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Mid-rapidity anti-baryon to baryon ratios in pp collisions at $$\sqrt{s} = 0.9,\ 2.76\mbox{ and }7\mbox{ TeV}$$ measured by ALICE

Journal Article · · European Physical Journal. C, Particles and Fields
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The ratios of yields of anti-baryons to baryons probes the mechanisms of baryon-number transport. Results for \(\overline{\mathrm {p}}/{\mathrm{p}}\), \(\overline{\Lambda}/{\Lambda}\), \({{\overline{\Xi}}^{+}}/{\Xi ^{-}}\) and \({{\overline{\Omega}}^{+}}/{\Omega^{-}}\) in pp collisions at \(\sqrt{s} = 0.9,\ 2.76\mbox{ and }7\mbox{ TeV}\), measured with the ALICE detector at the LHC, are reported. Within the experimental uncertainties and ranges covered by our measurement, these ratios are independent of rapidity, transverse momentum and multiplicity for all measured energies. The results are compared to expectations from event generators, such as PYTHIA and HIJING/B, that are used to model the particle production in pp collisions. The energy dependence of \(\overline{\mathrm{p}}/{\mathrm{p}}\), \(\overline {\Lambda}/{\Lambda}\), \({{\overline{\Xi}}^{+}}/{\Xi^{-}}\) and \({{\overline{\Omega}}^{+}}/{\Omega^{-}}\), reaching values compatible with unity for \(\sqrt{s} = 7\mbox{ TeV}\), complement the earlier \(\overline{\mathrm{p}}/{\mathrm{p}}\) measurement of ALICE. These dependencies can be described by exchanges with the Regge-trajectory intercept of \(\alpha_{\rm{J}} \approx0.5\), which are suppressed with increasing rapidity interval Δy. Any significant contribution of an exchange not suppressed at large Δy (reached at LHC energies) is disfavoured.
Research Organization:
Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
Sponsoring Organization:
USDOE; National Science Foundation (NSF); State of Texas; State of Ohio
Contributing Organization:
The ALICE Collaboration
Grant/Contract Number:
AC05-00OR22725
OSTI ID:
1135872
Alternate ID(s):
OSTI ID: 22138879
Journal Information:
European Physical Journal. C, Particles and Fields, Journal Name: European Physical Journal. C, Particles and Fields Journal Issue: 7 Vol. 73; ISSN 1434-6044
Publisher:
SpringerCopyright Statement
Country of Publication:
United States
Language:
English

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Cited By (13)

Cosmic ray antiprotons at high energies journal February 2017
Magnetohydrodynamics, charged currents, and directed flow in heavy ion collisions journal May 2014
Production of light nuclei and anti-nuclei in p p and Pb-Pb collisions at energies available at the CERN Large Hadron Collider journal February 2016
Freeze-out conditions in proton-proton collisions at the highest energies available at the BNL Relativistic Heavy Ion Collider and the CERN Large Hadron Collider journal January 2017
Production of deuterons, tritons, He 3 nuclei, and their antinuclei in p p collisions at s = 0.9 , 2.76, and 7 TeV journal February 2018
p − p ,   p − Λ , and Λ − Λ correlations studied via femtoscopy in p p reactions at s = 7 TeV journal February 2019
Multiplicity dependence of light-flavor hadron production in p p collisions at s = 7 TeV journal February 2019
Measurement of the forward-backward asymmetry of Λ and Λ ¯ production in p p ¯ collisions journal February 2016
Production of $$\mathbf {\Sigma (1385)^{\pm }}$$ Σ ( 1385 ) ± and $$\mathbf {\Xi (1530)^{0}}$$ Ξ ( 1530 ) 0 in proton–proton collisions at $$\mathbf {\sqrt{s}=}$$ s = 7 TeV journal January 2015
Equilibrium statistical–thermal models in high-energy physics journal June 2014
Particle Transverse Momentum Distributions in p-p Collisions at √ s N N = 0.9 TeV journal April 2019
Equilibrium Statistical-Thermal Models in High-Energy Physics text January 2014
Cosmic Ray Antiprotons at High Energies text January 2017


Figures / Tables (32)


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