arXiv subjects

Elena Pasini

Publications and source records attributed to Elena Pasini.

2 recordsLinked to original sources

arXiv2025

Doping of a Borexino-like Liquid Scintillator with Tellurium-Diols

One promising approach for future neutrinoless double beta decay ($0\nu\beta\beta$) searches is the incorporation of candidate isotopes into liquid scintillator detectors. In this work, a sample of the high-performance 1,2,4-trimethylbenzene-based liquid scintillator used in the Borexino experiment was loaded with different concentrations of Te-diol compounds. To realize the loading, a modified water-free synthesis procedure in a non-acidic organic environment at room temperature was employed. The loaded scintillator mixtures were characterized with respect to their emission spectra, optical absorbance, light yield, and scintillation time profiles under $\alpha$ excitation. Within the experimental uncertainties, only comparatively small changes in the spectral emission shape and optical transmission were observed for Te-loadings up to 2\%. At the same time, a systematic reduction of the scintillation light yield with increasing Te concentration was measured. At 1\% Te-loading, an estimated light yield of approximately 8400\,photons/MeV$_{\mathrm{ee}}$ was obtained. Furthermore, the scintillation time profile measurements indicate systematically shorter effective decay time constants for increasing Te-loading, consistent with enhanced non-radiative de-excitation processes introduced by the Te-diol complexes. Overall, the results demonstrate that the investigated loading technique can be successfully applied to a pseudocumene-based liquid scintillator while preserving the principal scintillation characteristics of the system.

physics.ins-det↗

arXiv2024

Desynchronization Index: a New Connectivity Approach for Exploring Epileptogenic Networks

In drug-resistant epilepsy, Stereo-Electroencephalography (SEEG) monitoring is one of the most effective techniques to identify the Epileptogenic Zone (EZ), the fundamental prerequisite for epilepsy surgery. Despite recent technological advances, SEEG recordings remain difficult to interpret, and SEEG-guided surgery still achieves success rates below 70%. In this work, we develop a novel computational framework for SEEG analysis, with the ultimate aim of improving the accuracy in EZ definition. Specifically, we investigate the hypothesis that epileptogenic regions exhibit a tendency to behave independently and thus desynchronize from neighboring brain structures before seizure onset. To this end, we design the Desynchronization Index (DI), an algorithm that identifies the Epileptogenic Zone (EZ) as the subset of channels that disconnect from the SEEG network during the ictal transition. We evaluate the DI algorithm against Epileptogenicity Index (EI), one of the most common tools for EZ definition, on a clinical dataset of 20 patients, considering the channels that were thermocoagulated at the end of SEEG monitoring as the detection target. Our results show that DI overcomes EI in terms of area under the ROC curve (AUC=0.86 vs. AUC=0.83), while combining the two algorithms into a single framework leads to the best performance (AUC=0.88). Overall, the DI algorithm underscores anomalous connectivity patterns that are difficult to detect through visual inspection, improving the accuracy in the EZ definition and providing new insights into the dynamics of seizure generation.

eess.SP↗