位于欧洲核子研究中心(CERN)的 LHCb 实验通过对底强子和粲强子的精确测量,针对CP破坏和强子谱学等前沿课题进行研究,理解标准模型、探索新物理。本报告将概述LHCb前沿课题,重点介绍 LHCb 实验在重味强子CP破坏及谱学等研究领域的前沿进展。
I will presents a combination of searches for Higgs boson pair (HH) production performed by the ATLAS and CMS Collaborations using Run 2 data.
TRIDENT (海铃) is a next-generation deep-sea neutrino telescope currently under development in the South China Sea, aiming to investigate the high-energy Universe through the observation of astrophysical neutrinos. By instrumenting a multi-cubic-kilometre volume of seawater with advanced optical sensors with high photon detection efficiency and precise timing capabilities, TRIDENT is designed to...
环形正负电子对撞机(FCC-ee 与 CEPC)已被国际高能物理界提议作为 Higgs 玻色子与 Z 玻色子研究的下一代装置。在国际大科学装置(ILD)探测器概念及同类设计中,主径迹探测器均采用高精度时间投影室(TPC)作为核心方案,其空间分辨率约为 100 μm,工作于 3.0 T 超导螺线管磁场中。TPC 需实现动量分辨率达 10⁻⁴ (GeV/c)⁻¹,且粒子鉴别(PID)分辨率需优于 3%。TPC 技术在 Higgs 运行模式下性能优异,但在高亮度 Z-pole 运行条件下面临显著技术挑战,其可行性及应对策略需深入模拟和实验研究。
本报告将介绍高精度 TPC 作为 e⁺e⁻ 对撞机主径迹探测器的可行性及最新研究进展。基于束流本底模拟数据,系统研究了离子诱导空间电荷效应,深入评估了 TPC 技术挑战及潜在解决方案,特别针对低亮度 Z-pole...
高能宇宙线核子与大气分子碰撞,形成广延大气簇射过程,大气簇射的末态粒子可以提供核-核碰撞的强作用过程的关键信息。我国高山宇宙线观测站LHAASO,可以在甚高能宇宙线大气簇射发展最大处,精确测量大气簇射产生的电磁粒子和缪子,为研究核-核碰撞的强作用过程提供了可能。本报告将基于LHAASO实验的数据,研究大气簇射次级粒子中缪子丰度和涨落、缪子的横向分布行为,并通过簇射缪子丰度随天顶角的变化,研究簇射缪子丰度的衰减行为;通过与不同强作用模型的模拟结果进行比较,对强作用模型进行检验;我们还将展示利用大气簇射进行夸克胶子等离子体研究的可行性的初步结果。
This talk is an overview of recent Belle II results on measuring the CKM matrix elements, LFU, CPV, and hadron spectroscopy.
我国在先进大型精密硅基磁谱仪系统自主研制方面缺乏系统性经验和关键技术综合能力。硅径迹探测器作为精密粒子磁谱仪的核心,其研制涵盖探测器设计、高性能传感器、先进电子学、轻质高强度支撑结构、高效冷却系统及数据采集系统。项目团队以大工程建制为组织体系,围绕硅径迹探测器关键技术,以下一代磁谱仪实验为主线,系统推进高精度半导体径迹探测器及相关关键技术研发。通过结构设计、物理机理研究、工艺优化及性能表征,研制国际首款兼具优于40 ps时间分辨和优于10...
We will report on the recent progress of the RECODE experiment and discuss its prospects for probing BSM physics.
Medium modification of jet substructure in the hot and dense nuclear matter has garnered significant interest from the heavy-ion physics community in recent years. Measurements of inclusive jets show an angular narrowing in nucleus-nucleus collisions, while recent CMS results for photon-tagged jets ($\gamma$+jets) suggest evidence of broadening. In this study, we conduct a theoretical analysis...
In this talk, I will present the latest results on the search for Higgs boson decaying into dimuon final state as well as the search for Higgs boson pair production using bb𝜏𝜏 final state at the ATLAS experiment. In addition, I will present the corresponding HL-LHC projection results based on the latest analysis strategy.
宇宙大爆炸约1秒后,中微子便从高温致密的等离子体中退耦,形成了宇宙中微子背景。随着宇宙膨胀,这些遗迹中微子温度已冷却至约1.95 K。由于中微子只发生弱相互作用,其直接探测一直极为困难。现有最受期待的背景中微子探测方案是PTOLEMY实验,但其探测灵敏度受到量子不确定性关系带来的本底限制。在这种情况下,相干散射方案重新受到关注。背景中微子的动量极低,使其能够与厘米尺度的宏观靶物质发生相干散射,使散射截面获得阿伏伽德罗常数量级的增强。然而,这一机制也带来了新的问题,反冲动量会平均分散到大量原子上,使得观测变得不可行。本报告将介绍一种新的背景中微子诱导的过程,利用宇宙背景中微子与低温原子或分子系统的相干散射,诱导其产生参量荧光效应(ν_i + M → ν_j + γ +...
During the High Luminosity phase of LHC, up to 140 - 200 proton-proton collisions per bunch crossing will bring severe challenges for event reconstruction. To mitigate pileup effects, an extended upgrade program of the CMS experiment is expected. Among these, a new timing layer, the MIP Timing Detector (MTD), will be integrated between the tracker and the calorimeters. With a time resolution...
A search for di-Higgs boson production in the HH→bbγγ channel is presented using proton-proton collision data collected by the CMS experiment. Combining the large H→bb branching fraction with the excellent diphoton mass resolution of CMS, this channel provides strong sensitivity to the Higgs self-coupling and potential beyond-Standard-Model signatures. The analysis strategy and its sensitivity...
江门中微子实验(JUNO)是一个位于中国江门的多物理目标的中微子实验。JUNO的主要目标是通过观测反应堆中微子来测定中微子质量顺序,并高精度测量中微子振荡参数,包括sin$\theta_{12}$、$\Delta m^{2}_{21}$ 和 $\Delta m^{2}_{31}$。
JUNO的探测器由一个有效质量为2万吨的液体闪烁体中心探测器、一个兼作缪子反符合系统及放射性屏蔽层的水池,以及外层的塑料闪烁体顶部径迹探测器组成。经过十余年的探测器建设和八个月的联合调试阶段,JUNO于2025年8月底开始物理数据采集,并于11月发布了首批物理结果。
本报告将重点介绍基于JUNO运行数月后的反应堆中微子数据的振荡分析结果。
The BESIII experiment has collected 20.3 fb-1 and 7.33 fb-1 of e+e- collision data at center-of-mass energies of 3.773 GeV and 4.128-4.226 GeV, respectively. This presentation will provide an overview of recent studies using (semi)-leptonic D decays at BESIII. We will present the first experimental investigation of Ds*+ to l+ nu decays, along with improved measurements of the CKM matrix...
The 2HDM+S is the singlet extension of the two-Higgs-doublet model (2HDM). The singlet field and its mixing with the 2HDM Higgs sector lead to new contributions to the electroweak precision observables, in particular, the oblique parameters, as well as the direct searches of BSM Higgs In this work we performed a systematic investigation of the impacts of each mixing angle on the oblique...
The BESIII experiment has collected 10 billion J/ψ events and 2.7 billion ψ(3686) events. The huge charmonium data samples allow us to search for rare decay processes allowed in the standard model and new physics beyond the standard model. In this talk, we report the search for charged lepton flavor violation process ψ(3686)→eμ, charmonium weak decay processes J/ψ→γD0, J/ψ→D0μ+μ-, J/ψ→D0K0*,...
碳化硅(SiC)具有宽禁带、高原子位移阈能、高导热率、高载流子饱和漂移速度、高临界击穿电场等特性,碳化硅探测器具有抗辐照、常温或高温下稳定运行、快响应时间等优势,可以应用在高能物理、核物理、空间探测等领域。首先,我们研制出探测面2mm×2mm、时间分辨为40ps的4H-SiC PIN探测器。能量为2.896 GeV的Ta离子辐照后,该探测器的时间分辨和电荷收集效率分别为45ps和97.4%。其次,为实现探测器在低能软X射线、低能α粒子、紫外光探测等领域的应用,在传统4H-SiC探测器时间分辨为100ps的基础上,利用石墨烯降低碳化硅探测器的死区效应,研制出电荷收集均匀稳定、时间分辨为58.0ps的石墨烯/4H-SiC探测器。在能量为160 keV、剂量为1...
中国锦屏地下实验室的垂直埋深为2400米,是进行低本底中微子实验的理想场所。锦屏中微子实验(JNE)团队将建造一个具有500立方米靶体积的中微子探测器,中心的亚克力容器直径10米,由双向绳网系统吊装在探测器屏蔽水箱中心,允许中微子探测靶材料的密度比屏蔽水高或低20%,安装新型的8英寸微通道板光电倍增管、快速模数转换器读出系统。JNE...
中微子振荡实验已确认中微子具有非零质量并存在轻子味混合,然而中微子质量的起源、轻子混合的结构以及CP破坏的来源,至今仍是粒子物理中悬而未决的核心问题。味对称性被广泛视作理解轻子味结构的关键理论工具,其基本思想是引入作用在不同代费米子之间的对称性,约束轻子质量矩阵,从而解释观测到的混合参数。本报告将首先回顾当前实验给出的轻子混合参数。随后,梳理味对称性理论的发展脉络,重点讨论非阿贝尔分立味对称群在解释轻子混合图像中的作用。进而,阐述广义CP对称性与味对称性相结合如何有效增强理论预言能力。最后,报告将介绍近年来兴起的模对称性框架,并结合当前与未来中微子振荡实验的精密测量,展望味对称性理论在揭示中微子质量起源、轻子CP破坏乃至统一味问题等方面的发展前景。
核子自旋结构是理解强相互作用非微扰动力学的重要问题之一。本报告将介绍我们利用格点 QCD对核子部分子分布函数及其自旋相关物理量的第一性原理研究。首先,我们在大动量有效理论框架下计算核子的非极化和螺旋度 PDF,并重点讨论极化比值 $\Delta q/q$ 以及纵向自旋不对称性 $A_1^p$、$A_1^n$。这些比值能够直接刻画不同味道夸克在给定动量分数下与核子自旋同向或反向的程度,是连接格点 QCD、整体拟合和极化深度非弹散射实验的重要物理量。其次,我将介绍我们对夸克TMDPDFs的计算,包括非极化分布、Boer-Mulders 函数、螺旋度分布和 worm-gear 分布等。这些结果为从一维动量结构到三维横动量依赖结构理解核子自旋提供了新的第一性原理信息,并为未来 JLab 和 EIC 等极化实验提供第一性原理的理论参考。
江门中微子实验(JUNO)是当前国际上重要的大型中微子实验之一,旨在通过高精度探测反应堆中微子事例,开展中微子振荡及相关物理问题的研究。对于大型液体闪烁体探测器而言,准确理解探测器响应、建立稳定可靠的能量标度,并实现高精度能量重建,是保证实验物理结果可靠性的关键基础。
本报告将围绕JUNO探测器刻度和能量重建相关工作展开介绍。报告内容包括探测器刻度体系的总体思路、刻度数据在探测器响应研究中的作用,以及能量重建方法在数据处理和物理分析中的应用。通过综合利用刻度数据、探测器响应模型和重建算法,可以逐步建立对探测器空间响应、时间响应和能量响应的整体理解,并为后续物理分析提供必要的输入和约束。
报告还将简要讨论能量重建性能评估、系统不确定性控制以及相关工作对JUNO核心物理目标的支撑作用。上述研究对于提升JUNO实验的数据质量、完善分析流程和实现高精度中微子测量具有重要意义。
Sphaleron dynamics in the Standard Model at high-energy particle collisions remains experimentally unobserved, with theoretical predictions hindered by its nonperturbative real-time nature. In this work, we investigate a quantum simulation approach to this challenge. Taking the 1+1D $O(3)$ nonlinear $\sigma$-model as a protocol towards studying dynamics of the sphaleron in electroweak theory,...
