d̄ − ū asymmetry and semi - inclusive production of pions in DIS
نویسندگان
چکیده
¯ d − ¯ u asymmetry and semi-inclusive production of pions in DIS Abstract We investigate unambiguities in the extraction of the ¯ d − ¯ u asymmetry from semi-inclusive production of pions in DIS. The role of several effects beyond the quark-parton model (QPM) which lead to N π + p = N π + n and N π − p = N π − n and may therefore cloud such an extraction is studied. The results are discussed in the context of the recent HERMES data. We find that the interaction of the resolved photon with the nucleon significantly modifies the observed ¯ d − ¯ u asymmetry. The exclusive elastic production of ρ mesons plays a similar role for the large-z data sample. Our estimate shows a rather small effect of the spectator mechanism. Nuclear effects in the deuteron also look potentially important but are difficult to estimate quantitatively. Throughout the paper we make in addition several general remarks concerning semi-inclusive and exclusive production of mesons.
منابع مشابه
0 Semi - inclusive production of pions in DIS and d̄ − ū asymmetry
We discuss the role of some nonpartonic effects which lead to N π + p = N π + n and N π − p = N π − n and may therefore modify the conclusion on the ¯ d − ¯ u asymmetry extracted from semi-inclusive production of pions in DIS. Quantitative estimations for resolved photon and exclusive ρ 0 are given as examples. The results are discussed in the context of recent HERMES data.
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