Summary
In the study of the annihilation\(\bar pn \to \pi ^ + \pi ^ + \pi ^ - \pi ^ - \pi ^ - \) at rest in deuterium, we have found a deviation of the π+π+π-π- effective-mass distribution with respect to the prediction of phase space. We show that this deviation could be satisfactorily explained in terms of a ρρ resonance withm=1.410, γ=0.090 GeV/c2 J PG=0++ andI=0 or 2.
Riassunto
Nel corso di uno studio dell'annichilazione\(\bar pn \to \pi ^ + \pi ^ + \pi ^ - \pi ^ - \pi ^ - \) a riposo in deuterio si è rilevata una deviazione dal comportamento previsto dallo spazio delle fasi per la distribuzione della massa effettiva del sistema π+π+π-π-. Si dimostra che tale deviazione può essere spiegata in maniera soddisfacente in termini di una risonanza γγ conm-1.410 e γ=0.090 GeV/c2,J PG=0++ eI=0 o 2.
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V. E. Barnes, B. B. Culwick, P. Guidoni, G. R. Kalbfleisch, G. W. London, R. B. Palmer, D. Radojicić, D. C. Rahn, R. R. Rau, C. R. Richardson, N. P. Samios, J. R. Smith, B. Goz, N. Horwitz, T. Kikuchi, J. Leitner andR. Wolfe:Phys. Rev. Lett.,15, 322 (1965).
S. L. Glashow andR. H. Socolov:Phys. Rev. Lett.,15, 329 (1965);R. Gatto, L. Maiani andG. Preparata:Nuovo Cimento,39, 1192 (1965).
Centro Nazionale Analisi Fotogrammi dell'I.N.F.N., Bologna.
This curve is relatively insensitive to the angular momentum assumed for the ρρ pair (see below).
Briefly, the method consists in taking events at random in mementum space, weighing each event proportionally to the square of the matrix element of the hypothesis to be tested, and then dealing with it exactly in the same way as with a physical event in building up the desired distributions.
We neglect here the possible contribution of waves higher than the8-wave to the initial state. The3 S 1 state of\(\bar pn\) is forbidden to go into an odd number of pions byG-partiy. This leaves only the1 S 0 as a possible initial state.
C. Zemach:Phys. Rev.,133, B 1201 (1964).
G. B. Chadwick, W. T. Davies, M. Derrick, C. J. B. Hawkins, P. B. Jones, J. H. Mulvey, D. Radojicić, C. A. Wilkinson, M. Cresti, A. Grigoletto, S. Limentani, A. Loria, L. Peruzzo andR. Santangelo:Proceedings of the 1962CERN International Conference on High-Energy Physics, p. 73.
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Bettini, A., Cresti, M., Limentani, S. et al. Evidence for a strong, possibly resonant, scalar ρρ interaction. Nuovo Cimento A (1965-1970) 42, 695–702 (1966). https://doi.org/10.1007/BF02720545
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DOI: https://doi.org/10.1007/BF02720545