Speakers
Description
Studies of neutron-induced reactions are of considerable significance, both for their importance to basic research in nuclear physics and for practical applications in nuclear technology, medicine and industry. Thallium is widely used in electronics, pharmaceuticals, fiber optics, infrared detectors and nuclear medicine. However, little information is available in literature for neutron induced reactions on Tl isotopes, with many discrepancies among the existing experimental data, especially in the energy region above ~14 MeV.
The aim of the present work was to study the cross-section of the (n,2n) reaction on 203Tl, by irradiating a natural TlCl pellet target with monoenergetic neutron beams at 16.9 and 18.9 MeV. The cross section of the 203Tl(n,2n)202Tl reaction was measured implementing the activation method, with respect to the 197Au(n,2n)196Au and 27Al(n,α)24Na reference reactions. The monoenergetic neutron beam was generated at the 5.5 MV Tandem accelerator of NCSR Demokritos, using the 3H(d, n)4He reaction. The target and reference foil assembly was placed at approximately 1.5 cm from the tritium target, thus limiting the angular acceptance to ± 23.5°, where the produced neutrons are practically isotropic and monoenergetic. The fluctuation of the neutron beam flux was monitored with a BF3 detector located 3 m from the neutron source. After the irradiation, the induced activity of the samples was measured with a HPGe detector of 80% efficiency, which was properly shielded with a lead block to reduce the contribution of natural radioactivity. Monte Carlo simulations using the MCNP code have been performed to take into account the gamma-ray self-absorption within the samples as well as the attenuation of the neutron flux through the target and reference foils.
Theoretical calculations with the EMPIRE code will also be presented, using the same parametrisation implemented in the theoretical study of Ir [1] and Au [2] nuclei, in an attempt to study the systematics and find a suitable statistical model for the description of all the experimental results in this mass region.
- A. Kalamara et al., Phys. Rev. C 98, 034607 (2018).
- A. Kalamara et al., Phys. Rev. C 97, 034615 (2018).