Proposal of Direct Reaction Cross Section Measurements on an Excited State to Study Explosive Nucleosyntheses

Abstract

High peak power laser has been developed quickly, which leads to generation of new types of radiations such as electrons, gamma-rays, and ion beams from high field plasma generated from interaction between the laser and a target. We have suggested that direct measurements of nuclear reaction cross sections on an exited state in a nucleus using the laser driven radiations.

Explosive Nucleosynthesis Study Using Laser Driven γ-ray Pulses

“…The plasma lifetime is shorter than typical half-lives of excited states in nuclei of astrophysical interest, as shown in Figure 7. This result shows that the two-pulse method [31] using laser with a pulse energy of 10 J is not effective for this type of experiment. This estimation indicates that the high power laser which has been developed to study laser nuclear fusions such as NIF [33] and LFEX [34] is required for the generation of pre-pulse.…”

“…When the plasma generated in 19 F or 190 Pt target can be kept longer than 1 ns, the first excited state in 19 F or 190 Pt can be populated. To measure the cross-section on excited states, Hayakawa and Nakamura proposed nuclear experiments using the following procedure [31]. A laser pulse is divided into a pre-pulse to create hot plasma and a main pulse to generate a high intensity quantum pulse.…”