Development of HPGE detector for the longitudinal emittance measurement.

摘要

The longitudinal emittance of the beam from the RIKEN Ring Cyclotron (RRC) is indispensable knowledge for the operation of the Radioactive Isotope Beam Factory, which is now under construction and uses the RRC as an injector. We proposed to employ a HPGe detector as a compact and convenient energy detector for longitudinal emittance measurements and studied the feasibility of its use with high-energy heavy ions. A reasonably good energy resolution, δ E/E = 6.5 × 10−4, has been observed for 1890-MeV 14N, which makes the HPGe promising. A new detector is being fabricated to achieve a better resolution. Also the longitudinal emittances were measured for 3800-MeV 40Ar and 2420-MeV 22Ne. It has been demonstrated that the measurement of longitudinal emittance provides rich information on the acceleration condition, such as the single-turn extraction and the effect of phase compression, and is very helpful for the beam tuning of the present and new facilities.