Observation of a multiplicity dependence in the $p_{\rm T}$-differential charm baryon-to-meson ratios in proton-proton collisions at $\sqrt{s} = 13$ TeV

The ALICE collaboration
Phys.Lett.B 829 (2022) 137065, 2022.

Abstract (data abstract)
The production of prompt $\rm D^{0}$, $\rm D^{+}_{s}$, and $\rm \Lambda_{c}^{+}$ hadrons, and their ratios, $\rm D^{+}_{s} / D^{0}$ and $\rm \Lambda_{c}^{+} / D^{0}$, are measured in proton--proton collisions at $\sqrt{s}=13$~TeV at midrapidity ($|y|<0.5$) with the ALICE detector at the LHC. The measurements are performed as a function of the charm-hadron transverse momentum ($p_{\rm T}$) in intervals of charged-particle multiplicity, measured with two multiplicity estimators covering different pseudorapidity regions. While the strange to non-strange $\rm D^{+}_{s} / D^{0}$ ratio indicates no significant multiplicity dependence, the baryon-to-meson $p_{\rm T}$-differential $\rm \Lambda_{c}^{+} / D^{0}$ ratio shows a multiplicity-dependent enhancement, with a significance of 5.3$\sigma$ for $1 < p_{\rm T} < 12$~GeV/$c$, comparing the highest multiplicity interval with respect to the lowest one. The measurements are compared with a theoretical model that explains the multiplicity dependence by a canonical treatment of quantum charges in the statistical hadronisation approach, and with predictions from event generators that implement colour reconnection mechanisms beyond the leading colour approximation to model the hadronisation process. The $\rm \Lambda_{c}^{+} / D^{0}$ ratios as a function of $p_{\rm T}$ present a similar shape and magnitude as the $\rm \Lambda/K^{0}_{S}$ ratios in comparable multiplicity intervals, suggesting a potential common mechanism for light- and charm-hadron formation, with analogous multiplicity dependence. The $p_{\rm T}$-integrated ratios, extrapolated down to $p_{\rm T}=0$, do not show a significant dependence on multiplicity within the uncertainties.

  • Table 1a

    Data from Figure 1, top left panel

    10.17182/hepdata.128718.v1/t1

    Transverse-momentum spectra of $\mathrm{D^0}$ hadrons measured in pp collisions at $\sqrt{{s}} = 13$~TeV for different multiplicity classes selected with the...

  • Table 1b

    Data from Figure 1, top middle panel

    10.17182/hepdata.128718.v1/t2

    Transverse-momentum spectra of $\mathrm{D_s^+}$ hadrons measured in pp collisions at $\sqrt{{s}} = 13$~TeV for different multiplicity classes selected with the...

  • Table 1c

    Data from Figure 1, top right panel

    10.17182/hepdata.128718.v1/t3

    Transverse-momentum spectra of $\mathrm{\Lambda_c^+}$ hadrons measured in pp collisions at $\sqrt{{s}} = 13$~TeV for different multiplicity classes selected with the...

  • Table 1aR

    Data from Figure 1, bottom left panel

    10.17182/hepdata.128718.v1/t4

    Transverse-momentum spectra ratios of $\mathrm{D^0}$ hadrons measured in pp collisions at $\sqrt{{s}} = 13$~TeV for different multiplicity classes selected with...

  • Table 1bR

    Data from Figure 1, bottom middle panel

    10.17182/hepdata.128718.v1/t5

    Transverse-momentum spectra ratios of $\mathrm{D_s^+}$ hadrons measured in pp collisions at $\sqrt{{s}} = 13$~TeV for different multiplicity classes selected with...

  • Table 1cR

    Data from Figure 1, bottom right panel

    10.17182/hepdata.128718.v1/t6

    Transverse-momentum spectra ratios of $\mathrm{\Lambda_c^+}$ hadrons measured in pp collisions at $\sqrt{{s}} = 13$~TeV for different multiplicity classes selected with...

  • Table 2a

    Data from Figure 2, top left panel

    10.17182/hepdata.128718.v1/t7

    The $\mathrm{D_s^+ / D^0}$ ratio measured in pp collisions at $\sqrt{s} = 13$~TeV for different multiplicity classes selected with the...

  • Table 2b

    Data from Figure 2, top right panel

    10.17182/hepdata.128718.v1/t8

    The $\mathrm{D_s^+ / D^0}$ ratio measured in pp collisions at $\sqrt{s} = 13$~TeV for different multiplicity classes selected with the...

