TRIAC Progress Report - KEK

a diagonal direction. The monitors are followed by Faraday cups, FC-LBT01 and
FC-LBT02, respectively. For monitoring the intensity of RIB just upstream of the
KEKCB, a plastic scintillator (2 x 2 x 2 cm 3 ), SCI-LBT01 in Fig. 2-34, is installed in
the injection side of the KEKCB. It was covered by an aluminum plate of 100-µm thick
where the RIB was implanted. The detection efficiency for β-rays from the implanted
RIBs is about 50 %.
After being charge-bred, the RIB with a higher charge state is transported through
the second part of LBT to ACC. The ion-optical configuration between the KEKCB and
ACC is also shown in Fig. 2-34. The first component of 2MQ-MD-2MQ is dedicated to
charge state analysis of ions extracted from the KEKCB. The resolving power of
mass-to-charge state ratio (A/q) is designed to be (A/q)/δ(A/q) = 128 for the beams with
emittance of 100π mm•mrad. Three Faraday cups (FC-LBTFi, i = 1, 2, 3) and three
plastic scintillators (SCI-LBTFi, i = 1, 2, 3) are installed at F1, F2 and F3 chambers. A
beam profile monitor, BPM-LBT04, is installed between F1 and F2 chambers. The
designed acceptance of the second part of LBT is also 200π mm•mrad. Figure 2-35
shows the result of ion optical simulation with an initial emittance of 200π mm•mrad by
using the GIOS code.
Fig. 2-34 .Ion transporting optical components and beam monitors for low energy beam transport.
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