Measurements of groomed heavy-flavour jet substructure with ALICE

We report the first measurements of the groomed heavy-flavour jet substructure variables z(g), R-g, and n(SD) using the Soft Drop algorithm for charged-particle jets tagged by fully reconstructed D0 mesons in pp collisions at root s = 13 TeV. Iterative declustering techniques access the jet splitting tree of track-based jets, with grooming techniques isolating the perturbative branches. D-0-tagged jets give access to an enriched quark-initiated sample of jets down to low jet transverse momenta (p(T)(jet) (ch)). This provides a new opportunity to explore the differences between quark and gluon fragmentations in vacuum in the region of phase space where the inclusive-jet sample is dominated by gluon-initiated jets and where the mass effects of heavy-flavour quarks are also expected to be the strongest [1]. The shared momentum fraction of the first splitting accepted by the grooming procedure, z(g), and the aperture angle between the prongs of that splitting, R-g, fully corrected to particle level, are presented. The grooming is performed using the iterative Soft Drop [2] technique with parameters z(cut) = 0. 1 and beta = 0. In addition, the number of splittings per jet satisfying the grooming condition, n(sD), is also reported. The results are presented in the 15 <= p(T)(jet) (ch) < 30 GeV/c range and are compared to complementary measurements of inclusive jets as well as to theoretical models. These results also provide a reference for future D-0-tagged jet substructure measurements in heavy-ion collisions, to explore the different energy loss of gluon, light-quark, and heavy-quark jets in the presence of a deconfined QCD medium.