Production of deuterons, tritons, He 3 nuclei, and their antinuclei in pp collisions at s =0.9, 2.76, and 7 TeV

Abstract

Invariant differential yields of deuterons and antideuterons in $pp$ collisions at $\sqrt{s}$ = 0.9, 2.76 and 7 TeV and the yields of tritons, $^{3}\mathrm{He}$ nuclei, and their antinuclei at $\sqrt{s}$ = 7 TeV have been measured with the ALICE detector at the CERN Large Hadron Collider. The measurements cover a wide transverse momentum (${p}_{\text{T}}$) range in the rapidity interval $|y|<0.5$, extending both the energy and the ${p}_{\text{T}}$ reach of previous measurements up to 3 GeV/$c$ for $A=2$ and 6 GeV/$c$ for $A=3$. The coalescence parameters of (anti)deuterons and $^{3}\overline{\text{He}}$ nuclei exhibit an increasing trend with ${p}_{\text{T}}$ and are found to be compatible with measurements in $pA$ collisions at low ${p}_{\text{T}}$ and lower energies. The integrated yields decrease by a factor of about 1000 for each increase of the mass number with one (anti)nucleon. Furthermore, the deuteron-to-proton ratio is reported as a function of the average charged particle multiplicity at different center-of-mass energies.