The chargedparticle 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.
Twodimensional distribution of the change in log likelihood DLL($pK$) and DLL($p\pi$) for (a) protons, (b) kaons and (c) pions (here shown for negative tracks and one magnet polarity) in the calibration sample with $p_{\rm T} > 1.2$ GeV/$c$ and $3.5 < \eta \le 4.0$. The region indicated by the dotted lines in the top right corner of each plot is that which is selected in the analysis to isolate the proton sample. The selection of the calibration sample is discussed in Sect. ???. 
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Invariant mass distributions reconstructed for one magnet polarity from the $\sqrt{s}=7 \mathrm{TeV}$ data in the analysis bin for which the positive finalstate particle has $ p_{\rm T} \ge 1.2 {\rm GeV}$ and $3.5\le \eta<4.0$ for (a) $K^0_{\rm S} \rightarrow \pi^+\pi^$, (b) $\Lambda \rightarrow p \pi^$ and (c) $\phi \rightarrow K^+K^$. The results of unbinned maximum likelihood fits to the data are superimposed. 
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Monte Carlo PID efficiency study for protons (a), kaons (b) and pions (c). Shown is a comparison of measured efficiencies from a Monte Carlo calibration sample, after background subtraction and reweighting, with the true values in the Monte Carlo analysis sample. The diagonal line on each plot is drawn with unit gradient. 
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Results for the $\bar{p}/p$ ratio at 0.9 TeV (a) and 7 TeV (b). 
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Results for the $K^{}/K^{+}$ ratio at 0.9 TeV (a) and 7 TeV (b). 
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Results for the $\pi^{}/\pi^{+}$ ratio at 0.9 TeV (a) and 7 TeV (b). 
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Results for the $(p + \bar{p})/(\pi^+ + \pi^)$ ratio at 0.9 TeV (a) and 7 TeV (b). 
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Results for the $(K^+ + K^)/(\pi^+ + \pi^)$ ratio at 0.9 TeV (a) and 7 TeV (b). 
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Results for the $(p + \bar{p})/(K^+ + K^)$ ratio at 0.9 TeV (a) and 7 TeV (b). 
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Results for the $\bar{p}/p$ ratio against the rapidity loss $\Delta y$ from LHCb. Results from other experiments are also shown \cite{ALICEPBARP,ISR,BRAHMS, PHENIX,PHOBOS,STAR}. Superimposed is a fit to the LHCb and ALICE \cite{ALICEPBARP} measurements that is described in the text. 
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Animated gif made out of all figures. 
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Number of particle candidates in the analysis sample at $\sqrt{s}=0.9$ TeV, separated into positive and negative charge ($Q$). 
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Number of particle candidates in the analysis sample at $\sqrt{s}=7.0$ TeV, separated into positive and negative charge ($Q$). 
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Range of systematic uncertainties, in percent, for sameparticle ratios at $\sqrt{s}=0.9$ TeV. 
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Range of systematic uncertainties, in percent, for sameparticle ratios at $\sqrt{s}=7$ TeV. 
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Range of systematic uncertainties, in percent, for differentparticle ratios at $\sqrt{s}=0.9$ TeV. 
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Range of systematic uncertainties, in percent, for differentparticle ratios at $\sqrt{s}=7$ TeV. 
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Results for $\bar{p}/p$ ratio integrated over $p_{\rm T}$ in $\eta$ bins as a function of the rapidity loss $\Delta y$. 
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Results for the $\bar{p}/p$ ratio with statistical and systematic uncertainties, as a function of $p_{\rm T}$ and $\eta$. Also shown is the mean rapidity, $y$, and RMS spread for the sample in each $\eta$ bin. 
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Results for the $K^/K^+$ ratio with statistical and systematic uncertainties, as a function of $p_{\rm T}$ and $\eta$. Also shown is the mean rapidity, $y$, and RMS spread for the sample in each $\eta$ bin. 
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Results for the $\pi^/\pi^+$ ratio with statistical and systematic uncertainties, as a function of $p_{\rm T}$ and $\eta$. Also shown is the mean rapidity, $y$, and RMS spread for the sample in each $\eta$ bin. 
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Results for the $(p + \bar{p})/(\pi^+ + \pi^)$ ratio with statistical and systematic uncertainties, as a function of $p_{\rm T}$ and $\eta$. 
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Results for the $(K^+ + K^)/(\pi^+ + \pi^)$ ratio with statistical and systematic uncertainties, as a function of $p_{\rm T}$ and $\eta$. 
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Results for the $(p + \bar{p})/(K^+ + K^)$ ratio with statistical and systematic uncertainties, as a function of $p_{\rm T}$ and $\eta$. 
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Created on 20 February 2021.