The production of strange hadrons (
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Underlying-event properties in pp and p–Pb collisions at $$ \sqrt{s_{\textrm{NN}}} $$ = 5.02 TeV
A bstract We report about the properties of the underlying event measured with ALICE at the LHC in pp and p–Pb collisions at $$ \sqrt{s_{\textrm{NN}}} $$ s NN = 5 . 02 TeV. The event activity, quantified by charged-particle number and summed- p T densities, is measured as a function of the leading-particle transverse momentum $$ \left({p}_{\textrm{T}}^{\textrm{trig}}\right) $$ p T trig . These quantities are studied in three azimuthal-angle regions relative to the leading particle in the event: toward, away, and transverse. Results are presented for three different p T thresholds (0.15, 0.5 and 1 GeV/ c ) at mid-pseudorapidity (| η | < 0 . 8). The event activity in the transverse region, which is the most sensitive to the underlying event, exhibits similar behaviour in both pp and p–Pb collisions, namely, a steep increase with $$ {p}_{\textrm{T}}^{\textrm{trig}} $$ p T trig for low $$ {p}_{\textrm{T}}^{\textrm{trig}} $$ p T trig , followed by a saturation at $$ {p}_{\textrm{T}}^{\textrm{trig}}\approx 5 $$ p T trig ≈ 5 GeV/ c . The results from pp collisions are compared with existing measurements at other centre-of-mass energies. The quantities in the toward and away regions are also analyzed after the subtraction of the contribution measured in the transverse region. The remaining jet-like particle densities are consistent in pp and p–Pb collisions for $$ {p}_{\textrm{T}}^{\textrm{trig}}>10 $$ p T trig > 10 GeV/ c , whereas for lower $$ {p}_{\textrm{T}}^{\textrm{trig}} $$ p T trig values the event activity is slightly higher in p–Pb than in pp collisions. The measurements are compared with predictions from the PYTHIA 8 and EPOS LHC Monte Carlo event generators.
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- NSF-PAR ID:
- 10433319
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Date Published:
- Journal Name:
- Journal of High Energy Physics
- Volume:
- 2023
- Issue:
- 6
- ISSN:
- 1029-8479
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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