v 2 3 1 M ay 2 00 1 Leading twist asymmetries in deeply virtual Compton scattering
نویسندگان
چکیده
We calculate spin, charge, and azimuthal asymmetries in deeply virtual Compton scattering at leading twist-two level. The measurement of these asymmetries gives access to the imaginary and real part of all deeply virtual Compton scattering amplitudes. We note that a consistent description of this process requires taking into account twist-three contributions and we give then a model dependent estimate of these asymmetries.
منابع مشابه
M ar 2 00 1 Twist - three observables in deeply virtual Compton scattering on the nucleon
We study twist-three effects in deeply virtual Compton scattering on an unpolarized spin-1/2 target. A careful definition of observables as Fourier moments w.r.t. the azimuthal angle allows for a clear separation of twist-two and-three effects. Although the latter are power suppressed, they give leading contributions to the twist-three asymmetries and do not affect the twist-two observables.
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We compute amplitude of deeply virtual Compton scattering in the parton model. We found that the amplitude in the hard regime up to the accuracy O(1/Q) depends on new skewed parton distributions (SPD's). These additional contributions make the DVCS amplitude explicitly transverse. The new SPD's contribute to various spin, charge and azimuthal asymmetries at the same order in 1/Q as the leading ...
متن کامل0 Leading twist asymmetries in deeply virtual Compton scattering
We calculate spin, charge, and azimuthal asymmetries in deeply virtual Compton scattering at leading twist-two level. The measurement of these asymmetries gives access to the imaginary and real part of all deeply virtual Compton scattering amplitudes. We note that a consistent description of this process requires taking into account twist-three contributions and we give then a model dependent e...
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