Soft and hard pomerons
نویسنده
چکیده
Regge theory provides an excellent description of small-x structurefunction data from Q = 0 up to the highest available values. The large-Q data should also be described by perturbative QCD: the two descriptions must agree in the region where they overlap. However, at present there is a serious lack in our understanding of how to apply perturbative QCD at small x. The usual lowestorder or next-to-lowest order expansion is not valid, at least not until Q becomes much larger than is usually assumed; a resummation is necessary, but as yet we do not know how to do this resummation.
منابع مشابه
ar X iv : h ep - p h / 05 11 07 3 v 1 7 N ov 2 00 5 The soft and the hard pomerons in hadron elastic scattering at small t
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