A Magnet Spectrometer Facility: Rationale and Science Themes

The construction of a cosmic-ray facility is proposed. It consists of a large superconducting magnet spectrometer combined with interchangeable detector systems. This facility will address a number of significant topics in cosmic-ray astrophysics, such as the search for antiprotons and antimatter, measurements of electrons and positrons, precision measurements of energy spectra of cosmic-ray nuclei, determination of isotopic abundances at high energies, and observations of high-energy nucleus-nucleus interactions. The magnet-spectrometer facility will make use of the capabilities of the Space Station, such as assembly and servicing in space, and thus planning and design efforts for the facility should proceed simultaneously with the definition work for the Space Station. The importance of an ongoing program of detector development at the participating institutions is stressed.