Double diffractive ρ−production in γ∗γ∗ collisions
نویسندگان
چکیده
We present a first estimate of the cross-section for the exclusive process γ L(Q 2 1)γ ∗ L(Q 2 2) → ρLρL, which will be studied in the future high energy e+e−− linear collider. As a first step, we calculate the Born order approximation of the amplitude for longitudinally polarized virtual photons and mesons, in the kinematical region s ≫ −t, Q1 , Q2. This process is completely calculable in the hard region Q1 , Q 2 2 ≫ ΛQCD. We perform most of the steps in an analytical way. The resulting cross-section turns out to be large enough for this process to be measurable with foreseen luminosity and energy, for Q1 and Q 2 2 in the range of a few GeV. Unité mixte C7644 du CNRS Unité mixte 8627 du CNRS
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