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Polarization degrees of freedom in photoinduced two-nucleon knockout from finite nuclei

Jan Ryckebusch·Dimitri Debruyne·Wim Van Nespen
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Abstract

The polarization degrees of freedom in photoinduced two-nucleon knockout from finite nuclei are studied. It is pointed out that they open good perspectives to study the dynamics of dinucleons in the medium in detail. The ($γ,pp$) and ($γ,pn$) angular cross sections, photon asymmetries and outgoing nucleon polarizations are calculated for the target nuclei $^{16}$O and $^{12}$C and photonenergies ranging from 100 up to 500 MeV. It is investigated to which degree the two-nucleon emission reaction is dominated by photoabsorption on $^3S_1(T=0)$ proton-neutron and $^1S_0(T=1)$ proton-proton pairs in the nuclear medium. The calculations demonstrate that dominance of $S$ wave photoabsorption in the ($γ,pn$) channel does not necessarily imply that the reaction mechanism is similar to what is observed in deuteron photodisintegration.

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Jan Ryckebusch, Dimitri Debruyne, Wim Van Nespen. 1997-10-01. Polarization degrees of freedom in photoinduced two-nucleon knockout from finite nuclei. https://doi.org/10.1103/physrevc.57.1319

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