3 papers
astro-ph.GA2025
Discovery of two little red dots transitioning into quasars
Shuqi Fu, Zijian Zhang, Danyang Jiang +9
James Webb Space Telescope (JWST) has uncovered a new population of compact objects that show a unique V-shaped spectral energy distribution (SED) in the UV and optical wavelength…
astro-ph.GA2025
AGN ruled out as the dominant source of cosmic reionization
Danyang Jiang, Linhua Jiang, Shengxiu Sun +2
Cosmic reionization represents the latest phase transition in the Universe, when the Lyman continuum (LyC) photons turned the intergalactic medium (IGM) from neutral to highly ioni…
astro-ph.GA2024
No Redshift Evolution in the Fe II/Mg II Flux Ratios of Quasars across Cosmic Time
Danyang Jiang, Masafusa Onoue, Linhua Jiang +13
The Fe II/Mg II emission line flux ratio in quasar spectra serves as a proxy for the relative Fe to alpha-element abundances in the broad line regions of quasars. Due to the expect…