The Coherent Elastic Neutrino-Nucleus Scattering (CEvNS) was predicted in 1974 but wasn't experimentally confirmed until 2017 due to its extremely low energy deposit, making detection challenging due to energy threshold and background levels. Liquid Xenon Time Projection Chambers (LXeTPCs) have shown excellence in dark matter searches and may serve as an ideal technology for detecting CEvNS....
Dark matter (DM) may be captured around a neutron star (NS) through DM-nucleon interactions. We observe that the enhancement of such capturing is particularly significant when DM-nucleon scattering cross-section depends on the relative velocity and/or momentum transfer. This increment could potentially lead to the formation of a black hole within the typical lifetime of the NS. As the black...
Motivated by the most recent measurement of tau polarization in $Z\to \tau^+\tau^-$ by CMS, we have introduced a new $U(1)_X$ gauge boson field X, which can have renormalizable kinetic mixing with the standard model $U(1)_Y$ gauge boson field Y.
In addition to the kinetic mixing of the dark photon, denoted as $\sigma$, there may also be mass mixing introduced by the additional Higgs doublet...
We present GKZ hypergeometric systems of four-loop vacuum Feynman integrals.
Phase transition gravitational waves could be a novel probe for fundamental physics in the near future. Hence, precise calculation of phase transition gravitational waves is essential to revealing many unresolved puzzles in our universe. I will discuss a framework that could allow us to omit some unnecessary approximations and give a relatively more accurate calculation of gravitational waves...
The seesaw mechanism is the most attractive mechanism to explain the small neutrino masses, which predicts the neutrinoless double beta decay (0νββ) of the nucleus. Thus the discovery of 0νββ is extremely important for future particle physics. However, the present data on the neutrino oscillation is not sufficient to predict the value of $m_{ee}$ as well as the neutrino mass $m^i_ν$. In this...
We fully explore the prospect of using the off $Z$-pole run at
future lepton colliders to probe the new physics (NP) beyond the Standard Model (SM) via dimension-6 four-fermion effective operators. With interference between the dimesion-6 operator and SM diagram contributions to the $e^+ e^- \rightarrow f \bar f$ scattering processes, the NP effects shows up at collision energy
off of the...
Within the standard model, transverse single spin asymmetries in electron elastic scatterings can only arise from multi-photon exchanges. The A4@MAMI collaboration has measured the beam transverse single spin asymmetry in electron-proton elastic scattering from 315 to 1508 MeV (Phys. Rev. Lett. 124, 122003 (2020)). The data are significantly different from theoretical calculations based on...
The representative effective field theories(EFTs) written in terms of Standard Model particles are Standard Model EFT(SMEFT) and Higgs EFT(HEFT). When we integrate out the heavy particles in the UV theory before electroweak symmetry breaking, it results in the SMEFT. On the other hand, if we integrate out the heavy particles taking into account the mass mixing in the symmetry-breaking phase,...
Dark matter is one of the biggest mysteries in physics and astronomy today. While multiple dark matter candidates have been proposed, such as the axion and primordial black holes (PBHs), the interplay between them is not well understood. In this talk, I will focus on the formation of axion minihalos around PBHs and the condensation of axion stars inside them, and reveal distinct morphological...
Cosmic strings, theoretical one-dimensional topological defects from the early universe, are a compelling source for studying dark matter production and gravitational wave (GW) emission. In this talk, I will focus on the production of gauge bosons and GW emission resulting from the decay of cosmic strings, discussing the constraints imposed by cosmological considerations. Specifically, I will...
We perform an analytic calculation of binary star evaporation rate under the gravitational potential from spatially extended dark solitons, and demonstrate that Milky Way’s wide binary star systems are susceptible to tidal perturbations from dark matter solitons of comparable and larger sizes. The GAIA data shows a sharp decrease of halo-like wide binaries at large separations, indicating...
