An experiment at J-PARC, E16 experiment, which aims to measure the spectral modification of vector meson in nuclear matter is planned. The experiment will measure light vector mesons (ρ/ω/ϕ mesons) generated in nuclear target through the 30 GeV p+A reactions. The mass spectra can be reconstructed with e + e − pairs originating from their decays. The spectral modification in finite baryon density is studied systematically. The detail of the experimental plan and expected results are presented with a particular focus on first physics run.

No abstract

The J-PARC E16 experiment at the upcoming J-PARC high-momentum beam line is proposed to study the spectral modification of vector mesons in nuclei through the 30-GeV p+A reactions. The high precision measurement with high statistics enables to investigate the dependence of spectral modification on the size of target nuclei, and also on the momentum of ϕ mesons systematically. The detectors have been developed and sufficient performances are achieved for the experiment. An expected mass spectrum including achieved performance is presented.

We plan to conduct a new experiment for the γd → pηn reaction using the FOREST detector at the Research Center for Electron Photon Science, Tohoku University, Japan. The main objective is to determine the low-energy η-neutron scattering parameters. The photon beam with energies around 930 MeV can give the recoilless condition of η mesons by detecting the protons at 0• . The effects of the the η-neutron final-state interaction must be enhanced due to the small relative momentum between an η meson and a residual neutron. In this contribution, the planned FOREST experiment is presented.

No abstract