SearcharxivSearch

arXiv · 2510.05868

Unified framework for precise background modeling to enhance rare event detection at the Kuo-Sheng nuclear reactor laboratory

Abstract

A comprehensive GEANT4 simulation framework was developed to model the background of the TEXONO experiment, including contributions from radioactive isotopes in detector components and the surrounding environment. The HPGe detector front-end electronics (pre-amplifier) were modeled with trace amounts of naturally occurring radionuclides 238U, 232Th, and 235U from manufacturing materials. Results show that the 238U and 232Th decay chains dominate the background below 400 keV, each contributing O(1) counts kg^-1 keV^-1 day^-1. Trace impurities were also introduced into the anti-Compton veto (ACV) detectors to represent realistic materials: 40K in the NaI(Tl) crystal and 137Cs in the CsI(Tl) detector. Simulations identified measurable background contributions from both isotopes, with the residual spectrum dominated by 40K gamma-rays and smaller contributions from 137Cs. The 40K background rate is about 0.1 counts kg^-1 keV^-1 day^-1, nearly 10 times larger than that from 137Cs below 400 keV. Environmental radioactivity was modeled using 60Co, 54Mn, and 135Xe distributed in the air gap between the copper end-cap and the NaI(Tl) ACV detector, representing airborne and surface contamination. These sources contribute minor background components below 100 keV, at levels of about 10^-2, 10^-2, and 0.1 counts kg^-1 keV^-1 day^-1 for 135Xe, 54Mn, and 60Co, respectively. Comparison of simulated and measured spectra shows good overall agreement, with only minor deviations at specific gamma-lines, validating the background model and demonstrating the robustness of the simulation framework for detector and shielding design.

Explore related subjects

Keep this discovery

BibTeXRIS

Subhasis Parhi, Lakhwinder Singh, Manoj Kumar Singh, Henry Tsz-King Wong, Venktesh Singh. 2025-10-07. Unified framework for precise background modeling to enhance rare event detection at the Kuo-Sheng nuclear reactor laboratory. https://doi.org/10.1088/1748-0221%2F21%2F05%2Fp05016

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

Production of Light Nuclei and Hypernuclei in Heavy-Ion Collisions

We review recent STAR and ALICE measurements of light-nucleus and hypernucleus yields, femtoscopic correlations, and collective flow presented at SQM 2026. Statistical-hadronization calculations provide a useful baseline for integrated yields but do not simultaneously describe all measured light-nucleus ratios across collision energies and system sizes. For bound states with mass number $A<4$, current coalescence calculations provide a broadly consistent description of yields, femtoscopic correlations, and collective flow, although the quantitative hypertriton comparison depends on the assumed few-body wave function. The suppressed production of resonant $^{4}$Li relative to compact $^{4}$He indicates an effect of nuclear structure and late-stage dynamics. However, the quantitative model comparison also depends on the treatment of feed-down from unstable states. In high-multiplicity $p$+$p$ collisions, pion-deuteron femtoscopy further indicates that most observed (anti)deuterons are formed through nucleon fusion after strong decays of short-lived resonances. Taken together, these measurements show that production chronology and internal nuclear structure leave measurable imprints on the physics observables.

hep-ex

Search for the process $e^+e^-\to f_1(1285)$ at the SND detector

In the experiment with the SND detector at the VEPP-2000 $e^+e^-$ collider, a search is performed for the direct production of the $C$-even $f_1(1285)$ resonance in $e^+e^-$ collisions. The analysis is based on data with an integrated luminosity of about 200 pb$^{-1}$, accumulated in the center-of-mass energy range of 1.14--1.46 GeV, of which about 72 pb$^{-1}$ were recorded near the maximum of the $f_1(1285)$ resonance. The $f_1(1285)$ production cross section at the resonance maximum $\sigma(e^+e^-\to f_1)=(31\pm 13\pm 2)$ pb and the branching fraction $B(f_1(1285)\to e^+e^-)=(3.5\pm 1.4\pm 0.3)\times 10^{-9}$ have been measured. The significance of the observation of the $e^+e^-\to f_1(1285)$ process is $2.5\sigma$. Since the significance is low, we also present the upper limits at the 90% confidence level: $\sigma(e^+e^-\to f_1)<48\mbox{ pb}$ and $B(f_1(1285)\to e^+e^-)<5.4\times 10^{-9}$.

hep-ex

Projected Sensitivity to Slow Muonphilic Dark Matter with Accelerator Muon Beams

The nature of dark matter (DM) remains one of the most enduring open questions in modern physics, and muonphilic DM has emerged as a promising scenario that complements traditional DM candidates. Following the recently established cosmic-ray muon scattering approach, we investigate the sensitivity for probing slow muonphilic DM with accelerator muon beams. A Geant4-based simulation framework is developed, incorporating the detector geometry from the PKMu muon tomography system and a dedicated elastic $\mu$-DM scattering process. The projected sensitivity is found to be largely insensitive to both the beam energy and the transverse beam size when the beam is fully contained within the detector acceptance. For a benchmark beam intensity of $10^5/\rm{s}$, the simulated pure-muon beam surpasses the existing cosmic-ray limit of $1.61\times10^{-17}$ cm$^2$ at $m_{\rm DM}=1$ GeV within approximately 11 seconds. A realistic muon beam phase-space distribution based on simulations for the High Intensity heavy-ion Accelerator Facility (HIAF) is also implemented, yielding projected limits that improve upon the cosmic-ray results by nearly two orders of magnitude in a one-day exposure. These results demonstrate that a beam-muon scattering experiment offers a robust and promising route toward significantly improved sensitivity to slow muonphilic DM.

hep-ex