Measurement of Vector Meson Mass in Nuclear Matter at J-PARC

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.