Meson twist - 4 parton distributions in terms of twist - 2 distribution amplitudes at large N c
نویسنده
چکیده
In this particular isospin combination of structure functions the contribution of twist-2 operators cancels out exactly and twist-4 contributions are dominant. It is remarkable that in the large Nc limit the twist-4 distribution function of quarks in the pion can be reduced to a convolution of twist-2 pion distribution amplitudes. 2. One can read the contribution of four-quark twist-4 operators to F2 from [4, 5] (correcting obvious misprints)
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