The $p_{\rm T}$-differential production cross sections of prompt D$^{0}$, $\Lambda_{\rm c}^{+}$, and $\Sigma_{\rm c}^{0,++}(2455)$ charmed hadrons are measured at midrapidity ($|y| < 0.5$) in pp collisions at $\sqrt{s} = 13$ TeV. This is the first measurement of $\Sigma_{\rm c}^{0,++}$ production in hadronic collisions. Assuming the same production yield for the three $\Sigma_{\rm c}^{0,+,++}$ isospin states, the baryon-to-meson cross section ratios $\Sigma_{\rm c}^{0,+,++}/{\rm D}^{0}$ and $\Lambda_{\rm c}^{+}/{\rm D}^{0}$ are calculated in the transverse momentum ($p_{\rm T}$) intervals $2 < p_{\rm T} < 12$ GeV/$c$ and $1 < p_{\rm T} < 24$ GeV/$c$. Values significantly larger than in e$^{+}$e$^{-}$ collisions are observed, indicating for the first time that baryon enhancement in hadronic collisions also extends to the $\Sigma_{\rm c}$. The feed-down contribution to $\Lambda_{\rm c}^{+}$ production from $\Sigma_{\rm c}^{0,+,++}$ is also reported and is found to be larger than in e$^{+}$e$^{-}$ collisions. The data are compared with predictions from event generators and other phenomenological models, providing a sensitive test of the different charm-hadronisation mechanisms implemented in the models.
$p_\mathrm{T}$-differential cross section of prompt $D^0$ in pp collisions at $\sqrt{s}$ = 13 TeV
$p_\mathrm{T}$-differential cross section of prompt $\Lambda_c^+$ in pp collisions at $\sqrt{s}$ = 13 TeV
$p_\mathrm{T}$-differential cross section of prompt $\Sigma_c^{0,++}$ in pp collisions at $\sqrt{s}$ = 13 TeV
The production of $\phi$ mesons has been studied in pp collisions at LHC energies with the ALICE detector via the dimuon decay channel in the rapidity region $2.5 < y < 4$. Measurements of the differential cross section ${\rm d}^2\sigma/{\rm d}y {\rm d}p_{\rm T}$ are presented as a function of the transverse momentum ($p_{\rm T}$) at the center-of-mass energies $\sqrt{s}=5.02$, 8 and 13 TeV and compared with the ALICE results at midrapidity. The differential cross sections at $\sqrt{s}=5.02$ and 13 TeV are also studied in several rapidity intervals as a function of $p_{\rm T}$, and as a function of rapidity in three $p_{\rm T}$ intervals. A hardening of the $p_{\rm T}$-differential cross section with the collision energy is observed, while, for a given energy, $p_{\rm T}$ spectra soften with increasing rapidity and, conversely, rapidity distributions get slightly narrower at increasing $p_{\rm T}$. The new results, complementing the published measurements at $\sqrt{s}=2.76$ and 7 TeV, allow one to establish the energy dependence of $\phi$ meson production and to compare the measured cross sections with phenomenological models. None of the considered models manages to describe the evolution of the cross section with $p_{\rm T}$ and rapidity at all the energies.
$\phi$ meson production cross section $\mathrm{d}^2\sigma/(\mathrm{d}y\mathrm{d}p_\mathrm{T})$ as a function of $p_\mathrm{T}$ at $\sqrt{s}=5.02$ TeV at forward rapidity in pp collisions.
$\phi$ meson production cross section $\mathrm{d}^2\sigma/(\mathrm{d}y\mathrm{d}p_\mathrm{T})$ as a function of $p_\mathrm{T}$ at $\sqrt{s}=8$ TeV at forward rapidity in pp collisions.
$\phi$ meson production cross section $\mathrm{d}^2\sigma/(\mathrm{d}y\mathrm{d}p_\mathrm{T})$ as a function of $p_\mathrm{T}$ at $\sqrt{s}=13$ TeV at forward rapidity in pp collisions.
