0 v 3 2 2 Ju l 2 00 7 Scalar form - factors f ππ ( Q 2 ) and f KK ( Q 2 ) with light - cone QCD sum rules
نویسنده
چکیده
In this article, we calculate the scalar form-factors fππ(Q 2) and fKK(Q 2) in the framework of the light-cone QCD sum rules approach. The numerical value of the fππ(Q 2) changes quickly with variation ofQ2 near zero momentum transfer, while the fKK(Q 2) has rather good behavior at small momentum transfer. The value fKK(0) = 2.21 +0.35 −0.19GeV is compatible with the result from the leading order chiral perturbation theory. At large momentum transfer with Q2 > 6GeV 2, the form-factor fππ(Q 2) takes up the asymptotic behavior 1 Q approximately, while the fKK(Q 2) decreases more quickly than 1 Q . PACS numbers: 12.38.Lg; 12.38.Bx
منابع مشابه
0 v 2 1 0 M ay 2 00 7 Scalar form factors f ππ ( Q 2 ) and f KK ( Q 2 ) with light - cone QCD sum rules
In this article, we calculate the scalar form factors fππ(Q 2) and fKK(Q 2) within the framework of the light-cone QCD sum rules approach. The numerical value of fππ(Q 2) changes quickly with variation of Q2 near zero momentum transfer, while the fKK(Q 2) has rather good behavior at small momentum transfer. The value fKK(0) = 2.21 +0.35 −0.19GeV is compatible with the values from the leading or...
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In this article, we calculate the scalar form factors fππ(Q 2) and fKK(Q 2) within the framework of the light-cone QCD sum rules approach. The numerical value of fππ(Q 2) changes quickly with the variation of Q2 at about Q2 < 0.1GeV 2, while fKK(Q 2) has rather good behavior at small momentum transfer, the value fKK(0) = 2.21 +0.35 −0.19GeV is compatible with the values from the leading order c...
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