Experimental Study of In-medium Spectral Change of Vector Mesons at J-PARC

Chiral symmetry and its spontaneous breaking is an essential property of the QCD vacuum and is closely related to the generation of hadron mass. J-PARC E16 experiment measures dielectron spectra in p+A collisions at 30 GeV to study the in-medium spectral change of vector mesons that signals the partial restoration of the broken symmetry. The experiment uses the primary proton beam available at the high-momentum beam line of the J-PARC hadron experimental facility. We performed three proton-beam runs intended for beamline and detector commissioning. We are preparing for the next commissioning run in 2023 and the first physics run. We present the experimental setup, some of the expected results, preparation status, and some findings in the commissioning runs.