Meson Structure From Basis Light Front Quantization

Basis Light-Front Quantization（BLFQ）has been constructed as a non-perturbative approach to bound state problems in the light-front Hamiltonian framework.In this work,we apply BLFQ to light mesons,strange mesons as well as strangeonia and study their mass spectrum and structure.We ob-tain the light-front wave functions（LFWFs）of mesons by solving the eigen-equation of a model Hamiltonian.Our basis includes|q（?）iand|q（?）giFock s-paces.The model Hamiltonian contains the kinetic energy of partons,an effec-tive 3-dimensional confining potential,the quark-gluon vectex interaction and the instantaneous gluon exchange interaction based on quantum chromodynam-ics（QCD）.The model parameters are determined by matching the light meson mass spectroscopy with the experimental data.The obtained LFWF of the pio-n provides decent descriptions of the decay constant（DC）,the electromagnetic form factor（EMFF）,the transition form factor（TFF）,and the parton distribution amplitude（PDA）.The parton distribution function（PDF）of the valence quark in the pion,after QCD evolution,agrees with the PDF extracted from the exper-imental result.We further obtain the differential cross sections for the dilepton production and J/production in pion-nucleus collisions,which are consistent with various experimental data.We also present the generalized parton distri-butions（GPDs）and the transverse-momentum-dependent parton distributions（TMDs）of the pion.In addition,we study the mass spectrum and structure of the strange meson-s and strangeonia.We assume that the strange meson and strangeonium sys-tems share the same set of model parameters as the light mesons except that the mass of the strange quark takes a value different from that of the light quark.After determining the mass of strange quark by matching the mass spec-troscopy of（1020）,and（1680）,and ₃（1850）with experimental data,we obtain a good description of the strangeonia mass spectrum including（1020）,f₀（1370）,f₂（1525）,（1680）and ₃（1850）mesons,as well as the strange mesons mass spectroscopy including K^*,K₁（1400）,K^*（1410）,K^*₂（1430）and K±（1460）mesons.From the obtained LFWFs,we calculate the DC,EMFF,PDA,and PDF of the strange mesons and strangeonia.The obtained DC of the meson is only 23%less than the experimental result.The obtained DC of the kaon is 166.9 Me V,which is only 7%large than the experimental result of 155.6（4）Me V.The obtained EMFF of the kaon decently agrees with the experimental data from CERN SPS and Fermilab.The kaon PDF reasonably agrees with the NA3 experimental result.We further predict the differential cross sections for the dilepton production and J/production in kaon-nucleus collisions,which will be measured over the next few years by the COMPASS++/AMBER Col-laboration.Finally,we also present the GPDs and the TMDs of the meson and the kaon.