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arXiv · 0907.3433

Photodisintegration of $^4$He into p+t

R. Nasseripour·B. L. Berman·N. Benmouna·Y. Ilieva·J. -M. Laget
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Abstract

The two-body photodisintegration of $^4$He into a proton and a triton has been studied using the CEBAF Large-Acceptance Spectrometer (CLAS) at Jefferson Laboratory. Real photons produced with the Hall-B bremsstrahlung-tagging system in the energy range from 0.35 to 1.55 GeV were incident on a liquid $^4$He target. This is the first measurement of the photodisintegration of $^4$He above 0.4 GeV. The differential cross sections for the $γ$$^4$He$\to pt$ reaction have been measured as a function of photon-beam energy and proton-scattering angle, and are compared with the latest model calculations by J.-M. Laget. At 0.6-1.2 GeV, our data are in good agreement only with the calculations that include three-body mechanisms, thus confirming their importance. These results reinforce the conclusion of our previous study of the three-body breakup of $^3$He that demonstrated the great importance of three-body mechanisms in the energy region 0.5-0.8 GeV .

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R. Nasseripour, B. L. Berman, N. Benmouna, Y. Ilieva, J. -M. Laget. 2009-07-20. Photodisintegration of $^4$He into p+t. https://doi.org/10.1103/physrevc.80.044603

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