本讲座以强相互作用物质相变的观点简要讨论可见物质粒子及其质量的起源，包括由其基本现象归结为相变的物理机制、强关联非微扰系统相变的判据、以及相关研究的进展现状。
Some recent progresses will be introduced from the LHC CMS experiment on multi-boson physics, including, e.g., studying anomalous couplings from Same-Sign WWH, probing boosted Higgs through the WW decay channel, and searching for diboson resonances such as Higgs plus a photon.
The discovery of the Higgs boson has opened a new window into physics beyond the Standard Model. In this talk, I will discuss how the Higgs serves as a unique tool to probe the Dark Sector. I will cover three complementary strategies: constraining Dark Matter models via precision Higgs coupling measurements, performing direct Higgs portal searches, and exploring extended Higgs sectors that...
Higgs decaying to LLPs is an important part of the LLP search. In the past decade, ATLAS has established a comprehensive search programme covering a wide range of lifetimes. Due to the reconstruction and triggering challenges, dedicated analysis strategies have to be crafted, often resulting in analyses optimised for a very particular phase space. I will give a chronical review of how ATLAS...
In this talk we present a phenomenological search for exotic Higgs decays to light BSM particles at future muon colliders.
Extra-dimensions are a very interesting tool to address various missing parts of the Standard Model of particle physics. When one extra-dimension is added, a compactification based on a orbifold is required to ensure a chiral spectrum for the fermions. It also allows mechanisms to consistently break the bulk gauge group. Symmetry breaking on orbifolds can be understood in two different ways:...
The ATLAS and CMS experiments are unique drivers of our fundamental understanding of nature at the energy frontier. In this contribution to the update of the European Strategy for Particle Physics, we update the physics reach of these experiments at the High-Luminosity LHC (HL-LHC) in a few key areas where they will dominate the state-of-the-art for decades to come.
In this talk, we present our recent work at the frontier of multi-loop Feynman integrals and scattering amplitudes for precision physics. We have analytically computed two-loop six-point and three-loop five-point integrals, which represent the current state of the art in analytic Feynman integrals. Using these results and new reduction tools based on algebraic geometry, we have calculated the...
In this talk I would like to introduce the state-of-the-art parton level event generator NNLOJET and its application to precision phenomenology of the Higgs boson. The main theory uncertainties of the Higgs boson production at hadron collider are from the parton distribution functions and determination of the strong coupling alpha_s. We have made NNLO QCD accurate PDF grids to help improve...
Parameters in an effective field theory can be subject to certain positivity bounds if one requires a UV completion that obeys the fundamental principles of quantum field theory. These bounds are relatively straightforward at the tree level, but would become more obscure when loop effects are important. In this talk, I will discuss the impacts of loop contributions to the interpretation of...
We explore the surviving parameter space for sub-GeV thermal Dark Matter (DM) within Higgs-portal models, analyzing both a minimal Majorana DM scenario with a singlet scalar mediator and leptophilic DM scenarios. These light DM candidates face severe constraints from the observed relic density, Cosmic Microwave Background (CMB) measurements, and direct detection experiments. Our comprehensive...
I will introduce cosmological and gravitational-wave aspects of phase-transition phenomenology, including bubble nucleation and expansion dynamics, gravitational-wave generations, curvature perturbations, primordial black holes, and, in particular, the induced gravitational waves from primordial gravitational collapse at non-linear and non-perturbative levels.
In this talk, I will present the physics induced by the electroweak symmetry non-restoration (ESNR) in the early universe. I will show that ESNR may trigger SU(3)_C symmetry breaking and restoration. In addition, ESNR can also trigger the Leptogenesis without requiring any B-L violation.
In this talk, we will discuss the potential of investigating quantum entanglement effects at Higgs factory.
Long-lived particles (LLPs) originating from decays of Standard-Model-like or beyond-the-Standard-Model Higgs bosons are often featured with signatures of displaced vertices (DVs) and jets at colliders. In this work, we show that a recent ATLAS search for DVs plus jets, with its recast implementation, can efficiently place bounds on such hadronically or semileptonically decaying LLPs. In...
