Light (anti)nuclei production at the LHC measured in pp collisions at 13 TeV

Michael Karim Habib
ALICE (A Large Ion Collider Experiment) collected over two billion proton-proton collision events at a center-of-mass energy of 13 TeV during the second running period (from 2016 to 2018) of the Large Hadron Collider (LHC). This rich data sample allows for studies of at this collision energy rarely produced objects, such as light nuclei. In this work, the first multiplicity and transverse-momentum (pT) differential measurement of helium (3He) nuclei and triton (3H) as well as their
more » ... antinuclei in proton-proton collisions at the LHC is presented. The interaction of quarks and gluons, the constituents of all hadrons, is described by quantum chromodynamics (QCD), the theory of the strong interaction. Thus, QCD is the underlying theory of the formation process of light nuclei. In practice, the light nuclei formation in collisions at relativistic energies is modeled using two phenomenological approaches: the statistical hadronization model and the coalescence model. The first expresses the production of all hadrons according to the laws of statistical physics, assuming emission from a medium in local thermal equilibrium. In this approach, the hadron yields are determined by the hadron mass, the chemical freeze-out temperature, the baryon chemical potential, and the system volume. The statistical hadronization model successfully describes the hadron yields over a wide mass range, going from the lowest (a few GeV) to the highest (a few TeV) center-of-mass collision energies. It is effectively applied to small and large systems ranging from e+e− to central uranium-uranium collision. The coalescence model, on the other hand, describes the production mechanism of nuclei on the microscopic level. In the simplest version, a nucleus is formed when its constituent nucleons are close in phase space (momentum and spatial distance are small). More sophisticated versions of the coalescence model take the emission source size and the nuclear radius into account. The key parameter of the model is the coalescence paramet [...]
doi:10.26083/tuprints-00020241 fatcat:tnycj3c5jbaqhk2gu2viurirxa