Impact of CLAS and COMPASS data on Polarized Parton Densities and Higher Twist

Abstract

We have re-analyzed the world data on inclusive polarized DIS including the very precise CLAS proton and deuteron data, as well as the latest COMPASS data on the asymmetry $A_1^d$, and have studied the impact of these data on polarized parton densities and higher twist effects. We demonstrate that the low $Q^2$ CLAS data improve essentially our knowledge of higher twist corrections to the spin structure function $g_1$, while the large $Q^2$ COMPASS data influence mainly the strange quark density. In our new analysis we find that a negative polarized gluon density, or one that changes sign as a function of x, cannot be ruled out from the present DIS data.

Version to be published in Phys. Rev. D., minor changes in the text, 2 figures and 2 references added

References in corpus (2)

• Constraint on Δg(x) from π^0 production at RHIC
• Higher-twist analysis of moments of spin structure function

Cited by in corpus (14)

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• Spin Structure of the Nucleon - Status and Recent Results
• Interplay of Spin and Orbital Angular Momentum in the Proton
• Determination of gluon polarization from deep inelastic scattering and collider data
• Experimental study of isovector spin sum rules
• Bjorken Sum Rule and pQCD frontier on the move
• Polarized DIS in N=4 SYM: Where is spin at strong coupling?
• Spin and orbital angular momentum of the proton
• The proton spin puzzle: where are we today ?
• Longitudinal polarization of hyperon and anti-hyperon in semi-inclusive deep-inelastic scattering
• Some Remarks on Methods of QCD Analysis of Polarized DIS Data
• Anti-Hyperon polarization in high energy pp collisions with polarized beams
• Extraction of characteristic constants in QCD with perturbative and nonperturbative methods
• Target mass corrections to matrix elements in nucleon spin structure functions