  • Table 2c

    Data from Figure 2, bottom left panel

    10.17182/hepdata.128718.v1/t9

    The $\mathrm{\Lambda_c^+ / D^0}$ ratio measured in pp collisions at $\sqrt{s} = 13$~TeV for different multiplicity classes selected with the...

  • Table 2d

    Data from Figure 2, bottom right panel

    10.17182/hepdata.128718.v1/t10

    The $\mathrm{\Lambda_c^+ / D^0}$ ratio measured in pp collisions at $\sqrt{s} = 13$~TeV for different multiplicity classes selected with the...

  • Table 5

    Data from Figure 5

    10.17182/hepdata.128718.v1/t11

    The extrapolated $p_\mathrm{T}$-integrated $\mathrm{\Lambda_c^+ / D^0}$ ratio measured as a function of $\langle \mathrm{d}N_\mathrm{ch}/\mathrm{d}\eta \rangle$ in pp collisions at $\sqrt{{s}}...

  • Table sup3a

    Data from Figure 3 (suppl. material), top left panel

    10.17182/hepdata.128718.v1/t12

    Transverse-momentum spectra of $\mathrm{D^0}$ hadrons measured in pp collisions at $\sqrt{{s}} = 13$~TeV for different multiplicity classes selected with the...

  • Table sup3b

    Data from Figure 3 (suppl. material), top middle panel

    10.17182/hepdata.128718.v1/t13

    Transverse-momentum spectra of $\mathrm{D_s^+}$ hadrons measured in pp collisions at $\sqrt{{s}} = 13$~TeV for different multiplicity classes selected with the...

  • Table sup3c

    Data from Figure 3 (suppl. material), top right panel

    10.17182/hepdata.128718.v1/t14

    Transverse-momentum spectra of $\mathrm{\Lambda_c^+}$ hadrons measured in pp collisions at $\sqrt{{s}} = 13$~TeV for different multiplicity classes selected with the...

  • Table sup3aR

    Data from Figure 3 (suppl. material), bottom left panel

    10.17182/hepdata.128718.v1/t15

    Transverse-momentum spectra ratios of $\mathrm{D^0}$ hadrons measured in pp collisions at $\sqrt{{s}} = 13$~TeV for different multiplicity classes selected with...

  • Table sup3bR

    Data from Figure 3 (suppl. material), bottom middle panel

    10.17182/hepdata.128718.v1/t16

    Transverse-momentum spectra ratios of $\mathrm{D_s^+}$ hadrons measured in pp collisions at $\sqrt{{s}} = 13$~TeV for different multiplicity classes selected with...

  • Table sup3cR

    Data from Figure 3 (suppl. material), bottom right panel

    10.17182/hepdata.128718.v1/t17

    Transverse-momentum spectra ratios of $\mathrm{\Lambda_c^+}$ hadrons measured in pp collisions at $\sqrt{{s}} = 13$~TeV for different multiplicity classes selected with...

  • Table sup6a

    Data from Figure 6 (suppl. material), left panel

    10.17182/hepdata.128718.v1/t18

    The visible $p_\mathrm{T}$-integrated $\mathrm{D_s^+ / D^0}$ ratio measured as a function of $\langle \mathrm{d}N_\mathrm{ch}/\mathrm{d}\eta \rangle$ in pp collisions at $\sqrt{{s}}...

  • Table sup6b

    Data from Figure 6 (suppl. material), right panel

    10.17182/hepdata.128718.v1/t19

    The visible $p_\mathrm{T}$-integrated $\mathrm{\Lambda_c^+ / D^0}$ ratio measured as a function of $\langle \mathrm{d}N_\mathrm{ch}/\mathrm{d}\eta \rangle$ in pp collisions at $\sqrt{{s}}...

  • Table sup7

    Data from Figure 7 (suppl. material), bottom left panel

    10.17182/hepdata.128718.v1/t20

    The extrapolated $p_\mathrm{T}$-integrated $\mathrm{D_s^+ / D^0}$ ratio measured as a function of $\langle \mathrm{d}N_\mathrm{ch}/\mathrm{d}\eta \rangle$ in pp collisions at $\sqrt{{s}}...

Loading Data...

Ask a Question


Your question will be emailed to those involved with the submission. Please mention the relevant table.


Please log in to HEPData to send a question.