S. Goko

Photodisintegration cross section measurements on {sup 186}W, {sup 187}Re, and {sup 188}Os: Implications for the Re-Os cosmochronology

Cross sections of the {sup 186}W, {sup 187}Re, {sup 188}Os({gamma},n) reactions were measured using quasimonochromatic photon beams from laser Compton scattering with average energies from 7.3 to 10.9 MeV. The results are compared with the predictions of Hauser-Feshbach statistical calculations using four different sets of input parameters. In addition, the inverse neutron capture cross sections were evaluated by constraining the model parameters, especially the E1 strength function, on the basis of the experimental data. The present experiment helps to further constrain the correction factor F{sub {sigma}} for the neutron capture on the 9.75 keV state in {sup 187}Os. Implications of F{sub {sigma}} for the Re-Os cosmochronology are discussed with a focus on the uncertainty in the estimate of the age of the galaxy.

Measurements of the 152Srn(γ,n) Cross Section with Laser-Compton Scattering γ Rays and the Photon Difference Method

The cross sections of the 152Sm(γ,n) and 197Au(γ,n) reactions have been measured with the laser-Compton scattering (LCS) γ beam in the 8.3–12.4MeV energy range. The photon difference method has been used for LCS γ rays in the data analysis for the first time. The present data for 197Au measured as the standard are in agreement with the preceding data and the recent recommendation. On the other hand, the preceding data for 152Sm at 8.3 MeV are twice as large as the present data.

A new astrophysical γ probe and its applications

Abstract We discuss the properties of γ beams produced by Compton back-scattering of laser light from relativistic electrons at AIST and SPring-8 and their applications to nuclear astrophysics experiments.

Long-Axis Fabry–Pérot Cavity for Intense Laser-Compton Photon Beam

A long-axis Fabry–Perot cavity was designed and installed on one of the straight sections of 800 MeV electron storage ring of National Institute of Advanced Industrial Science and Technology (AIST), to increase the yield of laser-Compton photons by about an order of magnitude compared with the currently obtained value. Resonance in the fundamental mode was achieved, and the cavity finesse was measured to be 660. The cavity gain was estimated to be 75.

Photoreaction Cross Section Measurements for Astrophysics

γ‐ray beams at synchrotron radiation facilities will give us unprecedented opportunities to study photonuclear reactions of astrophysical interest. We report our photonuclear reaction studies and give a prospect of a fertile research field to be pioneered in the next 5 years.

Photodisintegration of {sup 80}Se: Implications for the s-process branching at {sup 79}Se

Photoneutron cross sections were measured for

Photodisintegration of 80Se and its implications for s-process branching

^{80}\mathrm{Se}

Photodisintegration of Deuterium in the Precision Era of Big Bang Nucleosynthesis

immediately above the neutron separation energy with quasimonochromatic

Photoneutron Cross Sections for Nuclear Astrophysics

\ensuremath{\gamma}

Cross-section measurements of the Ta-181(gamma ,n)Ta-180 reaction near neutron threshold and the p process nucleosynthesis

-ray beams to experimentally constrain the