LHAASO观测和相关新物理研究

• Xiaojun Bi (IHEP)

TBD

Consequences of phase transitions happened during inflation

• Haipeng An (Tsinghua University)

TBD

Highlights of Recent Physics Results from the ATLAS experiment

• Yusheng Wu

This talk will present some of interesting physics results recently acheived by the ATLAS experiment. The focus will be on measurements of Standard Model processes and Higgs properties, but examples of new physics searches will be covered as well. Methodologies and possible future directions will also be discussed.

Higgs and beyond at the CMS experiment

• Xiaohu Sun

TBD

Family tree decomposition of cosmological correlators

• Xianyu Zhong-Zhi (Tsinghua University)

The correlation functions of large-scale fluctuations are crucial observables in modern cosmology. There have been considerable efforts in the analytical study of cosmological correlators in recent years. In this talk, I will introduce the basic structure of cosmological correlators and several analytical methods we recently proposed for computing them. In particular, I will describe the family tree decomposition of arbitrary nested time integrals. With this method, we largely solve the problem of analytical computation of massive tree amplitudes in dS and conformal scalar tree amplitudes in a power-law FRW universe.

Primordial black holes and non-Gaussianity in the gravitational-wave era

• Sai 赛 Wang 王 (IHEP-CAS)

近期脉冲星计时阵列合作组发现了纳赫兹引力波背景的关键证据。学术界掀起有关引力波源的诸多讨论，除超大质量黑洞外，宇宙学源也受到强烈关注。本报告将着重介绍次级引力波的研究进展。我们将探讨原初非高斯性对次级引力波的重要贡献，并在此基础上分析纳赫兹引力波探测数据，进而尝试解决原初黑洞的过量产生问题。进一步地，我们提出表征次级引力波各向异性的角功率谱可作为原初非高斯性的有力探针。我们预期引力波探针将在原初黑洞暗物质和宇宙起源研究中扮演重要角色。

耗散效应作为宇宙相变的新观测量

• Huaike Guo (University of Chinese Academy of Sciences)

宇宙一阶相变引力波提供了粒子物理研究的新手段，在国内和国际上得到了广泛的研究。 在这一报告中，我将介绍此前很少被考虑的相变中的耗散效应，并讨论强耗散效应下相 变图像及引力波发生的改变。

Primordial black hole formation in slow phase transitions

• Ke-Pan (柯盼) Xie (谢) (Beihang University)

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Indirect search for new physics at LHCb

• Jibo HE (University of Chinese Academy of Sciences)

In this talk, I will review indirect searches for new physics at LHCb.

伽玛对撞机及综合束流设施

• 永盛 黄 (中山大学)

Neutrino Mass Measurement with Cosmic Gravitational Focusing

• Shao-Feng (韶锋) Ge (葛) (Tsung-Dao Lee Institute (TDLI), Shanghai Jiao Tong University (SJTU))

We thoroughly explore the cosmic gravitational focusing of cosmic neutrino fluid (CνF) by dark matter (DM) halo using both general relativity for a point source of gravitational potential and Boltzmann equations for continuous overdensities. Derived in the most general way for both relativistic and non-relativistic neutrinos, our results show that the effect has fourth power dependence on the neutrino mass and temperature. With nonlinear mass dependence which is different from the cosmic microwave background (CMB) and large scale structure (LSS) observations, the cosmic gravitational focusing can provide an independent cosmological way of measuring the neutrino mass and ordering. We take DESI as an example to illustrate that the projected sensitivity as well as its synergy with existing terrestrial neutrino oscillation experiments and other cosmological observations can significantly improve the neutrino mass measurement.

超轻暗物质粒子唯象学研究

• Xiaoping Wang

TBD

AMS最新实验物理结果

• Zuhao Li (IHEP)

TBD

Probing Ultralight Dark Matter with Laser Interferometers in Space

• Yong Tang (University of Chinese Academy of Sciences)

Ultralight bosonic fields (ULBFs) are predicted by various theories beyond the standard model of particle physics and are viable candidates of cold dark matter. There have been increasing interests to search for the ULBFs in physical and astronomical experiments. In this paper, we investigate the sensitivity of several planned space-based gravitational-wave interferometers to ultralight scalar and vector fields. Using time-delay interferometry (TDI) to suppress the overwhelming laser frequency noise, we derive the averaged transfer functions of different TDI combinations to scalar and vector fields, and estimate the impacts of bosonic field's velocities. We obtain the sensitivity curves for LISA, Taiji and TianQin, and explore their projected constraints on the couplings between ULBFs and standard model particles, illustrating with the ULBFs as dark matter.

