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Measurement of the double longitudinal spin asymmetry in inclusive jet production in polarized p+p collisions at sqrt(s) = 200 GeV

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 نشر من قبل Joanna Kiryluk
 تاريخ النشر 2005
  مجال البحث
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 تأليف Joanna Kiryluk




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We present preliminary results for the first measurements of the double longitudinal spin asymmetry A_LL in inclusive jet production at mid-rapidity in polarized proton-proton collisions at sqrt(s) = 200 GeV. The data amount to ~ 0.5 pb-1 collected at RHIC in 2003 and 2004 with beam polarizations up to 45%. The jet transverse energies are in the range of 5 < pT < 17 GeV/c. The data are consistent with theoretical evaluations using deep-inelastic scattering parametrizations for gluon polarization in the nucleon, and tend to disfavor large positive values of gluon polarization.



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