Speaker
Description
The rapid neutron capture (r-) process gained significant amounts of interest as a means of nucleosynthesis of elements in astrophysical environments. Consequently, there have been ongoing efforts to better understand it from the perspective of both, nuclear physics and astrophysics. From the standpoint of nuclear physics, such efforts include measurements of β-decay and delayed neutron emissions of the r-process elements for a more accurate input for the calculations in relation to its theoretical modelling [1].
Typically, β-γ spectroscopies are conducted with implantation detectors at fragmentation facilities such as the Silicon strip detectors at Radioactive Isotope Beam Factory (RIBF). However, these detectors lack fast timing response for the purpose of neutron time-of-flight measurements of the delayed neutron emissions. To address this limitation, a detector was developed with segmented Yttrium orthosilicate (YSO) scintillation crystal (Z ≈ 35, ρ ≈ 4.5 g/cm^3). The characteristics of the YSO detector enable an 80% correlation efficiency with a 3mm correlation radius between implant events and β-decay events [2].
The success of this detector encouraged the development of Lanthanum-enriched, segmented (Gd, La)2Si2O7:Ce (La-GPS) scintillation crystal (Z ≈ 51, ρ ≈ 5.2 g/cm^3) detector with the aim of achieving better correlation radius and higher energy resolution compared to the YSO, and faster timing response than Silicon strip detectors [3]. This presentation showcases the current status of the La-GPS scintillation crystal detector of (1.5 x 1.5)mm arranged into a 32 x 32 array in the x-y plane.
References
[1] M. R. Mumpower et al., “The impact of individual nuclear properties on r-process nucleosynthesis,” Prog. in Particle and Nucl. Phys., vol. 86, pp. 86-126, 2016.
[2] R. Yokoyama et al., “Segmented YSO Scintillation Detectors as a New β-Implant Detection Tool for Decay Spectroscopy in Fragmentation Facilities,” Nucl. Instrum. Methods Phys. Res. A, Accel. Spectrom. Detect. Assoc. Equip., vol. 937, pp. 93–97, 2019.
[3] A. Suzuki et al., “Fast and high-energy-resolution oxide scintillator: Ce-Doped (La,Gd)2Si2O7,” Appl. Phys. Express, vol. 5, no. 10, p. 102601, 2012.