Fully charmed tetraquarks from LHC to FCC: natural stability from fragmentation

Abstract

We investigate the inclusive production of fully charmed tetraquarks, $$T_{4c}(0^{++})$$ T 4 c ( 0 + + ) or $$T_{4c}(2^{++})$$ T 4 c ( 2 + + ) radial excitations, in high-energy proton collisions. We build our study upon the collinear fragmentation of a single parton in a variable-flavor number scheme, suited to describe the tetraquark formation mechanism from moderate to large transverse-momentum regimes. To this extent, we derive a novel set of DGLAP-evolving collinear fragmentation functions, named determinations. They encode initial-scale inputs corresponding to both gluon and heavy-quark fragmentation channels, defined within the context of quark-potential and spin-physics inspired models, respectively. We work within the NLL/$$\hbox {NLO}^+$$ NLO + hybrid factorization and make use of the numeric interface along with the symbolic calculation plugin. With these tools, we provide predictions for high-energy observables sensitive to $$T_{4c}$$ T 4 c plus jet emissions at center-of-mass energies ranging from 14 TeV at the LHC to the 100 TeV nominal energy of the FCC.