The Second Moment of the Structure Function for Pseudoscalar Mesons in QCD Sum Rules
نویسنده
چکیده
We calculate the values of the second moment M s 2 of the flavorsinglet structure function F s 2 for the pion and the kaon in QCD sum rules, and investigate how the results depend on their flavor structure (quark contents). Our calculations give similar values of M s 2 for these two mesons, because of cancellation among several non-small factors. We emphasize that decay constants, meson masses and quark masses play an essential role in the above cancellation.
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