arXiv subjects

Bei-Zhen Hu

Publications and source records attributed to Bei-Zhen Hu.

4 recordsLinked to original sources

arXiv2025

The High Voltage Splitter board for the JUNO SPMT system

The Jiangmen Underground Neutrino Observatory (JUNO) in southern China is designed to study neutrinos from nuclear reactors and natural sources to address fundamental questions in neutrino physics. Achieving its goals requires continuous operation over a 20-year period. The small photomultiplier tube (small PMT or SPMT) system is a subsystem within the experiment composed of 25600 3-inch PMTs and their associated readout electronics. The High Voltage Splitter (HVS) is the first board on the readout chain of the SPMT system and services the PMTs by providing high voltage for biasing and by decoupling the generated physics signal from the high-voltage bias for readout, which is then fed to the front-end board. The necessity to handle high voltage, manage a large channel count, and operate stably for 20 years imposes significant constraints on the physical design of the HVS. This paper serves as a comprehensive documentation of the HVS board: its role in the SPMT readout system, the challenges in its design, performance and reliability metrics, and the methods employed for production and quality control.

physics.ins-det↗

arXiv2021

Mass production and characterization of 3-inch PMTs for the JUNO experiment

26,000 3-inch photomultiplier tubes (PMTs) have been produced for Jiangmen Underground Neutrino Observatory (JUNO) by the Hainan Zhanchuang Photonics Technology Co., Ltd (HZC) company in China and passed all acceptance tests with only 15 tubes rejected. The mass production began in 2018 and elapsed for about 2 years at a rate of $\sim$1,000~PMTs per month. The characterization of the PMTs was performed in the factory concurrently with production as a joint effort between HZC and JUNO. Fifteen performance parameters were tracked at different sampling rates, and novel working strategies were implemented to improve quality assurance. This constitutes the largest sample of 3-inch PMTs ever produced and studied in detail to date.

physics.ins-det↗

arXiv2015

Recent Results from Daya Bay Reactor Neutrino Experiment

The Daya Bay reactor neutrino experiment announced the discovery of a non-zero value of \sin^22θ_{13} with significance better than 5 σin 2012. The experiment is continuing to improve the precision of \sin^22θ_{13} and explore other physics topics. In this talk, I will show the current oscillation and mass-squared difference results which are based on the combined analysis of the measured rates and energy spectra of antineutrino events, an independent measurement of θ_{13} using IBD events where delayed neutrons are captured on hydrogens, and a search for light sterile neutrinos.

hep-ex↗

arXiv2014

New Results from the Daya Bay Reactor Neutrino Experiment

This presentation describes a precision result of the neutrino mixing parameter, $\sin^2 2θ_{13}$, and the first direct measurement of the antineutrino mass-squared difference $\sin^2(Δ_{ee}) \equiv \cos^2 θ_{12} \sin^2 Δ_{31} + \sin^2 θ_{12} \sin^2 Δ_{32}$ from the Daya Bay Reactor Neutrino Experiment. The above results are based on the six detector data-taking from 24 December 2011 to 28 July 2012. By using the observed antineutrino rate and the energy spectrum analysis, the results are $\sin^2 2θ_{13}=0.090^{+0.008}_{-0.009}$ and $| Δm^2_{ee}| = 2.59^{+0.19}_{-0.20} \cdot 10^{-3} $eV$^2$ with a $χ^2$/NDF of 162.7/153. The value of $| Δm^2_{ee}| $ is consistent with $| Δm^2_{μμ}|$ measured in muon neutrino beam experiments.

hep-ex↗