mi mi

quark model

wave function

bar bar

Reviews of Modern Physics

A large number of experimental discoveries especially in the heavy quarkonium\nsector that did not at all fit to the expectations of the until then very\nsuccessful quark model led to a renaissance of hadron spectroscopy. Among\nvarious explanations of the internal structure of these excitations, hadronic\nmolecules, being analogues of light nuclei, play a unique role since for those\npredictions can be made with controlled uncertainty. We review experimental\nevidences of various candidates of hadronic molecules, and methods of\nidentifying such structures. Nonrelativistic effective field theories are the\nsuitable framework for studying hadronic molecules, and are discussed in both\nthe continuum and finite volumes. Also pertinent lattice QCD results are\npresented. Further, we discuss the production mechanisms and decays of hadronic\nmolecules, and comment on the reliability of certain assertions often made in\nthe literature.\n

Hadronic molecules