Measurement of $${{\mathrm{D}}^0}$$, $${{\mathrm{D}}^+}$$, $${{\mathrm{D}}^{*+}}$$ and $${{\mathrm{D}}^+_{\mathrm{s}}}$$ production in pp collisions at $${\sqrt{{\textit{s}}}~=~5.02~{\text {TeV}}}$$ with ALICE

Abstract

The measurements of the production of prompt D 0 , D + , D * + , and D + s mesons in proton-proton (pp) collisions at √ s = 5.02 TeV with the ALICE detector at the Large Hadron Collider (LHC) are reported. D mesons were reconstructed at mid-rapidity (|y| < 0.5) via their hadronic decay channels

Measurement of prompt D0, D+, D*+, and $$ {\mathrm{D}}_{\mathrm{S}}^{+} $$ production in p–Pb collisions at $$ \sqrt{{\mathrm{s}}_{\mathrm{NN}}} $$ = 5.02 TeV

“…The shape of the generated D-meson p T distribution is consistent with that of FONLL pQCD calculations [1] at √ s = 5.02 TeV. The results from FONLL calculations are found to be consistent with pp data at √ s = 5.02 TeV though at upper edge of uncertainties as described in [70]. Figure 2 shows the product of acceptance and efficiency (Acc × ε) for prompt and feeddown D mesons with rapidity |y lab | < y fid (p T ).…”

“…The pp reference for the R pPb and Q pPb calculation was taken from the measurements performed on a data sample of about 990 million minimum-bias pp collisions (L int = (19.3 ± 0.4) nb −1 ) at √ s = 5.02 TeV collected with ALICE in 2017, and published in ref. [70].…”

“…The analysis without decay-vertex reconstruction allows for a direct measurement of the inclusive D 0 -meson cross section because no selections that alter the fraction of prompt and feed-down D mesons are applied. The inclusive D 0 -meson cross section in p-Pb collisions is shown in the left panel of figure 6 and is compared with the measurement in pp collisions at the same centre-of-mass energy, published in [70]. The cross section in pp collisions was scaled by the Pb mass number A = 208 and corrected for the rapidity shift in p-Pb collisions using FONLL calculations.…”

Global Characteristics of the Medium Produced in Ultra-High Energy Cosmic Ray Collisions

“…where s 0 = 1 GeV 2 , ξ ≡ 0.5 N part , N part is the average number of participants and N part = 2 for p + p collisions, free parameters are a 1 = 0.75 ± 0.06, a 2 = 0.114 ± 0.003 for nonsingle diffractive p + p collisions at √ s pp > 20 GeV [3], a 1 = 1.94 ± 0.08, a 2 = 0.103 ± 0.002 for p(d) + A interactions [4] and a 1 = 2.70 ± 0.07, a 2 = 0.155 ± 0.004 for 0-5% most central A + A collisions [5,6]. The total multiplicity of charged particles produced in nuclear collisions depends on s can be approximated by the power function…”

Charmed meson and baryon measurements in pp and p–Pb collisions with ALICE at the LHC

“…GM-VFNS underpredicts the data by a factor of 2.5 on average, and powheg underpredicts the data by a factor of 18(4) at low(high) p T in pp collisions, and by a similar amount in p-Pb collisions. Figure 3 (left) shows the baryon-to-meson ratio Λ + c /D 0 measured using the Λ + c cross sections presented in this paper and the D 0 cross sections measured by ALICE [4,10]. In the same figure theoretical predictions in pp collisions are shown including pythia8 with and without a tune including enhanced colour reconnection [11], dipsy [12] with rope hadronisation and herwig7 [13] with hadronisation via clusters.…”