Ⅳ. OPERATION RECORDS

RIKEN Accel. Prog. Rep. 48 (2015)

AVF operations in 2014
N. Tsukiori,*2 M. Fujimaki,*1 T. Fujinawa,*1 N. Fukunishi,*1 S. Fukuzawa,*2 M. Hamanaka,*2 H. Hasebe, *1Y. Higurashi,*1 E. Ikezawa,*1 H. Imao,*1 S. Ishikawa,*2 T. Kageyama,*1 O. Kamigaito,*1 M. Kase,*1M. Kidera,*1 K. Kobayashi, *2 M. Komiyama,*1 Y. Kotaka,*3 R. Koyama,*2 H. Kuboki,*1 K. Kumagai,*1T. Maie,*1 M. Nagase,*1 T. Nagatomo,*1 T. Nakagawa,*1 M. Nakamura,*1 T. Nakamura,*2 M. Nishida,*2M. Nishimura,*2 J. Ohnishi,*1 Y. Ohshiro,*3 H. Okuno,*1 K. Ozeki,*1 N. Sakamoto,*1 J. Shibata,*2 K. Suda,*1A. Uchiyama,*1 T. Watanabe,*1 Y. Watanabe,*1 K. Yadomi,*2 K. Yamada,*1 and S. Yamaka*3In 2014, the total annual operation time of the K70 AVF
cyclotron (denoted as AVF hereafter) was 2942 hours asshown in Table 1. This was increased by 311 hours
compared with that in 2013. In this duration, the time forbeam tuning was 1240 hours, which was 274 hours longer
than that in 2013. Most of the increased time (311 hours)
was spent on beam tuning because the time for beam tuningfor “Injection to RRC-SRC” was increased to two to threetimes longer than usual, and it took considerable time torecover from problems. On the other hand, the total beam
supply time was 1702 hours, which was classified into three
categories: “Injection to RRC”, “Injection to RRC-SRC”,
and “AVF standalone”. The operation times for these three
categories are listed in Table 1.
All of the beams accelerated by the AVF in 2014 arelisted in Table 2. In this table, the following beams wereaccelerated for the first time in 2014: 16O (4.9 MeV/u), 84Kr(3.97 MeV/u),  (12.5 MeV/u), 11B (5.0 MeV/u), 19F (6.08and 6.768 MeV/u), and  (7.5 MeV/u). The suppliedcourses were as follows (in order of the supplied time): RI
production, RRC-SRC, CRIB, RRC-E5, Student Ex, andE7B.

2013
2631
966

2014
2942
1240

Injection to RRC
Injection to RRC-SRC

738
118208455

AVF standalone
Beam course (AVF standalone) (hr)
E7A
E7B
C038091039

480
18311335
58646Particle
pdd

6Li7Li
7Li11B
12C
16O
18O
19F19F
22Ne
40Ar
56Fe84Kr

E (MeV/u)
12.0
12.0
4.9
6.5
7.5
12.5
11.2
5.6
8.6
5.0
7.0
4.9
6.07
6.08
6.768
6.1
5.2
5.0
3.97

CourseRI production
RI production
RRC-SRC
Student Ex.
RI production
RI production
CRIB
CRIB
E7B
CRIB
RRC-E5
RRC-SRCRI production
RI production
RI production
CRIB
RRC-E5RRC-E5RRC-E5(1) During 40Ar beam tuning, the beam stopped
unexpectedly at RRC. This was due to an incorrect
arrangement of the readout-cable of baffle slits, which cut
across the beam trajectory in the chamber of the RRC.
(2) During 6Li beam supply, the beam current decreased
at the ion source. To investigate the cause, the ion source
was disassembled. Consequently, some contaminations
were observed and lack of 6Li metal was found.
(3) During 12C beam tuning, one of the hollow
conductors from the magnetic channel of the AVF cracked
and cooling water sprayed out from that crack. The crack
was temporarily caulked by putty because it was difficult toclose the crack by weld. The beam tuning was restarted
without any problems.

Table 1. AVF operation statistics in 2014.
Total operation time (hr)Beam tuning

Table 2. AVF beam list in 2014.

The total fault time was 118 hours. The main faults arelisted in Table 3, in descending order of time spent on
restoration, and details are indicated below.

Table 3. Main faults in 2014. See text for details.
(1)
(2)
(3)

Date
6th September
13th May
16th September

Time for restoration (hr)221817

RIKEN Nishina Center
SHI Accelerator Service Ltd.
＊3
Center for Nuclear Study, the university of Tokyo＊1＊2- 327 -

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