41 citations · 152 across the 22 of their papers we have counts for
23 papers
Cross-correlating Squared kSZ and HI Intensity Fields: A Map-level ACT--MeerKAT Forecast
Yu-Er Jiang, Yun Liu, Yan Gong +5
The kinetic Sunyaev--Zel'dovich (kSZ) effect probes the line-of-sight momentum of free electrons, but its blackbody spectrum and velocity-dependent sign make it difficult to isolat…
Constraints on Axion-like Dark Matter from Cosmic Birefringence with a Polarization Array of Repeating Fast Radio Bursts
Xiaohui Liu, Zi-Yan Yuwen, Yun-Long Zhang +5
Axion-like dark matter (ALDM) is a well-motivated dark matter candidate whose Chern-Simons coupling to photons can induce cosmic birefringence, producing temporal oscillations and…
Cosmological Vacuum Decays from Schwinger-Keldysh Formalism
Zi-Yan Yuwen
In this work, we take a first step to a stochastic real-time description of the vacuum phase transitions in a radiation-dominated FLRW universe from the Schwinger-Keldysh formalism…
Primordial black hole formation in bulk-viscous cosmology
Zi-Yan Yuwen, Cristian Joana, Shao-Jiang Wang +1
We investigate primordial black hole (PBH) formation in a cosmological background with bulk viscosity. Using numerical simulations, we determine the collapse threshold and the resu…
The MeerKAT Thousand-Pulsar Polarisation Array II: Searches for Ultralight Axion-Like Dark Matter
Zi-Yan Yuwen, Michael Sarkis, Yin-Zhe Ma +4
We construct Pulsar Polarisation Arrays (PPA), using regular pulsars monitored in MeerKAT's Thousand Pulsar Array (TPA) Programme, to search for Axion-like Dark Matter (ALDM) withi…
The MeerKAT Thousand-Pulsar Polarization Array I: Properties of the Polarization and Rotation Measure Time Series Data
Michael Sarkis, Zi-Yan Yuwen, Yin-Zhe Ma +4
The polarimetry of recent pulsar observations has provided a wealth of observational data with which to test physical theories of emission mechanisms, radiative transfer and even t…
Vacuum bubbles from cosmic ripples
Zi-Yan Yuwen, Rong-Gen Cai, Shao-Jiang Wang
We investigate vacuum decays in the early Universe in the presence of curvature perturbations. For sufficiently large perturbations associated with over-densities, we find that the…
Squared-field cross-correlation between kinetic Sunyaev-Zel'dovich effect and 21-cm intensity mapping
Zi-Yan Yuwen, Yu-Er Jiang, Yin-Zhe Ma +3
Neutral hydrogen (HI) 21-cm intensity mapping is an effective method to track the distribution of baryonic matter, and extract astrophysical and cosmological information. The 21-cm…
Acoustic gravitational waves from primordial curvature perturbations
Zhuan Ning, Zi-Yan Yuwen, Xiang-Xi Zeng +2
Standard perturbative calculations of scalar-induced gravitational waves (SIGWs) have neglected nonperturbative effects in the large-amplitude regime. We develop a hybrid numerical…
Primordial Black Holes from Primordial Voids
Cristian Joana, Zi-Yan Yuwen
Primordial black holes (PBHs) are a compelling dark matter candidate and a unique probe of small-scale cosmological fluctuations. Their formation is usually attributed to large pos…
Cosmological Prediction from the joint observation of MeerKAT and CSST at = 0.4 1.2
Yu-Er Jiang, Yan Gong, Qi Xiong +10
Cross-correlating neutral hydrogen (HI) 21cm intensity mapping with galaxy surveys provides an effective probe of astrophysical and cosmological information. This work presents a c…
Sound waves from primordial black hole formations
Zhuan Ning, Xiang-Xi Zeng, Zi-Yan Yuwen +3
We present a numerical investigation of primordial black hole (PBH) formation from super-horizon curvature perturbations and the subsequent generation and propagation of sound wave…
Relic gravitational waves from primordial gravitational collapses
Xiang-Xi Zeng, Zhuan Ning, Zi-Yan Yuwen +3
A large primordial density perturbation of the Hubble scale will gravitationally collapse, generating an outgoing sound shell, whether or not a primordial black hole (PBH) is forme…
Gravitational waves from vacuum bubbles: Ultraviolet dependence on wall thickness
Jun-Chen Wang, Shao-Jiang Wang, Zi-Yan Yuwen
The gravitational wave (GW) spectrum from the first-order phase transition can be characterized by a few phenomenological parameters but with high degeneracies in model/data distin…
Anisotropies of cosmological gravitational wave backgrounds in non-flat spacetime
Rong-Gen Cai, Shao-Jiang Wang, Zi-Yan Yuwen +1
Recent reports of stochastic gravitational wave background from four independent pulsar-timing-array collaborations have renewed the interest in the cosmological gravitational wave…
Bubble wall velocity from number density current in (non)equilibrium
Zi-Yan Yuwen, Jun-Chen Wang, Shao-Jiang Wang
Cosmological first-order phase transitions (FOPTs) serve as comprehensive probes into our early Universe with associated generations of stochastic gravitational waves and superhori…
Bubbles kick off primordial black holes to form more binaries
Zi-Yan Yuwen, Cristian Joana, Shao-Jiang Wang +1
Primordial black holes (PBHs) may form before cosmological first-order phase transitions, leading to inevitable collisions between PBHs and bubble walls. In this Letter, we have si…
General bubble expansion at strong coupling
Jun-Chen Wang, Zi-Yan Yuwen, Yu-Shi Hao +1
The strongly coupled system like the quark-hadron transition (if it is of first order) is becoming an active play yard for the physics of cosmological first-order phase transitions…
General backreaction force of cosmological bubble expansion
Jun-Chen Wang, Zi-Yan Yuwen, Yu-Shi Hao +1
The gravitational-wave energy-density spectra from cosmological first-order phase transitions crucially depend on the terminal wall velocity of asymptotic bubble expansion when the…
Hydrodynamic sound shell model
Rong-Gen Cai, Shao-Jiang Wang, Zi-Yan Yuwen
For a cosmological first-order phase transition in the early Universe, the associated stochastic gravitational wave background is usually dominated by sound waves from plasma fluid…
Bubble expansion at strong coupling
Li Li, Shao-Jiang Wang, Zi-Yan Yuwen
The cosmological first-order phase transition (FOPT) can be of strong dynamics but with its bubble wall velocity difficult to be determined due to lack of detailed collision terms.…
The energy budget of cosmological first-order phase transitions beyond the bag equation of state
Shao-Jiang Wang, Zi-Yan Yuwen
The stochastic gravitational-wave backgrounds (SGWBs) from the cosmological first-order phase transitions (FOPTs) serve as a promising probe for the new physics beyond the standard…
Hydrodynamic backreaction force of cosmological bubble expansion
Shao-Jiang Wang, Zi-Yan Yuwen
As a promising probe for the new physics beyond the standard model of particle physics in the early Universe, the predictions for the stochastic gravitational wave background from…