Speaker
Description
Since its introduction, the so-called surrogate-reaction method (SRM) has motivated the development and improvement of theories in connection to direct reactions. A recent paper~\cite{bou:20} has shown that the assimilation of experimental probabilities in the neutron cross section evaluation process can still be better estimated using tools resulting from the efforts made over the two last decades. In particular, this paper has put forward a new prescription, named after the SRM as extended SRM (ESRM), to convert, with reasonable confidence, measured direct-reaction induced probabilities to pseudo experimental neutron-induced cross sections. Applied to the $^{174}$Yb($^{3}$He,p\gamma)$^{176}$Lu$^*$ transfer reaction, the ESRM has demonstrated much more precision than the standard use of the historical SRM to make that conversion. Beyond 'direct' analysis of direct-reaction induced probabilities using the right modeling as developed in Ref.~\cite{bou:19}, it is worth to try converting the measured probabilities in pseudo experimental neutron-induced cross sections for neutron reactor data applications. In the present talk, we demonstrate that the ESRM is also suitable for fissile isotopes. The ESRM formula will be applied to gamma-emission and fission probabilities measured in the $^{238}$U($^{3}$He,$^{4}$He)$^{237}$U$^*$ reaction, transforming them into neutron-incident (n+$^{236}$U) data. Figure 1, enclosed, extracted from Ref.~\cite{jur:17}, shows the disagreement commonly observed between decay probabilities recovered using the Weisskopf-Ewing limit of the SRM from neutron-incident evaluated cross sections and, the actually measured probabilities.
\bibitem{bou:20} O.~Bouland and G.~Nogu`ere, %{\it Reconciling surrogate-reaction probabilities and neutron-induced cross sections},
Phys. Rev. C {\bf 102}, 054608 (2020).
\bibitem{bou:19} O.~Bouland, %{\it Reexamining fission-probability data using $\mathcal{R}$-matrix Monte Carlo simulations: Beyond the surrogate-reaction method},
Phys. Rev. C {\bf 100}, 064611 (2019).
\bibitem{jur:17} B.~Jurado, P.~Marini \etal~, EPJ Web Conf. 146, 11006 (2017).