Abstract
We report results of an experiment to search for a resonance enhancement of the
e+e− scattering cross section in a metallic Li target utilizing an energy-tunable monoenergetic positron beam. Within statistical uncertainties (0.27%) no evidence has been observed for deviations from Bhabha scattering over the entire invariant-mass region 1560 keV/c2<M0X<1860 keV/c2 that can be associated with the e+e− sum-peak energies in GSI heavy-ion experiments. Under the assumptions that the e+e− channel dominates, we deduce lower limits on lifetimes τ>3.3×10−13 sec (J=0) and τ>8.2×10−13 sec (J=1), at 90% C.L.
e+e− scattering cross section in a metallic Li target utilizing an energy-tunable monoenergetic positron beam. Within statistical uncertainties (0.27%) no evidence has been observed for deviations from Bhabha scattering over the entire invariant-mass region 1560 keV/c2<M0X<1860 keV/c2 that can be associated with the e+e− sum-peak energies in GSI heavy-ion experiments. Under the assumptions that the e+e− channel dominates, we deduce lower limits on lifetimes τ>3.3×10−13 sec (J=0) and τ>8.2×10−13 sec (J=1), at 90% C.L.
Original language | English |
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Pages (from-to) | 1729-1732 |
Journal | Physical Review Letters |
Volume | 69 |
Issue number | 12 |
DOIs | |
Publication status | Published - 1992 |
MoE publication type | A1 Journal article-refereed |