Nuclear physicists have been trying to uncover how the proton gets its spin, and a new method combining experimental data with calculations has shed light on the gluons’ contributions to this spin. Led by Joseph Karpie, the work revealed that the proton’s quarks only provide 30% of its total spin, while the remaining comes from the strong force and the movements of the proton’s quarks and gluons. This study was inspired by experimental measurements showing conflicting results regarding the spins of gluons aligning with the proton’s spin.
Both the Jefferson Lab Angular Momentum (JAM) collaboration and the HadStruc collaboration tackled the measurements in different ways, with the latter using supercomputers to calculate the Quantum Chromodynamics (QCD) that describes the interactions among quarks and gluons. To analyze the data, theorists simplify the theory into lattice QCD for supercomputers. Karpie combined the experimental data with the lattice QCD results to provide a more detailed understanding of the quark and gluon spin contributions to the proton’s spin.
Through the combined analysis, it was observed that the negative results indicated a potential peculiarity with the gluons’ spin contributions. With the improved accuracy of the analysis, it led to a better-informed result by combining both datasets. This integration of experimental data and theoretical calculations demonstrated the effectiveness of this approach in advancing the understanding of the proton’s structure. The main takeaway was that combining both approaches yielded a more significant result than individual analyses, highlighting the importance of collaboration in enhancing knowledge.
The next step is to enhance the datasets further as more sophisticated experiments provide detailed information about the proton. By improving calculations on powerful supercomputers, scientists aim to develop a three-dimensional understanding of the proton’s structure. The goal is to progress towards a comprehensive 3D image of the proton’s structure, allowing for a deeper exploration into the heart of the problem. This work sets the foundation for future studies that will contribute to advancing the current understanding of the proton’s structure and its fundamental components.
Overall, the study provides valuable insights into the spin contributions from quarks and gluons in the proton, laying the groundwork for future research. By combining experimental data with theoretical calculations, scientists can gain a more comprehensive understanding of the proton’s structure and its spin. The collaborative effort between experimentalists and theorists has proven to be a successful approach in advancing the field of nuclear physics. Through continued research and technological advancements, scientists aim to unveil a detailed 3D representation of the proton’s structure, offering further insights into the fundamental particles that make up the universe.