A small proton charge radius from an electron–proton scattering experiment

  title={A small proton charge radius from an electron–proton scattering experiment},
  author={W. Xiong and A. Gasparian and H. Gao and D. Dutta and M. Khandaker and N. Liyanage and E. Pasyuk and C. Peng and X. Bai and L. Ye and K. Gnanvo and C. Gu and M. Levillain and X. Yan and D. Higinbotham and M. Meziane and Z. Ye and K. Adhikari and B. Aljawrneh and H. Bhatt and D. Bhetuwal and J. Brock and V. Burkert and C. Carlin and A. Deur and D. Di and J. Dunne and P. Ekanayaka and L. El-Fassi and B. Emmich and L. Gan and O. Glamazdin and M. L. Kabir and A. Karki and C. Keith and S. Kowalski and V. Lagerquist and I. Larin and T. Liu and A. Liyanage and J. Maxwell and D. Meekins and S. J. Nazeer and V. Nelyubin and H. Nguyen and R. Pedroni and C. Perdrisat and J. Pierce and V. Punjabi and M. Shabestari and A. Shahinyan and R. Silwal and S. Stepanyan and A. Subedi and V. Tarasov and N. Ton and Y. Zhang and Z. Zhao},
Elastic electron–proton scattering (e–p) and the spectroscopy of hydrogen atoms are the two methods traditionally used to determine the proton charge radius, r p. In 2010, a new method using muonic hydrogen atoms1 found a substantial discrepancy compared with previous results2, which became known as the ‘proton radius puzzle’. Despite experimental and theoretical efforts, the puzzle remains unresolved. In fact, there is a discrepancy between the two most recent spectroscopic measurements… Expand
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