Deeply virtual Compton scattering off the neutron
Abstract
The three-dimensional structure of nucleons (protons and neutrons) is embedded in so-called generalized parton distributions, which are accessible from deeply virtual Compton scattering. In this process, a high energy electron is scattered off a nucleon by exchanging a virtual photon. Then, a highly-energetic real photon is emitted from one of the quarks inside the nucleon, which carries information on the quark's transverse position and longitudinal momentum. By measuring the cross-section of deeply virtual Compton scattering, Compton form factors related to the generalized parton distributions can be extracted. Here, we report the observation of unpolarized deeply virtual Compton scattering off a deuterium target. From the measured photon-electroproduction cross-sections, we have extracted the cross-section of a quasi-free neutron and a coherent deuteron. Due to the approximate isospin symmetry of quantum chromodynamics, we can determine the contributions from the different quark flavours to the helicity-conserved Compton form factors by combining our measurements with previous ones probing the proton's internal structure. These results advance our understanding of the description of the nucleon structure, which is important to solve the proton spin puzzle.
Cite
@article{arxiv.2109.02076,
title = {Deeply virtual Compton scattering off the neutron},
author = {M. Benali and C. Desnault and M. Mazouz and Z. Ahmed and H. Albataineh and K. Allada and K. A. Aniol and V. Bellini and W. Boeglin and P. Bertin and M. Brossard and A. Camsonne and M. Canan and S. Chandavar and C. Chen and J. -P. Chen and M. Defurne and C. W. de Jager and R. de Leo and A. Deur and L. El Fassi and R. Ent and D. Flay and M. Friend and E. Fuchey and S. Frullani and F. Garibaldi and D. Gaskell and A. Giusa and O. Glamazdin and S. Golge and J. Gomez and O. Hansen and D. Higinbotham and T. Holmstrom and T. Horn and J. Huang and M. Huang and G. M. Huber and C. E. Hyde and S. Iqbal and F. Itard and Ho. Kang and Hy. Kang and A. Kelleher and C. Keppel and S. Koirala and I. Korover and J. J. LeRose and R. Lindgren and E. Long and M. Magne and J. Mammei and D. J. Margaziotis and P. Markowitz and A. Marti Jimenez-Arguello and F. Meddi and D. Meekins and R. Michaels and M. Mihovilovic and N. Muangma and C. Munoz Camacho and P. Nadel-Turonski and N. Nuruzzaman and R. Paremuzyan and R. Pomatsalyuk and A. Puckett and V. Punjabi and Y. Qiang and A. Rakhman and M. N. H. Rashad and S. Riordan and J. Roche and G. Russo and F. Sabatie and K. Saenboonruang and A. Saha and B. Sawatzky and L. Selvy and A. Shahinyan and S. Sirca and P. Solvignon and M. L. Sperduto and R. Subedi and V. Sulkosky and C. Sutera and W. A. Tobias and G. M. Urciuoli and D. Wang and B. Wojtsekhowski and H. Yao and Z. Ye and L. Zana and X. Zhan and J. Zhang and B. Zhao and Z. Zhao and X. Zheng and P. Zhu},
journal= {arXiv preprint arXiv:2109.02076},
year = {2021}
}