Summary
We have observed angular correlation effects between pions emitted from antiproton annihilation events. This experiment was carried out with a separated antiproton beam of momentum p anti-p = 1.05 BeV/c. A total of 2500 annihilation events were observed in 20000 pictures taken with the Lawrence Radiation Laboratory 30-in. propane bubble chamber. Pion pairs formed by the charged pions emitted in an antiproton-annihilation event can be considered in two groups: viz., like pairs
(in the isotopic-spin state I = 2) and unlike pairs (in the isotopic-spin states I = 0, 1, or 2). We searched for correlation effects in these separate groups. Our results show that the distribution of the angles between pions of like charges is strikingly different from the distribution of the angles between pions of unlike charges. (Extracted from the introductory part of the paper.).
Accelerator
LBL
Detectors HLBC-30IN
Related references See also L. W. Alvarez et al., Phys. Rev. Lett. 2 (1959) 215;
W. R. Frazer and J. R. Fulco, Phys. Rev. Lett. 2 (1959) 365;
O. Chamberlain et al., Phys. Rev. 113 (1959) 1615;
P. P. Strivastava and E. C. G. Sudarshan, Phys. Rev. 110 (1958) 765;
Reactions
anti-p p 2π+ 2π
1.05 GeV (Plab)
cor, ang
anti-p p 3π+ 3π
1.05 GeV (Plab)
cor, ang
Record comments
First observation of an enhancement in the production of like-charge pairs of pions with similar momenta.