高精度齿轮副侧隙自动测量技术研究

齿轮副侧隙是齿轮机械设计和齿轮啮合时的重要参数,为了提高齿轮副侧隙的测量精度,解决由于结构所限无法实现两个齿轮上同时安装圆光栅光电码盘作为角度传感器的齿轮副侧隙的测量,本文提出了一种基于光电角度测量模块的齿轮侧隙自动测量技术,在主动齿轮上安装微型光电角度测量模块,从动齿轮上安装光电编码器,来采集两齿轮的角度,并进行数据处理,软件控制,实现了齿轮副侧隙的自动测量。并给出了影响该自动检测系统的主要误差来源,进行了误差分析;最后通过试验给出了一种锥齿轮副侧隙的自动测量结果

Determination of the number of ψ(3686) events taken at BESIII

The number of ψ(3686) events collected by the BESIII detector during the 2021 run period is determined to be (2259.3±11.1)×106 by counting inclusive ψ(3686) hadronic events. The uncertainty is systematic and the statistical uncertainty is negligible. Meanwhile, the numbers of ψ(3686) events collected during the 2009 and 2012 run periods are updated to be (107.7±0.6)×106 and (345.4±2.6)×106, respectively. Both numbers are consistent with the previous measurements within one standard deviation. The total number of ψ(3686) events in the three data samples is (2712.4±14.3)×10^

Prediction of Energy Resolution in the JUNO Experiment

International audienceThis paper presents the energy resolution study in the JUNO experiment, incorporating the latest knowledge acquired during the detector construction phase. The determination of neutrino mass ordering in JUNO requires an exceptional energy resolution better than 3% at 1 MeV. To achieve this ambitious goal, significant efforts have been undertaken in the design and production of the key components of the JUNO detector. Various factors affecting the detection of inverse beta decay signals have an impact on the energy resolution, extending beyond the statistical fluctuations of the detected number of photons, such as the properties of liquid scintillator, performance of photomultiplier tubes, and the energy reconstruction algorithm. To account for these effects, a full JUNO simulation and reconstruction approach is employed. This enables the modeling of all relevant effects and the evaluation of associated inputs to accurately estimate the energy resolution. The study reveals an energy resolution of 2.95% at 1 MeV. Furthermore, the study assesses the contribution of major effects to the overall energy resolution budget. This analysis serves as a reference for interpreting future measurements of energy resolution during JUNO data taking. Moreover, it provides a guideline in comprehending the energy resolution characteristics of liquid scintillator-based detectors