of helium: Hyperspherical analysis of the system

Metastable states of antiprotonic helium bar pHe+ whose energies lie in the range of the 2S and 2P excited states of He are discussed and their energies are calculated using the hyperspherical method within the open-quote open-quote symmetric top close-quote close-quote approximation. These states can be populated via collisions of antiprotons with excited He atoms. They represent another group of the potentially observable metastable states of bar pHe+, which are characterized by the total angular momentum L∼70, in contrast to the recently discovered metastable states having L∼35. copyright 1996 The American Physical Society