9 papers
A hidden reionization prior biases cosmological inference
Zihan Wang, Huanyuan Shan
Precision cosmology assumes that cosmic reionization was a single smooth transition. We show that this assumption is in tension with current observations: the Planck optical depth,…
Steep Redshift Evolution of the Ionizing Escape Fraction at --: Empirical Constraints and Comparison with Simulations
Zihan Wang, Huanyuan Shan
The ionizing photon escape fraction governs cosmic reionization yet remains observationally unconstrained as a function of halo mass. We present the first empirical c…
The JWST early galaxy crisis resolved by a reionization degeneracy
Zihan Wang, Huanyuan Shan
JWST's discovery of unexpectedly bright galaxies has triggered claims that standard CDM cannot reproduce their abundances, while estimates of the ionizing escape fractio…
A structural degeneracy explains reionization tensions and limits dark matter constraints
Zihan Wang, Huanyuan Shan
Over the past decade, reionization studies have yielded persistent factor-of-two-to-five disagreements in the inferred ionizing escape fraction and peak star for…
Axion Star Bosenova in Axion Miniclusters
Zihang Wang, Yu Gao
Axionic dark matter can form structures known as miniclusters that host an axion star at their center. The axion star feeds on the host, and the axion star mass may grow beyond its…
Reionization Topology as a Probe of Self-Interacting Dark Matter
Zihan Wang
The topology of cosmic reionization, the sizes, shapes, and connectivity of ionized bubbles is a primary observable of next-generation 21\,cm experiments. We show that this topolog…