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The European Physical Journal C

, Volume 58, Issue 1, pp 29–35 | Cite as

Comment on the recent COMPASS data on the spin structure function g 1

  • B. I. Ermolaev
  • M. GrecoEmail author
  • S. I. Troyan
Regular Article - Theoretical Physics

Abstract

We examine the recent COMPASS data on the spin structure function g 1 singlet. We show that it is rather difficult to use the data in the present form in order to draw conclusions on the initial parton densities. However, our tentative estimate is that the data better agree with positive than with negative initial gluon densities.

PACS

12.38.Cy 

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Copyright information

© Springer-Verlag / Società Italiana di Fisica 2008

Authors and Affiliations

  1. 1.Ioffe Physico-Technical InstituteSt. PetersburgRussia
  2. 2.Department of Physics and INFNUniversity Rome IIIRomeItaly
  3. 3.St. Petersburg Institute of Nuclear PhysicsGatchinaRussia

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