The existence of three distinct neutrino flavors, with oscillations between them, has been established by several experiments over the past decades. However, anomalies observed in experiments such as LSND, MiniBooNE, and gallium source experiments have motivated the hypothesis of an additional neutrino state—a sterile neutrino—that does not interact directly with matter yet oscillates with the...
本报告将以LHC上的 toponium 和 BES上的 psi(2S)->tau tau为例,介绍 t tbar 之间,以及 tau+ tau- 之间的自旋纠缠相关理论预言和实验测量方案。
Exploring the QCD phase transition is one of the most important goals in relativistic heavy-ion collisions. The Beam Energy Scan Program at RHIC has revealed a preliminary non-monotonic behavior of net-proton multiplicity fluctuations with increasing collision energy [1], which is consistent with theoretical predictions [2].
However, the quark-gluon plasma created in relativistic heavy-ion...
A study of angular correlations inside jets induced by gluon polarization is performed using proton-proton collisions at a center-of-mass energy of \sqrt{s} = 13.6 TeV. The data correspond to an integrated luminosity of 34.7 fb^{-1}, collected in 2022 with the CMS detector at the LHC. The details of the parton shower are investigated using jets reconstructed with the anti-k_\mathrm{T}...
The ordering of neutrino masses remains a key unknown in particle physics and cosmology. While upcoming oscillation experiments are expected to determine the mass ordering at low energies, it is important to explore complementary probes that access the underlying mechanism of neutrino mass generation. In this work, we show that future high-energy electron–positron colliders can provide...
The High Luminosity LHC (HL-LHC) phase, scheduled to start in 2030 and deliver 3000 fb⁻¹ in 10 years, will offer unique potential for precision measurements and searches for rare processes. However, it will also pose significant challenges for the detectors due to extremely high radiation levels and the large number of simultaneous interactions per bunch crossing (up to 200). To mitigate the...
The Beijing Spectrometer III (BESIII) experiment at the Beijing Electron–Positron Collider II (BEPCII) carries out precision measurements in tau–charm physics, hadron spectroscopy, nucleon form factors, and corrections to the muon anomalous magnetic moment.
Initial State Radiation (ISR) return method provides a unique path to access lower center–of–mass energies without interrupting...
In this talk, I will discuss coherence effects in non-standard interactions and astrophysical environments. For nonstandard tensor interactions, contributions traditionally considered spin-suppressed can instead receive coherent enhancement within a complete nuclear response framework, leading to cross sections orders of magnitude larger than conventional expectations. In astrophysics,...
Compared with SMEFT, HEFT is applicable to a broader class of spontaneous symmetry breaking scenarios. However, its non-linear structure and the fact that HEFT is formulated directly in the broken phase make UV-HEFT matching more challenging. In the first part of this talk, we present a non-linear framework for ultraviolet theories that is particularly suitable for implementing UV-HEFT...
切伦科夫探测器在对撞机实验中是实现高精度粒子鉴别的重要技术手段。我国提出的环形正负电子对撞机(CEPC)已完成探测器技术设计报告,为进一步提升端盖区域π、K、P粒子鉴别能力,突破高动量区间鉴别瓶颈,扩大立体角覆盖范围,拟在端盖区域增设专用切伦科夫探测器。本报告主要内容包括对国际上同类型切伦科夫探测器的调研,CEPC端盖切伦科夫探测器的概念设计,探测器的初步模拟,以及关键技术(切伦科夫辐射体,光子探测)的初步研究等方面的内容,希望与国内同行进行交流和合作。
Fragmentation Function (FF) plays a crucial role in describing the hadronization process. We report the measurements of normalized differential cross sections of inclusive pi0 and Ks production as a function of hadron momentum at six energy points with q^2 transfer from 5 to 13 GeV^2 at BESIII. The results with a relative hadron energy coverage from 0.1 to 0.9 significantly deviate from...
Soft unclustered energy patterns (SUEPs) are characterized by high-multiplicity, isotropic distributions of low-momentum particles. The search for SUEPs containing muons in the final state is presented using 140 fb^−1 of proton–proton collision data collected by the ATLAS detector at the Large Hadron Collider during 2015–2018. The analysis targets SUEP signatures produced via gluon–gluon...
In the search for the conjectured QCD critical point, higher-order cumulants of conserved quantities have been proposed as sensitive observables and have been studied extensively, both experimentally and theoretically. Recently, a precision measurement [1] of net-proton number fluctuations by the STAR Collaboration was published, focusing on high-statistics Au+Au collision datasets at...
To maintain the performance of muon triggering and reconstruction under high background at HL-LHC, the forward part of the muon spectrometer of the CMS experiment will be upgraded with Gas Electron Multipliers (GEM). A first GEM station (GE1/1), covering about 50m2, was installed during the Long Shutdown 2 (LS2, 2019–2021). Three GE2/1 chambers have additionally been installed during the...
CICENNS(CsI(Na) detector for Coherent Elastic Neutrino-Nucleus Scattering)实验是由中山大学牵头、依托中国散裂中子源(CSNS)建设的中微子—原子核相干弹性散射(CEvNS)实验。CEvNS作为标准模型下低能中微子的主要相互作用过程,不仅可用于验证标准模型预言,还为研究原子核中子分布及非标准中微子相互作用等新物理提供独特途径。CICENNS实验计划建设总质量为300 kg的CsI(Na)闪烁晶体探测器阵列,利用散裂中子源产生的高通量脉冲中微子,对CEvNS过程进行高精度测量。本报告将介绍中国散裂中子源上CICENNS实验计划和最新进展。
This report summarizes the current experimental landscape, covering both conventional WIMP searches and the explorations of the broader Dark Sector. This will also discuss the critical role of theory benchmark model preparation — such as the 2HDM+a framework in guiding Run 3 analyses and interpreting results. This report highlights the evolving strategies to probe the dark matter on colliders.
The dominance of matter over antimatter in the universe has consistently driven the pursuit of new physics beyond the Standard Model that violates charge-parity (CP) symmetry. The BESIII experiment has collected 10 billion J/ψ events and 2.7 billion ψ(3686) events. With the quantum entangled decays of J/ψ, we can search for the new source of CP violation and precisely measure the electric...
位于四川稻城的高海拔宇宙线观测站(LHAASO)在银河系内发现大量拍电子伏伽马源,开启了“超高能伽马天文”观测窗口。但这些源是否为宇宙线的加速源,仍有待确认。高能天体中微子是由高能宇宙线与其他物质相互作用产生的,因其是电中性粒子,且只发生弱相互作用,是寻找高能宇宙线起源的关键信使之一。为此,我们提出在深水下建设30立方公里的阵列来探测高能中微子事例,即高能水下中微子望远镜(HUNT)项目。经过三年的技术积累和试验,我们成功在南海和贝加尔湖开展了样机投放和测试工作,实现多项关键技术突破和验证。本报告将详细介绍HUNT项目的设计、样机性能及测试进展。
RELICS实验(REactor neutrino LIquid xenon Coherent Scattering experiment)旨在利用双相型液氙时间投影室(LXeTPC)技术,在极低核反冲能量区间($\mathrm{[0.3, 1]~keV_{nr}}$)探测反应堆中微子与原子核的相干弹性散射(CEvNS)信号。我们的近期目标是研发敏感体积为 $\mathrm{10~kg}$ 的液氙探测器(RELICS-10),计划部署于浙江三门核电站距堆芯约 25 m 处,预期在一年曝光量下可测得对 CEvNS 信号,显著度约为$5\sigma$。
CEvNS...
江门中微子实验(JUNO)旨在通过精确测量反应堆中微子能谱来确定中微子质量序,这要求探测器达到前所未有的 3% @ 1 MeV 的能量分辨率。为了逼近这一物理极限,并从存在 PE 堆叠和暗噪声光电倍增管(PMT)波形中提取亚纳秒级的时间与电荷信息,JUNO 合作组在其数据分析和重建链条中深度引入了人工智能(AI)与机器学习技术。
本报告将系统性地介绍 JUNO 在波形分析、重建及刻度中使用的核心 AI 方法。报告内容不仅涵盖已取得显著成果的深度学习模型(如卷积神经网络 CNN 与 Transformer),还将重点展示我们在广义机器学习领域的最新前沿探索,如基于 JAX 的可微编程与连续归一化流(cNSF)技术的应用。通过结合物理第一性原理的机器学习架构(如...
Among the charged leptons, the $\tau$ electric dipole moment ($d_\tau$) is the least constrained. We show that the Im[$d_\tau$] imposes strong constraints on new physics that have yet to be discussed. Motivated in particular by the Super Tau-Charm Facility (STCF), which will provide a uniquely clean environment for precision $\tau$-physics, we study the momentum-transfer dependence of...
我将报告LHCb上双重味重子实验研究近期进展,包括单电荷双粲重子的首次发现,这是利用升级后的LHCb探测器发现的首个新粒子。
This presentation elaborates on the latest advances in the development and characterization of a 6.6 kg prototype CryoCsI detector, alongside a pulse shape discrimination (PSD) method for suppressing the dominant afterglow background. The detector achieves a high light yield of 29 PE/keVee and an energy resolution below 8% at 60 keV, accompanied by excellent long-term stability. Additionally,...
This talk reviews recent results of exotic physics searches at the CMS experiment. The selected results either applied novel analysis techniques that significantly extended previous search limits, or observed hints of excess.
Exotic physics searches include, but are not limited to, heavy fermions, heavy gauge bosons, extra dimensions, and model-independent general searches.
In this talk, we will present our recent results on the $J/\psi$ and exotic hadron productions in high energy nuclear collisions using the parton and hadron cascade model PACIAE. For the $J/\psi$ sector, we will provide a quantitative analysis of the relative contributions for different production mechanisms and their energy and rapidity dependence in the inclusive $J/\psi$ production. We will...
畴壁是从早期宇宙相变过程中离散对称性破缺过程中诞生的一类拓扑缺陷。最简单的畴壁来源于$Z_2$对称性的破缺。近年来,人们不再满足于研究这种$Z_2$对称性的破缺产生的简单畴壁,进而开始研究更复杂的离散对称性破缺产生的畴壁,包括更大的循环群$Z_n$以及非阿贝尔对称群$A_4$、$S_4$等。在这些对称性破缺产生的畴壁中,可能存在不稳定畴壁、复合畴壁、CP破坏畴壁等新的现象。
太阳中微子是研究太阳核聚变过程、检验标准太阳模型以及探索中微子振荡的重要探针。液氩探测器可通过Ar-40的带电流反应探测电子味太阳中微子,尤其适用于B-8和hep等高能太阳中微子的研究。NOAr(Neutrino Observatory with Argon)实验依托中国锦屏地下实验室(CJPL)平台,面向液氩太阳中微子探测中的关键技术问题,开展掺氙单相液氩探测器原型研究,重点包括低温光读出、电场结构、信号响应和数据采集流程等方面。本报告将介绍NOAr原型机试运行阶段的初步进展,包括光探测器性能、慢控制系统、信号读出与波形分析结果,并在此基础上讨论未来不同探测器参数下对太阳中微子、超新星中微子等信号的物理预期。
Using the form factors of the transtions $B\to T$ with $T$ refering to a tensor meson, such as $a_2(1320), f_2(1270),K^*_2(1430), D_2^*(2460)$ and $D^*_{2s}(2573)$, within the covariant light-front quark model (CLFQM), we
provide a detailed investigation of the corresponding semi-leptonic decays $B\to T\ell\nu_\ell$ with $\ell=e,\nu,\tau$. All the branching ratios of these
decays are larger...
