Engineering topics
Greco, M.
Publications and source records attributed to Greco, M..
Origin of the Q{sup 2}-dependence of the DIS structure functions
We consider in detail Q{sup 2}-dependence of the DIS structure functions. Very often this dependence is claimed to be originated by the Q{sup 2}-dependence of the QCD coupling. This leads to the small-x asymptotics of the structure functions with Q{sup 2}-dependent intercepts. We demonstrate that the DGLAP parametrization α{sub s} = α{sub s}(Q{sup 2}) is an approximation valid in the region of large x (where 2pq can be approximated by Q{sup 2}) only, providing the factorization scale is also large. Outside this region, the DGLAP parametrization fails, so α{sub s} should be replaced by an effective coupling which is independent of Q{sup 2} at small x. As a consequence, intercepts of the structure functions are independent of Q{sup 2}. Nevertheless, the small-x asymptotics of the structure functions explicitly depend on Q{sup 2}, even when the coupling does not depend on it. We also consider the structure functions at small Q{sup 2} and give a comment on power-Q{sup 2} corrections to the structure functions at large and small Q{sup 2}.
Measurements of the branching fractions for J / ψ and ψ ′ → Λ Λ ¯ π 0 and Λ Λ ¯ η
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Study of the near-threshold ω ϕ mass enhancement in doubly OZI-suppressed J / ψ → γ ω ϕ decays
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Search for η and η ′ → π + e − ν ¯ e + c . c . decays in J / ψ → ϕ η and ϕ η ′
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Search for hadronic transition χ cJ →η c π + π - and observation of χ cJ →KK̄ πππ
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Precision measurements of branching fractions for ψ ′ → π 0 J / ψ and η J / ψ
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