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Quark Helicity Distributions from Longitudinal Spin Asymmetries in Muon-Proton and Muon-Deuteron Scattering
We present a leading order evaluation of the helicity distributions for the three lightest quarks and anti-quarks flavours, derived from the double-spin asymmetries measured by the COMPASS collaboration. The data, obtained by scattering a 160 GeV muon beam off longitudinally polarised NH$_{3}$ and...
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Lenguaje: | eng |
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2011
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Acceso en línea: | https://dx.doi.org/10.1088/1742-6596/295/1/012069 http://cds.cern.ch/record/1494629 |
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author | Windmolders, R |
author_facet | Windmolders, R |
author_sort | Windmolders, R |
collection | CERN |
description | We present a leading order evaluation of the helicity distributions for the three lightest quarks and anti-quarks flavours, derived from the double-spin asymmetries measured by the COMPASS collaboration. The data, obtained by scattering a 160 GeV muon beam off longitudinally polarised NH$_{3}$ and $^{6}$LiD targets, cover the Bjorken variable $x$ range 0.004 $< x <$ 0.7. The resulting values of the sea quark distributions are all small and do not show any sizable dependence on $x$ in the range of the measurements. No significant difference is observed between the strange and anti-strange helicity distributions, both compatible with zero. The integrated value of the polarised flavour sea asymmetry is found to be slightly positive, about 1.5 standard deviations away from zero. |
id | cern-1494629 |
institution | Organización Europea para la Investigación Nuclear |
language | eng |
publishDate | 2011 |
record_format | invenio |
spelling | cern-14946292022-08-17T13:30:07Zdoi:10.1088/1742-6596/295/1/012069http://cds.cern.ch/record/1494629engWindmolders, RQuark Helicity Distributions from Longitudinal Spin Asymmetries in Muon-Proton and Muon-Deuteron ScatteringParticle Physics - ExperimentWe present a leading order evaluation of the helicity distributions for the three lightest quarks and anti-quarks flavours, derived from the double-spin asymmetries measured by the COMPASS collaboration. The data, obtained by scattering a 160 GeV muon beam off longitudinally polarised NH$_{3}$ and $^{6}$LiD targets, cover the Bjorken variable $x$ range 0.004 $< x <$ 0.7. The resulting values of the sea quark distributions are all small and do not show any sizable dependence on $x$ in the range of the measurements. No significant difference is observed between the strange and anti-strange helicity distributions, both compatible with zero. The integrated value of the polarised flavour sea asymmetry is found to be slightly positive, about 1.5 standard deviations away from zero.oai:cds.cern.ch:14946292011 |
spellingShingle | Particle Physics - Experiment Windmolders, R Quark Helicity Distributions from Longitudinal Spin Asymmetries in Muon-Proton and Muon-Deuteron Scattering |
title | Quark Helicity Distributions from Longitudinal Spin Asymmetries in Muon-Proton and Muon-Deuteron Scattering |
title_full | Quark Helicity Distributions from Longitudinal Spin Asymmetries in Muon-Proton and Muon-Deuteron Scattering |
title_fullStr | Quark Helicity Distributions from Longitudinal Spin Asymmetries in Muon-Proton and Muon-Deuteron Scattering |
title_full_unstemmed | Quark Helicity Distributions from Longitudinal Spin Asymmetries in Muon-Proton and Muon-Deuteron Scattering |
title_short | Quark Helicity Distributions from Longitudinal Spin Asymmetries in Muon-Proton and Muon-Deuteron Scattering |
title_sort | quark helicity distributions from longitudinal spin asymmetries in muon-proton and muon-deuteron scattering |
topic | Particle Physics - Experiment |
url | https://dx.doi.org/10.1088/1742-6596/295/1/012069 http://cds.cern.ch/record/1494629 |
work_keys_str_mv | AT windmoldersr quarkhelicitydistributionsfromlongitudinalspinasymmetriesinmuonprotonandmuondeuteronscattering |