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Title: Measured proton electromagnetic structure deviates from theoretical predictions

Abstract

The visible world is founded on the proton, the only composite building block of matter that is stable in nature. Consequently, understanding the formation of matter relies on explaining the dynamics and the properties of the proton's bound state.A fundamental property of the proton involves the response of the system to an external electromagnetic field. It is characterized by the electromagnetic polarizabilities that describe how easily the charge and magnetization distributions inside the system are distorted by the electromagnetic field. Moreover, the generalized polarizabilities map out the resulting deformation of the densities in a proton subject to an electromagnetic field. They disclose essential information about the underlying system dynamics and provide a key for decoding the proton structure in terms of the theory of the strong interaction that binds its elementary quark and gluon constituents. Of particular interest is a puzzle in the electric generalized polarizability of the proton that remains unresolved for two decades. Here we report measurements of the proton's electromagnetic generalized polarizabilities at low four-momentum transfer squared. We show evidence of an anomaly to the behaviour of the proton's electric generalized polarizability that contradicts the predictions of nuclear theory and derive its signature in the spatial distributionmore » of the induced polarization in the proton. The reported measurements suggest the presence of a new, not-yet-understood dynamical mechanism in the proton and present notable challenges to the nuclear theory.« less

Authors:
 [1]; ORCiD logo [1]; ORCiD logo [1];  [2]; ORCiD logo [3];  [4]; ORCiD logo [5];  [6];  [7];  [8];  [2];  [2]; ORCiD logo [2];  [1];  [9];  [2]; ORCiD logo [2];  [10];  [11];  [2] more »;  [6];  [11];  [1]; ORCiD logo [12];  [9];  [11];  [11];  [13];  [5];  [14];  [2];  [15];  [2]; ORCiD logo [12];  [16];  [17];  [6];  [18];  [19];  [1]; ORCiD logo [2]; ORCiD logo [2];  [13];  [6];  [15]; ORCiD logo [4];  [13] « less
  1. Temple Univ., Philadelphia, PA (United States)
  2. Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
  3. New Mexico State Univ., Las Cruces, NM (United States)
  4. Univ. of Virginia, Charlottesville, VA (United States)
  5. College of William and Mary, Williamsburg, VA (United States)
  6. Catholic Univ. of America, Washington, DC (United States)
  7. Hampton Univ., Hampton, VA (United States); Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States)
  8. Temple Univ., Philadelphia, PA (United States); Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States)
  9. Mississippi State Univ., Mississippi State, MS (United States)
  10. Old Dominion Univ., Norfolk, VA (United States)
  11. Univ. of Regina, SK (Canada)
  12. Argonne National Lab. (ANL), Lemont, IL (United States)
  13. Duke Univ., Durham, NC (United States)
  14. Hampton Univ., Hampton, VA (United States)
  15. Florida International Univ. (FIU), Miami, FL (United States)
  16. Artem Alikhanian National Lab., Yerevan (Armenia)
  17. Univ. of Tennessee, Knoxville, TN (United States)
  18. Veer Kunwar Singh Univ., Arrah (India)
  19. Univ. of Pavia (Italy); Istituto Nazionale di Fisica Nucleare (INFN), Pavia (Italy)
Publication Date:
Research Org.:
Temple Univ., Philadelphia, PA (United States); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Nuclear Physics (NP)
OSTI Identifier:
1895351
Alternate Identifier(s):
OSTI ID: 1896663
Report Number(s):
JLAB-PHY-22-3744; DOE/OR/23177-5638; arXiv:2210.11461
Journal ID: ISSN 0028-0836; TRN: US2310375
Grant/Contract Number:  
SC0016577; AC05-06OR23177
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Nature (London)
Additional Journal Information:
Journal Volume: 611; Journal Issue: 7935; Journal ID: ISSN 0028-0836
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; Experimental nuclear physics; Theoretical nuclear physics

