The high resolution SHARAQ spectrometer is under construction at the RI Beam Factory (RIBF) at RIKEN, Japan. The spectrometer will be used in nuclear physics experiments using a variety of radioactive isotope (RI) beams from BigRIPS. Among the physics programs proposed, the most characteristic one is a new missing mass spectroscopy with an RI beam as probe.
RI beams have a larger variety of isospin T, spin S, and internal energy compared to light stable beams such as p, d, and 3,4He and minimum internal energies. Due to these properties RI beam induced reactions have the unique potential of more extensive studies of nuclear many body systems. The energies (100-300 MeV/A) of the RI beams of RIBF are well matched for spectroscopic purposes, because at these energies the nucleon-nucleon interaction is weakest. Also, at these energies the spin-isospin modes are stronger excited than the spin-isospin independent modes. Thus poorly known giant resonances can be studied, such as isovector spin monopole and double Gamow-Teller resonances. Also of interest are spectroscopic studies of tetra-neutron states (n4) and superheavy hydrogen isotopes.
To achieve the required high momentum (dp/p =1/15000) and angular (dΦ < 1 mrad) resolutions with a secondary beam with intrinsically large emittance and momentum spread, full dispersion matching techniques have to be employed. An overview of the SHARAQ spectrometer and the proposed physics program will be presented.