We will investigate the Spin Alignment and Phase Structure of Thermal QGP under Rotation, and the Anomalous Magnetic Moment and Phase Transition of the Magnetized
QCD Background with the finite temperature field theory; and we also study the rotation effect on the deconfinement phase transition in Holographic QCD. And then we make summary and conclusions.
Liquid scintillators are widely used in particle and nuclear physics. Understanding the scintillation and quenching mechanisms is a fundamental issue in designing a high-light-yield liquid scintillator. In this work, the basic scintillation process for two-component liquid scintillators is discussed, highlighting the processes of excitation, ionization, and anion-cation recombination. A...
Leptogenesis is a highly competitive class of theories that explains the baryon asymmetry of the universe. In this talk, I will discuss contributions of new physics effects to the Leptogenesis, including but not limited to non-restoration of the electroweak symmetry, chiral magnetic effects, and explicit breaking of the PQ symmetry.
In this talk, we will present our recent results on the QCD matter. We construct a hybrid equation of state (EoS) by smoothly interpolating the EoS in the hadron resonance gas at low temperatures to that in the ideal parton gas at high temperatures, and employ it to study the properties of the quantum chromodynamics (QCD) matter at a finite magnetic field and nonzero chemical potential. We...
Tau 物理是Belle II实验上的重要研究课题之一。Belle II目前已经采集了842 pb-1数据,并正在产出越来越多的tau物理研究成果。本报告题目是 “tau physics at Belle II”, 将报告Belle II实验最新的tau物理研究进展,包括通过 tau->pi Ks nv寻找CP破坏,一系列tau衰变中寻找轻子味破坏,tau轻子寿命的测量等课题。
COMET实验位于日本东海的J-PARC质子加速器研究中心,旨在以超高灵敏度搜寻带电轻子味破坏过程(CLFV过程),即无中微子伴随的μ-e转换(μ⁻ + N → e⁻ + N)。在标准模型中,轻子味严格守恒,此类CLFV过程被严格禁止;但在一些超出标准模型的新物理模型中(如超对称理论等),预言了其分支比将显著增强。因此,COMET实验是寻找超出标准模型的新物理最有力工具之一。COMET实验采用高强度脉冲质子束轰击静止靶产生大量π介子,π衰变产生的μ子经超导螺线管磁铁捕获并输运至铝制停止靶,形成μ子原子。COMET实验利用脉冲式束流、主动宇宙学屏蔽以及精心设计的偏转磁铁系统,可有效抑制本底事件。COMET实验采用分阶段实施的方法,分为了Phase-I和phase-II。Phase-I 预计物理灵敏度可达约...
切伦科夫探测器由于其良好的角度分辨能力,被广泛用于中微子的方向探测,特别在太阳中微子、地球中微子的探测中具有非常重要的意义,但光产额相对较低,对低$MeV$能区能量分辨能力不足。液闪材料光产额高,在探测中微子信号方面通常具有较高的能量分辨,但发光均匀,无法探测信号方向。新型的切伦科夫探测器则能够结合二者优点,使用慢液闪材料,在$ns$尺度具有分离切伦科夫光和闪烁光的能力。基于此我们开发了波形分析算法,从探测器接收波形中解析出每个真实光子信号的到达时间。我们也开发了基于慢液闪材料的重建算法,能够同时获得方向和能量的良好分辨。目前该方案已在锦屏$1t$原型机上做了测试,我们通过使用$AmBe$源信号,根据级联衰变特征筛选出单能$\gamma$信号,使用重建算法重建$\gamma$信号的方向,能够显示出方向特征。我们也在锦屏百吨探测器的实验条件下模拟了算法的方向重建能力,$5MeV$的电子...
The ATLAS collaboration has released its next-generation flavour tagging algorithm, based on a transformer architecture [1]. The performance is enhanced significantly and the performance in data matches that in the simulation. Recent physics analyses have reported large improvements in sensitivity thanks to the new tagger [2]. In this talk, I will discuss how the tagger was developed and the...
本研究针对无中微子双贝塔衰变探测中的本底抑制难题,提出一项创新技术方案。当前以SNO+为代表的液闪探测器虽能量分辨率优异,但缺乏粒子方向信息,难以有效区分信号与太阳中微子及γ本底。基于SNO+原型,提出通过系统性升级光电读出系统,利用快液闪中契伦科夫光(方向性、瞬时)与闪烁光(各向同性、延迟)的时间特性差异,采用高精度PMT与高速电子学在时间域分离两种光子,通过契伦科夫光重建粒子方向,结合两者信息重建时间、顶点和能量。构建国际首个兼具高能量分辨与方向灵敏度的六维(三维空间、时间、能量、方向)全信息中微子快液闪探测器,为无中微子双贝塔衰变研究提供全新本底鉴别手段。
暗物质粒子探测卫星“悟空”号是我国发射的第一颗用于空间高能粒子观测的卫星,其核心科学目标除了通过对电子宇宙线和伽马射线的观测来间接探测暗物质粒子,还包括通过探测宇宙线核素粒子来研究宇宙线物理。宇宙线是来自外太空的高能粒子,主要包括各种原子核和少量的正负电子、高能伽马射线和中微子等。“悟空”号具备优异的电荷分辨本领,可以对高能宇宙线核素粒子进行高精度鉴别,并对它们的能谱在宽能段内进行精确测量。“悟空”号相继在宇宙线成分能谱精确测量方面取得突破性进展,将空间直接测量拓展至PeV能区,发现了系列重要的新能谱结构,为揭示高能宇宙线的起源、加速和传播机制这一重大科学问题提供了新的依据。
Dark matter, neutrinos, and high-energy cosmic rays are frontier areas of particle physics and astrophysics, closely related to cosmic and stellar evolution. The China Jinping Underground Laboratory (CJPL) features the deepest rock overburden in the world, which can significantly suppress low-energy cosmic-ray muons, providing a unique environment for detecting atmospheric neutrinos and...
This report presents recent LHAASO measurements of Galactic gamma-ray emission, including ultra-high-energy emission from microquasars, diffuse emission from the Galactic plane, and gamma rays from nearby giant molecular clouds. The microquasar observations reveal gamma-ray spectra extending beyond 100 TeV, indicating efficient particle acceleration in accreting black-hole systems. The...
We invent a new method of bootstrapping multi-loop QCD amplitudes. Using the analytic function space of two-loop six-point Feynman integrals, an ansatz was set for the two-loop six-gluon QCD amplitudes. From the collinear and triple collinear limits, the weight-four and leading colour part of two-loop six-gluon amplitude is uniquely fixed.
Light-cone distribution amplitudes (LCDAs) are fundamental nonperturbative objects governing hard exclusive processes and heavy-flavor decays. Over the past decades, lattice QCD studies of LCDAs have evolved from traditional calculations of low-order moments to the recent development of approaches based on large-momentum effective theory (LaMET), which enable direct access to the Bjorken-x...
XXX
Hadronization, the dynamical realization of color confinement in QCD, is the central process connecting the quark-gluon plasma (QGP) produced in relativistic heavy-ion collisions to the hadronic observables measured in detectors. Yet it remains beyond the reach of existing first-principles frameworks, as semi-classical generators lose quantum coherence while lattice QCD cannot access real-time...
In this talk, we report the first complete results of the four-loop non-singlet splitting functions in QCD. Splitting functions govern the scale evolution of parton distribution functions, which enter the theoretical predictions for all physical processes at high-energy hadron colliders. According to their flavor group structure, splitting functions are classified into non-singlet and singlet...
Light-cone distribution amplitudes (LCDAs) frequently arise in factorization theorems involving light and heavy mesons. We will talk about the power corrections in the extraction of the B-meson LCDAs.
We point out that a multi-TeV muon collider can simultaneously be a high energy neutrino collider as a result of radiations of soft electroweak gauge boson $W^\pm$. We consider the processes $\mu^+\mu^- \to \ell^+\ell^-$, $\nu\mu^\pm \to \nu \ell^\pm$ and $\nu\bar \nu \to \ell \bar\ell$ near the collider energies to probe the physics beyond the Standard Model. We adopt simplified models with...
Understanding how quarks and gluons evolve and lose energy as they traverse a colored medium is central to interpreting jet observables in high-energy nuclear collisions. We investigate this using a non-perturbative light-front Hamiltonian approach, where the physical quark — dressed by its gluon cloud — is treated as the eigenstate of the vacuum QCD Hamiltonian, and its real-time quantum...
BESIII has collected 20.3 and 7.33 fb^-1 of e+e- collision data samples at 3.773 and 4.128-4.226 GeV. These constitute the world's largest samples of D anti-D and Ds anti-Ds pairs, respectively, providing a unique laboratory to probe the non-perturbative dynamics of Quantum Chromodynamics (QCD) in the charm sector. We will present the measurement of branching fractions of fifteen Ds+ hadronic...
The production of beauty hadrons in proton-proton (pp), proton-lead (p-Pb), and lead-lead (Pb-Pb) collisions offers critical insights into heavy-flavor hadrons production mechanisms across different collision systems. This work presents Bayesian unfolding data-driven measurements of the open beauty hadron production, utilizing ALICE and LHCb data to recover full kinematic information from the...
磁单极子是高能物理前沿的重要假想粒子,其探测对验证基础理论具有关键意义。针对现有探测技术受限于成本或磁特征识别能力的不足,SCEP实验组设计了独特的基于量子传感读出的磁学探测模块,并与传统粒子探测器构建符合探测系统。该系统旨在突破现有探测技术瓶颈,并为深空磁单极子搜寻提供支撑。SCEP实验的核心物理目标包括磁单极子与轴子等宇生奇异粒子。本报告将重点介绍面向不同速度磁单极子的磁探测模块、粒子符合模块及后端电子学与读出算法等方面的研究进展
环形成像切伦科夫探测器(RICH)是AMS实验实现高精度速度测量和宇宙线同位素分辨的关键子探测器。通过同时结合磁谱仪给出的刚度信息与RICH测量的粒子速度,可以在GeV/n能区实现对轻核同位素的质量重建,为研究宇宙线产生、传播以及核碎裂过程提供重要实验输入。本报告围绕AMS实验RICH探测器的在轨标定与物理重建方法展开介绍。首先,报告将讨论RICH探测器在同位素重建中的作用,重点说明速度分辨率、切伦科夫角测量精度以及辐射体性质对质量分辨能力的影响。其次,介绍RICH在长期空间运行条件下的在轨位置校准方法,包括探测器几何对准、光子击中信号修正以及与AMS其他子探测器轨迹信息的联合约束。随后,报告将介绍气凝胶和NaF辐射体折射系数的在轨标定方法,分析折射率微小变化对切伦科夫角和速度重建的系统影响。在重建算法方面,将重点介绍环形成像切伦科夫光路追踪方法,包括粒子穿越辐射体后的光子发射、传播...
