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We report on efforts to develop reliable photonuclear cross section and photon strength function data by measuring, compiling, assessing, evaluating the available data, and producing tables of Giant Dipole Resonance parameters and global models for use in basic sciences and applications. [ABSTRACT FROM AUTHOR]

The γ-ray strength function is a key statistical nuclear ingredient to the s-, r- and p-process nucleosynthesis of heavy elements. It has recently become apparent that extra γ-ray strengths that appear near neutron threshold on top of the low-energy tail of GDR play an important role in neutron capture and photodisintegration. We discuss extra γ-ray strengths of pigmy E1 and giant M1 nature based on the latest experimental photoneutron cross sections measured with laser Compton scattering γ-rays. [ABSTRACT FROM AUTHOR]

Presented in this paper are some of the latest measurements of photoneutron cross sections of direct relevance to the p-process nucleosynthesis in the context of the statistical model of compound nuclear reactions. We discuss the p-process origin of the rarest nuclide and the only naturally occurring isomer 180Tam, a serious underproduction problem of 138La, and the nuclear level density of 180Ta determined from the partial photoneutron cross section for 180Tam. As the laser-Compton scattering γ ray at AIST has enabled one to directly determine (γ,n) cross sections, the blackbody synchrotron radiation to be produced by a ten-Tesla superconducting wiggler at SPring-8 is expected to be a promising tool for exploring (γ,α) and (γ,p) reactions in the future. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

Photodisintegration cross sections were measured for 80Se with laser Compton scattering γ beams at Eγ=9.98–11.80 MeV near the neutron separation energy. The stellar neutron capture rate for 80Se was evaluated by using the photodisintegration data as constraints on the E1 γ strength function for 80Se within the framework of the Hauser-Feshbach statistical model. It was found that the rate at 30 keV is 0.7–1.1 times that of Bao and Käppeler. s-process temperatures deduced from the empirical solar abundances of the s-only nuclei 79Se and 80Kr with this neutron capture rate are 17–25 keV in the neutron density rage of (0.8–1.9)×103/cm3. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

Direct determination of photodisintegration cross sections with quasi-monochromatic γ rays from laser Compton scattering has shed new light on nucleosynthesis. Presented here are results of photoneutron cross-section measurements dedicated to investigating the origin of 180Tam, the only naturally occurring isomer and the rarest isotope in the solar system. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

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. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

Photodisintegration cross sections were measured for deuterium with Laser Compton scattering γ beams at Eγ = 2.3 – 4.6 MeV. The experimental evaluation of R(E) = Naσv for the p(n,γ)D reaction was performed in the energy region relevant to big bang nucleosynthesis (BBN) by using the present data combined with the preceding data. The result confirms the past theoretical evdaluation with 6% uncertainty. The reaction rate for the p(n,γ)D reaction is presented for the BBN in the precision era. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

Photoneutron cross sections for three Pb isotopes (206Pb, 207Pb, 208Pb) near neutron threshold were measured with the laser inverse-Compton scattering gamma rays at the National Institute of Advanced Industrial Science and Technology. The cross section data are presented. [ABSTRACT FROM AUTHOR]

M1 and E1 transition cross sections in the D(y→, n) reaction were separately determined by measuring the analyzing power for emitted neutrons with linearly-polarized γ rays at four energies between 2.26 MeV and 3.70 MeV near reaction threshold at 2.224 MeV. We compared the experimental result with the JENDL evaluated data. [ABSTRACT FROM AUTHOR]

The article reports on the result of the study which focuses on measuring the strength of tin (Sn) photoneutrons. The strength of 116Sn and 117 were measured with the utilization of the TALYS reaction code, Lorentzian model and Skyrme HFB plus quasiparticle random phase approximation (QRPA) model. It was found that Sn has low-lying strength based on the data provided by nuclear resonance fluorescence.