CERN Accelerating science

1) Starting situation after the number of protons (red) and neutrons (blue) have been determined. 2) For each proton, a new set of neutrons is generated. 3) One proton-neutron pair that satisfies the coalescence condition forms a deuteron. 4) Next proton of the event gets a new set of neutrons. The amount of neutrons has been reduced by one since one neutron was bound to a proton to form the deuteron.

An example of the fragmentation of a $\texttt{d}\Bar{\texttt{d}}$ string. Mesons are indicated for clarity but are ignored for coalescence in ToMCCA.

Scaling of the baryon-emitting source size as a function of $\langle m_T\rangle$, for arbitrary multiplicity values. The predictions of ToMCCA are compared to the measured source size corresponding to an event multiplicity of about 30~\cite{sourceSizeHMpp}.

Results of ToMCCA in different multiplicity classes, for the transverse momentum spectra of protons (top left) and deuterons (top right), and the coalescence parameter $B_2$ (bottom), compared to data measured by ALICE. The values of the average charged-particle multiplicity corresponding to each multiplicity class in the three different collision energies are indicated in the legend. The values of $B_2$ are scaled for better visibility, by the following factors, going from the top to the bottom: 42, 16, 8, 4, 2, 1.

Results of ToMCCA in the multiplicity class VI, VII and VI+VII respectively for pp $\sqrt{s} =$ 5, 13 and 7 TeV, for the transverse momentum spectra of protons (top left) and deuterons (top right), and the coalescence parameter $B_2$ (bottom), compared to data measured by ALICE. The values of the average charged-particle multiplicity corresponding to each multiplicity class (VI, VII, and VI+VII) in the three different collision energies are indicated in the legend.

Coalescence parameter $B_2$ as a function of multiplicity predicted by ToMCCA (red line), compared with the $B_2$ measurements from ALICE. The blue markers show the data included in the parametrizations, while the green markers show the ones not included. The dotted line is the model prediction of Ref.~\cite{Bellini:2018epz}, where the coalescence parameter for deuterons with a size of 3.2~fm is computed.

Deuteron-to-proton ratio of integrated yields as a function of multiplicity obtained with ToMCCA (red solid line), compared to measurements of the ALICE Collaboration. The width of the model predictions reflects the statistical uncertainties. The dotted line is the model prediction of Ref.~\cite{Coalescence6}.

Correlation coefficient for antiprotons and antideuterons ($\rho_{\overline{\rm p}\overline{\rm d}}$) as a function of the cubic root of the charged-particle multiplicity, predicted by ToMCCA, with the three different hadronization models, compared to the ALICE measurements in Pb--Pb collisions~\cite{FluctuationsPbPb}.