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Observation of Transverse Spin-Dependent Azimuthal Correlations of Charged Pion Pairs in $p^uparrow+p$ at $sqrt{s}=200$ GeV

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 نشر من قبل Anselm Vossen
 تاريخ النشر 2015
  مجال البحث
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We report the observation of transverse polarization-dependent azimuthal correlations in charged pion pair production with the STAR experiment in $p^uparrow+p$ collisions at RHIC. These correlations directly probe quark transversity distributions. We measure signals in excess of five standard deviations at high transverse momenta, at high pseudorapidities eta>0.5, and for pair masses around the mass of the rho-meson. This is the first direct transversity measurement in p+p collisions. Comparing the results to data from lepton-nucleon scattering will test the universality of these spin-dependent quantities.



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