Origin of the Proton Mass

The National Academies of Sciences, Engineering, and Medicine (NAS) identified three high-priority science questions to understand the hadron structure in their report “An Assessment of U.S.-Based Electron-Ion Collider Science”. The first of the three questions is “How does the mass of the nucleon arise?”. Our group is spearheading an experimental program that aims to decode the mass-budget of the nucleon.

The Solenoidal Large Intensity Device (SoLID), is a long-term and large-scale project that will carry the future experimental program in Hall A at Jefferson Lab. The SoLID physics program involves three parallel scientific pillars. Our group is holding a leading role in one of these programs. Prof. Sparveris is a co-spokesperson of the SoLID-J/Psi experiment, that will study in depth a number of key aspects of nucleon’s low energy structure, and will measure with high precision an important component of the proton mass budget, the trace anomaly.

Figure: The Solenoidal Large Intensity Device (SoLID). The Temple group has a responsibility towards the construction of the SoLID Light Gas Cherenkov (LGC), shown at the center. A blown-out view of one of the LGC sectors is shown at the right panel.