The world’s largest sample of J/ψ events accumulated at the BESIII detector offers a unique opportunity to investigate η and η′ physics via two body J/ψ radiative or hadronic decays. In recent years the BESIII experiment has made significant progresses in η/η′ decays. A selection of recent highlights in light meson decays at BESIII are reviewed in this report, including the precision...
本报告将介绍在1.9到25 GV刚度范围内宇宙线锂-6与锂-7同位素能谱测量结果。该结果基于阿尔法磁谱仪(AMS)2011年5月至2023年10月在轨采集到的97万个锂-6与104万个锂-7同位素事例完成。测量结果表面,锂-6与锂-7同位素能谱具有几乎相同的时间演化结构,在约4 GV之上,锂-6、锂-7、氦、铍、硼、碳、氮、氧原子核具有相同的时间演化结构。在约7 GV之上,锂-6与锂-7同位素能谱具有相同的能谱形状。这揭示了二者均由更重的宇宙线原子核在传播过程中与星际间介质碰撞碎裂而产生的,排除了锂-7同位素能谱中存在显著初级组分的可能性。
本报告将介绍国际空间站上的阿尔法磁谱仪(AMS)对磷、氯、氩、钾、钙等宇宙线重核能谱的最新测量结果。AMS在GV至TV的刚度(动量/电荷)区间内对这五种元素的能谱进行了测量,这是迄今为止对上述宇宙线能量最高、精度最高的观测。通过对能谱结构的深入分析,我们发现上述5种原子核均同时包含初级和次级两种宇宙线成分。此外,我们采用独立于宇宙线传播模型的方法,计算了各原子核在天体源处的丰度比,为研究宇宙线起源提供了关键数据。最后,综合研究AMS所测得的氦至钙(电荷数Z=2-20)原子核能谱的刚度依赖性,我们发现总共存在两类初级宇宙线和两类次级宇宙线,其他所有原子核的能谱,均可由这些初级和次级宇宙线成分的线性叠加来描述。
We calculate all three-loop, five-point, massless planar Feynman integral families in the dimensional regularization scheme. This is a new milestone in Feynman integral computations. The analysis covers four distinct families of Feynman integrals for this configuration, for all of which we derive the canonical differential equations. Our results also confirm a prediction on the three-loop...
宇宙线反氘核是暗物质湮灭或衰变等新物理过程的灵敏探针之一,其在低能区的天体物理二次产生本底预期极低 。阿尔法磁谱仪 (AMS) 是目前唯一长期运行于国际空间站的大型粒子物理磁谱仪,自2011年运行至今,已累积超过2600亿个宇宙线事例,能够通过永磁体偏转结合多子探测器系统精确鉴别粒子的电荷符号、动量、速度与质量,从而对反物质粒子具有独特的鉴别能力 。本报告将介绍AMS在反氘搜寻方面的最新分析进展,重点讨论探测器性能、粒子鉴别策略以及系统性研究等方面的工作。
The muon anomalous magnetic moment, aμ = (g−2)/2, and the muon electric dipole moment are precision observables with exceptional sensitivity to physics beyond the Standard Model. The successive Muon g−2 experiments at CERN, Brookhaven, and Fermilab were recognized with the 2026 Breakthrough Prize in Fundamental Physics, highlighting the long-standing impact of this program on precision tests...
Short-range correlation pairs (SRCs)---core of nuclear structure, composed of highly off-shell nucleons---are mostly studied via electron-nucleon scattering, leaving a gap in meson-based probes. We propose probing SRC off-shell nucleons via quasielastic $\pi^+$-bound proton scattering ($\pi^+ p \to \pi^+ p$) at electron-positron colliders, of which the beryllium-based ($^{9}$Be) beam pipe of...
Migdal效应近年来因其对亚GeV暗物质探测器灵敏度提升的重大贡献而引起了广泛关注。本报告将介绍MARVEL团队设计的气体微像素探测器在D-D源上直接观测米格达尔效应。我们将介绍探测器结构及性能测试结果、D-D束流实验的详细过程,以及数据分析和相关成果。我们将讨论探测器升级工作的进展情况以及后续的数据采集计划。
高能伽马射线观测研究是理解剧烈、瞬变天体活动,诸如宇宙线加速器、银河系超新星、双中子星并合、AGN 等天体现象多信使天文观测研究不可缺少的部分,已成为当今世界上最活跃的非电磁波探测和研究手段。2019年,我国西藏羊八井ASγ实验利用其创新型地下缪子水切伦科夫探测阵列,国际首次发现来自蟹状星云方向能量高于100 TeV(100万亿电子伏特)伽马辐射,最高光子能量达 450 TeV(450万亿电子伏特),宣告对极端宇宙的探索首次迈入 100 TeV 以上观测能区。近年ASγ实验取得了多个重大成果,本报告主要介绍ASγ实验观测现状及其相关天体物理前沿问题。
脉冲星风云(PWN)是银河系内高能粒子的重要加速源,也是研究相对论激波、磁场耗散、粒子输运和宇宙线粒子起源的关键天体系统。近年来,LHAASO凭借在TeV至PeV能区的高灵敏度和大视场巡天能力,显著推进了PWN的超高能伽马射线研究。以Crab Nebula为基准,LHAASO直接探测到PeV伽马射线辐射,证明年轻PWN能够将电子加速到PeV能量;随后,PSR J1849−0001供能的Aquila Booster显示,远低于Crab自转能损失率的脉冲星也可驱动PeV级伽马射线源,并对传统的PWN粒子加速模型提出挑战。与此同时,LHAASO对CTA 1、PSR...
在本报告中,针对具有C宇称的三体强子系统,我们预言了一个良好的三体强子分子态候选者。该态不与传统的两体强子分子态及QCD裸态混合,我们进一步介绍了其质量、衰变性质和产生过程,并探讨了其在未来实验中是否可被观测到。此外,我们发现在该系统中存在一种与C宇称相关的相互作用,表现为三体力。通过系统分析该系统的质量与均方根半径,以及哈密顿量平均值,我们确认了一个研究三体力的理想体系。
We present a theoretical study of global and azimuthal-angle-dependent $\Lambda$ hyperon polarization in isobaric $^{96}_{40}$Zr+$^{96}_{40}$Zr collisions at $\sqrt{s_{NN}}=200$ GeV using the TRENTo-3D initial condition model coupled to (3+1)-D viscous hydrodynamic model CLVisc. A longitudinal flow velocity gradient, controlled by $f_v$, is introduced into \trento\ for the first time,...
为满足PandaX-20T暗物质探测器对超痕量本底需求,本研究自主研发了两套超高纯氙低温精馏系统,分别用于去除探测器介质氙中的氪(Kr)与氡(Rn),目标是将氙中氪浓度降至2 nBq/kg(10-14 mol/mol)、探测器中氡水平从8 µBq/kg降至1 µBq/kg(10-25 mol/mol)以下。PandaX-20T超高纯氙除氪低温精馏系统采用填料塔,提纯速率由PandaX-4T的10kg/h提升至30 kg/h,回流比为191。PandaX-20T超高纯氙除氡低温精馏系统与探测器耦合采用液相大流量精馏,设计流量可达856 kg/h(液相5LPM),为此自主研发了基于R14节流制冷的20 kW大冷量回收循环系统,该系统通过与精馏塔耦合,实现冷量的转移与回收,避免机械部件放氡,攻克了大流量精馏的冷量供给不足问题。目前除氪系统已完成调试,将原料氙中的氪浓度从2ppm提纯到8...
Based on the large data samples of 10 billion J/ψ and 2.7 billion ψ(3686) events collected with the BESIII detector, recent progress in hyperon spectroscopy, including the observations of Ξ(1720) and Σ(2330), will be presented. In addition, new radiative decay modes of Λ(1520) and Λ(1670) will be reported. Prospects for hyperon spectroscopy and decay studies at BESIII will also be discussed.
带电宇宙线进入日球层后因太阳调制而发生流强的改变,太阳活动则导致宇宙线流强随时间而变化。精确测量不同种类、不同能量的宇宙线粒子随时间的变化是认识宇宙线日球层传播过程的重要实验手段。阿尔法磁谱仪(AMS)是安装在国际空间站上的大型磁谱仪实验,能够同时测量物质和反物质。本报告将介绍AMS宇宙线自2011年至2025年14.5年间电子、正电子每日流强测量的最新结果,并讨论这些结果所展现的太阳调制与电荷符号、宇宙线本地星际能谱(LIS)等因素的相关性。
CICENNS实验采用300 kg碘化铯闪烁体探测器,旨在利用中国散裂中子源(CSNS)产生的中微子,实现对中微子-原子核相干弹性散射(CEvNS)的精确测量。CsI(Na)闪烁体以高原子序数带来的相干增强、420 nm发射峰与PMT的最佳匹配、极低本底及弱余辉特性,成为探测CEvNS低能核反冲信号的理想介质。本报告介绍了CICENNS实验的CsI(Na)闪烁体探测器的设计优势、研制进展及性能测试。
此外,为定量刻画CSNS中子束流产生的本底,我们利用EJ276快响应塑料闪烁体的脉冲形状甄别(PSD)能力对CSNS靶站平台约MeV能量的快中子/伽马辐射进行了测量。
We present an upgraded formula for Wigner function and spin polarization of fermions emitted by a relativistic fluid at local thermodynamic equilibrium at the freeze-out which improves the one obtained in literatures and used in numerical simulations of relativistic nuclear collisions. By using a new expansion method applicable to freeze-out hypersurfaces with arbitrary geometry, we reproduce...
We present the design and the sensitivity reach of the Qubit-based Light Dark Matter detection experiment. We propose the novel two-chip design to reduce signal dissipation, with quantum parity measurement to enhance single-phonon detection sensitivity. We demonstrate the performance of the detector with full phonon and quasiparticle simulations. The experiment is projected to detect $> 30$...
Analysis of anisotropy of galactic positrons, electrons, protons and light nuclei has been performed with the Alpha Magnetic Spectrometer on the International Space Station using data from 2011 till 2025. Anisotropy measurement allows to differentiate between point-like and diffuse sources of cosmic rays for the understanding of the origin of high energy positrons or the hardening in the...
MeV gamma-ray imaging is important for astrophysics, nuclear physics, nuclear security, and medical physics, but conventional collimated systems often suffer from low detection efficiency. Compton imaging provides a promising alternative by reconstructing the incident gamma-ray direction from event topology.
In this study, we investigate a compact hybrid Cherenkov–scintillation Gamma tracker...
低质量粲偶素自旋单态eta_c和h_c粒子是研究粲偶素衰变动力学、检验强相互作用相关模型的重要实验平台。利用BESIII实验采集的27亿psi3686和100亿J/psi事例,本报告将介绍近期关于自旋单态粒子产生和衰变研究的进展,包括首次测量eta_c -> gamma gamma衰变的绝对分支比、对Jpsi-> gamma eta_c电磁跃迁衰变分支比的精度测量,首次观测到若干eta_c衰变模式,以及发现h_c的辐射衰变gamma f_2(1270)等。这些结果为理解非微扰QCD效应提供了新的实验信息。
Entanglement generated in the early stage of relativistic heavy-ion collisions (HIC) is considered a direct and fundamental source for understanding fast thermalization, entropy production, and evolution. Spin entanglement in QCD, arising from non-commutative geometric effects of quantum fields, provides a new avenue to explore the quantum informational footprint of the QCD topological vacuum...
