Scattering and decay processes of thermal bath particles in the early universe can dump relativistic axions in the primordial plasma. If produced with a significant abundance, their presence can leave observable signatures in cosmological observables probing both the early and the late universe. In this talk, I will focus on the QCD axion and I will present recent and significant improvements...
The axion potential is characterized by a slowly decaying potential with multiple periodic barriers due to non-perturbative effect. By controlling the motion of the axion(-like) field，it could provide a natural solution to the Higgs mass. In this talk I will discuss the dynamics of vacuum annihilation and gravitational waves produced from the axion potential, providing a new test of the...
Cosmic acceleration on the axion-saxion moduli spaces and the Swampland
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...
It is believed that axion is one of the natural candidates of the cold dark matters and will play the key role to solve the strong CP problem in standard model. However, the existence of the axion has not been verified, until now, although a series of experiments have been developed to probe its possible response. Focusing on the possible electromagnetic response of the axion in a laboratory...
Experimental Progress of APEX
In this work we study particles propagate in fractal paths and use fractal derivatives to extend the dynamic dimension of Quantum Field Theory. We construct the Lagrangian of fractal scalar, vector and spinor fields to obtain their propagators by path integral. Then we compute the typical tree level and one loop diagrams which correspond to QED cases. The calculations show the dimension...
In gauge mediation models with multiple spurion fields breaking SUSY and the R-symmetry separately, we show that it is possible to generate gaugino masses at one loop if the R-charge arrangement satisfies a certain condition. The resulting gaugino masses are calculated and suppressed by some power of the messenger mass scale. We present two simple examples to demonstrate this possibility, and...
We study the new observational effects of ultralight axion-like particles by the space-borne gravitational wave detector and the radio telescope. Taking the neutron star-black hole binary as an example, we demonstrate that the gravitational waveform could be obviously modified by the slow depletion of the axion cloud around the black hole formed through the superradiance process. We compare...
We study the probing prospects of cosmic ray boosted dark matter (DM) in the framework of simplified electron-philic dark photon model. Focusing on the dark matter and dark photon masses around keV ∼ MeV scale, we consider the bounds obtained from the XENON1T and Super-K experiments. The electron bound state effects are treated carefully in calculating the XENON1T constraint. As for the...
Axion-like particles (ALPs) have been studied in numerous experiments to search for their interactions, but most studies have focused on deriving bounds for the single coupling. However, in ultraviolet (UV) models, these couplings can appear simultaneously, and their interplay could have important implications for collider and beam dump searches. In this study, we investigate the concurrent...
A new type of four-point interaction, $W$-$\ell$-$\nu$-$a$, in an electroweak-violating scenario of axion-like particle (ALP) and lepton interactions plays a critical role in searching for ALPs from charged mesons and W boson decays because of the novel energy enhancements. Inspired by this interesting finding, we first proposed new t-channel processes for electrophilic ALPs (eALPs) which also...
The Type II seesaw mechanism is among the simplest extensions of the Standard Model accounting for neutrino masses. These are naturally induced by the vacuum expectation value (vev) of a scalar triplet coupling to the Standard Model Higgs and lepton doublets. In this talk, I will show that the "type-II majoron" - the pseudo Nambu-Goldstone boson that arises in this context if the lepton number...
We propose the generic no-scale inflation inspired from string theory compactifications. We consider the renormalizable superpotential of inflaton field $\varphi$ in general and the Kähler potentials with $\varphi$, as well as one, two, and three Kähler moduli. We study the spectral index and tensor-to-scalar ratio in details, and find the viable parameter spaces which are consistent with the...
Many attempts have been made to observe the decay of the Higgs boson to a photon and an invisible massless dark photon. For this decay to be potentially observable at the LHC, new mediators that communicate between the standard model and the dark photon must exist. In this Letter, we study bounds on such mediators coming from the Higgs signal strengths, oblique parameters, electric dipole...
In terms of quirk model and inelastic dark matter model, I will discuss the sensitivities of the FASER and FASER2 detectors.
Ref: https://arxiv.org/abs/2306.00641
Results from a wide range of searches targeting different experimental signatures with and without missing transverse momentum ($E^{miss}_{T}$) are used to constrain a Two-Higgs-Doublet Model (2HDM) with an additional pseudo-scalar mediating the interaction between ordinary and dark matter (2HDM+a). The analyses use up to 139 $fb^{−1}$ of proton-proton...
Quantum sensing has greatly improved the measurement accuracy of physical quantities such as electromagnetic fields, rotation, time, and gravity, which has brought revolutionary means to many frontier sciences such as verifying basic physical laws. My talk first introduces our developed spin-based metrology for ultra-sensitive weak magnetic field measurement. The quantum sensing system is...
If dark matter has a finite size, the intrinsic interaction responsible for the structure formation is inevitable from the perspective of dark matter self-scattering. To describe the circumstance in which the binding force realizes the finite size dark protons, we first use the Eikonal approximation to simplify the convoluted scattering between dark protons into the case at the $t=0$ limit....
I discuss the possibility of uncovering certain microscopic features of axions, for instance the UV origin of the axion field variable and the quality of PQ symmetry, through low energy observables such as the low energy axion couplings and the nucleon and atomic EDMs.
