Studies of $\phi$ meson mass modification in cold nuclear matter in p+A collisions at J-PARC

The J-PARC E88 experiment is proposed to study the in-medium modification of the 𝜙 meson mass using high-statistics 𝐾+𝐾− decay measurements in proton-nucleus collisions. We study 𝜙 mass dependence on momentum to evaluate ⟨𝑠𝑠⟩ condensate in the nucleon with the mass shift extrapolated to zero momentum. We also aim to study the slopes of the mass shift as a function of the momentum-squared for longitudinally and transversely polarized $\phi$s, which are closely related to higher-order quark and gluon condensates than $\langle \overline{q}q \rangle$. For Kaon identification, we will introduce detectors: Multi-gap Resistive Plate Chambers, Start Counters, and Aerogel Cherenkov counters at the forward angles in the E16 Spectrometer. In April-June 2024, we tested these detectors to evaluate the particle identification performance.