Annual Report 2016

We are pleased to release this report on our activities in 2016 at Research Center for Nuclear Physics.

At the Ring Cyclotron Facility, CAGRA+GR campaign experiments were carried out. CAGRA, which stands Clover Array Gamma-ray spectrometer at RCNP/RIBF for Advanced research, was placed at the target position of the high-resolution spectrometer, Grand Raiden (GR). The campaign experiments aimed at studying the nature of the pygmy dipole resonances, isovector spin-flip responses of nuclei for astrophysical neutrino-nucleus inelastic scattering, and so on. The preliminary results show the high prospects of the high-resolution coincidence measurements with a particle spectrometer and a gamma-detector array.

A new project for realizing targeted alpha therapy using a short-lived alpha emitter ²¹¹At has been also started in collaboration with Graduate School of Medicine and Graduate School Science as a high priority interdisciplinary project at Osaka University. The outline of the project will be given in this report.

For hadron physics, preparation for an experiment on charmed baryon spectroscopy via the p(π⁻, D^∗−) reaction has been in progress at J-PARC. The R&D status of the detector components will be reported. The experiment using a high-resolution and large acceptance calorimeter (BGOegg) in conjunction with a high time-resolution TOF system was performed at LEPS2, in order to search for the η′-mesic-nuclei. After the summer in 2016, the main detector system switched from BGOegg to a 1-T solenoid spectrometer. The status of the new detector system will be reported.

In the theory division, the intensive lattice-QCD study by means of HAL-QCD method has been carried out. One of the major findings is that the Zc(3900) is not a conventional resonance but the threshold cusp just opening the D ̅D ^* threshold assisted by the strong πJ/ψ- D ̅D^* coupling. There is also progress in the study of the QCD in finite-temperature using the lattice numerical simulations. The study will shed lights on experimental results from relativistic heavy ion collider experiments in the world.

There are many other actives and progresses in this online report. I hope you will find them interesting!

Sincerely yours,

Takashi Nakano
Director of Research Center for Nuclear Physics