Nuclear Dependence of Beam Normal Single Spin Asymmetry in Elastic Scattering from Nuclei

Ciprian Gal; Chandan Ghosh; Sanghwa Park; Devi Adhikari; David Armstrong; Rakitha Beminiwattha; Alexandre Camsonne; Shashini Chandrasena; Mark Dalton; Abhay Deshpande; Dave Gaskell; Douglas Higinbotham; Charles J. Horowitz; Paul King; Krishna Kumar; Tyler Kutz; Juliette Mammei; Dustin McNulty; Robert Michaels; Caryn Palatchi; Anil Panta; Kent Paschke; Mark Pitt; Arindam Sen; Neven Simicevic; Lasitha Weliyanga; Steven P. Wells

arXiv · 2411.10267

Nuclear Dependence of Beam Normal Single Spin Asymmetry in Elastic Scattering from Nuclei

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Abstract

We propose to measure the beam normal single spin asymmetry in elastic scattering of transversely polarized electron from target nuclei with 12 $\leq Z \leq$ 90 at Q$^2$ = 0.0092 GeV$^2$ to study its nuclear dependence. While the theoretical calculations based on two-photon exchange suggest no nuclear dependence at this kinematics, the results of 208Pb from Jefferson Lab show a striking disagreement from both theoretical predictions and light nuclei measurements. The proposed measurements will provide new data for intermediate to heavy nuclei where no data exists for $Z \geq$ 20 in the kinematics of previous high-energy experiments. It will allow one to investigate the missing contributions that are not accounted in the current theoretical models.

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Ciprian Gal, Chandan Ghosh, Sanghwa Park, Devi Adhikari, David Armstrong, Rakitha Beminiwattha, Alexandre Camsonne, Shashini Chandrasena, Mark Dalton, Abhay Deshpande, Dave Gaskell, Douglas Higinbotham, Charles J. Horowitz, Paul King, Krishna Kumar, Tyler Kutz, Juliette Mammei, Dustin McNulty, Robert Michaels, Caryn Palatchi, Anil Panta, Kent Paschke, Mark Pitt, Arindam Sen, Neven Simicevic, Lasitha Weliyanga, Steven P. Wells. 2024-11-15. Nuclear Dependence of Beam Normal Single Spin Asymmetry in Elastic Scattering from Nuclei. https://arxiv.org/abs/2411.10267

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