大仓鼠背毛和腹毛红外光谱差异

为了探究通过被毛红外光谱特征进行啮齿目（Rodentia）动物种类鉴定的可行性，使用傅里叶红外光谱（FT-IR）及其二阶导数谱（SD-IR）对大仓鼠（Tscherskia triton）背毛和腹毛进行检测与分析。结果表明：大仓鼠的背毛和腹毛均能反映出该物种的特征性成分，背毛和腹毛的红外图谱基本一致，均在621、679、782、846、1562、1637 cm-1附近有明显的吸收峰形成，在3415、3470 cm-1均有明显吸收峰出现，形成W形图谱；二阶导数谱也基本相同，均在683、703、776、786、854 cm-1有明显的吸收峰。尽管存在这些相似性，但红外图谱和二阶导数谱也能明显地反映出背毛和腹毛的特定差异，腹毛吸收峰的峰面积和峰强明显比背毛的大。在红外图谱中，845~848 cm-1和1426~1439 cm-1处，二者出峰位置均有明显差异；在700~727 cm-1，二者的峰形有较大差异。二阶导数谱中，在621~645 cm-1处，腹毛形成2个W形图谱，背毛形成1个W形图谱；在707~718 cm-1处，背毛形成1个W形图谱，腹毛形成1个明显的单峰；在818~835 cm-1处，腹毛形成1个M形图谱，背毛形成2个M形图谱；背毛和腹毛分别在652~655、650~655 cm-1形成1个单峰；背毛在700 cm-1形成1个单峰，腹毛未形成明显的峰。研究认为，大仓鼠背毛和腹毛的红外光谱特征基本一致，但二阶导数谱能更好地反映出二者的差异。故红外光谱可用于大仓鼠不同部位被毛的识别与鉴定工作

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

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel

JUNO sensitivity on proton decay p → ν K + searches*

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the $p\to \bar{\nu} K^+$ mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar{\nu} K^+$ is 36.9% ± 4.9% with a background level of $0.2\pm 0.05({\rm syst})\pm$$0.2({\rm stat})$ events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is $9.6 \times 10^{33}$ years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies

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^