A benchmark experiment on (208)Pb shows that polarized proton inelastic scattering at very forward angles including 0° is a powerful tool for high-resolution studies of electric dipole (E1) and spin magnetic dipole (M1) modes in nuclei over a broad excitation energy range to test up-to-date nuclear models. The extracted E1 polarizability leads to a neutron skin thickness r(skin) = 0.156(-0.021)(+0.025) fm in (208)Pb derived within a mean-field model [Phys. Rev. C 81, 051303 (2010)], thereby constraining the symmetry energy and its density dependence relevant to the description of neutron stars.

The level structure of 30 S was studied via the 28 Si( 3 He,n) and 32 S(p,t) reactions at the Nuclear Science Laboratory (NSL) of the University of Notre Dame and the Research Center for Nuclear Physics (RCNP) of the University of Osaka, Japan. Important experimental information on the energy levels, decay branching ratios and tentative spin assignments are extracted to calculate the reaction rates for 29 P(p,γ) 30 S and 26 Si(α,p) 29 P, which play a critical role for reaction flow in explosive hydrogen burning.

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The Multi-Pixel Photon Counter (MPPC) is one of the devices called SiPM (silicon photomultiplier). Many MPPCs have been used for positron emission tomography (PET) and high energy physics experiments, but to further improve the performance of these applications, new MPPCs are required. We developed new MPPCs designed for time-of-flight PET (TOF-PET) that have high photon detection efficiency (PDE) for the scintillation light used in this application, as well as good timing resolution. We incorporated these detectors into MPPC modules for TOF-PET, resulting in excellent coincidence resolving time (CRT). We also developed new MPPCs suitable for high energy physics experiments, such as Cherenkov telescopes. These new MPPCs have high PDE for the Cherenkov light generated by high energy cosmic rays and gamma rays, and the detectors' optical crosstalk was drastically reduced by removing the resin coating. In addition to developing these application-specific MPPCs, we also decreased the size of an MPPC's microcells because small microcells are required to detect more photons. We reduced the microcell's cell pitch down to 10µm and 15µm and added trenches to suppress crosstalk and dark counts. These new MPPCs have improved linearity and almost the same fill factor as trench-less conventional models that have a small cell size.