III-3. Radiochemistry & Nuclear Chemistry

RIKEN Accel. Prog. Rep. 54 (2021)

RIKEN Accel. Prog. Rep. 54 (2021)

Production cross sections of nat Er(d, x)171 Er reactions on naturalerbium†
M. U. Khandaker∗1,∗2 and H. Haba∗2
The nuclear reaction cross-sections play a key role inoptimization of production parameters for radionuclideof interest via the use of particle accelerators. In thisstudy, the production cross-sections of nat Er(d, x)171 Er
reaction has been measured by using stacked foil
activation technique combined with HPGe gammaray spectrometry. 171 Er (T1/2 = 7.516 h; Eγ =308.291 keV, Iγ = 64%) finds remarkable applications
for the development and evaluation of pharmaceutical drug delivery systems via the well-known gamma
scintigraphic technique.1) The measured cross-sectionsfor 171 Er also find great significance as a short-lived
parent for producing medically important long-lived
daughter 171 Tm (T1/2 = 1.92 y) via the 170 Er(d, p)
171
Er → 171 Tm process. Note that considering thecommon drawbacks of (n, γ) production route, severalauthors2) studied the production possibility of erbium
radionuclides via light-charged particles-induced reactions on several targets. However, since a search ofliterature shows that the status of deuteron-induced
reaction cross-sections on erbium is not satisfactory,
further study on such processes may find great significance in various respect.
Under this circumstance, the production crosssections of nat Er(d, x)171 Er nuclear reaction has beenmeasured from threshold up to 23.06 MeV by using theAVF cyclotron of the RIKEN RI Beam Factory, Wako,
Japan. Details on the irradiation technique, radioac-Fig. 2. Thick target integral yields (physical) for 163, 170 Tmand 171 Er radionuclides.

tivity determination, and data evaluation procedures
are available in Ref. 3). Owing to the space limitation of this report, we present only the nat Er(d, x)171 Er
cross sections and the deduced yield in Figs. 1 and 2,respectively. Measured cross sections with an overall
uncertainty are listed in Ref. 3). The cross-sections
were normalized by using the nat Ti(d, x)48 V monitor
cross sections recommended by IAEA. Measured data
were critically compared with the available literature
data, and an overall good agreement was found. However, only partial agreements were obtained with thedata extracted from the tendl-2017 library and empire-3.2.2 code.
Realizing the applications of measured radionuclides
including nat Er(d, x)171 Er → 171 Tm in medical andother fields, it is hope that the measured data could
play an important role in enrichment of the crosssection database that are useful for applications in
the medical, industrial and accelerator technologies.
The large discrepancy for the 170 Er(d, p)171 Er (Ethr =0.0 MeV) reaction between the model code and themeasurement is an important clue to modify the modelcode.
References

Fig. 1. Excitation function of the nat Er(d, x)171 Er reaction.
†∗1∗2Condensed from Nucl. Instrum. Methods Phys. Res. B 470,1 (2020)
Centre for Biomedical Physics, Sunway University
RIKEN Nishina Center

1) A. F. Parr, R. M. Beihn et al., Pharm. Res. 4, 486(1987).
2) H. Uusijarvi, P. Bernhardt et al., J. Nucl. Med. 47, 807(2006).
3) M. U. Khandaker, H. Haba et al., Nucl. Instrum. Methods Phys. Res. B 470, 1 (2020).

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