Citation Formats

Li, R., Sparveris, Nikos, Atac, Hamza, Jones, M. K., Paolone, Michael, Akbar, Z., Gayoso, Carlos Ayerbe, Berdnikov, V., Biswas, D., Boer, M., Camsonne, A., Chen, J. -P., Diefenthaler, Markus, Duran, B., Dutta, D., Gaskell, D., Hansen, Jens-Ole, Hauenstein, F., Heinrich, N., Henry, W., Horn, T., Huber, G. M., Jia, S., Joosten, Sylvester, Karki, A., Kay, S. J. D., Kumar, V., Li, X., Li, W. B., Liyanage, A. H., Malace, S., Markowitz, P., McCaughan, M., Meziani, Zein-Eddine, Mkrtchyan, H., Morean, C., Muhoza, M., Narayan, A., Pasquini, B., Rehfuss, M., Sawatzky, Brad, Smith, Gregory R., Smith, A., Trotta, R., Yero, C., Zheng, Xiaochao, and Zhou, J. Measured proton electromagnetic structure deviates from theoretical predictions. United States: N. p., 2022. Web. doi:10.1038/s41586-022-05248-1.
Li, R., Sparveris, Nikos, Atac, Hamza, Jones, M. K., Paolone, Michael, Akbar, Z., Gayoso, Carlos Ayerbe, Berdnikov, V., Biswas, D., Boer, M., Camsonne, A., Chen, J. -P., Diefenthaler, Markus, Duran, B., Dutta, D., Gaskell, D., Hansen, Jens-Ole, Hauenstein, F., Heinrich, N., Henry, W., Horn, T., Huber, G. M., Jia, S., Joosten, Sylvester, Karki, A., Kay, S. J. D., Kumar, V., Li, X., Li, W. B., Liyanage, A. H., Malace, S., Markowitz, P., McCaughan, M., Meziani, Zein-Eddine, Mkrtchyan, H., Morean, C., Muhoza, M., Narayan, A., Pasquini, B., Rehfuss, M., Sawatzky, Brad, Smith, Gregory R., Smith, A., Trotta, R., Yero, C., Zheng, Xiaochao, & Zhou, J. Measured proton electromagnetic structure deviates from theoretical predictions. United States. https://doi.org/10.1038/s41586-022-05248-1
Li, R., Sparveris, Nikos, Atac, Hamza, Jones, M. K., Paolone, Michael, Akbar, Z., Gayoso, Carlos Ayerbe, Berdnikov, V., Biswas, D., Boer, M., Camsonne, A., Chen, J. -P., Diefenthaler, Markus, Duran, B., Dutta, D., Gaskell, D., Hansen, Jens-Ole, Hauenstein, F., Heinrich, N., Henry, W., Horn, T., Huber, G. M., Jia, S., Joosten, Sylvester, Karki, A., Kay, S. J. D., Kumar, V., Li, X., Li, W. B., Liyanage, A. H., Malace, S., Markowitz, P., McCaughan, M., Meziani, Zein-Eddine, Mkrtchyan, H., Morean, C., Muhoza, M., Narayan, A., Pasquini, B., Rehfuss, M., Sawatzky, Brad, Smith, Gregory R., Smith, A., Trotta, R., Yero, C., Zheng, Xiaochao, and Zhou, J. 2022. "Measured proton electromagnetic structure deviates from theoretical predictions". United States. https://doi.org/10.1038/s41586-022-05248-1. https://www.osti.gov/servlets/purl/1895351.
@article{osti_1895351,
title = {Measured proton electromagnetic structure deviates from theoretical predictions},
author = {Li, R. and Sparveris, Nikos and Atac, Hamza and Jones, M. K. and Paolone, Michael and Akbar, Z. and Gayoso, Carlos Ayerbe and Berdnikov, V. and Biswas, D. and Boer, M. and Camsonne, A. and Chen, J. -P. and Diefenthaler, Markus and Duran, B. and Dutta, D. and Gaskell, D. and Hansen, Jens-Ole and Hauenstein, F. and Heinrich, N. and Henry, W. and Horn, T. and Huber, G. M. and Jia, S. and Joosten, Sylvester and Karki, A. and Kay, S. J. D. and Kumar, V. and Li, X. and Li, W. B. and Liyanage, A. H. and Malace, S. and Markowitz, P. and McCaughan, M. and Meziani, Zein-Eddine and Mkrtchyan, H. and Morean, C. and Muhoza, M. and Narayan, A. and Pasquini, B. and Rehfuss, M. and Sawatzky, Brad and Smith, Gregory R. and Smith, A. and Trotta, R. and Yero, C. and Zheng, Xiaochao and Zhou, J.},
abstractNote = {The visible world is founded on the proton, the only composite building block of matter that is stable in nature. Consequently, understanding the formation of matter relies on explaining the dynamics and the properties of the proton's bound state.A fundamental property of the proton involves the response of the system to an external electromagnetic field. It is characterized by the electromagnetic polarizabilities that describe how easily the charge and magnetization distributions inside the system are distorted by the electromagnetic field. Moreover, the generalized polarizabilities map out the resulting deformation of the densities in a proton subject to an electromagnetic field. They disclose essential information about the underlying system dynamics and provide a key for decoding the proton structure in terms of the theory of the strong interaction that binds its elementary quark and gluon constituents. Of particular interest is a puzzle in the electric generalized polarizability of the proton that remains unresolved for two decades. Here we report measurements of the proton's electromagnetic generalized polarizabilities at low four-momentum transfer squared. We show evidence of an anomaly to the behaviour of the proton's electric generalized polarizability that contradicts the predictions of nuclear theory and derive its signature in the spatial distribution of the induced polarization in the proton. The reported measurements suggest the presence of a new, not-yet-understood dynamical mechanism in the proton and present notable challenges to the nuclear theory.},
doi = {10.1038/s41586-022-05248-1},
url = {https://www.osti.gov/biblio/1895351}, journal = {Nature (London)},
issn = {0028-0836},
number = 7935,
volume = 611,
place = {United States},
year = {Wed Oct 19 00:00:00 EDT 2022},
month = {Wed Oct 19 00:00:00 EDT 2022}
}

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