The QDMDQ magnetic spectrograph “RAIDEN” (II) Correction of kinematic line broadening

Kinematic line broadening of the image was corrected by using multipole magnetic fields for the spectrograph “RAIDEN” at the Research Center for Nuclear Physics (RCNP).

Arrival positions of the collimated rays with various angles of incidence were measured at the focal line as a function of strengths of the multipole magnetic fields. Measurements were performed for various values of the kinematic factor of nuclear particles scattered from the target nucleus. Strengths of the multipole fields which achieved the best directional focussing were extracted from the measured results. The strengths were proportional to the kinematic factor and the kinematic line broadening was corrected up to higher order in the median plane.