Exotic States X[sup ±](1600,I[sup G](J[sup PC]) = 2[sup +](2[sup + +])) in Photoproduction Reactions.

It is shown that the list of unusual mesons that are planned to be studied in photoproduction reactions can be supplemented with I[sup G] (J[sup PC]) = 2[sup +] (2[sup ++]) exotic states X[sup ±](1600), which are natural to seek as manifestations of the ρ[sub ±]ρ[sup 0] decay channels in the reactions γN → ρ[sub ±]ρ[sup 0]N and γN → ρ[sub ±]ρ[sup 0]&Delta A classification of the ρ[sub ±]ρ[sup 0] states according to their quantum numbers is presented. A model for the spin structure of the amplitudes for the reactions γp → ƒ[sub 2](1270)p, γp → a[sub 2][sup 0] (1320)p, and γN → X[sub ±](N, Δ) is proposed, and estimates are obtained for the corresponding cross sections. At E[sub γ] ≈ 6 GeV, it is found that σ(γp → ƒ[sub 2](1270)p) ≈ 0.12 µb, A σ(γp → a[sub 2][sup 0] (1320)p) ≈ 0.25 µb, σ(γN → X[sup ±]N → ρ[sub ±]ρ[sup 0]N) &≈ 0.018 µb, and σ (γp → X[sup -] Δ[sup ++] → ρ[sup -]ρ[sup 0] Δ[sup ++]) ≈ 0.031 µb. The problem of isolating signals from X[sup ±] states against the natural background that is associated with other channels of π[sup ±]π[sup 0]π[sup +]π[sup -] production is discussed. It is deduced that searches for exotic states X[sup ±](2[sup +] (2[sup ++])) in experiments at JLAB will be quite efficient—for example, the yield of about 2.8 x 10[sup 6] events per month is expected to correspond to the estimated cross sections for the reactions γN → X[sup ±]N → ρ[sub ±]ρ[sup 0]N. [ABSTRACT FROM AUTHOR]