PRESENT STATUS OF BABY CYCLOTRON
T. Yamada
Accelerator Group, The Japan Steel Works, Ltd. Muroran
4 Chatsu-Machi, Muroran Hokkaido, JapanABSTRACTBABY CYCLOTRON FOR MEDICAL USE

Ultra-compact eye 1otron named as "BABY CYCLOTRON"
developed by Japan Steel Works. Baby Cyclotron wasdesigned to produce of short-lived isotopes such as
C-11, N-13, 0-15 and F-18 for clinical diagnosis.
Prototype was completed in 1978 and was installed atNAKANO National Chest Hospital in Tokyo. After that,six machines have been delivered for Montreal Neurological Institute, Brookhaven National Laboratory inNew York, Research Institute for Brain & Blood Vessels
Akita, Kyushu University. Gumma University and NIKKO
Memoreal Hospital and now make a great contribution toexpand of nuclear medical reseach.
At present, K = 30MeV machine is under manufacturing for university of Pennsylvania.
On the one-hand, Baby Cyclotron have come to beutilized in various other areas such as to be used toanalyze impurities in semiconductor substance by beam
bombarding, study of new materials for nuclear fusion
reactor and neutron source for Neutron Radiography
Testing.
Photo 1 shows outlook of the Baby Cyclotron.

Prototype was designed to accelerate of proton
10MeV and deuteron 5Mev. After that, we made three
type machines which has enough ability to produce
radioisotopes for clinical diagnosis, and special
attention has been paid in derive features as follows:
1) Fixed energy and four sectors azimuthally varyingfield,2) compact figure desired hospital's nuclear medicaldepartment,
3) A bitter type magnet yoke shielding activity,
4) Simple control and operation,5) Easy maintenance without skilled personnel.
Performance ratings of Baby Cyclotron are shown inTable 1 and Table 2 show examples of our radioisotope
production test with BC1710.

Photo 1Outlook of the Baby Cyclotron

31APPLICATION OF BABY CYCLOTRON TO OTHER AREAS

Table 1 Performance Ratings of the Baby Cyclotron

A Baby Cyclotron (BC168) delivered by us toIbaraki Electrical communication Research Institute ofthe Nippon Telephone and Telegraph Public Corporationin March this year is unique system which can measure
impurities in semiconductors in order of by the orderof ppb and we got order Mini-cyclotron which canaccelerate Proton, Deuteron, He-3, and a Particles
from the Metal Materials Technical Research Instituteof the Agency of Science and Technology for study newmaterials of nuclear fusion reactors that canwithstand large quantities of neutrons with a highenergy of 14MeV.
At present, studies are active on neutron
radiography using Baby Cyclotron of energy 16MeV
producing neutrons by the reaction of Be (p, n). We
are conducting at our Muroran Plant the inspection ofpyrotechnical products for the H-1 rocket which theNational Space Development Agency is developing.
Experimental layout is shown in Fig. 1.
A Baby Cyclotron is used to accelerate proton up
to 16MeV with beam current of 50uA. These ions
impinge upon a Be target to produce copious quantities
of fast neutron. These fast neutrons are showed down
to the thermal energy region with a polyethylene
moderator surrounding the target. A portion of thethermalized neutrons are extracted from the target
area by a collimator constructed with polyethylene
boards.
Table 3 shows the typical results of the Baby
Cyclotron-based radiography system for ASTM
Indicators;
Photo 2 shows the differences of the radiographic
images for X-ray and neutron from Baby Cyclotron.

BeamEnergy(MeV)

ProtonBC1D510BC107
1DBC168
16BC1710
17Deuteron57810Beam
Current(uA)

Proton50505050

Deuteron

50505050

Extraction
Radius (em)

3030

37.5

42

Pole Gap.
Max. (em)
Min.

9.5
5.5

9.5
5.5

12713

Average
Magnetic
Field (T)

1.5

AVF
4 Sector
MagnetRF
Accelerating
System1.5(P)

Deflector

VacuumSystem1.8(D)

47&55 47&55 47

30

3030

Type
Voltage (V)Hot Cathode Penning Type-500 -500 -500 -500

Arc
Current (A)3TypeElectrostatic (DC)

Voltage (KV)

-50-50-50-50

Pressure(Torr)

10-6

10-6

10-6

10-6

Difuss ionPump( /sec.)

200

450

700

2,000333

Radioisotope Production Test with BC1710llc
13N

10150

213N(d,n)15 0

8.7

50

2,400mCi/10min

1502

18F

110

20Ne (d,a) 18F

8.7

50

600mCi/2h

18F2:

43.5&47

Plunger
Compensator

14N(p,alllc

Incident energy
(MeV)
16.0

Beam current(pAl50

3,600mC i /1 h

11 co212c (d, n)13N

8.7

50

1,200mCi/30min

13N2

16 0 (p,a)l3N

16.0501,400mCi/30min

13N- aqueoussolution. Reaction.

1.5(D)

Master Oscillator

Half life(min.)2D

Isotopes

1.4(P)1.5

2 X 45°

Accelerating
Voltage (KV) 30

IonSource

Table 2Dee
RF PoweredbyFrequency(MHz)
TuningRoughFine

7Yield (mCi)

Chemical form

We are, at present, developing several automated synthesis systems of precursor and organic compounds
labeled by short-lived radioisotopes.

32Baby Cyclotron

Moderator

Fig. 1

Schematic Diagram of Neutron Radiograph Using Cyclotron

Table 3 Typical Results of the Radiography System
for ASTM Indicatior
I

Type of cyclotronIParticle

i,-Proton'~----··---·-II-1-i 50
I--- - - - - - - - - - -Beam Current CuA)i Be

Target--~Collimator Length (mm)L------~-------~--l

~-

2~600

50

Collimator Ratio (LID)
Exposure Size (mm)

----

Gd

Neutron Flux at Object ( nI cm 2Is ec )3.5 X 105------

nly Ratio (nlmR)

3.3 X 105------------·-Cd Ratio

5

Therma 1 Neutron Content (C%);;: 50

Scattered Neutron Content (S%)~13

Epithermal Neutron Content (E%)

Neutron

432 X 356---------- ---- --Converter--

Photo 2Differences of the Radiographic Images
for X-ray and Neutron from Cyclotron

REFERENCE~4---~---

2.5

Low Energy Gamma-ray Content (Y%)~Sensitivity Level (R);;: 10FilmX-ray'

16

Energy (MeV)-----~·---iBC168

1.

I Kodak $R

33

E. Hiraoka et al. Ann. Report Radiation Centerof Osaka Prefecture Vol.23, '82