Speaker
Description
Tellurium isotopes are produced in nuclear reactors as fission products. Evaluation of neutron nuclear data of Tellurium isotopes was made recently [1]. On the other hand, $^{128}$Te is one of the candidate nuclides for neutrino-less double beta decay searches. Neutron-induced reactions of $^{128}$Te are important to evaluate background in measurement [2]. However, experimental data of the neutron capture cross section of $^{128}$Te at neutron energies below 1 MeV are old and have large uncertainties. Thus, in this work, new measurements were carried out to determine the capture cross section of $^{128}$Te using the time-of-flight (TOF) method in the keV energy region. Experiments were performed at the Laboratory for Zero Carbon Energy at the Tokyo Institute of Technology. Incident neutrons were generated through the $^7$Li(p,n)$^7$Be reaction by a pulsed proton beam from a Pelletron accelerator bombarding a lithium target. Experiments were carried out in the two different neutron energy regions: 15 – 100 keV and around 550 keV. The incident neutron energy spectrum was measured by the TOF method. Capture gamma-rays from the sample were detected with an anti-Compton NaI(Tl) spectrometer in the TOF experiments. The capture cross sections were obtained from the pulse height spectra by the pulse-height weighting technique. A comparison of the present results with past experimental data and evaluated cross sections was made. Gamma-ray spectra by unfolding the pulse height spectra with the detector response function were also derived.
References
1. K. Shibata, Journal of Nuclear Science and Technology, 52, 490-502 (2015).
2. W. Tornow et al., EPJ web of Conferences, 146, 09013 (2017).
