Power corrections in the longitudinal and transverse structure functions of proton and deuteron Original Research Article

wer corrections to the Q2 behaviour of the low-order moments of both the longitudinal and transverse structure functions of the proton and deuteron have been investigated using available phenomenological fits of existing data in the Q2 range between 1 and 20 (GeV/c)2. The Nachtmann definition of the moments has been adopted for disentangling properly target-mass and dynamical higher-twist effects in the data. The leading twist has been treated at next-to-leading order in the strong coupling constant and the effects of higher orders of the perturbative series have been estimated using a renormalon-inspired model. The contributions of (target-dependent) multiparton correlations to both 1/Q2 and 1/Q4 power terms have been determined in the transverse channel, while the longitudinal one appears to be consistent with a pure infrared renormalon picture in the whole Q2-range between 1 and 20 (GeV/c)2. Finally, the extracted twist-2 contribution in the deuteron turns out to be compatible with the hypothesis of an enhanced d-quark parton distribution at large x.