(Astro)-Particles Physics, Photo Conversion Materials, Student Lab and Education
المصدر:
PHYSICS LETTERS B Airapetian, A, Blok, H P, Hesselink, W H A, van der Nat, P B & Wang, S 2008, ' Measurement of parton distributions of strange quarks in the nucleon from charged-kaon production in deep-inelastic scattering on the deuteron ', Physics Letters B, vol. 666, no. 5, pp. 446-450 . https://doi.org/10.1016/j.physletb.2008.07.090 Physics letters / B 666, 446 (2008). doi:10.1016/j.physletb.2008.07.090 Physics Letters B, 666(5), 446-450. Elsevier
The momentum and helicity density distributions of the strange quark sea in the nucleon are obtained in leading order from charged-kaon production in deep-inelastic scattering on the deuteron. The distributions are extracted from spin-averaged K+/- multiplicities, and from K+/- and inclusive double-spin asymmetries for scattering of polarized positrons by a polarized deuterium target. The shape of the momentum distribution is softer than that of the average of the ubar and dbar quarks. In the region of measurement 0.02 < x < 0.6 and Q^2 > 1.0 GeV^2, the helicity distribution is zero within experimental uncertainties. 5 pages, 5 figures, 1 table; text slightly expanded, 10 references added