Positronium-positronium interaction: Resonance, scattering length, and Bose-Einstein condensation
نویسنده
چکیده
The low-energy scattering of ortho positronium (Ps) by ortho Ps has been studied in a full quantum mechanical coupled-channel approach. In the singlet channel (total spin sT = 0) we find Sand P-wave resonances at 3.35 eV (width 0.02 eV) and 5.05 eV (width 0.04 eV), respectively and a binding of 0.43 eV of Ps2. The scattering length for sT = 0 is 3.95 Å and for sT = 2 is 0.83 Å. The small sT = 2 scattering length makes the spin-polarized ortho Ps atoms an almost noninteracting ideal gas which may undergo Bose-Einstein condensation. Pacs Numbers: 34.85.+x, 03.75.Fi, 82.30.Gg
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تاریخ انتشار 2008