Measurements of charged-particle production in pp, p–Pb, and Pb–Pb collisions in the toward, away, and transverse regions with the ALICE detector are discussed. These regions are defined event-by-event relative to the azimuthal direction of the charged trigger particle, which is the reconstructed particle with the largest transverse momentum
Measurements of the production of electrons from heavy-flavour hadron decays in pp collisions at
- PAR ID:
- 10486929
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Springer
- Date Published:
- Journal Name:
- Journal of High Energy Physics
- Volume:
- 2023
- Issue:
- 8
- ISSN:
- 1029-8479
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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A<sc>bstract</sc> $$ \left({p}_{\textrm{T}}^{\textrm{trig}}\right) $$ < $$ {p}_{\textrm{T}}^{\textrm{trig}} $$ < 15 GeV/c . The toward and away regions contain the primary and recoil jets, respectively; both regions are accompanied by the underlying event (UE). In contrast, the transverse region perpendicular to the direction of the trigger particle is dominated by the so-called UE dynamics, and includes also contributions from initial- and final-state radiation. The relative transverse activity classifier,$$ {R}_{\textrm{T}}={N}_{\textrm{ch}}^{\textrm{T}}/\left\langle {N}_{\textrm{ch}}^{\textrm{T}}\right\rangle $$ $$ {N}_{\textrm{ch}}^{\textrm{T}} $$ $$ \left\langle {N}_{\textrm{ch}}^{\textrm{T}}\right\rangle $$ R Tdistributions in pp collisions at$$ \sqrt{s} $$ . 76, 5.02, 7, and 13 TeV is reported, exploring the Koba-Nielsen-Olesen (KNO) scaling properties of the multiplicity distributions. The first measurements of charged-particlep Tspectra as a function ofR Tin the three azimuthal regions in pp, p–Pb, and Pb–Pb collisions at$$ \sqrt{s_{\textrm{NN}}} $$ . 02 TeV are also reported. Data are compared with predictions obtained from the event generators PYTHIA 8 and EPOS LHC. This set of measurements is expected to contribute to the understanding of the origin of collective-like effects in small collision systems (pp and p–Pb). -
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A<sc>bstract</sc> The production of strange hadrons (
$$ {\textrm{K}}_{\textrm{S}}^0 $$ ± , and Ω± ), baryon-to-meson ratios (Λ/ $$ {\textrm{K}}_{\textrm{S}}^0 $$ / $$ {\textrm{K}}_{\textrm{S}}^0 $$ / $$ {\textrm{K}}_{\textrm{S}}^0 $$ / Λ, Ω/ Λ, and Ω/ Ξ) associated with jets and the underlying event were measured as a function of transverse momentum (p T) in pp collisions at$$ \sqrt{s} $$ $$ \sqrt{s_{\textrm{NN}}} $$ . 02 TeV with the ALICE detector at the LHC. The inclusive production of the same particle species and the corresponding ratios are also reported. The production of multi-strange hadrons, Ξ± and Ω± , and their associated particle ratios in jets and in the underlying event are measured for the first time. In both pp and p–Pb collisions, the baryon-to-meson and baryon-to-baryon yield ratios measured in jets differ from the inclusive particle production for low and intermediate hadronp T(0.6–6 GeV/c ). Ratios measured in the underlying event are in turn similar to those measured for inclusive particle production. In pp collisions, the particle production in jets is compared with Pythia 8 predictions with three colour-reconnection implementation modes. None of them fully reproduces the data in the measured hadronp Tregion. The maximum deviation is observed for Ξ± and Ω± which reaches a factor of about six. The event multiplicity dependence is further investigated in p−Pb collisions. In contrast to what is observed in the underlying event, there is no significant event-multiplicity dependence for particle production in jets. The presented measurements provide novel constraints on hadronisation and its Monte Carlo description. In particular, they demonstrate that the fragmentation of jets alone is insufficient to describe the strange and multi-strange particle production in hadronic collisions at LHC energies. -
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A<sc>bstract</sc> We report a new measurement of the production of electrons from open heavy-flavor hadron decays (HFEs) at mid-rapidity (|
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Abstract The azimuthal (
$$\Delta \varphi $$ $$\sqrt{s_{\mathrm{{NN}}}} = 5.02$$ $$4 $$\textrm{GeV}/c$$ $$|\eta |<0.6$$ $$1 $$\textrm{GeV}/c$$ $$|\Delta \eta | < 1$$ $$\Delta \varphi $$ -
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A<sc>bstract</sc> The transverse momentum (
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1007/JHEP08(2023)006
