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تسجيل مستخدم جديدMeasurement of prompt hadron production ratios in $pp$ collisions at $sqrt{s} = $ 0.9 and 7 TeV
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The charged-particle production ratios $bar{p}/p$, $K^-/K^+$, $pi^-/pi^+$, $(p + bar{p})/(pi^+ + pi^-)$, $(K^+ + K^-)/(pi^+ + pi^-)$ and $(p + bar{p})/(K^+ + K^-)$ are measured with the LHCb detector using $0.3 {rm nb^{-1}}$ of $pp$ collisions delivered by the LHC at $sqrt{s} = 0.9$ TeV and $1.8 {rm nb^{-1}}$ at $sqrt{s} = 7$ TeV. The measurements are performed as a function of transverse momentum $p_{rm T}$ and pseudorapidity $eta$. The production ratios are compared to the predictions of several Monte Carlo generator settings, none of which are able to describe adequately all observables. The ratio $bar{p}/p$ is also considered as a function of rapidity loss, $Delta y equiv y_{rm beam} - y$, and is used to constrain models of baryon transport.
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