Dergi makalesi Açık Erişim

Search for a common baryon source in high-multiplicity pp collisions at the LHC

2020    CERN İşbirliği

We report on the measurement of the size of the particle-emitting source from two-baryon correlations with ALICE in high-multiplicity pp collisions at $\sqrt{s}=13$ TeV. The source radius is studied with low relative momentum p–p, $\stackrel{‾}{\text{p}}\phantom{\rule{0.25em}{0ex}}\text{–}\stackrel{‾}{\text{p}}\phantom{\rule{0.25em}{0ex}}$, p–Λ , and $\stackrel{‾}{\text{p}}\phantom{\rule{0.25em}{0ex}}\text{–}\stackrel{‾}{\Lambda }\phantom{\rule{0.25em}{0ex}}$ pairs as a function of the pair transverse mass ${m}_{T}$ considering for the first time in a quantitative way the effect of strong resonance decays. After correcting for this effect, the radii extracted for pairs of different particle species agree. This indicates that protons, antiprotons, Λ s, and $\stackrel{‾}{\Lambda }$ s originate from the same source. Within the measured ${m}_{T}$ range (1.1–2.2) GeV$/{c}^{2}$the invariant radius of this common source varies between 1.3 and 0.85 fm. These results provide a precise reference for studies of the strong hadron–hadron interactions and for the investigation of collective properties in small colliding systems.