Constraints on the large-x d/u ratio from electron--nucleus scattering at x>1

doi:10.1103/PhysRevD.84.117501

Title: Constraints on the large-x d/u ratio from electron--nucleus scattering at x>1

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Abstract

Recently the ratio of neutron to proton structure functions F{sub 2}{sup n}/F{sub 2}{sup p} was extracted from a phenomenological correlation between the strength of the nuclear EMC effect and inclusive electron-nucleus cross section ratios at x > 1. Within conventional models of nuclear smearing, this 'in-medium correction' (IMC) extraction constrains the size of nuclear effects in the deuteron structure functions, from which the neutron structure function F{sub 2}{sup n} is usually extracted. The IMC data determine the resulting proton d/u quark distribution ratio, extrapolated to x = 1, to be 0.23 {+-} 0.09 with a 90% confidence level. This is well below the SU(6) symmetry limit of 1/2 and significantly above the scalar diquark dominance limit of 0.

Authors:: O. Hen, A. Accardi, W. Melnitchouk and E. Piasetzky

Publication Date:: Thu Dec 01 00:00:00 EST 2011

Research Org.:: Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

Sponsoring Org.:: USDOE Office of Science (SC)

OSTI Identifier:: 1033511

Report Number(s):: JLAB-THY-11-1447; DOE/OR/23177-1867; arXiv:1110.2419
Journal ID: ISSN 1550-7998; TRN: US1200340

DOE Contract Number:: AC05-06OR23177

Resource Type:: Journal Article

Journal Name:: Physical Review. D, Particles, Fields, Gravitation and Cosmology

Additional Journal Information:: Journal Volume: 84; Journal Issue: 11; Journal ID: ISSN 1550-7998

Country of Publication:: United States

Language:: English

Subject:: 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; CROSS SECTIONS; DEUTERONS; DISTRIBUTION; EMC EFFECT; NEUTRONS; PROTONS; QUARKS; SCALARS; SCATTERING; STRUCTURE FUNCTIONS; SYMMETRY

Citation Formats


                    O. Hen, A. Accardi, W. Melnitchouk and E. Piasetzky. Constraints on the large-x d/u ratio from electron--nucleus scattering at x>1.  United States: N. p., 2011. 
        Web.  doi:10.1103/PhysRevD.84.117501.

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                    O. Hen, A. Accardi, W. Melnitchouk and E. Piasetzky. Constraints on the large-x d/u ratio from electron--nucleus scattering at x>1.  United States.  https://doi.org/10.1103/PhysRevD.84.117501

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                    O. Hen, A. Accardi, W. Melnitchouk and E. Piasetzky. 2011.  
        "Constraints on the large-x d/u ratio from electron--nucleus scattering at x>1".  United States.  https://doi.org/10.1103/PhysRevD.84.117501.  https://www.osti.gov/servlets/purl/1033511.

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@article{osti_1033511,

  title        = {Constraints on the large-x d/u ratio from electron--nucleus scattering at x>1},

  author       = {O. Hen, A. Accardi, W. Melnitchouk and E. Piasetzky},

  abstractNote = {Recently the ratio of neutron to proton structure functions F{sub 2}{sup n}/F{sub 2}{sup p} was extracted from a phenomenological correlation between the strength of the nuclear EMC effect and inclusive electron-nucleus cross section ratios at x > 1. Within conventional models of nuclear smearing, this 'in-medium correction' (IMC) extraction constrains the size of nuclear effects in the deuteron structure functions, from which the neutron structure function F{sub 2}{sup n} is usually extracted. The IMC data determine the resulting proton d/u quark distribution ratio, extrapolated to x = 1, to be 0.23 {+-} 0.09 with a 90% confidence level. This is well below the SU(6) symmetry limit of 1/2 and significantly above the scalar diquark dominance limit of 0.},

  doi          = {10.1103/PhysRevD.84.117501},

  url          = {https://www.osti.gov/biblio/1033511},
  journal      = {Physical Review. D, Particles, Fields, Gravitation and Cosmology},

  issn         = {1550-7998},

  number       = 11,

  volume       = 84,

  place        = {United States},

  year         = {Thu Dec 01 00:00:00 EST 2011},

  month        = {Thu Dec 01 00:00:00 EST 2011}

}

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