Invariant-mass distribution for the $\overline{ \Lambda} \rightarrow \overline p \pi ^+ $ candidates selected in the $ p {\rm He}$ data. The fit model is overlaid on the data.

Normalised distributions of the production vertex $z$ coordinate for simulated prompt and detached $\overline p $ in $ p {\rm He}$ collisions and for prompt $\overline p $ in simulated $ p $ $ p $ collisions in the kinematic range explored in this paper. The PV fiducial region for $ p {\rm He}$ collisions is $-700 < z < 100$ $\text{ mm}$ .

VELO tracking efficiency for $\overline p $ in $\overline{ \Lambda} \rightarrow \overline p \pi ^+ $ decays as a function of (top left) the particle momentum, (top right) the transverse momentum, (bottom left) the production vertex $z$ coordinate and (bottom right) the number of reconstructed long tracks in the event.

Measured $ R_{\overline{ \Lambda} }$ in each of the considered $ p$ and $ p_{\mathrm{T}}$ intervals.

Measured $ R_{\overline{ \Lambda} }$ as a function of (top) the $\overline p $ momentum for $0.55< p_{\mathrm{T}} <1.2$ $\text{ Ge V /}c$ and (bottom) the $\overline p $ transverse momentum for $12< p <50.5$ $\text{ Ge V /}c$ . The measurement is compared to the predictions, in the same kinematic regions, from the Epos 1.99 [34], Epos-lhc [23], Hijing 1.38 [35] and Pythia 6 [36] models, included in the Crmc package [27]. Error bars on data represent the total uncertainty.

Distributions of the $\log(\chi^2_{\text{IP}} )$ variable for all simulated antiprotons in the $\overline p $ -enriched simulated sample. The contributions from prompt, detached and antiprotons produced in the detector material are separately shown.

Distributions of $\log(\chi^2_{\text{IP}} )$ for (top) prompt and (bottom) detached antiprotons in the $\overline p $ -enriched simulated sample for a kinematic interval in the central region of the considered phase-space. The fit model is overlaid on the data.

Distributions of the $\log(\chi^2_{\text{IP}} )$ variable in the data sample integrated over all kinematic intervals. The fit model is overlaid on the data.

Normalised distributions of the prompt $\overline p $ $\log(\chi^2_{\text{IP}} )$ variable in different ranges of the azimuthal angle $\phi=\text{atan}(p_y/p_x)$.

Sketch of the VELO [37], where the aluminium foils crossed by the particles before entering the VELO volume is visible. The crossed material is maximum for $|\phi| > 1$.

Invariant-mass distributions for the $\overline{ \Lambda} (1520) \rightarrow \overline p K ^+ $ candidates selected in the $ p {\rm Ne}$ data within two intervals of the $\overline p $ $\log(\chi^2_{\text{IP}} )$ variable. The fit model is overlaid on the data.

Distributions of the number of signal candidates determined in each interval of the antiproton $\log(\chi^2_{\text{IP}} )$ compared to the prediction of the $ p {\rm He}$ simulation for selected prompt antiprotons.

Distribution of the $\log(\chi^2_{\text{IP}} )$ variable in the data sample integrated over all kinematic intervals modelled with independent components for $\overline{ \Sigma } {}^-$ decays (labelled as $\overline p $ from $\overline{ \Sigma } {}^-$ ) and all other antihyperon decays ( $\overline p $ from $\overline{ \Lambda}$ ).

Invariant-mass distribution for the $\overline{ \Xi } ^+ \rightarrow \overline{ \Lambda} \pi ^+ $ candidates selected in the $ p {\rm He}$ data. The fit model is overlaid on the data.

Measured $ R_{\overline{ H} }$ in each of the considered $ p$ and $ p_{\mathrm{T}}$ intervals.

Measured $ R_{\overline{ H} }$ as a function of (top) the $\overline p $ momentum for $0.4< p_{\mathrm{T}} <4\text{ Ge V /}c $ and (bottom) the $\overline p $ transverse momentum for $12< p <110\text{ Ge V /}c $. The measurement is compared to predictions, in the same kinematic regions, from the Epos 1.99 [34], Epos-lhc [23], Hijing 1.38 [35], Pythia 6 [36] and Qgsjet-ii04 [39] models, included in the Crmc package [27]. Error bars on data represent the total uncertainty.

Fraction of antiprotons from decays of promptly produced $\overline{ \Lambda}$ particles to the total yield of detached antiprotons as a function of (top) their momentum for $0.55< p_{\mathrm{T}} <1.2\text{ Ge V /}c $ and (bottom) their transverse momentum for $12< p <50.5\text{ Ge V /}c $. The data are compared to the Epos-lhc [23] prediction for this quantity. Error bars on data represent the total uncertainty.

Animated gif made out of all figures.

Selection requirements for $\overline{ \Lambda} \rightarrow \overline p \pi ^+ $ decays. Symbols are defined in the text.

Relative uncertainties on the $ R_{\overline{ \Lambda} }$ measurement.

Relative uncertainties on the $ R_{\overline{ H} }$ measurement.

Measured $ R_{\overline{ H} }$ and $ R_{\overline{ \Lambda} }$ ratios in intervals of the antiproton momentum and transverse momentum, measured in $\text{ Ge V /}c$ units. The average momentum and transverse momentum, as predicted by the Epos-lhc generator for prompt antiprotons, are also listed for each interval in $\text{ Ge V /}c$ units. The uncertainty is split into an uncorrelated component, denoted with $\delta _{\text{uncorr}} $, and a component that is fully correlated among the kinematic intervals, denoted $\delta _{\text{corr}} $.