We present a supersymmetric Pati-Salam model with small representations as a potential candidate for physics beyond the Standard Model. The model features a Higgs sector with bifundamental fields $H_R+\bar H_R=(4,1,2)+(\bar 4,1,2)$, $H_L+\bar H_L=(4,2,1)+(\bar 4,2,1)$ as well as a pair of bi-doublet fields $h_a=(1,2,2)$ where $ a=1,2$, with three families of fermions accommodated in $...
We derive a set of linear UV unitarity conditions that go beyond positivity and are easy to implement in an optimization scheme with dispersion relations in a multi-field EFT. We apply it to Higgs self scattering and compare the newly obtained upper bounds with the traditional perturbative unitarity bounds from within the EFT, and discuss some phenomenological implications of the two-sided...
The Next-to-Two-Higgs-Doublet model (N2HDM) has a rich vacuum structure where multiple electroweak (EW) breaking minima, as well as CP and electric-charge breaking minima, can coexist. These minima can be deeper than the electroweak vacuum $v_{𝑒𝑤} \approx 246$ GeV of our universe, making our vacuum metastable. In such a case, one needs to calculate the tunneling rate from the EW vacuum to the...
Ref. ATLAS-CONF-2025-012
This note presents a combination of searches for Higgs boson pair (HH) production performed by the ATLAS and CMS Collaborations using proton-proton collision data sets recorded at $\sqrt{s}$ = 13 TeV at the LHC Run 2, corresponding to integrated luminosities ranging between 126 and 140 fb$^{-1}$. The upper limit at the 95% confidence level on the total HH production...
Recent measurements of single top-Higgs (tH) production at the LHC show consistent excesses above Standard Model predictions across multiple decay channels. While still statistically limited, these observations are intriguing given tH's unique sensitivity to the relative sign between top Yukawa and W boson couplings. This talk summarizes the current experimental landscape, and ongoing...
I will present a new jet-free strategy for the $HH \to 4b$ search at the LHC that enhances sensitivity by more than a factor of five compared with current approaches. The method uses all-particle inputs to jointly identify $h_1 h_2 \to 4b$ across variable Higgs-candidate masses and to estimate $(m_{h_1}, m_{h_2})$ via a mass-decorrelated multiclass classifier. A key feature is that the $HH$...
The strong CP problem remains one of the most important unresolved issues in the Standard Model. Spontaneous CP violation (SCPV) is a promising approach to the problem by assuming that CP is an exact symmetry of the Lagrangian but broken spontaneously at the vacuum, which enables the generation of the observed Cabibbo-Kobayashi-Maskawa (CKM) phase without reintroducing a nonzero strong CP...
GUTs unify quarks and leptons into same representations and predict correlations between their masses and mixing. We take new data of JUNO and perform numerical scans to explore the flavor space compatible with data in SO(10) GUTs. The quark-lepton correlation shows the preference of normal ordering for light neutrino masses, predicts favored region of the CP-violating phase in neutrino...
CP4 3HDM is a three-Higgs-doublet model based on the CP symmetry of order 4 (CP4) without any accidental symmetries. When exploring the scalar and Yukawa sector phenomenon of this model, the usual scan procedure is computationally time-consuming and inefficient. A much better scanning procedure, which we call the inversion, is to identify a set of crucial physical observables, to use them as...
The hot early Universe must have evolved through phase transitions around the electroweak epoch. In multi-Higgs models, this evolution could be much more intricate than a single-step EWPT. In this talk, I will discuss a peculiar regime in the two-Higgs-doublet model, in which thermal evolution of the early Universe passes through an intermediate phase with a charge-breaking vacuum. Remarkably,...
ATLAS and CMS experiments have confirmed Higgs boson’s role in giving mass to the weak bosons and 3rd generation charged fermions. However, whether the other generations of fermions acquire mass through the same mechanism remains an open question. The Higgs boson’s decay to a pair of muons provides a direct probe of its Yukawa coupling to second-generation fermions. In this talk, I will...
