Andrea Molinario | Searcharxiv

arXiv2026

High-precision measurement of $^{215}$Po half-life via delayed-coincidence analysis

We performed a high-precision study of the $^{215}$ Po $α$-decay using a LaBr$_3$ scintillating detector in a low-background environment. The $^{227}$Ac intrinsic contamination in the LaBr$_3$ crystal undergoes a decay chain, producing the intermediate pair of $^{219}$Rn$\rightarrow^{215}$Po$\rightarrow^{211}$Pb decays. The fast time response and good energy resolution of the detector allow for extracting the short half-life of $^{215}$Po from the time correlation of the two subsequent $α$-decays by using the delayed coincidence method. Thanks to high statistics and a comprehensive uncertainty assessment, we obtain the most precise half-life value to date of $^{215}$Po, corresponding to $1.77804\pm0.00091$(stat.)$\pm0.00067$(syst.) ms.

nucl-ex↗

arXiv2025

Characterization of a GAGG detector for neutron measurements in underground laboratories

In rare events experiments, such as those devoted to the direct search of dark matter, a precise knowledge of the environmental gamma and neutron backgrounds is crucial for reaching the design experiment sensitivity. The neutron component is often poorly known due to the lack of a scalable detector technology for the precise measurement of low-flux neutron spectra. Gd$_3$Al$_2$Ga$_3$O$_{12}$ (GAGG) is a newly developed, high-density scintillating crystal with a high gadolinium content, which could allow to exploit the high $(n,γ)$ cross section of $^{155}$Gd and $^{157}$Gd for neutron measurements in underground environments. GAGG crystals feature a high scintillation light yield, good timing performance, and the capability of particle identification via pulse-shape discrimination. In a low-background environment, the distinctive signature produced by neutron capture on gadolinium, namely a $β/γ$ cascade releasing up to 9 MeV of total energy, and the efficient particle identification provided by GAGG could yield a background-free neutron capture signal. In this work, we present the characterization of a first GAGG detector prototype in terms of particle discrimination performance, intrinsic radioactive contamination, and neutron response.

physics.ins-det↗