Axion Bose-Einstein Condensate

• Hong Zhang

Axions, or in general axion-like particles, are popular dark matter candidates. They could form Bose-Einstein condensate in our universe. In this talk, I will discuss two different types of condensates: axion stars and black-hole superradiantaxion clouds. These condensates could emit radio-frequency photons as well as gravitational waves. The unique signatures of these signals will also be discussed.

Neutrino Mass Sum Rules from Modular A4 Symmetry

• Oleg Popov

Modular symmetries offer a dynamic approach to understanding the flavour structure of leptonic mixing. Using the modular A4 flavour symmetry integrated in a type-II seesaw, we propose a simple and minimalistic model that restricts the neutrino oscillation parameter space and, most importantly, introduces a sum rule in the physical neutrino masses. When combined with the mass squared differences observed in neutrino oscillations, this sum rule determines the absolute neutrino mass scale. This has significant implications for cosmology, neutrinoless double beta decay experiments and direct neutrino mass measurements. In particular, the model predicts $\sum_i m_i \approx 0.1$ eV for both normal and inverted ordering, and thus can be fully probed by the current generation of cosmological probes in the upcoming years.

Evaluating Feynman integrals by hypergeometric function method

• Hai-Bin Zhang (Hebei University)

We evaluate Feynman integrals by hypergeometric function method.

Helicity amplitudes without gauge cancellation for electroweak processes

• Junmou Chen (Jinan University)

Multiple EW vector boson amplitudes are known to have bad energy behavior for individual Feynman diagrams, which causes many problems for numerical and theoretical analysis. Based on Goldstone equivalence theorem(GET), we introduce a new representation of Feynman rules that makes GET manifest, while reproduces the exact results of the amplitudes. The new helicity has no subtle gauge cancellation, every diagram has a specific physical interpretation, when the pole approaches on-shell. We implement this new Feynman rules into numerical codes of HELAS (Helicity Amplitude Subroutines) and study several process with the new HELAS.

电弱修正计算研究

• Chen Long-Bin

本次报告将介绍近期的电弱修正计算。

Electroweak corrections to double Higgs production at the LHC

• Huan-Yu Bi

We present the results for the complete next-to-leading order electroweak corrections to pp → HH at the Large Hadron Collider, focusing on the dominant gluon-gluon fusion process. While the corrections at the total cross-section level are approximately −4%, those near the energy of HH production threshold exceed +15%, and corrections at the high-energy region are around −10%, leading to a shape distortion for the differential distributions. Our findings substantially diminish the theoretical uncertainties associated with this pivotal process, providing valuable input for understanding the shape of the Higgs boson potential upon comparison with experimental measurements.

Bootstrapping the Chiral Anomaly at Large Nc

• Teng Ma (UCAS)

TBD

电弱相变动力学的精确计算

• Fa Peng Huang (Sun Yat-sen University)

TBD

近简并Z/Z'粒子系统的探测

• Yi-Lei Tang (中山大学)

通常文献中对于Z'粒子的探测都假定Z'与Z玻色子的共振峰相距甚远。当Z'与Z粒子近简并且可能有强烈混合时，文献中缺乏详细的讨论。在这种情况下，Z'和Z的共振峰可能很难分开，过去对撞机上的探测结论都失效了。针对这种情况，我们模拟了一种类似LEP的探测器，通过探测Z'-Z重叠共振峰的形状，讨论了这种探测器对于Z'粒子探测的敏感度。我们进一步以CEPC为例，讨论了有关探测器的敏感度。

X-ray polarimetric features of Gamma-ray Bursts across varied redshifts and hints for Axion-Like-Particles

• Feng Huang (Xiamen University)