The spin polarization of Lambda hyperon in low-energy Au-Au collision can be generated from the nonlocal nucleon-nucleon scattering. The Lagrangian of baryon-meson interaction is obtained from the chiral perturbation theory, and we introduce a wave packet for the incoming nucleons to describe the nonlocal collision. We evaluate the spin dependent cross section with the approximations that the...
保罗·谢尔研究所(PSI)的muEDM实验旨在以前所未有的灵敏度测量μ子的电偶极矩(EDM),目标精度为$σ(dμ) = 6×10^{-23} e·cm$,这比布鲁克海文国家实验室(BNL)缪子g-2实验确立的当前极限提高了三个数量级。该工作的核心是位于螺线管入口处的μ子触发探测器(TrigDet),它能够快速、精确地识别螺线管存储阈值内的缪子。该触发器会触发脉冲磁场,将μ子引导至稳定轨道;在此轨道上,径向电场使“冻结自旋”技术得以应用,从而分离出由电偶极矩(EDM)引起的自旋进动。
TrigDet 采用由硅光电倍增管(SiPM)读出的塑料闪烁体,由两个子系统组成:一个用于入射缪子探测的厚度不足一毫米的 Gate...
本次报告中我会介绍下电弱相变引力波基于空间引力波探测器太极等的探测预期研究,及相应的唯象学研究方面的影响,如基于太极对希格斯耦合探测的预期等。
In this talk, we review the recent result from ATLAS on the all-charm tetraquark search. It covers both the di-J/psi and J/psi+psi(4S) final states. Fitted resonance parameters from different fit models are compared. The ratio of branching fractions of X(6900) decaying into these two states is also provided. These results shed light on the nature of the all-charm tetraquarks.
宇宙线缪子作为一种天然的探针,在粒子物理研究中具有重要应用价值。为满足对宇宙线缪子及其他带电粒子径迹的高精度探测需求,本研究成功研制了一套基于硅光管与闪烁光纤的位置灵敏探测器。该探测器由八个探测大层构成,单层有效探测面积为 400 mm × 200 mm。每个大层包含两组X方向与两组Y方向的闪烁光纤阵列,构成二维位置敏感单元。闪烁光纤直接耦合到 3 mm × 3 mm 的硅光管阵列上,每大层共设 128 个X通道与 64 个Y通道,并配备独立FPGA模块实现信号的实时采集与预处理,最终由中央开发板完成数据汇总。本报告重点介绍了该探测器的设计原理、制作工艺与性能测试过程,并对关键部件的国产化替代方案进行了探讨。测试结果表明,探测器具备高探测效率,位置分辨率可达约 1 mm,适用于带电粒子的精确位置测量,且全国产化零部件能够满足仪器性能要求。
The spin correlation of back-to-back dihadrons emerges in unpolarized high-energy collisions, empowering unpolarized experiments to shed light on spin-dependent fragmentation functions. Transverse spin correlations of partonic $q\bar{q}$ pair manifest through dihadrons, providing a novel probe for the chiral-odd fragmentation function $H_{1T}(z)$. However, although produced gluon also exhibit...
在中微子和稀有事件探测实验中,宇宙线μ子产生的本底是一个主要问题;而在大型宇宙射线探测实验中,如何在保证良好性能的同时控制成本也是一大挑战。因此,开发低成本、高性能的新型宇宙线探测器具有重要价值,其中基于液体闪烁体的方案展现出良好潜力。本研究通过对比蒙特卡罗模拟与实验测量,评估了基于液体闪烁体和波长位移光纤的探测器的性能,包括光产额、宇宙线探测效率等。实验数据与模拟结果基本一致。此外,研究进一步对比了仅使用液体闪烁体的不同探测器方案,旨在提出一种结构更简化、性能更优的设计。初步结果表明,该方案在宇宙射线观测实验中具有重要的应用前景。
The BESIII experiment is a symmetric e+e- collider operating at c.m. energy from 2.0 to 4.95 GeV. With the world’s largest threshold production data set of J/ψ (10 billion), ψ(3686) (2.6 billion), and 20 fb^-1 D meson pairs from ψ((3770) decay, we are able to search for various dark sectors produced in e+e- annihilation and meson decay processes. In this talk, we report the search for...
引力波的发现赋予了人类研究宇宙的“听觉”。我将报告我们组近期在空间引力波数据处理方面的新进展,包括采用卡曼滤波来处理数据间断[arXiv:2507.02458],使用机器学习[PRD 111 (2025) 103025]、量子计算[PRD 112 (2025) 083004]和基于龙算法的量子计算[arXiv:2603.17698]对引力波数据处理进行加速,以及提高机器学习特征的可解读性[Machine Learning: Sci. Technol. 6 (2025) 035045]等。
The search for the particle nature of dark matter has entered a new era of multi-messenger astrophysics. We are developing a novel tracking-calorimeter to explore two promising indirect detection channels: low-energy cosmic antinuclei and MeV gamma rays. We innovatively hybridize the detection technique using exotic atomic formation/decay and multi-layer Compton imaging into one detector...
The DArk Matter Particle Explorer (DAMPE), which is a space-based high energy particle detector, has been operated in orbit for ten years. Thanks to its large geometric factor, good charge resolution and wide dynamic range in energy measurement, DAMPE can provide valuable insights on the energy spectra of cosmic-ray up to hundreds of TeV. Using nine years of on-orbit data, the DAMPE...
Neutron stars (NS's) with their strong magnetic fields and hot dense cores could be powerful probes of axions, a classic benchmark of feebly-coupled new particles, through abundant production of axions with the axion-nucleon coupling and subsequent conversion into X-rays due to the axion-photon coupling. In this article, we point out that the pulsation structures in both the intensity and...
The talk with present the cross section measurements of the Higgs bosons decaying to a pair of hadronically decaying tau leptons in the high Lorentz-boosted regime. The analysis is based on the full Run 2 dataset of proton-proton collisions at a center-of-mass energy of √s=13 TeV and a partial Run 3 dataset at √s=13.6 TeV collected in the 2022-2024 period by the ATLAS experiment. The analysis...
利用AMS宇宙线数据,我们测量了1~42GV宇宙线反质子随时间的变化情况。和其它几种宇宙线基本电荷粒子(质子、正电子、电子)相比,反质子随时间变化规律有着显著的不同。AMS实验的四种宇宙线基本电荷粒子的同步测量,为研究宇宙线在太阳系中的传播规律,及其与粒子质量、电荷符号和能谱形状的关系提供了独特的视角。
BESIII has accumulated 4.5 fb^-1 of e+e- collision data within the 4.6 and 4.7 GeV energy range, which provide the largest dataset of Lambda_c- Lambda_c pairs in the world. We will present a novel way for exploring CP violation using the Lambda_c- Lambda_c threshold data and the first observation of the transverse polarization of Lambda_c+ in the reaction e+e--> Lambda_c+ Lambda_cbar-....
A search for pairs of light neutral pseudoscalar bosons ($A$) resulting from the decay of a Higgs boson is performed. The search is conducted using LHC proton-proton collision data at $\sqrt{s}=13~\mathrm{TeV}$, collected with the CMS detector in 2016--2018 and corresponding to an integrated luminosity of $138~\mathrm{fb}^{-1}$. The $A$ boson decays into a highly collimated electron-positron...
Scalar leptoquarks are scalar bosons that couple simultaneously to a quark and a lepton. They commonly appear in the Higgs sectors of grand unified theories. Stringent experimental limits on proton decay imply that these particles are superheavy. Graviton bremsstrahlung from the decays of such superheavy leptoquarks, arising from quantum gravitational processes, offers a promising source of a...
CDEX合作组使用高纯锗半导体探测器在位于四川西昌的中国锦屏地下实验室(CJPL)开展暗物质探测和无中微子双贝塔衰变实验研究。本报告将简要总结CDEX-1和CDEX-10两个实验阶段的物理成果,并重点介绍目前正在建设的CDEX-50暗物质实验和CDEX-300v无中微子双贝塔衰变实验,以及面向未来大型高纯锗阵列实验的一系列关键技术预研。
A search for the Higgs boson decay to a $Z$ boson and a photon in the $\ell\ell\gamma$ ($\ell = e, \mu$) final state is performed using $pp$ collisions at $\sqrt{s}=13.6~\mathrm{TeV}$ recorded with the ATLAS detector at the Large Hadron Collider during 2022--2024, corresponding to an integrated luminosity of $165~\mathrm{fb}^{-1}$. The signal yield, normalised to the Standard Model prediction,...
BESIII实验在质心能量位于3.7 GeV到4.95 GeV之间的近50个能量点采集了积分亮度约50 fb-1的精细扫描数据,对多个遍举反应过程的产生截面进行了精确测量,包括开粲末态、隐粲末态以及轻强子末态。通过对反应截面线型的研究,在重子末态中发现psi3770显著的信号;在高质量能区也发现多个反应过程的截面在4.5 GeV、4.6 GeV和4.75 GeV附近有增长。该报告将总结近期BESIII实验在矢量粲偶素和类粲偶素研究方面的最新进展,这些精确的测量将为理解矢量粒子的性质提供重要实验输入。
We investigate the nonlinear response of flow harmonics v2, v4 to initial-state eccentricities ϵ2, ϵ4 within the Gubser-flow framework. By extending the perturbative solutions of Gubser flow, we derive analytic nonlinear response relations connecting the eccentricities ϵ2, ϵ4 to the flow harmonics v2, v4. Our results reproduce the well-known result v4/v2^2 → 1/2 in large transverse momentum pT...
The talk will present the recent results of Higgs boson property measurements and new resonance searches in the diphoton channel at CMS. The talk will cover the published results of the relevant analyses IHEP dominated and contributed in past 2 years, including the Higgs boson mass and cross section, low-mass and very low-mass diphoton resonances, and the resonant HH/HY with H decaying into...
In high-energy physics experiments, calorimeter simulation involves a wealth of physical interaction processes, and the resulting particle showers encapsulate critical physical information. However, calorimeter simulation also incurs enormous computational resource overhead. Previous studies have addressed the growing computational pressure through machine learning, while quantum machine...
在基于智能体的现代软件开发范式中,性能验证作为系统反馈闭环的核心环节,其重要性日益凸显。其中大语言模型构成"大脑"负责认知推理,技能库作为"四肢"执行操作,Agent扮演 "意识指挥"统筹全局,而性能验证系统则是不可或缺的"感官系统"——唯有通过它感知代码变更对系统性能的量化影响,才能实现真正意义上的迭代式开发。
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We present a theoretical study of the azimuthal decorrelation $\delta\phi$ and transverse momentum imbalance $q_T$ in dijet production at the LHC, offering intriguing insights into the dynamics of quantum chromodynamics. We define the jet axes using the recoil-free winner-take-all (WTA) recombination scheme. For the azimuthal decorrelation $\delta\phi$, this axis choice eliminates non-global...
Visualization tools are used to display the detector geometry and information of event hits. It plays an important role in physics analysis, data quality monitoring, algorithm optimization, physics education, and public outreach. The BESIII experimental dataset is derived from raw data files containing the events information of electron-positron collisions. These data pass through the detector...
This talk will present the latest phenomenological and simulated experimental prospective studies on the new physics opportunities at DarkSHINE Experiment by exploring the physics sensitivity of searching for dark fermions/sterile neutrinos and utilizing the positron beam mode to search for Dark Photon invisible decay signals in comparison with electron beam mode sensitivities.
