159 citations · 1.1k across the 29 of their papers we have counts for
16 papers · 1 filter
Radio Emission from High-Frequency Gravitational Wave Point Sources
Ethan Baker, Hongwan Liu
High-frequency gravitational waves (HFGWs) in the MHz to GHz regime can convert into radio photons in the presence of astrophysical magnetic fields through the inverse Gertsenshtei…
Inhomogeneous Energy Injection in the 21-cm Power Spectrum: Sensitivity to Dark Matter Decay
Yitian Sun, Joshua W. Foster, Hongwan Liu +2
The 21-cm signal provides a novel avenue to measure the thermal state of the universe during cosmic dawn and reionization (redshifts ), and thus to probe energy injecti…
The Terrestrial Density of Strongly-Coupled Relics
Asher Berlin, Hongwan Liu, Maxim Pospelov +1
The simplest cosmologies motivate the consideration of dark matter subcomponents that interact significantly with normal matter. Moreover, such strongly-coupled relics may have eva…
Anticipating a New-Physics Signal in Upcoming 21-cm Power Spectrum Observations
Rennan Barkana, Anastasia Fialkov, Hongwan Liu +1
Dark matter-baryon interactions can cool the baryonic fluid, which has been shown to modify the cosmological 21-cm global signal. We show that in a two-component dark sector with a…
Hints of dark photon dark matter from observations and hydrodynamical simulations of the low-redshift Lyman- forest
James S. Bolton, Andrea Caputo, Hongwan Liu +1
Recent work has suggested that an additional per baryon of heating in the intergalactic medium is needed to reconcile hydrodynamical simulations with Lyma…
A Stimulating Explanation of the Extragalactic Radio Background
Andrea Caputo, Hongwan Liu, Siddharth Mishra-Sharma +2
Despite an intense theoretical and experimental effort over the past decade, observations of the extragalactic radio background at multiple frequencies below 10 GHz are not underst…
Low-Energy Signals from the Formation of Dark Matter-Nuclear Bound States
Asher Berlin, Hongwan Liu, Maxim Pospelov +1
Dark matter particles may bind with nuclei if there exists an attractive force of sufficient strength. We show that a dark photon mediator of mass MeV that kineti…
Joint CMB and BBN Constraints on Light Dark Sectors with Dark Radiation
Cara Giovanetti, Mariangela Lisanti, Hongwan Liu +1
Dark sectors provide a compelling theoretical framework for thermally producing sub-GeV dark matter, and motivate an expansive new accelerator and direct-detection experimental pro…
New Thermal Relic Targets for Inelastic Vector-Portal Dark Matter
Patrick J. Fitzpatrick, Hongwan Liu, Tracy R. Slatyer +1
We examine the vector-portal inelastic dark matter (DM) model with DM mass and dark photon mass , in the `forbidden dark matter' regime where $1 \lesssim m_{A'}/m_χ\l…
New Pathways to the Relic Abundance of Vector-Portal Dark Matter
Patrick J. Fitzpatrick, Hongwan Liu, Tracy R. Slatyer +1
We fully explore the thermal freezeout histories of a vector-portal dark matter model, in the region of parameter space in which the ratio of masses of the dark photon …
Electromagnetic Signals of Inelastic Dark Matter Scattering
Masha Baryakhtar, Asher Berlin, Hongwan Liu +1
Light dark sectors in thermal contact with the Standard Model naturally produce the observed relic dark matter abundance and are the targets of a broad experimental search program.…
Reviving Millicharged Dark Matter for 21-cm Cosmology
Hongwan Liu, Nadav Joseph Outmezguine, Diego Redigolo +1
The existence of millicharged dark matter (mDM) can leave a measurable imprint on 21-cm cosmology through mDM-baryon scattering. However, the minimal scenario is severely constrain…
Dark Matter Energy Deposition and Production from the Table-Top to the Cosmos
Hongwan Liu
The discovery of nongravitational interactions between dark matter and the Standard Model would be an important step in unraveling the nature of dark matter. If such an interaction…
Searching for Axion Dark Matter with Birefringent Cavities
Hongwan Liu, Brodi D. Elwood, Matthew Evans +1
Axion-like particles are a broad class of dark matter candidates which are expected to behave as a coherent, classical field with a weak coupling to photons. Research into the dete…
Complementarity for Dark Sector Bound States
Gilly Elor, Hongwan Liu, Tracy R. Slatyer +1
We explore the possibility that bound states involving dark matter particles could be detected by resonance searches at the LHC, and the generic implications of such scenarios for…
Enabling Forbidden Dark Matter
James M. Cline, Hongwan Liu, Tracy R. Slatyer +1
The thermal relic density of dark matter is conventionally set by two-body annihilations. We point out that in many simple models, annihilations can play an important rol…