QCD sum rule calculation of transition form factor
نویسندگان
چکیده
منابع مشابه
QCD Sum Rule Calculation of γγ ∗ → π 0 Transition Form Factor
We develop a QCD sum rule analysis of the form factor F γ * γ * π • (q 2 , Q 2) in the region where virtuality of one of the spacelike photons is small q 2 ≪ 1 GeV 2 while another is large: Q 2 > ∼ 1 GeV 2. We construct the operator product expansion suitable for this kinematic situation and obtain a QCD sum rule for F γ * γ * π • (0, Q 2). Our results confirm expectation that the momentum tran...
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The transition γ * (q 1)γ * (q 2) → π • (p) is studied within the QCD sum rule framework. As a first step, we analyze the kinematic situation when both photon virtualities are spacelike and large. We construct a QCD sum rule for F γ * γ * π • (q 2 1 , q 2 2) and show that, in the asymptotic limit |q 2 1 |, |q 2 2 | → ∞, it reproduces the leading-order pQCD result. Then we study the limit |q 2 1...
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ژورنال
عنوان ژورنال: Physics Letters B
سال: 1996
ISSN: 0370-2693
DOI: 10.1016/0370-2693(96)00175-x