Combination of recent measurements for $h \to Z \gamma$ from ALTLAS and CMS shows an excess that the ratio of the observed and standard model (SM) predicted branching ratios $\mu = (\sigma\cdot{\cal B})_{\mathrm{obs}}/(\sigma\cdot{\cal B})_{\mathrm{SM}}$ is $2.2\pm 0.7$. If confirmed, it is a signal of new physics (NP) beyond SM. We study NP explanation for this excess. In general, for a...
The 2HDM+S is the singlet extension of 2HDM, which can accommodate more physics potential beyond the SM. We summarize the type II 2HDM+S model with various Higgs potential structures, and discuss several scenarios with different mass hierarchy. In this study, we concentrate on the mass eigenstate of the 2HDM+S, and test the parameter space of Higgs mixing angles and masses against the...
Ultra-light Dark Matter (ULDM) is one of the most promising DM candidates. Due to the Bose
enhancement, we find the annihilation rate of the ULDM in the presence of background photon
radiation can be greatly enhanced and produce a distinctive reflected electromagnetic wave with an
angular frequency equal to the ULDM mass. We propose to utilize such stimulated annihilation
to probe the ULDM...
Future observation with next-generation large-area radio telescopes are expected to discover radio pulsars closely orbiting around Sagittarius A (Sgr A), the supermassive black hole (SMBH) in our Galactic Center (GC). Such a system can provide a unique laboratory for testing gravity theories , as well as the astrophysics around the GC. We will introduce our recent studies about prospects for...
Spherical black-hole (BH) solutions have been found in the bumblebee gravity where a vector field nonminimally couples to the Ricci tensor. We study dynamic (in)stability associated with the gravitational and vector perturbations of odd parity against these bumblebee BHs. Under the plane-wave approximation, we find that bumblebee BHs do not suffer ghost instability, but gradient instability...
We explore the theoretical description of oscillations in degenerate cases, presenting the formula for oscillation probability with neutrino oscillation as an illustrative example. We then apply the degenerate oscillation theory to study neutron-antineutron oscillations, calculating the constraints of the new model on oscillation parameters, such as mixing angles, in neutron stars. Our...
High-energy muon collider can play as an emitter of electroweak gauge bosons and thus leads to substantial vector boson scattering (VBS) processes. In this work, we investigate the production of heavy neutral lepton (HNL) $N$ and lepton number violation (LNV) signature through VBS at high-energy muon colliders. They provide clean and robust LNV signatures to tell the nature of Majorana HNLs...
Considering the hierarchical structure of fermionic masses and the fermionic flavor mixing puzzles in the Standard Model, we propose to relate them by the see-saw mechanism, i.e. only the third generation of quarks and charged leptons achieve the masses at the tree level, the first two generations achieves masses through the mixings with the third generation, and the neutrinos achieve tiny...
The Witten effect implies the dynamics of axion and magnetic monopole. The Cho-Maison monopole is a realistic electroweak monopole arisen in the Weinberg-Salam theory. This monopole of TeV scale mass motivates the dedicated search for electroweak monopole at colliders. In this work we investigate the implication of KSVZ axion to the electroweak magnetic monopole. We use the spherically...
In this talk, we will discuss production of gravitational waves in the early universe within a first order phase transition involving a hidden sector feebly coupled with the visible sector. Unlike most existing studies on GWs from hidden sectors, which assume a constant temperature ratio between the hidden and visible sectors (i.e., ξ=T_h/T=const), we adopt a more precise approach using...
PandaX-4T experiment is a dark matter direct detection experiment that employs a dual-phase time projection chamber with a sensitive volume containing 3.7 tonnes of liquid xenon. Since 2020, the PandaX-4T experiment has finished the data taking of run0 and run1 which has been used to test several dark matter models. In this talk, we will discuss the latest dark matter search results of the...
If the terrestrial environment is permeated by dark matter, the levitation experiences damping forces and fluctuations attributed to dark matter. This paper investigates levitodynamics with multiple stochastic forces, including thermal drag, photon recoil, feedback, etc., assuming that all of these forces adhere to the fluctuation-dissipation theorem. The ratio of total damping to the...
