5 papers
Time-Domain Axion Searches with Magnetic White Dwarfs
Hong-Yi Zhang, Heng Bian, Zhao-Yu Zuo
Magnetic white dwarfs can convert photons into axions in their strong magnetic fields, with the conversion probability modulating the light curve as the star rotates. However, this…
Demagnifying gravitational lenses as probes of dark matter structures and nonminimal couplings to gravity
Hong-Yi Zhang
Magnification of total image fluxes is typically considered a defining feature of gravitational microlensing. In contrast, I will show that nonminimal couplings to gravity can gene…
Constraining Dark Photon Dark Matter with Radio Silence from Soliton Mergers around Supermassive Black Holes
Dorian W. P. Amaral, Enrico D. Schiappacasse, Hong-Yi Zhang
We place the first constraints on the dark matter fraction contained within dark photon solitons using the absence of their predicted radio-frequency signatures, or radio silence,…
Novel structures and collapse of solitons in nonminimally gravitating dark matter halos
Jiajun Chen, Hong-Yi Zhang
Ultralight dark matter simulations predict condensates with short-range correlation, known as solitons or boson stars, at the centers of dark matter halos. This paper investigates…
Unified view of scalar and vector dark matter solitons
Hong-Yi Zhang
The existence of solitons -- stable, long-lived, and localized field configurations -- is a generic prediction for ultralight dark matter. These solitons, known by various names su…