The initial-state geometry in relativistic heavy-ion collisions provides a novel probe to nuclear cluster structure. For 20Ne, a novel approach is proposed to distinguish between the cluster configurations (5α versus α+16O) in order to gain insight into nuclear structure transitions governed by many-body quantum correlations. Through analytical calculations with the microscopic Brink model and...
XENONnT 是位于意大利 LNGS 地下实验室的液氙双相时间投影室暗物质直接探测实验。本报告综述其近期物理成果。
在标准 WIMP 搜寻中,XENONnT 基于前两轮科学运行的盲分析对自旋无关与自旋相关 WIMP-核子弹性散射截面给出了更新的上限,覆盖 GeV/$c^2$ 至 TeV/$c^2$ 质量区间。在低能核反冲分析中,借助 $^{88}$YBe 光中子源对探测器低能响应的专门刻度,XENONnT 把灵敏度推进至太阳 $^8$B 中微子相干弹性散射 (CE$\nu$NS) 的能量窗口,并完成了对该过程的测量,给出与既有太阳中微子实验一致的 $^8$B 通量。基于同一数据,报告还将介绍在低动量传递下对弱混合角 $\sin^2\theta_W$ 的测量,对新中间矢量介子 $Z'$ 耦合及中微子电荷半径等超出标准模型情形的约束,以及在 CE$\nu$NS...
The $\mu$-$e$ conversion process is one of the most powerful ways to test lepton-flavor-violating (LFV) interactions involving charged leptons. The standard model with massive neutrinos predicts an extremely low rate for $\mu$-$e$ conversion, making this process an excellent probe for testing LFV arising from new physics. Among many theoretical models that can induce LFV, the Supersymmetric...
北京谱仪III(BESIII)是运行在北京正负电子对撞机(BEPCII)上的大型磁谱仪,也是目前国际上唯一运行在陶-粲能区的大科学实验装置。自2009年运行取数以来,面向加速器对撞亮度的多次优化提高以及探测器的重大硬件升级,基于Gaudi架构的BESIII离线软件系统历经十余年发展演变,成功攻克了海量数据高吞吐量处理、操作系统适配、以及大规模精密算法迭代等多重关键技术挑战。作为BESIII实验数据处理的核心,该系统集成了精确模拟、数据重建、探测器刻度与物理分析工具等核心功能,不仅确保了实验装置长期、高效、稳定的运行,更为数据产生和数据分析提供了坚实基础,支撑了大量高水平物理成果的产出。本报告将重点阐述BESIII离线软件在应对探测器升级与技术迭代中的关键架构重构、软件现代化策略,以及其为保障持续不断获得实验物理成果所发挥的关键支撑作用。
Accurate reconstruction of magnetic fields in inaccessible regions is vital for many high-precision experiments in physics. Traditional methods, such as spherical harmonic expansion, often suffer from truncation errors that limit their precision. This study proposes an advanced Physics-Informed Neural Network (PINN) framework for high-precision 3D magnetic field mapping. Unlike conventional...
Belle II实验是设计亮度最高的正负电子对撞超级B介子工厂。运行至今,Belle II实验对撞亮度超过0.5x10^35cm-2s-1的水平,采集的B介子数据样本超过Belle实验。Belle II实验正在开展味物理与CP破坏,强子物理与奇特强子态,新物理等领域的广泛研究。报告将介绍Belle II实验的进展,以及实验升级计划。
This talk will present a measurement of the cross section of W boson pair production in photon fusion (γγ → WW), using an integrated luminosity of 138 fb^−1 of proton-proton collision data collected by the CMS experiment in 2016-2018 at a center-of-mass energy of √s = 13 TeV. Events are selected in the final state with one electron, one muon, and a low multiplicity of tracks associated with...
Cosmological first-order phase transitions provide a unique window into fundamental physics in the early Universe. Theoretically, they involve intrinsically nonperturbative and nonequilibrium quantum field dynamics. Phenomenologically, they can generate observable stochastic gravitational waves and may also play an important role in explaining the origin of the baryon asymmetry and dark...
交流耦合低增益雪崩二极管(AC-LGAD)作为兼具高时间分辨和高空间分辨能力的4D硅探测器技术,在未来高能物理对撞机实验(如CEPC、FCC等)中具有重要应用前景。本报告将介绍我们在AC-LGAD传感器研发、专用读出ASIC(LATRIC)开发以及配套测试体系方面的最新进展。在条型AC-LGAD传感器研发方面,设计目标为实现约40 ps时间分辨能力与约10...
Using (2259.3 +/-11.1) ×106 ψ(2S) events acquired with the BESIII detector, the branching fraction ofψ(2S) → ττ is measured with improved precision to be(3.240+/- 0.023 +/-0.081) × 10−3, where the first and second uncertainties are statistical and systematic, respectively, which is consistent with the world average value within 1 standard deviation. This value, along with those for the...
This talk will give a quick overview of recent ATLAS SM Multi-Boson measurement and Multi-Higgs measurement results including the highlight of recent inclusive diboson, VBS polarization, triboson observation, Tri-Higgs search and Di-Higgs combination results by ATLAS, with emphasis of the deep connection of EWSB and Higgs physics.
重味强子单举半轻衰变是检验标准模型和研究重夸克动力学的重要过程。已有电子末态的粲介子单举衰变研究可以用于提取 HQET 非微扰参数,为进一步研究缪子末态提供了理论基础。
本报告将介绍我们对粲介子缪子末态半轻单举衰变的研究。在标准模型框架下,我们保留有限轻子质量效应,计算相关衰变宽度,并给出缪子末态与电子末态比值的标准模型预言。这类比值中许多共同理论不确定性可以相互抵消,因此是检验轻子味普适性的较干净观测量。
最后,我将简要讨论该结果对 BESIII 和未来超级 tau-charm 工厂相关测量的意义,以及后续引入更高量纲算符贡献的理论改进方向。
中微子-原子核相干弹性散射(CEvNS)的精确测量,对于约束标准模型和探测中微子非标准相互作用具有重要意义。双相型液氙时间投影室(LXeTPC)具有信号放大增强和能量阈值低的特点,是探测CEvNS过程的理想技术。RELICS实验采用LXeTPC技术,探测来自中国台州核反应堆的中微子,其主要挑战之一在于抑制由宇生缪子引发的延迟电子本底。本报告将聚焦RELICS实验的主要本底抑制策略,汇报与之相关的电子学读出、缪子反符合探测器以及数据获取系统研发进展。
为满足阿里原初引力波探测实验(Ali CMB Polarization Telescope,AliCPT)中超导转变边缘传感器阵列(Transition Edge Sensor,TES)在高通道数、宽带宽、高速读出以及长期稳定运行条件下的电子学读出需求,本文设计并实现了一套微波超导量子干涉器件复用器(Microwave SQUID Multiplexer,μMUX)读出电子学系统。该系统由控制板、中频板(Radio Frequency board,RF board)以及 ZCU111 开发板组成,可覆盖 0 至 4.096 GHz 的连续读出带宽,实现对 μMUX 谐振器阵列的激励、上/下变频、数字化采集以及实时信号处理。系统通过中频板完成射频信号的上/下变频和幅度调节;ZCU111...
Inspired by Belle data of $\Lambda$ polarization, the polarized transverse-momentum-dependent fragmentation function (TMD FF) $D_{1T}^\perp$ become a hotspot in both theory and experiments. Several parametrizations of $D_{1T}^\perp$ has been proposed with different assumptions on their flavor dependences. Employing an isospin symmetric framework we studied transverse polarizations of $\Lambda$...
We present a comprehensive next-to-leading order (NLO) QCD sum rule analysis
for light hybrid mesons with JPC = 1−−, incorporating condensates up to dimension-8 and NLO corrections to the perturbative, gluon condensate, and four-quark condensate contributions. These corrections are found to be substantial and reveal the necessity of contributions beyond leading order. Employing both Laplace...
Magnetic monopoles arise generically in unified theories and offer a natural explanation of charge quantization. Beyond collider searches and cosmic-ray experiments, their flux is constrained by Parker-type bounds requiring galactic magnetic fields to survive monopole energy extraction. We formulate a self-consistent Parker bound anchored in the lowest eigenmode of the galactic mean-field...
Multi-boson processes are among the most sensitive tests of the Standard Model. Theoretical predictions for these interactions are extremely precise, so even small discrepancies could point to new physics phenomena. Triboson processes are the rarest of this kind, offering unique sensitivity to probe quartic boson couplings and complementarity with Higgs physics and searches beyond the Standard...
\textbf{摘要:}基于直流超导量子干涉器件(DC-SQUID)的时分复用(TDM)是用于宇宙微波背景(CMB)实验中大型转变边缘传感器(TES)阵列的一项关键读出技术。AliCPT-40G望远镜计划部署一个工作在40 GHz的大规模TES阵列,这要求TDM读出电子学系统具备低噪声、紧凑且高带宽的特性。在TDM系统中,除TES固有噪声外,室温电子学是主要的噪声贡献者,其性能直接影响探测器的能量分辨率。本文设计并实现了一种适用于TDM-SQUID架构的低噪声室温读出电子学系统。该系统集成了TES和SQUID偏置源、磁通锁定环(FLL)读出、数字复用控制以及高速数据采集模块。基于低温下运行的两级TDM SQUID的实测参数,推导了室温电子学在噪声、带宽及压摆率等方面的设计约束条件。测试表明,偏置源实现了极低的等效电流噪声密度:TES偏置低于 0.1...
底强子衰变中的轻子普适性检验是寻找超出粒子物理标准模型的新物理的灵敏探针,也是目前粒子物理实验前沿热点课题。在这个报告中,我们将报告LHCb上关于Bc介子半轻衰变中的轻子普适性检验即R(J/psi)的最新结果。
High-energy small system collisions exhibit remarkable flow-like signatures, but separating soft multiple-parton interactions from hard jet fragmentation in the development of collective behavior remains a critical challenge. This talk presents a unified framework leveraging event topology analysis to cleanly isolate flow-like behavior and jet modification effects in small collision systems....
An efficient and robust Data Acquisition (DAQ) software is vital for the CICENNS detector, which is currently in the assembly and testing phase. This poster presents the development of a DAQ system customized for the CICENNS experiment, featuring synchronized data taking across multiple modules, real-time event and charge monitoring, and a graphical user interface for configuration and...
The contribution of gluon-photon fusion to dijet production in deeply inelastic scattering is typically analyzed in the small-x regime, whereas quark-photon scattering dominates at large x. The transition between these regimes has received less attention. In this work, we calculate the leading-order, twist-four gluon-photon fusion contribution within a generalized high-twist framework for the...
Following the most precise charm lifetime measurements as the first charm wave, which benefited from improved detector performance, the Belle II experiment has recently obtained a new set of charm physics results based on half of the current Belle II integrated luminosity. I will present these results, covering searches for CP violation in charm particles, hadronic decays of charmed baryons,...
This talk presents new perspectives on precision nucleon tomography using high-order QCD calculations and jet substructure. I will discuss the winner-take-all axis for extending qT subtraction to jet processes, enabling NNNLO predictions for SIDIS. Novel observables such as one-point energy correlators access the nucleon transversity distribution. Furthermore, we explore quantum decoherence in...