The study of polarimetric features during the prompt phase of Gamma-ray Bursts (GRBs) has been essential for elucidating the debated emission mechanisms and gaining insight into the inner structure of GRBs. However, the potential impact of photon-Axion-Like-Particles (ALPs) mixing in extragalactic magnetic fields, leading to significant modifications in the initial polarization, has been overlooked in discussions concerning prompt phase constraints. In this article, we first examine the statistical characteristics of linear polarization degree ($\Pi_{L}$) in GRBs, utilizing data from updated polarimetric missions focusing on sub-MeV emissions. Our analysis, conducted with a restricted sample of GRBs spanning various redshifts, reveals a diverse distribution of $\Pi_{L}$, which currently shows no correlation with spectral parameters or properties of candidate host galaxies. Furthermore, we explore alternations to the initial $\Pi_{L}$ due to photon-ALP mixing within a domain-like structure of the intergalactic magnetic field (${\bf B}_{\rm IGM} $), considering various parameter sets associated with ALPs and ${\bf B}_{\rm IGM}$. With the existence of ALPs with mass $m_{a}$$~$$\lesssim$$~$$10^{-14}$$~$eV and photon-ALP coupling constant $g_{a\gamma}$$\simeq$$0.5\times10^{-11}$$~$GeV$^{-1}$, we show that for GRBs with redshifts above approximately 1, fully linearly polarized photons may experience a polarization reduction of up to $20\%$, whereas for unpolarized photons, the mixing can increase polarization by up to ~$40\%$. To ensure that the effect of mixing is small enough to be negligible, there is a strong constraint on the mixing term $\Delta_{a\gamma}$ should be less than $1.5\times 10^{-4}\rm Mpc^{-1}$. Currently, the number of GRBs with both sub-MeV polarization measurements and redshift confirmation remains very limited. Harf of the GRBs with available polarization data have a $\Pi_{L}$ of less than 30\%. Certification of redshift for this subset of GRBs would aid in further constraining the parameter space of low-mass ALPs or providing an independent means to determine the upper limit on ${\bf B}_{\rm IGM}$

Matter Asymmetry Genesis in the $Z_N$-companion Dark Matter Models

• Zhaofeng Kang

Ref.~\cite{Guo:2021rre} proposes a class of $Z_{N\geq 3}$-symmetric WIMP dark matter characterized by the semi-annihilation into the companion of dark matter, evading the stringent direct detection constraint. In this work, we point out that such kind of models naturally provides the three Sakharov elements necessary for dark matter asymmetry, and moreover this asymmetry can be transferred to the visible sector with a proper link to the leptonic or quark sector. In our minimal $Z_3$ example, the migration to the leptonic sector is via the asymmetric companion decay into neutrinos, and the lepton asymmetry can be further transferred to the quark sector for heavy dark matter ($\gtrsim 3$TeV). In particular, the CP violation parameter in our model is suppressed in the limit of static annihilation of dark matter, and we, for the first time, study the lift from thermal motion. We make a preliminary numerical analysis based on the Boltzmann equations, to find that both correct relic density of dark matter and baryon asymmetry can be accommodated.

Explaining the CDF W-mass shift and (g-2) mu in a Z prime scenario and its implications for the b to s llprocesses

• Xing-Bo Yuan (Central China Normal University)

TBD

The new physics implication for the recent Belle II observation of B^+ → K^+ νν ̄

• Xiao-Dong Ma (scnu)

no.

Possible Dark Matter Signals from White Dwarfs

• Jia-Shu Niu (Shanxi University)

In our galaxy, the white dwarfs (WDs) will inevitably capture the dark matter (DM) particles streaming through them, if there exist interactions between DM particles and nuclei/electrons. At the same time, these DM particles can also be evaporated by the nuclei/electrons in a WD if they have proper mass and the WD is not too cold. The evaporation of DM particles will lead to a faster cooling evolution than that predicted by the stellar evolution theory. In this work, we ascribe the faster cooling evolution of three observed WDs to the capture and evaporation of DM particles, and get the possible DM particle's mass and DM-electron cross section. The results are beyond the detection capabilities of current direct detection experiments and should be cross checked by more novel scenarios in the future.

Search for dark matter with XENONnT

• Jingqiang Ye (The Chinese University of Hong Kong, Shenzhen)

The XENONnT experiment, located in Laboratori Nazionali del Gran Sasso (LNGS), is a direct detection experiment designed to search for Weakly Interacting Massive Particles (WIMPs) using a dual-phase time projection chamber with 8.5 tonnes of xenon. The experiment began collecting science data in 2021 and is currently in operation. In its first science run (SR0), the experiment achieved an electronic recoil background of 15.8 events/(tonne-year-keV) below 30 keVee, establishing a new benchmark as the lowest background recorded in a dark matter detector. This achievement was made possible by reducing the amounts of radioactive Kr-85 and Rn-222 to an unprecedented low level. With the SR0 data, XENONnT has excluded new physics interpretations of the XENON1T excess and released the first WIMP search results. In this talk, I will present the first two results from XENONnT and the experiment's outlook.

