Extracting (n,γ) direct capture cross sections from Coulomb dissociation: Application toC14(n,γ)C15

Abstract

A methodology for extracting neutron direct capture rates from Coulomb dissociation data is developed and applied to the Coulomb dissociation of $^{15}\mathrm{C}$ on $^{208}\mathrm{Pb}$ at 68 MeV/nucleon. Full continuum discretized coupled channel calculations are performed and an asymptotic normalization coefficient is determined from a fit to the breakup data. Direct neutron capture calculations using the extracted asymptotic normalization coefficient provide $(n,\ensuremath{\gamma})$ cross sections consistent with direct measurements. Our results show that the Coulomb dissociation data can be reliably used for extracting the cross section for $^{14}\mathrm{C}$($n,\ensuremath{\gamma}$)$^{15}\mathrm{C}$ if the appropriate reaction theory is used. The resulting error bars are of magnitude comparable to those from the direct measurement. This procedure can be used more generally to extract capture cross sections from breakup reactions whenever the desired capture process is fully peripheral.