The existence of a landscape of metastable vacua raises the possibility that our Universe may have undergone quantum vacuum decay at late times. This work explores how such a transition can be tested with cosmological observables, focusing on precision distance measurements and cosmic microwave background (CMB) anisotropies. A set of phenomenological models is constructed in which late-time...
XENONnT is a dual-phase liquid xenon time projection chamber operating at LNGS with a 5.9-tonne active target, designed to search for weakly interacting massive particles (WIMPs). As its sensitivity reaches the irreducible background from solar neutrino coherent scattering, the experiment enters a new regime — the "neutrino fog" — where neutrino and dark matter signals become increasingly...
我们将在报告中介绍一种面向暗光子暗物质探测的实验方案及最新原型机实验结果。该方法利用特殊光学结构增强潜在暗光子信号,并在室温条件下开展探测实验。报告将介绍实验中的弱光标定方法与多像素数据分析策略,以提升对微弱暗光子信号的识别能力。目前原型机已有三个月的曝光数据,尚未观测到具有统计显著性的信号,并据此对暗光子暗物质参数空间给出了约束。
We propose a probe of the TMD and spin asymmetry in back-to-back deep-inelastic scattering using only the signs and directions of charged tracks, with no calorimetric or particle-identification information required.
正反缪子素转化实验(MACE)是我国自主提出的下一代缪子物理实验,旨在寻找破坏带电轻子味的正反缪子素转化过程,是研究超越标准模型的新物理的灵敏探针。该实验将依托我国加速器驱动嬗变研究装置(CiADS)规划的高强度表面缪子束流,预期将转化过程的实验灵敏度较当前国际最好水平提高两个数量级以上。目前已完成概念设计,相关成果发表于《Nuclear Science and...
近年由Arkani-Hamed、何颂等发现的隐藏零点、以及与零点相伴随的称为2-分裂的新因子化结构,揭示了散射振幅的全新解析性质与物理性质。在这个报告中,我将介绍如何从费曼图、BCFW在壳递推关系、振幅的普适展开这三个不同角度来理解隐藏零点与2-分裂,尝试挖掘其物理图像,并讨论从两个方面推广隐藏零点与2-分裂性质——1.推广到更多物理模型;2.推广到圈图层次的费曼积分被积函数。
We systematically investigate the collisional energy loss ($-dE/dz$) and momentum diffusion coefficients ($\kappa_{T/L}$) of heavy quarks traversing the quark-gluon plasma (QGP) across diverse temperature scales. By employing the soft-hard factorization model, we first compute the transport properties at leading order in the QCD coupling, demonstrating that the full results eliminate the...
在太阳中微子以及反应堆中微子的物质效应数值计算中,传统处理通常依赖若干理想化近似。对于地球物质传播,常见做法是采用一维球对称的 PREM 密度模型,并通过一阶近似或等效再生因子描述地球物质效应;对于太阳中微子在太阳内部的传播,则常基于两能级绝热演化框架,结合 Landau-Zener 跳跃概率等解析近似来处理太阳内部的 MSW...
Neutrino physics is a frontier and highly active interdisciplinary field in high energy physics. The Jiangmen Underground Neutrino Observatory (JUNO) is a medium-baseline, multi-purpose, large-scale neutrino experiment. The major goals are to determine the neutrino mass hierarchy by precisely measuring the energy spectrum of reactor neutrinos, and it is expected to achieve a 3sigma measurement...
Detector identifier and geometry management system plays an important role in every nuclear and particle physics experiment. Jiangmen Underground Neutrino Observatory~(JUNO), a large neutrino experiment whose design started in 2013, has completed detector construction and began data taking in 2025. In this poster, we describe the architecture and implementation of the identifier and geometry...
质量在 2 - 15 MeV 量级的惰性中微子可通过太阳 $^{8}\mathrm{B}$ 中微子混合产生,并部分衰变为 $\nu_{e}e^{+}e^{-}$。其通量和寿命由混合参数 $|U_{eH}|^2$ 和惰性中微子质量 $m_{\nu_H}$ 决定。根据惰性中微子的衰变产物,我们有两种探测方式:探测其在地球探测器中衰变产生的电子对或在探测器外衰变产生的 $\nu_e$。本研究中我们通过模拟得到两种探测方式在 500 吨探测器运行一年下的能谱以及角度分布,结合本底分别给出灵敏度并与现有实验约束比较。两种方式给出的灵敏度在 $(|U_{eH}|^2, m_{\nu_H})$ 空间中互补。
HUNT项目拟建设大规模水下中微子探测器,触发与数据处理流程是评估探测器可用性的重要环节。本报告将介绍HUNT项目背景、现有模拟数据处理流程及触发设计思路,并基于典型信号与背景样本讨论其在信号保留等方面的表现。初步研究表明,在当前模拟条件和算法假设下,现有流程对部分典型事例,尤其是级联型事例,表现出实现稳定触发和支持后续分析的潜力,也为HUNT采用20英寸PMT的方案在典型中微子事例中的可使用性提供了初步支持。
TAO (Taishan Antineutrino Observatory) 是江门中微子实验 (JUNO) 的卫星项目,是精确测量反应堆中微子能谱的前沿装置。TAO探测器距离反应堆44米,位于地平面以下9.6米,宇宙线流强较高。中心探测器 (CD) 外围反符合探测器 (VETO) 负责屏蔽天然放射性并标记宇宙线缪子。作为确保中微子探测精度的关键屏障,VETO的性能与效率直接决定了中微子事例挑选的纯度。本报告将介绍VETO探测器及muon效率分析,并监测探测器效率变化情况。
江门中微子实验(JUNO)的首要物理目标是测量中微子质量顺序和精确中微子振荡参数测量,具有测气中微子、超新星中微子、大气中微子等丰富物理测量目标。中心探测器(CD)部分包含大气中微子事例的测量,为进一步提高江门中微子实验的大气中微子统计量和测量精度,具有重要价值和意义。本报告目标介绍JUNO外层VETO系统特别是8英寸PMT系统,以及与其他子探测器进行关联分析结果。
刚刚建成的强流重离子加速器装置HIAF可以提供几个GeV能量的质子和重离子束流,为广泛的物理研究提供了良好的机遇,包括寻找超出标准模型的新粒子、新相互作用,检验CP等基本对称性,寻找新(奇特)强子态、奇特双重子态、新(多奇异)超核,强子、超核性质的精确测量,核物质相边界和相变临界点的发现和定位,等等。我们提议在HIAF高能终端建设惠州强子谱仪,简称HHaS。它由螺线管磁铁、硅像素径迹探测器、LGAD飞行时间探测器、切伦科夫光-闪烁光双读出电磁量能器构成,可以实现1MHz-100MHz的超高事例率、大接受度、多种粒子鉴别能力以及高动量、能量、位置分辨能力,从而满足上述丰富的物理研究需求,促进基于我国实验装置的中高能粒子物理与核物理研究发展。报告将介绍实验的概念设计和初步模拟结果等。
强相互作用与电磁相互作用是自然界两种基本相互作用,也是粲偶素衰变中最重要的两类贡献。基于SU(3)理论并结合实验分支比的间接计算表明,J/ψ衰变中的强-电磁相对相位普遍接近90°,而其他粲偶素(如ψ(2S)、ψ(3770))则呈现出其他可能的取值。目前,该相角是否具有普适性在理论上仍是一个悬而未决的问题,其取值对于理解“ρπ疑难”、“ψ(3770)-nonDDbar衰变”,以及粲偶素各类强子衰变分支比的测量均具有直接输入意义。BESIII实验利用扫描截面方法,对J/ψ、ψ(2S)及ψ(3770)能区若干强子末态的产生截面谱进行了测量,并从中直接提取了该相角。本报告将基于BESIII的扫描实验结果,对该相角问题进行讨论。
Jiangmen Underground Neutrino Observatory (JUNO) is a large-scale neutrino experiment situated in southern China, primarily dedicated to determining the neutrino mass ordering and exploring other key topics in neutrino physics. JUNO detector has finished detector commission and officially begun data taking on August 22, 2025. The Data Quality Monitoring (DQM) system plays an indispensable role...
In a quark-gluon plasma, the enormous total angular momentum generated by non-central collisions evolves over time through spin-orbit coupling interactions, eventually converting into the spin component and thereby inducing spin polarization of the particles.
Our work studies the contribution of the shear flow generated by non-equilibrium medium to the spin alignment of the vector meson J/ψ...
TAO中心探测器刻度主要包括增益(Gain)、时间偏移(Time offset)、暗噪声计数率(DCR)、相对光子探测效率(relative PDE)、外部光学串扰刻度(X-talk)。
The Taishan Anti-neutrino Observatory (TAO) is a satellite experiment of the Jiangmen Underground Neutrino Observatory (JUNO). It is located close to one of the cores of the Taishan nuclear power plant (NPP) and was built to provide a high resolution reference energy spectrum for the neutrino oscillations studies in JUNO.
Event display serves as an indispensable tool in high-energy physics...
Large neutrino telescopes offer unique opportunities to detect neutrinos from the next core-collapse supernova (CCSN), following the only observation in 1987. The TRopIcal DEep-sea Neutrino Telescope (TRIDENT), a next-generation detector in the South China Sea, is primarily designed for high-energy neutrinos but is also sensitive to MeV-scale bursts from nearby CCSNe. Such events induce a...
在台山反中微子实验(TAO)中,宇宙线μ子和它的次级产物是本底的主要来源;因此,对μ子的有效探测对降低本底事例至关重要。
TAO的反符合系统主要由水箱(WT)及顶部反符合探测器(TVT)构成。TVT由160条带波长位移光纤(WLS)的塑料闪烁体(96条200×20×2cm3、64条150×20×2cm3)组成,分为四层,每层40条塑闪交错排列。于2025年9月完成搭建,经调试后整体运行稳定,探测性能满足实验预期目标。
The infrared structure of gauge theories with chiral fermions remains largely unexplored. In this work we investigate the Bars--Yankielowicz class using the functional renormalisation group, building on recent developments in gauge--fermion systems that provide clear criteria for confinement and dynamical symmetry breaking.
We show that two distinct phases arise: one exhibiting both...
由钾-40衰变和铀-238、钍-232衰变链释放出的地球中微子可以充当探测地球内部化学组成的独特探针。本研究拓展了基于切伦科夫液体闪烁体的地球中微子方向性探测方案,使用中微子-电子弹性散射过程探测中微子信号,使用模拟得到了中微子信号方向重建的分辨率,并利用太阳角的筛选条件有效压低了太阳中微子本底。只考虑太阳中微子这一本征本底时,该方案预计在2.8千吨·年的曝光量下,实现钾-40地球中微子$3\sigma$显著度的探测灵敏度。本研究还探讨了基于该方案进行地球大尺度地质结构成像的可行性,并预计在10.6千吨·年的曝光量下以$3\sigma$的显著度排除地球中微子方向均匀分布的假设。
标准模型虽然取得了巨大成果,但仍未能回答反物质去哪了,暗物质是什么等重大科学问题,因此寻找新物理是目前粒子物理实验最重要的目标之一。稀有衰变是精确检验标准模型和间接寻找新物理的重要途径。LHCb实验利用海量质子-质子对撞数据能精确研究重味强子的稀有衰变,主要包括味道改变带电流过程、味道改变中性流过程和轻子普适性检验等间接寻找新物理信号,与直接寻找有效互补。
The search for astrophysical neutrinos is largely limited by atmospheric neutrinos, which act as the primary background. At high energies, the prompt component from charm-hadron decays is expected to overtake the conventional atmospheric flux, owing to its harder energy spectrum. However, this prompt flux has so far escaped experimental measurement, making it one of the leading sources of...
