Investigating charm production and fragmentation via azimuthal correlations of prompt D mesons with charged particles in pp collisions at $\sqrt{s}=13$ TeV

Abstract

Angular correlations of heavy-flavour and charged particles in high-energy proton-proton collisions are sensitive to the production mechanisms of heavy quarks and to their fragmentation as well as hadronisation processes. The measurement of the azimuthal-correlation function of prompt D mesons with charged particles in proton-proton collisions at a centre-of-mass energy of $\sqrt{s}=13$ TeV with the ALICE detector is reported, considering D${}^0$, D${}^{+}$, and D${}^{\ast +}$ mesons in the transverse-momentum interval $3<p_{\mathrm{T}}<36$ GeV/$c$ at midrapidity ($|y|<0.5$), and charged particles with $p_{\mathrm{T}}>0.3$ GeV/$c$ and pseudorapidity $|\eta |<0.8$. This measurement has an improved precision and provides an extended transverse-momentum coverage compared to previous ALICE measurements at lower energies. The study is also performed as a function of the charged-particle multiplicity, showing no modifications of the correlation function with multiplicity within uncertainties. The properties and the transverse-momentum evolution of the near- and away-side correlation peaks are studied and compared with predictions from various Monte Carlo event generators. Among those considered, PYTHIA8 and POWHEG+PYTHIA8 provide the best description of the measured observables. The obtained results can provide guidance on tuning the generators.

33 pages, 11 captioned figures, 2 tables, authors from page 28, published version, figures at http://alice-publications.web.cern.ch/node/7447

References in corpus (4)

• Herwig++ Physics and Manual
• Interleaved Parton Showers and Tuning Prospects
• Multiplicity dependence of $\pi$, K, and p production in pp collisions at $\sqrt{s}=13$ TeV
• Studies of charm and beauty hadron long-range correlations in pp and pPb collisions at LHC energies