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Azimuthal asymmetries in production of charged hadrons by high energy muons on polarized deuterium targets

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 نشر من قبل Anatoly Efremov
 تاريخ النشر 2010
  مجال البحث
والبحث باللغة English
 تأليف I.A. Savin




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Search for azimuthal asymmetries in semi-inclusive production of charged hadrons by 160 GeV muons on the longitudinally polarized deuterium target, has been performed using the 2002- 2004 COMPASS data. The observed asymmetries integrated over the kinematical variables do not depend on the azimuthal angle of produced hadrons and are consistent with the ratio $g_1^d(x)/f_1^d(x)$. The asymmetries are parameterized taking into account possible contributions from different parton distribution functions and parton fragmentation functions depending on the transverse spin of quarks.They can be modulated (either/or/and) with $sin(phi), sin(2phi), sin(3phi)$ and $cos(phi)$. The $x$-, $z$- and $p_h^T$-dependencies of these amplitudes are studied.



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