摘要:为了应对下一代长基线中微子振荡实验(如DUNE、Hyper-K)对系统误差的严苛要求,中微子-核子反应截面的精确测量成为关键。本文提出利用我国在建的强流重离子加速器装置(HIAF)中的高能碎片分离器(HFRS)作为π介子动量选择器,通过飞行衰变产生能量展宽仅为~5%的窄带中微子束。通过G4Beamline的模拟,对9.3 GeV质子和4.26...
High-energy astrophysical neutrinos provide a unique messenger for studying the origin of cosmic rays, making precise direction reconstruction a key task for neutrino telescopes. However, underwater neutrino detectors operate in optical backgrounds induced by PMT dark noise and radioactive decays, which challenge hit selection and track reconstruction, especially for the early-stage TRIDENT...
DAMPE (DArk Matter Particle Explorer) is a space-based particle detector launched in December 2015 to observe high-energy electrons, gamma rays, and cosmic rays. Secondary cosmic ray fluxes serve as key probes of the propagation and interaction of high-energy particles in the Galaxy. Spectral measurements of secondary nuclei, such as lithium, beryllium, boron, as well as their ratios to...
After fifteen years of operation on board the International Space Station, AMS has performed precise measurements of high-energy solar energetic particles (SEPs), mostly observed during the solar maxima of cycles 24 and 25. AMS has collected data on more than 60 high-energy SEP events accelerated during M- and X-class flares and associated with fast coronal mass ejections. AMS detects these...
Heavy flavor production serves as an ideal probe of the hadronization mechanism in the hot and dense QCD medium created in relativistic heavy-ion collisions. Heavy quarks acquire elliptic flow through strong coupling with the medium, making v2 a sensitive observable for probing the hadronization time. In this work, we study the production and elliptic flow of Ds and D0 mesons in Pb+Pb...
We present the properties of the flux of primary cosmic Ni nuclei in the rigidity range from 3 GV to 1.3 TV, based on 30,000 nuclei collected by Alpha Magnetic Spectrometer during 13.5 years of operation from May 2011 to November 2024. The rigidity dependence of the Ni/Fe flux ratio will be equally discussed.
电磁量能器(ECAL)作为AMS实验中高能电磁簇射测量和粒子鉴别的核心探测器,在电子/正电子能量测量、质子背景抑制、光子方向重建以及高能宇宙线物理分析中发挥关键作用。随着TeV能区统计量的积累,传统基于人工变量和多变量判别的方法在复杂三维簇射形态刻画、能量依赖性建模和极端背景抑制方面面临更高要求。本报告将介绍基于深度学习的AMS-ECAL重建方法研究进展。通过将ECAL的多层三维能量沉积信息转化为适合神经网络处理的图像化输入,并采用残差神经网络(ResNet)结构,可实现对电磁簇射轴方向、入射位置以及电子/质子粒子鉴别的端到端建模。该方法能够自动学习纵向和横向簇射发展特征,增强对高能电磁簇射拓扑结构的识别能力,并为独立于硅径迹探测器的量能器重建提供新的技术路径。这些研究对于提升AMS在高能正负电子谱、正电子超额、可能的暗物质或天体源信号搜索等物理测量中的分析能力具有重要意义。
AMS-02的精确测量揭示了带电宇宙线基本粒子的特性。在刚度绝对值~60到~500GV范围中,反质子与质子流强有着相同的刚度依赖关系。这一行为表明,相较传统理论中由宇宙线碰撞产生的次级反质子,高能反质子存在超出。同时,反质子流强与正电子流强在~60到~500GV能区中也表现出相同的刚度依赖关系。正电子/反质子流强之比与能量无关,比值大致为常数2。
We present the precision measurement of the daily proton and helium fluxes by AMS during 14.5 years of operation aboard the International Space Station. The measurements cover the rigidity ranges from 1 to 100 GV for protons and from 1.7 to 100 GV for helium. The observed fluxes exhibit variations on multiple time scales. On short time scales, recurrent periodicities of 27 are especially...
The DArk Matter Particle Explorer (DAMPE) is a satellite-borne cosmic particle detector which was launched on Dec. 17th, 2015 into a sun-synchronous orbit with the tilt angle of 97.4 degree. The high energy resolution and large geometric acceptance make the detector suitable for the cosmic ray electron (plus positron) measurement. In this work, the time-dependent electron flux was measured...
The modulation effect of cosmic-ray muon flux measured in underground laboratories with atmospheric temperature has been observed in early underground experiments. The muon event rate is positively correlated with atmospheric temperature changes, which can be explained by the related theories of Barrett, Gaisser, and others. However, at the Daya Bay Neutrino Experiment, a nonlinear phenomenon...
Next-generation neutrino telescopes offer a powerful probe of high-energy dark matter, a regime that remains largely unexplored. We forecast the sensitivity of TRIDENT to dark matter annihilation in the Galactic Centre over $10^3$ to $10^5$ GeV. The analysis is carried out with all-flavour neutrino interactions, showing that cascade-like events can offer a promising search channel,...
RELICS实验计划采用两相型液氙时间投影室(LXeTPC)探测反应堆中微子产生的中微子-原子核相干弹性散射信号(CE$\nu$NS)。为实现亚keV核反冲的探测灵敏度,必须将液氙中的电负性杂质浓度维持在足够低的水平,以避免信号衰减。为此,我们建立了一个能够定量描述探测器内液氙中杂质输运过程的纯度演化模型。该模型综合考虑了运行中循环、液化与气化等输运机制,用以评估实际操作与系统设计对纯化性能的影响。本报告将介绍如何利用两次原型机运行数据对该纯度模型进行构建与验证,并将其应用于未来RELICS探测器纯化性能的预测。
Angular correlations between heavy quarks provide an important way to study the quark–gluon plasma (QGP) created in high-energy heavy-ion collisions. Current LHC measurements have reported azimuthal correlations of muons from semileptonic heavy-quark decays in 5.02 TeV Pb+Pb and pp collisions, with $p_{T}^{\mu} > 4 GeV $ and $|\eta^{\mu}| < 2.4$.All $\Delta \phi $ distributions show a...
We investigate the $\pi^0\eta$ photoproduction off protons using a 4π electromagnetic calorimeter BGOegg at Spring-8 BL31LEP with a linearly polarized photon beam produced via laser Compton scattering in the energy region of 1.3−2.4 GeV. The conventional beam asymmetry $\Sigma$ is obtained with the quasi-two-body approach, while $I^c$ and $I^s$ are deduced via exploiting the full three-body...
集体流是研究相对论重离子碰撞早期动力学过程的重要可观测量,其中一阶集体流v1对高重子密度核物质状态方程具有较高敏感性。低温高密核物质测量谱仪(CEE)依托HIRFL-CSR平台建设,是我国首台运行于GeV能区的大型核物理实验装置,能够提供能量范围为0.4-1.1...
We have used the parton and hadron cascade model PACIAE together with the Dynamically Constrained Phase-space Coalescence model (DCPC) to study the $T_{cs0}^{*}(2870)^{0}$ production in $pp$ collision at $\sqrt{s}$ = 7 TeV, following the LHCb observation of $T_{cs0}^{*}(2870)^{0}$ in the $B^{-}\to D^{-}D^{0}K^{0}_{S}$ decays in $pp$ collisions at $\sqrt{s}$ = 7, 8, and 13 TeV [PRL...
The search for quark–gluon plasma (QGP)-like collectivity in small collision systems remains a central goal of high-energy nuclear physics. Recent results from O+O collisions suggest that strongly coupled, near-perfect-fluid behavior may emerge even in such small systems, motivating a detailed investigation of jet quenching in systems of reduced size. In this work, we study hadron and jet...
The High-Luminosity Large Hadron Collider (HL-LHC) is designed to achieve a total integrated luminosity of 3000 fb-1. This significantly increases the radiation exposure to detectors and raises the average number of pileup interactions per bunch crossing to 140–200, which is three to five times higher than current operational levels. To address the challenges posed by high radiation and...
PandaX实验是基于双相液氙时间投影室技术的暗物质直接探测实验,下一代PandaX-20T可容纳约 20 吨液氙、灵敏体积约 17 吨,尺寸较前代显著提升。在时间投影室中,漂移区电场均匀性是决定能量分辨率与径向位置重建精度的关键因素,位于场笼边缘处的电场整形环的合理配置对抑制边缘及角落电场畸变、维持全漂移区电场均匀性至关重要。本研究基于 COMSOL 建立与 PandaX-20T 设计尺寸一致的二维轴对称静电场模型,以 FieldSpread(FS)为优化指标,通过参数化扫描系统研究整形环数量、宽度、半径及位置对漂移区电场分布的影响,确定最优配置使中心、边缘及角落区域 FS 均降至最低,为探测器整形环设计提供直接参数依据。
High transverse momentum ($p_T$) jets provide a sensitive probe to the resolving power of the Quark-Gluon plasma (QGP) produced in heavy-ion collisions. In particular, understanding how the medium responds to multi-prong configurations inside jets is essential for a quantitative description of jet quenching and its manifestation in jet substructure sensitive observables.
In this work, we...
A search for a massless beyond-standard-model particle is performed in the decay Ξ^0->Λ+invisible using (1.0087±0.0044)10^10 J/ψ events collected with the BESIII detector at the BEPCII collider. No significant signal is observed, and the upper limit on the branching fraction is set to be B(Ξ^0->Λ+invisible)<2.310^-4 at the 90% confidence level. This is the first search for a flavor-changing...
We propose that the anisotropic particle distributions in heavy ion collisions can induce a non-vanishing spin alignment of vector meson. We investigate this effect in the production processes of $\phi$ and $K^{*0}$ mesons. For both $\phi$ and $K^{*0}$ produced via S wave scattering, a negative $\delta\rho_{00}$ of order $10^{-3}$ is observed, whose absolute value increases in a more...
为什么不同夸克的味量子数(包括同位旋I及其投影I3以及S,C,B∗ ,T,共6个)不同而且繁琐?为什么味量子数在弱相互作用下不守恒?为什么超荷Y是一个重子数和部分味量子数的混合量,在盖尔曼-西岛公式却与I3并列?等等。从对这些问题的思考出发,提出了费米子量子数F。F是费米子(包括夸克和轻子)的味相关相加性量子数,在弱、电磁、强相互作用下都守恒,并且关系式 Q/e=(F0+F)/2(F0为单位电弱荷,包含了重子数和轻子数)适用于所有费米子,比盖尔曼-西岛公式(只用于夸克)更具普遍性。弱相互作用选择定则之前只是经验的,现在能用F守恒推导出来,...
液氙探测器对介质纯度具有极高要求,探测器材料放气是氧、水等电负性杂质的重要来源,会影响电子寿命和电荷收集效率。本研究面向 RELICS 双相液氙 TPC 原型探测器,开展了关键材料放气率的系统测量,分别研究了材料在常温和低温条件下的放气行为,分析了温度变化对放气率的影响,并评估了真空烘烤处理对材料放气率的抑制效果。进一步地,将测得的放气率结果与液氙纯度演化模型进行对比,用于检验材料放气对探测器纯度变化的贡献。相关研究可为液氙探测器的材料选择、预处理工艺优化和纯度控制提供实验依据。