$\alpha$ generalized no-scale inflation

• Lina Wu (Xi’an Technological University)

...

Analysis of the top-quark pair production via the $e^{+} e^{-}$ annihilation near the threshold region using the Principle of Maximum Conformality

• Jiang Yan (Chongqing University)

We present an improved analysis of the top-quark pair production via the process $ e^{+}e^{-} \to \gamma^{*} \to t\bar{t}$ near the threshold region up to next-to-next-to-next-to-leading order (N$^{3}$LO) QCD corrections. Near the threshold region, the top-quark velocity $v$ tends to zero, leading to Coulomb singularity. To achieve a reasonable prediction in the threshold region, we reconstruct the analytical expression for the Coulomb-terms up to N$^{3}$LO accuracy by using the PSLQ lgorithm, whose numerical values agree well with the previous N$^{3}$LO-level calculations. It is found that the N$^{3}$LO series still has sizable renormalization scale dependence, and to improve the precision of the series, we apply the Principle of Maximum Conformality to eliminate such scale dependence. After that, the Coulomb part is resummed into a Sommerfeld-Gamow-Sakharov factor, which finally leads to a much more reasonable behavior near the threshold region.

Bubble-free first-order phase transitions

• Yun Jiang (Sun Yat-sen University)

Traditionally a cosmic first-order phase transition proceeds by nucleating handful of bubbles through quantum tunneling. However, the presence of domain walls during the transition may greatly enrich the way phase transitions are completed. In this talk we develop the bubble-free mechanism, which constitutes a competing means of accomplishing the phase transition where bubble nucleation is inefficient or absolutely prohibited.

利用有效场论研究电弱相变

• 仁晖 覃 (重庆大学)

我们利用基于重整化理论的Dimensional Reduction来研究SMEFT模型下的一阶相变。我们展示了不同阶Dimensional Reduction计算结果对重整化能标的依赖性，以及化学势对该系统的影响。我们发现在两圈的精度下，Dimensional Reduction的结果对重整化能标的依赖性相对于树图和一圈而言可以忽略。此外，化学势对临界温度和成核温度的影响很弱，但会使相变强度和sphaleron energy明显降低。我们的结果显示，计算至两圈的Dimensional Reduction可以有效降低由重整化能标导致的理论不确定性，同时化学势的存在会明显影响实验对模型参数的限制。

Non-thermal leptogenesis from inflaton decay

• Xinyi Zhang (Hebei University)

There is growing evidence that the early Universe experienced inflationary expansion, yet no consensus has been drawn on the details. Meanwhile, neutrino physics is entering a precision era, making more information on masses and mixings available. We consider a neutrino path to the early Universe confronting the situation above. With right-handed neutrinos (RHNs) coupling to the inflaton, the baryon-antibaryon asymmetry may connect to inflationary observables, leading to a testable framework for particle physics and cosmology. We investigate non-thermal leptogenesis from inflaton decays in the type-I seesaw model, where a complex scalar is introduced to generate the Majorana mass of the RHNs. We find four characteristic limits with working conditions to identify them and show the combined parameter space.

Recent progress of Dark SHINE R&D

• Tong Sun (TDLI, SJTU)

Dark SHINE is a newly proposed fixed-target experiment at SHINE (Shanghai high repetition rate XFEL and extreme light facility, being the 1st hard X-ray FEL in China) under construction targeting completion in 2026. Dark SHINE aims to search for the new mediator, Dark Photon, bridging the Dark sector and the ordinary matter. In this work and presentation, we present the idea of this new project and 1st prospective study in search for Dark Photon decaying into light dark matter. It also provides the opportunity to incorporate broader scope of BSM search ideas such as ALP, utilizing the fixed-target experiment of this type.

Higgs properties and new physics beyond the SM

• Bin Yan (IHEP)

The discovery of the Higgs boson at the Large Hadron Collider (LHC) has opened a new era in particle physics. Precise measurements of the properties of the Higgs boson are crucial for addressing several fundamental questions in the field. These include understanding the mechanism behind electroweak symmetry breaking, unraveling the origin of particle masses, and exploring potential sources of CP violation that could explain the matter-antimatter asymmetry in the universe, and so on. In this talk, I will provide an overview of the recent advancements in Higgs physics, both within the framework of the Standard Model (SM) and beyond. By examining the latest research, we will gain insights into the properties and behavior of the Higgs boson, shedding light on the fundamental workings of the universe.

第六届简介

• 松 何 (吉林大学)