Polarisation Effect of ρ Produced in \( \bar pp \) Interactions at 5.7, 12 and 22.4 GeV/c
The ρ meson spin alignment is studied in \( \bar pp \) interactions at 22.4 GeV/c and in the reaction \( \bar pp \to 2\pi ^ + 2\pi ^ - \) + neutrals at 5.7 GeV/c. An essential ρO meson spin alignment is observed. The values of the ρT OO element of the meson spin density matrix in the transversity frame are equal to 0.56±0.07, 0.53±0.05 and 0.54±0.04 at the above mentioned interactions, respectively. The value ρT OO = 0.64±0.06 for ρ± from the channel \( \bar pp \to 2\pi ^ + 2\pi ^ - \pi ^0 \) at 5.7 GeV/c was obtained. An increase of ρT OO with transverse momentum is obtained.
KeywordsTransverse Momentum Spin Alignment Annihilation Channel Decay Angular Distribution Meson Spin
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- 1.See e.g. AIP Conf. Proc., No. 99 Part, and Fields, Subseries No. 28, New York, 1983: High Energy Spin Physics 1982.Google Scholar
- 4.B.V. Batyunya et al., Ludmila Collaboration to be published.Google Scholar
- J. Cvach, V. Simak, Czech. J. Phys. B30 (1980) 72.Google Scholar
- 8.V. Blobel et al., Phys. Lett. 48b (1974) 73; more detailed comparison of \( \bar pp \) and pp data, using the same method of analysis, will be published elsewhere.Google Scholar
- S. Nandi et al., Phys. Rev. D17 (1978) 1 336.Google Scholar
- 11.A.V. Efremov, O.V. Teryaev, Preprint JINR P2–82-832, Dubna, 1982.Google Scholar
- 13.V.V. Babintzev et al., Yad. Fiz. 39 (1984) 1189Google Scholar