The possible Majorana nature of Neutrino is crucial for addressing profound questions such as the conservation of lepton number and the origins of the matter-antimatter asymmetry in the universe. Experimentally searching for Majorana neutrinos is one of the most important fields in the forefront of fundamental physics. The PandaX-4T detector, located in the China Jinping Underground Laboratory...
We investigates non-thermal leptogenesis from inflaton decays in the minimal extension of the canonical type-I seesaw model, where a complex singlet scalar $\phi$ is introduced to generate the Majorana masses of right-handed neutrinos (RHNs) and to play the role of inflaton. We systematically study non-thermal leptogenesis with the least model dependence. We give a general classification of...
Dark matter self-scattering is one of key ingredients for small-scale structure of the Universe, while dark matter annihilation is important for the indirect measurements. There is a strong correlation between the velocity-dependent self-scattering cross section and the Sommerfeld enhancement factor for the dark matter annihilation cross section. In this study, we formulate a direct relation...
We discuss possible ways of extending the Standard Model quantum chromodynamics theory (QCD) theory and realize a first-order phase transition at high temperatures above 1 GeV without running into current constraints from both heavy ion colliders and early cosmology. The phase transition is from a non-perturbative effect of the QCD and can have a great impact on the early universe, including...
We demonstrate, for the first time, the freeze-in dark matter, constituting 100% of the relic density can completely explain the Galactic 511 keV photon signal. In the talk, I will present two simple models for illustration. In both scenarios, the freeze-in mechanism generates the entire dark matter relic density, and thus any types of additional dark matter components produced from other...
We study graviton-photon conversion in potential ground-based experiments. From graviton to photon transition, we calculate the cross section of graviton-atom interaction in the presence of spherical atomic electric fields; the obtained results hold for graviton energy around 100 keV to 1 GeV, and would be enhanced along the coherent length in extremely high frequencies; thus it gives a chance...
本报告将讨论SU(2)矢量暗物质模型中拉矢量的一般构造方式，最终保证暗物质稳定性离散群的一般破缺方式，以及标量粒子的简并模式。
Scalar field dark matter (SFDM) comprised of ultralight (m ∼ $10^{−22}$ eV) bosonic particles has received significant attention as a viable alternative to Cold Dark Matter (CDM), as it approximates CDM on large scales (≳ 1 Mpc) while potentially resolving some of its small-scale problems via kpc-scale quantum interference. However, the basic SFDM model described by a free real field, a.k.a....
Anomalous transport phenomena, such as the chiral magnetic effect, are originated from the chiral anomaly of gauge theories and recently developed in hadron and condensed matter physics. They can also cause interesting phenomena in the early Universe when the chirality is a good conserved quantity at the temperature much higher than 100 TeV. An example is the chiral plasma instability, where...
We describe the SM quark/lepton masses in an SU(8) theory, where three-generational SM fermions are non-trivially embedded. A set of d=5 operators that break the emergent global symmetries in the chiral fermion sector due to the Planck scale effects are sufficient to generate the light SM quark/lepton masses as well as the CKM mixing pattern, with one single SM Higgs doublet in the spectrum.
We discuss the relation between the Higgs potential structure and primordial black hole (PBH) formations. Recently, it has been discussed that PBHs can be formed by first-order phase transitions at the early Universe. In this talk, we consider the PBH formation mechanism through delayed first-order phase transitions at the early Universe. If the phase transition is delayed, the large energy...
In view of both the latest LHCb measurement of $R_{K^{(*)}}$ and the new $2.7\sigma$ deviation reported by Belle II on $B^{+}\to K^{+}\nu\bar{\nu}$ decays, we present a fit to the $B$ meson anomalies for various one and two dimensional hypothesis including complex Wilson coefficients. We show in a model-independent way that the generic non-universal $U(1)^{\prime}$ extensions of the SM,...
The composite Higgs boson scenario assumes the existence of a new strongly coupled gauge sector with a softly broken approximate hyperflavor symmetry. At low energies the corresponding dynamics may be studied with help of the holographic techniques inspired by AdS/QCD. We present the bottom-up soft-wall holographic model that admits a first-order phase transition and, using a perturbation...
