III-3. Radiochemistry & Nuclear Chemistry

RIKEN Accel. Prog. Rep. 55 (2022)

RIKEN Accel. Prog. Rep. 55 (2022)

Production cross sections of 45 Ti via deuteron-induced reaction on45Sc†
Ts. Zolbadral,∗1,∗2 M. Aikawa,∗2,∗3,∗4 D. Ichinkhorloo,∗1,∗2 Kh. Tegshjargal,∗5 N. Erdene,∗5 Y. Komori,∗3H. Haba,∗3 S. Takács,∗6 F. Ditrói,∗6 and Z. Szücs∗645

†
∗1
∗2
∗3
∗4
∗5
∗6

Condensed from the article in Appl. Radiat. Isot. 168, 109448(2021)
Nuclear Research Center, National University of Mongolia
Graduate School of Biomedical Science and Engineering,
Hokkaido University
RIKEN Nishina Center
Faculty of Science, Hokkaido University
School of Engineering and Applied Sciences, National University of Mongolia
Institute for Nuclear Research (ATOMKI)

450
400

45Sc(d,2n)45Ti

Cross section (mb)

350
300
250
200
150

This work
Hermanne 2012TENDL-2019

100
50
005

10152025

Energy (MeV)

Fig. 1. Excitation function of the 45 Sc(d, 2n)45 Ti reaction.
2000
Physical Yield (MBq/μAh)

Ti (T1/2 = 184.8 min) is an appropriate positron
emitter isotope (Eβ + = 439 keV, Iβ + = 84.8%) forpositron emission tomography (PET). This radioisotope can be produced in the deuteron-induced reaction on a scandium-45 target at cyclotrons. However, the quality of experimental data on the cross sections of the 45 Sc(d, 2n)45 Ti reaction is not satisfactory.
Therefore, we aim to measure the cross sections of the45Sc(d, 2n)45 Ti reaction and to investigate a route for45
Ti production.
The stacked-foil activation technique and γ-ray spectrometry were adopted to determine the cross sections.
The stacked target included metallic foils of 45 Sc (thicknesses of 25.8 and 250 μm with a purity of 99.0%),27
Al (18.5 μm, 99.6%), and nat Ti (20.2 μm, 99.6%).
The target was irradiated for 30 min with a 24-MeV
deuteron beam from the RIKEN AVF cyclotron. The
incident beam energy was measured using the time-ofﬂight method. The energy degradation in the stacked
target was calculated using the SRIM code.1) The beam
intensity was measured using a Faraday cup and doublechecked with the nat Ti(d, x)48 V monitor reaction.2) By
comparing the monitor reaction, the measured intensity(180 ± 9 nA) was corrected by decreasing it by 2% to176 ± 9 nA. The γ-ray spectra of the irradiated foils weremeasured using a high-resolution and a high-purity germanium (HPGe) detector. The detector was calibratedusing a mixed γ-ray point source. In the measurements,
the dead time was kept below 7%.
Subsequently, the activation cross sections of 44, 45 Ti
and 44g, 44m, 46 Sc were determined. The measurementsof the 719.6-keV γ-ray (Iγ = 0.154%) from the 45 Ti
decay were used to derive the cross sections of the45Sc(d, 2n)45 Ti reaction. Figure 1 shows our measured
excitation function of the 45 Sc(d, 2n)45 Ti reaction incomparison with previous experimental data3) and thetheoretical estimation retrieved from TENDL-2019.4)
The derived excitation function is consistent with thedata reported by Hermanne et al.;3) however, it is lessscattered. The peak position of the TENDL-2019 datais slightly shifted to a lower energy.
The physical yield of 45 Ti was deduced from the measured excitation function and is shown in Fig. 2. The45Ti
1500

This work
Dmitriev+(1982)

1000

500005101520Energy (MeV)

Fig. 2. Physical yield of 45 Ti.

present yield curve of 45 Ti is slightly higher than the experimental data obtained by Dmitriev et al.5) at 22 MeV.
44
Ti is the only one co-produced radioactive isotope oftitanium in our experiment and can be formed by (d, 3n)reaction on 45 Sc above 15 MeV. Therefore, isotopicallypure 45 Ti production is possible in (d, 2n) reaction on
45
Sc in an energy range of 8–15 MeV.
This work is supported by JSPS KAKENHI Grant
Number 17K07004 and partly supported by the research program between the JSPS and HAS Contract No: JPJSBP120193808 and NKM-43/2019. Ts.Z
was granted a scholarship by the M-JEED project(Mongolian-Japan Engineering Education Development
Program, J11B16).
References
1) J. F. Ziegler et al., Nucl. Instrum. Methods Phys. Res. B
268, 1818 (2010).
2) A. Hermanne et al., Nucl. Data Sheets 148, 338 (2018).
3) A. Hermanne et al., Nucl. Instrum. Methods Phys. Res.
B 270, 106 (2012).
4) A. J. Koning et al., Nucl. Data Sheets 155, 1 (2019).
5) P. P. Dmitriev et al., INDC(CCP)-210, 1 (1983).

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