“Hadronic molecules” (2018), by Feng-Kun Guo et al. Physics and Astronomy research paper. Original abstract below, unchanged. A free PDF is available.

Hadronic molecules

Feng-Kun Guo, C. Hanhart, Ulf-G. Meißner et al. · February 8, 2018 · Physics and Astronomy

Abstract

Hadrons are composite particles made of quark and gluons. Interestingly, some excited hadronic states resemble the deuteron viewed as a barely bound neutron-proton system. Such hadronic molecules are spatially extended systems lying very close to decay thresholds. This work reviews the current experimental evidence for hadronic molecules and related theoretical descriptions, including effective field theories and lattice quantum chromodynamics.

Free PDF DOI: 10.1103/revmodphys.90.015004