1. Rare pion double radiative capture reactions on hydrogen and deuterium.
- Author
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Hasinoff, M. D., Armstrong, D. S., Clark, J., Gorringe, T. P., Kovash, M., Tripathi, S., Wright, D. H., and Z.ol\nierczuk, P. A.
- Subjects
- *
PIONS , *HYDROGEN , *DEUTERIUM ,CAPTURE - Abstract
Abstract. The rare 2-photon radiative capture reaction has been observed for the first time on hydrogen and deuterium using the RMC high acceptance cylindrical pair spectrometer at TRIUMF. Our preliminary branching ratios are 3.8 x 10[sup -5] for hydrogen and 1.6x10[sup -5] for deuterium. Our π[sup -]p data confirms the predicted dominance of the ππ → γγ annihilation mechanism. Moreover, since crossing symmetry relates ππ → γγ to γπ → γπ this threshold (π, 2γ) reaction might also provide new information on the electric polarizability of the pion. Our π[sup -]d data shows no evidence for the predicted d[sup *][sub 1] (1920) dibaryon. [ABSTRACT FROM AUTHOR]
- Published
- 2000