There is a growing consensus in recent multi-messenger astronomy that the explosions of single massive stars, i.e. supernovae (SNe) and collapsars, dominate the heavy-element production over the entire history of cosmic evolution, while the neutron-star mergers could contribute only partly in the recent epoch because of long time-delay due to slow GW radiation [1]. We will first discuss when...
In UVSOR synchrotron facility at Institute for Molecular Science, an ultra-short pulsed gamma-ray source was developed by the 90-degree interaction between a 750-MeV electron beam and a Ti:Sa laser pulse. The maximum energy of the gamma rays is 6.6 MeV and the pulse width is calculated to be 5 ps (FWHM). Using the ultra-short pulsed gamma rays, gamma-ray-induced positron annihilation...
The study of photo-nuclear reactions is crucial for understanding nuclear structure and astrophysical processes. The PANDORA (Photo-Absorption of Nuclei and Decay Observation for Reactions in Astrophysics) project aims to systematically investigate these reactions in nuclei with mass numbers below 60. We will use virtual photon exchange through proton scattering and high-intensity real-photon...
The Shanghai Laser Electron Gamma Source (SLEGS), a quasi-monoenergetic gamma-ray source based on laser Compton scattering, utilizes the interaction between the 3.5 GeV electron beam at the Shanghai Synchrotron Radiation Facility (SSRF) and a CO₂ laser. It delivers high-quality gamma-ray beams with tunable energies ranging from 0.66 to 21.7 MeV. For photoneutron cross section measurements,...
A Monte Carlo simulation code and an analytical calculation code for polarization study were developed at Shanghai Laser Gamma Source (SLEGS), employing the unique laser Compton slant scattering (LCSS) mode. The intensity of spatial distributions and its Stokes parameters are simulated for LCSS of linearly/circularly polarized laser photons and unpolarized relativistic electrons. The...
The interaction of photons with relativistic electrons constitutes a fundamental electromagnetic process whose polarization transfer mechanics remain incompletely characterized. We report the first systematic measurement of spatial polarization distribution for 𝛾-rays generated via 45◦ slant Inverse Compton Scattering (ICS) between linearly polarized 0.117 eV photons and 3.5 GeV electrons,...
We evaluate uncertainty of peak energy of giant dipole resonance (GDR), propagated from uncertainty of parameters of Skyrme interaction. The Monte Carlo calculation of the random phase approximation using randomized Skyrme parameters is performed. Under the condition that the correlations between each of the Skyrme parameters is considered, the GDR peak energy has the uncertainty of $\sim$ 1...
