On the light-front wave functions of quarkonia

The light-front wave functions of hadrons allow us to calculate a wide range of physical observables; however, the wave functions themselves cannot be measured. We discuss recent results for quarkonia obtained in basis light-front quantization using an effective Hamiltonian with a confining model in both the transverse and longitudinal directions and with explicit one-gluon exchange. In particular, we focus on the numerical convergence of the basis expansion, as well as the asymptotic behavior of the light-front wave functions. We also illustrate that, for mesons with unequal quark masses, the maxima of the light-front wave functions depend in a non-trivial way on the valence quark-mass difference.
Comment: to appear in the proceedings of Light Cone 2019 - QCD on the light cone: from hadrons to heavy ions - LC2019, 16-20 September 2019, Ecole Polytechnique, Palaiseau, France