# Measurement of prompt hadron production ratios in $pp$ collisions at $\sqrt{s} =$ 0.9 and 7 TeV

Abstract : 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.
docType_s :
Journal articles
European Physical Journal C: Particles and Fields, EDP Sciences: EPJ, 2012, 72, pp.2168. <10.1140/epjc/s10052-012-2168-x>
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http://hal.in2p3.fr/in2p3-00711512
Contributor : Françoise Marechal <>
Submitted on : Monday, June 25, 2012 - 11:00:27 AM
Last modification on : Monday, November 26, 2012 - 2:00:58 PM

### Citation

R. Aaij, S. Barsuk, O. Callot, J. He, B. Jean-Marie, et al.. Measurement of prompt hadron production ratios in $pp$ collisions at $\sqrt{s} =$ 0.9 and 7 TeV. European Physical Journal C: Particles and Fields, EDP Sciences: EPJ, 2012, 72, pp.2168. <10.1140/epjc/s10052-012-2168-x>. <in2p3-00711512>

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