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RIKEN Accel. Próg. Rep. 24 (1990)

111*3-8. Dry Separation of Radioactive Nuclides from a Gold Target Irradiated with 135 MeV/u ¹⁴N lons

M. Iwamoto, S. Ambe, S.Y. Chen, Y. Ohkubo,

Y. Kobayashi, and F. Ambe

Fig. 1. Apparatus for dry separation. A, electric fumace; B, thermocouple; C, temperaturę controller; D, irradiated gold foil; E, cold finger; F, cooling water; G, rotary pump; H, Pirani gauge; I, quartz tubę; J, charcoal trap.

We started in this period a series of experiments on the preparation of multitracer Solutions from targets irradiated with heavy ions accelerated with RIKEN Ring Cyclotron.^ Solutions containing a large variety of radioactive nuclides are to be used in Chemical, geochemical, and biochemical investiga-tions. This report describes the separation of radioactive nuclides obtained from a gold target by heating under a reduced pressure.

A stack of gold foil was irradiated with a 135 MeV/u ¹⁴N-ion beam by using the falling bali irradi-ation system.²⁾ A piece of the gold foil was heated at 1,050°C (melting point of gold: 1,064°C) in a

Fig. 2.

OO

Gamma-ray spectrum of the nuclides dissolved from the cold finger into (1:1) hydrochloric acid.

500    1000    1500    2000    2500    3000    3500    4000

CHANNEL

ąuartz tubę under a pressure of about 1 Pa (Fig. 1). The nuclides evaporating from the foil were col-lected on a Pyrex cold finger cooled with water. The finger was successively immersed into (1:1) nitric acid and (1:1) hydrochloric acid Solutions. The dissolved radioactive nuclides were identified by y-ray spectrometry with a pure Ge detector. The spectrum of the hydrochloric acid solution is shown in Fig. 2.

y-Ray spectra were analyzed by the Computer program BOB developed by Baba et al.^3> The nuclides of following elements were found to have

been dissolved in acid Solutions:

(1:1) Nitric acid: Zn, As, Te, Tb, Re (1:1) Hydrochloric acid: Zn, As, Br, Te, I, Re A morę quantitative experiment is now in progress.

References

1)    S. Ambe, S.Y. Chen, Y. Ohkubo, Y. Kobayashi, M. Iwamoto, and F. Ambe: This Remort, p. 73.

2)    M. Yanokura, Y. Ohkubo, S. Ambe, M. Iwamoto, and F. Ambe: RIKEN Accel. Próg. Rep., 22, 150 (1988).

3)    H. Baba: JAERI-M, 7017.