Электронный каталог

Статья

Acharya, S.
Light Neutral-Meson Production in pp Collisions at *%s=13 TeV / S.Acharya, B.Batyunya, R.A.Diaz, S.Grigoryan, A.Kondratyev, A.Kuznetsov, L.Malinina, K.Mikhaylov, P.Nomokonov, V.Pozdniakov, E.Rogochaya, A.Vodopyanov, [ALICE Collab.]. – Text : electronic // Journal of High Energy Physics. – 2025. – Vol. 2025, No. 8. – P. 035. – URL: https://doi.org/10.1007/JHEP08(2025)035. – Bibliogr.: 91.

The momentum-diferential invariant cross sections of π*0 and η mesons are reported for pp collisions at √ s = 13 TeV at midrapidity (|y| < 0.8). The measurement is performed in a broad transverse-momentum range of 0.2 < p&sub(T) < 200 GeV/c and 0.4 < p&sub(T) < 60 GeV/c for the π*0 and η, respectively, extending the pT coverage of previous measurements. Transverse-mass-scaling violation of up to 60% at low transverse momentum has been observed, agreeing with measurements at lower collision energies. Transverse Bjorken x (x&su(T)) scaling of the π*0 cross sections at LHC energies is fulfilled with a power-law exponent of n = 5.01±0.05, consistent with values obtained for charged pions at similar collision energies. The data are compared to predictions from next-to-leading order perturbative QCD calculations, where the π*0 spectrum is best described using the CT18 parton distribution function and the NNFF1.0 or BDSS fragmentation function. Expectations from PYTHIA8 and EPOS LHC overestimate the spectrum for the π*0 and are not able to describe the shape and magnitude of the η spectrum. The charged-particle multiplicity dependent π*0 and η p&sub(T) spectra show the expected change of the spectral shape, characterized by a fatter slope with increasing multiplicity. This is demonstrated across a broad transverse-momentum range and up to events with a charged-particle multiplicity exceeding fve times the mean value in minimum bias collisions. The η/π*0 ratio depends on the charged-particle multiplicity for p&sub(T) < 4 GeV/c. PYTHIA8 and EPOS LHC qualitatively explain this behavior with an increasing contribution from the feed-down of heavier particles to the π 0 spectrum.



ОИЯИ = ОИЯИ (JINR)2025