159 citations · 1.1k across the 29 of their papers we have counts for
31 papers
Peering Beyond the Veil of Last Scattering: A View of the Universe with CMB Spectral Distortions
Bryce Cyr, Nabila Aghanim, Ethan Baker +37
The frequency spectrum of the cosmic microwave background is the most precise blackbody ever measured in nature, with deviations constrained at the level of almost one part per mil…
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…
spectroxide: A code package for computing cosmic microwave background spectral distortions
Ethan Baker, Hongwan Liu, Siddharth Mishra-Sharma
We present spectroxide, a code package for computing cosmic microwave background spectral distortions in which all lines of Rust code, Python interface, and ${\sim…
The DREAMS Project: Disentangling the Impact of Halo-to-Halo Variance and Baryonic Feedback on Milky Way Dark Matter Density Profiles
Alex M. Garcia, Jonah C. Rose, Paul Torrey +23
In this work, we utilize a new suite of Milky Way-mass halos from the DREAMS Project, simulated with Cold Dark Matter (CDM), to quantify the influence of baryon feedback and intrin…
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…
Birth of the first stars amidst decaying and annihilating dark matter
Wenzer Qin, Julian B. Munoz, Hongwan Liu +1
The first stars are expected to form through molecular-hydrogen (H) cooling, a channel that is especially sensitive to the thermal and ionization state of gas, and can thus act…
Exotic energy injection in the early universe II: CMB spectral distortions and constraints on light dark matter
Hongwan Liu, Wenzer Qin, Gregory W. Ridgway +1
We calculate the post-recombination contribution to the Cosmic Microwave Background (CMB) spectral distortion due to general exotic energy injections, including dark matter (DM) de…
Exotic energy injection in the early universe I: a novel treatment for low-energy electrons and photons
Hongwan Liu, Wenzer Qin, Gregory W. Ridgway +1
Decaying or annihilating dark matter and other exotic energy injections can modify the spectrum of the universe's photon bath, resulting in e.g. new contributions to spectral disto…
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…
Revealing the Milky Way's Most Recent Major Merger with a Gaia EDR3 Catalog of Machine-Learned Line-of-Sight Velocities
Adriana Dropulic, Hongwan Liu, Bryan Ostdiek +1
Machine learning can play a powerful role in inferring missing line-of-sight velocities from astrometry in surveys such as Gaia. In this paper, we apply a neural network to Gaia Ea…
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…
Machine Learning the 6th Dimension: Stellar Radial Velocities from 5D Phase-Space Correlations
Adriana Dropulic, Bryan Ostdiek, Laura J. Chang +3
The Gaia satellite will observe the positions and velocities of over a billion Milky Way stars. In the early data releases, the majority of observed stars do not have complete 6D p…
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 …
Edges and Endpoints in 21-cm Observations from Resonant Photon Production
Andrea Caputo, Hongwan Liu, Siddharth Mishra-Sharma +3
We introduce a novel class of signatures---spectral edges and endpoints---in 21-cm measurements resulting from interactions between the standard and dark sectors. Within the contex…
Lyman- Constraints on Cosmic Heating from Dark Matter Annihilation and Decay
Hongwan Liu, Wenzer Qin, Gregory W. Ridgway +1
We derive new constraints on models of decaying and annihilating dark matter (DM) by requiring that the energy injected into the intergalactic medium (IGM) not overheat it at late…
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.…
Modeling Dark Photon Oscillations in Our Inhomogeneous Universe
Andrea Caputo, Hongwan Liu, Siddharth Mishra-Sharma +1
A dark photon may kinetically mix with the Standard Model photon, leading to observable cosmological signatures. The mixing is resonantly enhanced when the dark photon mass matches…
Dark Photon Oscillations in Our Inhomogeneous Universe
Andrea Caputo, Hongwan Liu, Siddharth Mishra-Sharma +1
A dark photon may kinetically mix with the ordinary photon, inducing oscillations with observable imprints on cosmology. Oscillations are resonantly enhanced if the dark photon mas…
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…