The ALICE Collaboration has measured inclusive J/psi production in pp collisions at a center of mass energy sqrt(s)=2.76 TeV at the LHC. The results presented in this Letter refer to the rapidity ranges |y|<0.9 and 2.5<y<4 and have been obtained by measuring the electron and muon pair decay channels, respectively. The integrated luminosities for the two channels are L^e_int=1.1 nb^-1 and L^mu_int=19.9 nb^-1, and the corresponding signal statistics are N_J/psi^e+e-=59 +/- 14 and N_J/psi^mu+mu-=1364 +/- 53. We present dsigma_J/psi/dy for the two rapidity regions under study and, for the forward-y range, d^2sigma_J/psi/dydp_t in the transverse momentum domain 0<p_t<8 GeV/c. The results are compared with previously published results at sqrt(s)=7 TeV and with theoretical calculations.
Double differential J/$\psi$ production cross section at $\sqrt{s}=2.76$ TeV. The first uncertainty is statistical, the second one is $p_{\rm T}$-coorelated, the third one is uncorrelated. Polarization-related uncertainties are not included.
The $\sqrt{s}$-dependence of $\langle p_{\rm T}\rangle$ for inclusive J/$\psi$ production (forward rapidity).
the $\sqrt{s}$-dependence of $\langle p_{\rm T}\rangle$ for inclusive J/$\psi$ production (forward rapidity).
The ALICE experiment at the LHC has studied inclusive J/$\psi$ production at central and forward rapidities in pp collisions at $\sqrt{s} = 7$ TeV. In this Letter, we report on the first results obtained detecting the J/$\psi$ through its dilepton decay into $e^+e^-$ and $\mu^+\mu^-$ pairs in the rapidity range |y|<0.9 and 2.5<y<4, respectively, and with acceptance down to zero $p_{\rm T}$. In the dielectron channel the analysis was carried out on a data sample corresponding to an integrated luminosity $L_{\rm int}$ = 5.6 nb$^{-1}$ and the number of signal events is $N_{J/\psi}=352 \pm 32$ (stat.) $\pm$ 28 (syst.); the corresponding figures in the dimuon channel are $L_{\rm int}$ = 15.6 nb$^{-1}$ and $N_{J/\psi} = 1924 \pm 77$ (stat.) $\pm$ 144(syst.). The measured production cross sections are $\sigma_{J/\psi}$ (|y|<0.9) = 12.4 $\pm$ 1.1 (stat.) $\pm$ 1.8 (syst.) + 1.8 -2.7 (syst.pol.) $\mu$b and $\sigma_{J/\psi}$ (2.5<y<4) = 6.31 $\pm$ 0.25 (stat.) $\pm$ 0.76 (syst.) +0.95 -1.96 (syst.pol.) $\mu$b. The differential cross sections, in transverse momentum and rapidity, of the J/$\psi$ were also measured.
Double differential J/PSI cross section from the di-electron channel as a function of transverse momentum, the first error is statistical, the first systematic error is the correlated one, the second is the non-correlated one. The last four columns are the errors considering. a +1 polarization in the Collins-Soper frame, a -1 polarization in the Collins-Soper frame, a +1 polarization in the Helicity frame and a -1 polarization in the Helicity frame, respectively.
Differential J/PSI cross section from the di-muon channel as a function of transverse momentum, the first error is statistical, the first systematic error is the correlated one, the second is the non-correlated one. The last four columns are the errors (in MUB/GEV) considering a +1 polarization in the Collins-Soper frame, a -1 polarization in the Collins-Soper frame, a +1 polarization in the Helicity frame and a -1 polarization in the Helicity frame, respectively.
Differential J/PSI cross section from the di-electron and di-muon channel as a function of rapidity, the first error is statistical, the first systematic error is the correlated one, the second is the non-correlated one. The last four columns are the errors (in MUB/GEV) considering. Data in the first point of this table updated from the erratum.
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