Hadronic molecules with heavy meson loops (B03)

• Subject Area: Nuclear and Elementary Particle Physics, Quantum Mechanics, Relativity, Fields
• Term: from 2012 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 196253076

Since 2003, when the discovery of the X(3872) started a new era of hadron spectroscopy, many socalled exotic states were found experimentally that show properties grossly at odds with those predicted by the until then extremely successful quark model, which worked especially well in the heavy quark sector. Most of these are located close to a threshold of two narrow hadrons. This suggests that these states might be hadronic molecules — bound states of the mentioned hadron pair similar to atomic nuclei being made of protons and neutrons. The main goal of this project is to systematically map out the implications of the hypothesis that most of those exotic states are predominantly of a molecular nature. In the third funding period we plan to work on a consistent picture for molecule candidates and threshold phenomena simultaneously. This implies a significant extension of the methods used previously, extending our investigations to the pentaquarks observed by LHCb.

• DFG Programme: CRC/Transregios
• Subproject of: TRR 110: Symmetries and the Emergence of Structure in Quantum Chromodynamics (QCD)
• International Connection: China
• Applicant Institution: Rheinische Friedrich-Wilhelms-Universität Bonn
• Project Heads: Professor Dr. Feng-Kun Guo, until 6/2016; Professor Dr. Christoph Hanhart; Professorin Dr. Qian Wang, since 7/2016; Professor Dr. Qiang Zhao