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تسجيل مستخدم جديدLongitudinal double-spin asymmetry for inclusive jet and dijet production in polarized proton collisions at $sqrt{s}=200$ GeV
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We report high-precision measurements of the longitudinal double-spin asymmetry, $A_{LL}$, for midrapidity inclusive jet and dijet production in polarized $pp$ collisions at a center-of-mass energy of $sqrt{s}=200,mathrm{GeV}$. The new inclusive jet data are sensitive to the gluon helicity distribution, $Delta g(x,Q^2)$, for gluon momentum fractions in the range from $x simeq 0.05$ to $x simeq 0.5$, while the new dijet data provide further constraints on the $x$ dependence of $Delta g(x,Q^2)$. The results are in good agreement with previous measurements at $sqrt{s}=200,mathrm{GeV}$ and with recent theoretical evaluations of prior world data. Our new results have better precision and thus strengthen the evidence that $Delta g(x,Q^2)$ is positive for $x > 0.05$.
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We report a new high-precision measurement of the mid-rapidity inclusive jet longitudinal double-spin asymmetry, $A_{LL}$, in polarized $pp$ collisions at center-of-mass energy $sqrt{s}=200$ GeV. The STAR data place stringent constraints on polarized
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We report the first measurement of the inclusive jet and the dijet longitudinal double-spin asymmetries, $A_{LL}$, at midrapidity in polarized $pp$ collisions at a center-of-mass energy $sqrt{s} = 510$ GeV. The inclusive jet $A_{LL}$ measurement is s
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We report a measurement of the longitudinal double-spin asymmetry A_LL and the differential cross section for inclusive midrapidity jet production in polarized proton collisions at sqrt(s)=200 GeV. The cross section data cover transverse momenta 5 <
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We present the first measurements of the longitudinal double-spin asymmetry $A_{LL}$ for dijets with at least one jet reconstructed within the pseudorapidity range $0.8 < eta < 1.8$. The dijets were measured in polarized $pp$ collisions at a center-o
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These proceedings show the preliminary results of the dijet cross sections and the dijet longitudinal double spin asymmetries A_LL in polarized proton-proton collisions at sqrt{s} = 200 GeV at the mid-rapidity |eta| < 0.8. The integrated luminosity o
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