The reaction particle spectrograph 'RAIDEN'

The reaction analyzer with invaluable dispersion of energy named RAIDEN was designed and constructed. This analyzer is a hybrid type spectrograph with a multipole field. The spectrograph consists of two quadrupole, two dipole and one multipole field magnets, and the magnets are arranged as quadrupole, dipole, multipole, dipole, quadrupole. The obtained maximum resolving power of momentum is 20400, and the maximum collection solid angle is 13 msr. The multipole field compensates various distortion due to the change of excitation condition. The multipole field is also effective to reduce the kinematic effect. The uniformity of the magnetic field due to the accuracy of manufacturing is 1/10000 for all the magnet pole surfaces. The carbon content of the magnet iron is 0.005 percent. The machining of the pole edge was made by a numerically controlled machine. The shape of the pole edge was designed by using the Rogowski curve. The optimization of the shape of magnets was made by the computer codes LINDA and TRIM. The construction of the spectrograph started in 1974, and finished in 1976. At present, the spectrograph is used for the analysis of nuclear reaction particles at the Research Center for Nuclear Physics. (Kato, T.)