The future γ -multidetector PARIS for SPIRAL2 will be an array composed of the recently developed LaBr3 scintillators. It is dedicated to the study of the γ -radiation from hot nuclei. Different physics cases are proposed for this detector: one of them is the radiative capture of light-heavy ions. This paper presents a status of knowledge for this physics case and shows which improvements could be provided by the use of PARIS illustrated in the case of 12C(16O,γ )28Si.