2025粒子物理标准模型及新物理精细计算研讨会

We compute all planar two-loop six-point massless integrals via canonical differential equations. The integral basis with uniform transcendentality is determined via the D-dimensional upgrading of dual conformal integrals and the Baikov representation analysis. The analytic boundary values are determined and all planar two-loop six-point massless planar are calculated as iterative integrals....

In this talk, I will present a Leptogenesis scenario, which does not need primordial B-L asymmetry in the early Universe, and does not need the existence of right-handed neutrinos. In this case, the baryon asymmetry is generated by the requirement that the electron Yukawa interction enters thermal equilibrium after the quench of the electroweak sphaleron.

We introduce a novel search strategy for heavy top-philic resonances that induce new contributions to four-top production at the LHC. We capitalize on recent advances in top-tagging performance to demonstrate that the final state, that is expected to be boosted based on current limits, can be fully reconstructed and exploited. Notably, our approach promises bounds on new physics cross sections...

The study of exotic gauge bosons beyond the Standard Model have always been of great interest. Future muon colliders will have a significant advantage in discovering exotic particles. We study the properties of $Z^\prime$ boson with the process of $\mu^+ \mu^- \rightarrow q \bar{q}$, $\mu^+ \mu^- \rightarrow l^+ l^-$, $\mu^+ \mu^- \rightarrow Z H$ and $\mu^+ \mu^- \rightarrow W^+ W^-$. ...

Here we discuss the 3pt celestial amplitude of two massive scalars and one massless scalar. In the massless limit $m\to 0$ for one of the massive scalars, the gamma function $\Gamma(1-\Delta)$ appears. By requiring the resulting amplitude to be well-defined, that is it goes to the 3pt amplitude of arXiv:2312.08597, the scaling dimension of this massive scalar has to be conformally soft...

The integration-by-parts (IBP) reduction is one of the bottleneck steps in the evaluation of multi-loop Feynman integrals. NeatIBP is a program based on the syzygy method for IBP reduction. It generates much smaller IBP systems compared to traditional Laporta's algorithm, which helps reduce the computation cost of IBP reduction. In this talk, I will present the new version of NeatIBP. It is...

We evaluate thethree-loop five-pointpentagon-box-box massless integral family in the dimensional regularization scheme, via canonical differential equation. We use tools fromcomputational algebraic geometryto enable the necessary integral reductions. The boundary values of the differential equation are determinedanalyticallyin the Euclidean region. To express the final...

The scalar mesons are established for a long time, but their nature is still an open question. In this paper, we investigate the potential of categorizing their $SU(3)_f$ representations via $J/\psi \to SV $and $\gamma S$, offering a criterion that may illuminate this issue. Here, $S (V)$ denotes scalar (vector) mesons. Using the $SU(3)_f$ symmetry with the current data, we find that...

In hidden-sector models, axion-like particles (ALPs) can couple to heavy neutral
leptons (HNLs), leading to rich phenomenologies. We study ALPs produced from D- and B-meson decays via quark-favor-violating couplings, and decaying exclusively into a pair of HNLs which mix with active neutrinos. The ALP can be either short- or long-lived, depending on the masses of the ALP and the HNL, as well...

Within the framework of Non-Relativistic Quantum Chromodynamics (NRQCD) factorization,
we calculate the next-to-leading order (NLO) perturbative QCD corrections to the form factors for
the semileptonic decays of Bc* into J/ψ via (axial-)vector and (axial-)tensor currents. We obtain the
complete analytical results for the form factors up to NLO, and provide their asymptotic expressions
in...

X（3872），作为四夸克的候选者，其产生和衰变等性质被实验和理论广泛研究。我们在NRQCD框架下，通过Higgs和弱玻色子衰变研究了双粲紧致四夸克态的间接产生机制，并分别在LHC和CEPC上预言了其分支比和产生率等。基于共线因子化，利用两种碎裂函数方法，我们对全粲四夸克态的间接产生性质也进行了深入的研究。通过此报告将详细介绍近期我们关于四夸克态间接产生的理论研究工作。

We investigate three intriguing anomalies within the framework of the general next-to-minimal supersymmetric standard model. These anomalies include a significant deviation of the experimental results for the muon anomalous magnetic moment from its standard model prediction, with a confidence level of 5.1σ; a joint observation by the CMS and ATLAS Collaborations of a diphoton excess with a...

Vector-like quarks (VLQs) are ubiquitous in many new physics models, such as grand unified theory, composite Higgs models, extra dimension theory, and so on. In minimal VLQ models, only seven types of representations can induce the mixing with standard model quarks. In non-minimal VLQ models, we can also introduce new scalar fields. The VLQ models can lead to rich phenomenology in electroweak...