Compton scattering from He 4 at the TUNL HI γ S facility

Li, X.; Ahmed, M. W.; Banu, A.; Bartram, C.; Crowe, B.; Downie, E. J.; Emamian, M.; Feldman, G.; Gao, H.; Godagama, D.; Grießhammer, H. W.; Howell, C. R.; Karwowski, H. J.; Kendellen, D. P.; Kovash, M. A.; Leung, K. K. H.; Markoff, D.; Mikhailov, S.; Pywell, R. E.; Sikora, M. H.; Silano, J. A.; Sosa, R. S.; Spraker, M. C.; Swift, G.; Wallace, P.; Weller, H. R.; Whisnant, C. S.; Wu, Y. K.; Zhao, Z. W.

doi:10.1103/physrevc.101.034618

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Compton scattering from He 4 at the TUNL HI γ S facility

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Abstract

Differential cross sections for elastic Compton scattering from 4 He have been measured with high statistical precision at the High Intensity γ-ray Source at laboratory scattering angles of 55°, 90°, and 125° using a quasi-monoenergetic photon beam with a weighted mean energy value of 81.3 MeV. The results are compared to previous measurements and similar fore-aft asymmetry in the angular distribution of the differential cross sections is observed. Lastly, this experimental work is expected to strongly motivate the development of effective-field-theory calculations of Compton scattering from 4 He to fully interpret the data.

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Li, X., Ahmed, M. W., Banu, A., Bartram, C., Crowe, B., Downie, E. J., Emamian, M., Feldman, G., Gao, H., Godagama, D., Grießhammer, H. W., Howell, C. R., Karwowski, H. J., Kendellen, D. P., Kovash, M. A., Leung, K. K. H., Markoff, D., Mikhailov, S., Pywell, R. E., Sikora, M. H., Silano, J. A., Sosa, R. S., Spraker, M. C., Swift, G., Wallace, P., Weller, H. R., Whisnant, C. S., Wu, Y. K., Zhao, Z. W.. 2020-03-30. Compton scattering from He 4 at the TUNL HI γ S facility. https://doi.org/10.1103/physrevc.101.034618

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