OPERA（Oscillation Project with Emulsion tRacking Apparatus）是欧洲和亚洲之间的一个国际合作项目，旨在首次直接证明纯μ子中微子束中出现τ中微子，以验证大气中微子振荡的假设。欧洲第一个长基线中微子束（称为CNGS）是在CERN产生的，并被送往730公里外的格兰萨索地下实验室，OPERA探测器位于那里。自2006年以来，电子探测器部分已完全调试和运行。定期记录宇宙射线事件，在2007年秋季的最后一次运行中，在由非常精确的乳胶膜和铅板制成的目标元件中观察到了第一批中微子束事件。本文综述了该探测器的现状、束流性能、中微子事件分析的初步结果和展望。
英文摘要：
OPERA (Oscillation Project with Emulsion tRacking Apparatus)is an international collaboration between Europe and Asia, aiming to give the first direct proof of tau neutrino appearance in a pure muon neutrino beam, in order to validate the hypothesis for atmospheric neutrino oscillations. The first european long baseline neutrino beam called CNGS is produced at CERN and sent in the direction of the Gran Sasso underground laboratory 730 km away, where the OPERA detector is located. Since 2006 the electronic detector part is fully commissioned and running. Cosmic ray events have been recorded on a regular basis and the first neutrino beam events have been observed in the target elements made of very precise emulsion films and lead sheets during the last run in autumn 2007. This paper reviews the status of the detector, the beam performances, the first results from the neutrino event analysis and the prospects.
Bi-large patterns for the leptonic mixing matrix are confronted with current neutrino oscillation data. We analyse the status of these patterns and determine, through realistic simulations, the potential of upcoming long-baseline experiment DUNE in testing bi-large \emph{ansatze} and discriminating amongst them.
KEKB加速器和探测器，BELLE的状态，报告。1998年12月，3.5 GeV x 8 GeV正负电子对撞机和螺线管探测器BELLE的建造完成。自那时以来，一直在委托他们。1999年6月1日，BELLE探测器观测到了束流碰撞的第一个强子事件。到1999年8月4日，获得的最大亮度为3 x 10^32 cm^-2 sec^-1。KEKB的业务将在两个月的暑假后继续进行。
A number of short baseline neutrino oscillation experiments have observed an anomalous excess of neutrinos in the low energy range. This may hint towards the existence of additional neutrino mass splittings. If true, additional sterile (non-interacting) neutrino states above the current 3 neutrino model would be required. On the other hand, many parameters of the allowed space are limited by experiments that have seen no anomaly. We will introduce models which accommodate these additional neutrinos, and then discuss our work towards fitting these models to the available global high $Δm^{2}$ os…
The Deep Underground Neutrino Experiment (DUNE) is a dual-site experiment for long baseline neutrino oscillation studies, and for neutrino astrophysics and nucleon decay searches. DUNE will comprise four 10 kton fiducial liquid argon time-projection-chamber (LAr TPC) modules placed at the Sanford Underground Research Facility (South Dakota, USA). One of these modules will profit form the dual phase (DP) technology where the charge is extracted, amplified, and detected in gaseous argon above the liquid surface allowing a fine readout pitch, a low energy threshold, and good pattern reconstructio…
The Jiangmen Underground Neutrino Observatory (JUNO) is a 20 kton multi-purpose liquid scintillator detector currently being built in a dedicated underground laboratory in Jiangmen (PR China). Data-taking is expected to start in 2023. JUNO's main physics goal is the determination of the neutrino mass ordering using electron anti-neutrinos from two nuclear power plants at a baseline of about 53 km. JUNO aims for an unprecedented energy resolution of 3 $\%$ at 1 MeV for the central detector, which will allow determining the mass ordering with 3 $σ$ significance within six years of operation. Fur…
Light Sterile Neutrinos in Particle Physics: Experimental Status
大部分的中微子振荡结果都可以用三中微子模型来解释。然而，短基线振荡数据中的几个异常现象可以通过调用假设的第四中微子来解释，第四中微子与三个标准中微子的质量平方差超过0.1 eV $^2$。这种新的中微子，通常被称为无菌中微子，不会感受到标准模型的相互作用，而是与其他中微子混合。这样一种需要新物理学超越标准模型的设想，要么被排除，要么被新数据所证实。在简要回顾了反常振荡的结果之后，我们讨论了旨在澄清这种情况的世界范围内的实验方案。
The Short-Baseline Neutrino, or SBN, program consists of three liquid argon time projection chamber detectors located along the Booster Neutrino Beam at the Fermi National Accelerator Laboratory. Its main goals include searches for new physics - particularly eV-scale sterile neutrinos, detailed studies of neutrino-nucleus interactions at the GeV energy scale, and the advancement of the liquid argon detector technology that will also be used in the DUNE/LBNF long-baseline neutrino experiment in the next decade. Here we review these science goals and the current experimental status of SBN.
The Jiangmen Underground Neutrino Observatory (JUNO) is a 20 kton multi-purpose liquid scintillator detector currently being built in a dedicated underground laboratory in Jiangmen (PR China). JUNO' s main physics goal is to determine the neutrino mass ordering using electron anti-neutrinos from two nuclear power plants at a baseline of about 53 km. JUNO aims for an unprecedented energy resolution of 3% at 1 MeV for the central detector, with which the mass ordering can be measured with 3 - 4 $σ$ significance within six years of operation. Most neutrino oscillation parameters in the solar and …
