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تسجيل مستخدم جديدMeasurement of neutral mesons in p+p collisions at sqrt(s) = 200 GeV and scaling properties of hadron production
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The PHENIX experiment at the Relativistic Heavy Ion Collider has measured the invariant differential cross section for production of K^0_S , omega, eta prime, and phi mesons in p + p collisions at = 200 GeV. Measurements omega and phi production in different decay channels give consistent results. New results for the phi are in agreement with previously published data and extend the measured pT coverage. The spectral shapes of all hadron transverse momentum distributions measured by PHENIX are well described by a Tsallis distribution functional form with only two parameters, n and T, determining the high-pT and characterizing the low-pT regions of the spectra, respectively. The values of these parameters are very similar for all analyzed meson spectra, but with a lower parameter T extracted for protons. The integrated invariant cross sections calculated from the fitted distributions are found to be consistent with existing measurements and with statistical model predictions.
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