Possible interpretation of the rho' (1600) as a threshold enhancement

Journal Article · Sun Feb 01 04:00:00 EST 1976 · Phys. Rev., D, v. 13, no. 3, pp. 697-706

OSTI ID:4016747

Langacker, P; Segre, G

The possibilty that the rho' (1600) is not a true resonance is examined. In the model considered the reactions $gamma$p $Yields$ rho$pi$$sup +$$pi$$sup - $p and e$sup +$$e$$sup -$ $Yields$ rho$pi$$sup +$$pi$$sup -$ proceed through the production of a virtual rho meson. The threshold factors associated with the opening of the rho$pi$$pi$ channel are shown to combine with the virtual-rho propagators to produce peaks in the rho$pi$$sup +$$pi$$sup -$ mass spectra, similar in mass and width to the experimental spectra. However, a comparison of the relative magnitudes of the two reactions, when combined with experimental limits on the reaction $pi$$sup +$p $Yields$ $delta$$sup ++$rho$pi$$sup +$$pi$$sup -$, rules out this mechanism. The roles of final-state interactions and of the virtual mass dependence of the $gamma$p $Yields$ rhop production amplitude are considered. It is then assumed that the rho' is a real resonance. The rho'-$gamma$ coupling and the rho'p total cross section are extracted. f/sub rho//sub prime/ $sup 2$/4$pi$ = 21 +- 10 and sigma/sub rho//sub prime//subp = 23 +- 4 mb are found, as compared with the rho-meson values of 2.1 +- 0.5 and 22.2 +- 2.6 mb. The background due to a rho tail in the production of the recently reported rho' (1250) is briefly discussed. (AIP)

• Research Organization: Department of Physics, University of Pennsylvania, Philadelphia, Pennsylvania 19174
• NSA Number: NSA-33-031438
• OSTI ID: 4016747
• Journal Information: Phys. Rev., D, v. 13, no. 3, pp. 697-706, Journal Name: Phys. Rev., D, v. 13, no. 3, pp. 697-706; ISSN PRVDA
• Country of Publication: United States
• Language: English

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