Speaker
Description
The TEXONO collaboration proposals in 2006 on reactor electron antineutrinos ($\bar{\nu}_e$) studies of coherent elastic neutrino-nucleus scattering ($\nu A_{el}$) using low-threshold Ge detectors stimulated extensive experimental activity [1], and subsequently demonstrated sub-keV Ge detector technology for neutrino and dark matter experiments with reliable performance in the sub-keV energy regime [2]. Intense low-energy fluxes of reactor $\bar{\nu}_{e}$
provide a powerful probe for precision studies of $\nu A_{el}$ in the fully coherent regime [3,4], as well as for searches for neutrino electromagnetic interactions [5]. The TEXONO collaboration reported the first constraint on the Standard Model (SM) $\nu A_{el}$ cross section from reactor $\bar{\nu}_e$ interactions in 2025 [6]. Building upon the first TEXONO limit based on a partial dataset, we will present updated results from the TEXONO at the Kuo-Sheng reactor Nenutrino Laboratory (KSNL) using the full dataset collected with electro-cooled $p$-type point-contact germanium ($p$PCGe) detectors with masses of 523 g and 1434 g. With a combined exposure of 404(813.7) kg$\cdot$days of Reactor ON(OFF) data and an electron-equivalent energy threshold of 200 eV, we obtain improved constraints on the $\nu A_{el}$ cross section, as well as on neutrino electromagnetic properties, particularly the neutrino magnetic moment via the neutrino-nucleus scattering channel. We will further discuss the current status and future prospects of the TEXONO experiment, with emphasis on background reduction strategies and systematic control of analysis thresholds for improved sensitivity in the reactor $\bar{\nu}_{e}$ regime.
References:
[1] H.T. Wong et al. (TEXONO Collaboration), J. Phys. Conf. Ser. 39, 266 (2006).
[2] A.K. Soma et al. (TEXONO Collaboration), Nucl. Instrum. Meth. A 836, 67 (2016).
[3] S. Kerman et al. (TEXONO Collaboration), Phys. Rev. D 93, 113006 (2016).
[4] V. Sharma et al. (TEXONO Collaboration), Phys. Rev. D 103, 092002 (2021).
[5] H.T. Wong et al. (TEXONO Collaboration), Phys. Rev. D 75, 012001 (2007).
[6] S. Karmakar et al. (TEXONO Collaboration), Phys. Rev. Lett. 134, 121802 (2025).