Measurements of the Proton Elastic-Form-Factor Ratio μpGEp/GMp at Low Momentum Transfer

作者：Guy Ron, J. Glister, B. Lee, K. Allada, W. Armstrong, J. Arrington, A. Beck, F. Benmokhtar, Barry L. Berman, W. B. Li, E. J. Brash, A. Camsonne, J. R. Calarco, J. P. Chen, Seonho Choi, E. Chudakov, Luminita Coman, Brandon Craver, Francesco Cusanno, J.C. Dumas, Chiranjib Dutta, R. J. Feuerbach, A. Freyberger, S. Frullani, F. Garibaldi, R. Gilman, O. Hansen, Douglas W. Higinbotham, T. Holmstrom, C. E. Hyde-Wright, Hassan Fathy Ibrahim, Y. Ilieva, C. W. de Jager, X. Jiang, M. Jones, H. Kang, A. Kelleher, E. Khrosinkova, E. Kuchina, G. Kumbartzki, J. J. LeRose, R. Lindgren, P. Markowitz, Sönke Beck, Edwin C. McCullough, D. Meekins, M. Meziane, Z.-E. Meziani, R. Michaels, B. Moffit, B. Norum, Yongseok Oh, M. Olson, M. Paolone, Kent D. Paschke, Ch. F. Perdrisat, E. Piasetzky, Milan Potokar, R. Pomatsalyuk, Ishay Pomerantz, A. J. R. Puckett, V. Punjabi, X. Qian, Y. Qiang, Ronald D. Ransome, Meral L. Reyhan, Julie Roche, Yannick Rousseau, A. Saha, A. Sarty, Brad Sawatzky, Eva Christina Schulte, M. Shabestari, A. Shahinyan, R. Shneor, Simon Širca, K. Slifer, P. Solvignon, Jeongseog Song, R.J. Sparks, R. Subedi, S. Strauch, G. M. Urciuoli, K. Wang, B. Wojtsekhowski, Xuefei Yan, H. Yao, Xuebing Zhan, Xianduo Zhu · 发表于：Physical Review Letters · 年份：2007 · DOI：10.1103/physrevlett.99.202002 · 被引用次数：48 · 研究领域：Particle physics theoretical and experimental studies、Quantum Chromodynamics and Particle Interactions、High-Energy Particle Collisions Research

High-precision measurements of the proton elastic form-factor ratio, mu pG p E/G p M, have been made at four-momentum transfer, Q2, values between 0.2 and 0.5 GeV2. The new data, while consistent with previous results, clearly show a ratio less than unity and significant differences from the central values of several recent phenomenological fits. By combining the new form-factor ratio data with an existing cross-section measurement, one finds that in this Q2 range the deviation from unity is primarily due to G p E being smaller than expected.