activity
20112026
most citedDark Photon Dark Matter Produced by Axion Oscillations

212 citations · 1.6k across the 40 of their papers we have counts for

collaborators

41 papers

hep-ph2026

Cosmic Birefringence and Axiogenesis

Raymond T. Co, Lawrence J. Hall, Keisuke Harigaya +1

Recent analyses of Planck and ACT CMB data report a hint of isotropic cosmic birefringence (), corresponding to a parity-violating rotation of pol…

hep-ph2025

Dark Matter and Baryon Asymmetry from Monopole-Axion Interactions

Raymond T. Co, Keisuke Harigaya, Isaac R. Wang +1

We introduce a novel mechanism where the kinetic energy of a rotating axion can be dissipated by the interactions with dark magnetic monopoles. This mechanism leads to a framework…

hep-ph2025

Enhanced Matter Power Spectrum from Axion Kination after Big Bang Nucleosynthesis

Raymond T. Co, Nicolas Fernandez, Akshay Ghalsasi +2

Despite stringent constraints from Big Bang Nucleosynthesis (BBN) and cosmic microwave background (CMB) observations, it is still possible for well-motivated particle physics model…

hep-ph2025★ 8 cited

Acoustic Misalignment Mechanism for Axion Dark Matter

Arushi Bodas, Raymond T. Co, Akshay Ghalsasi +2

A rotation in the field space of a complex scalar field corresponds to a Bose-Einstein condensation of charges. We point out that fluctuations in this rotating condensate ex…

hep-ph2024

Axion baryogenesis puts a new spin on the Hubble tension

Raymond T. Co, Nicolas Fernandez, Akshay Ghalsasi +2

We show that a rotating axion field that makes a transition from a matter-like equation of state to a kination-like equation of state around the epoch of recombination can signific…

hep-ph2024

Lepto-axiogenesis with light right-handed neutrinos

Patrick Barnes, Raymond T. Co, Keisuke Harigaya +1

We study lepto-axiogenesis in theories where the right-handed neutrino is light enough that its dynamics affect the determination of the baryon asymmetry. When compared with theori…

hep-ph2023

Axion cogenesis without isocurvature perturbations

Raymond T. Co, Masaki Yamada

Axion rotations can simultaneously explain the dark matter abundance and the baryon asymmetry of the Universe by kinetic misalignment and axiogenesis. We consider a scenario in whi…

hep-ph2022★ 57 cited

Gravity as a Portal to Reheating, Leptogenesis and Dark Matter

Basabendu Barman, Simon Cléry, Raymond T. Co +2

We show that a minimal scenario, utilizing only the graviton as an intermediate messenger between the inflaton, the dark sector and the Standard Model (SM), is able to generate $si…

hep-ph2022★ 10 cited

Baryogenesis from Decaying Magnetic Helicity in Axiogenesis

Raymond T. Co, Valerie Domcke, Keisuke Harigaya

Generating axion dark matter through the kinetic misalignment mechanism implies the generation of large asymmetries for Standard Model fermions in the early universe. Even if these…

hep-ph2022★ 22 cited

Enhancing Searches for Heavy QCD Axions via Dimuon Final States

Raymond T. Co, Soubhik Kumar, Zhen Liu

Heavy QCD axions are well-motivated extensions of the QCD axion that address the quality problem while still solving the strong CP problem. Owing to the gluon coupling, critical fo…

hep-ph2022★ 16 cited

Lepto-axiogenesis and the scale of supersymmetry

Patrick Barnes, Raymond T. Co, Keisuke Harigaya +1

If the Peccei-Quinn field containing the QCD axion undergoes rotations in the early universe, the dimension-five operator responsible for neutrino masses can generate a lepton asym…

hep-ex2022★ 18 cited

First Constraints on Heavy QCD Axions with a Liquid Argon Time Projection Chamber using the ArgoNeuT Experiment

ArgoNeuT Collaboration, R. Acciarri, C. Adams +22

We present the results of a search for heavy QCD axions performed by the ArgoNeuT experiment at Fermilab. We search for heavy axions produced in the NuMI neutrino beam target and a…

hep-ph2022★ 6 cited

Discovery potential for split supersymmetry with thermal dark matter

Raymond T. Co, Aaron Pierce, Benjamin Sheff +1

Supersymmetric extensions of the Standard Model with scalar superpartners above 10 TeV are well motivated since the Higgs boson mass can be explained by quantum corrections while m…

hep-ph2022★ 15 cited

Axiogenesis with a Heavy QCD Axion

Raymond T. Co, Tony Gherghetta, Keisuke Harigaya

We demonstrate that the observed cosmological excess of matter over antimatter may originate from a heavy QCD axion that solves the strong CP problem but has a mass much larger tha…

hep-ph2022

Inflationary Gravitational Leptogenesis

Raymond T. Co, Yann Mambrini, Keith A. Olive

We consider the generation of the baryon asymmetry in models with right-handed neutrinos produced through gravitational scattering of the inflaton during reheating. The right-hande…

hep-ex2022★ 56 cited

New Horizons: Scalar and Vector Ultralight Dark Matter

D. Antypas, A. Banerjee, C. Bartram +123

The last decade has seen unprecedented effort in dark matter model building at all mass scales coupled with the design of numerous new detection strategies. Transformative advances…

hep-ph2022★ 4 cited

New Ideas in Baryogenesis: A Snowmass White Paper

Gilly Elor, Julia Harz, Seyda Ipek +21

The Standard Model of Particle Physics cannot explain the observed baryon asymmetry of the Universe. This observation is a clear sign of new physics beyond the Standard Model. Ther…

physics.ins-det2022★ 159 cited

A Next-Generation Liquid Xenon Observatory for Dark Matter and Neutrino Physics

J. Aalbers, K. Abe, V. Aerne +591

The nature of dark matter and properties of neutrinos are among the most pressing issues in contemporary particle physics. The dual-phase xenon time-projection chamber is the leadi…

hep-ex2022★ 24 cited

Axion Dark Matter

C. B. Adams, N. Aggarwal, A. Agrawal +152

Axions are well-motivated dark matter candidates with simple cosmological production mechanisms. They were originally introduced to solve the strong CP problem, but also arise in a…

hep-ph2022★ 12 cited

Early-Universe Model Building

Pouya Asadi, Saurabh Bansal, Asher Berlin +37

Theoretical investigations into the evolution of the early universe are an essential part of particle physics that allow us to identify viable extensions to the Standard Model as w…

hep-ph2022★ 9 cited

Cosmic Perturbations from a Rotating Field

Raymond T. Co, Keisuke Harigaya, Aaron Pierce

Complex scalar fields charged under approximate symmetries appear in well-motivated extensions of the Standard Model. One example is the field that contains the QCD axion fi…

hep-ph2021★ 2 cited

R-Parity Violation Axiogenesis

Raymond T. Co, Keisuke Harigaya, Zachary Johnson +1

We show that the rotation of the QCD axion field, aided by violation from supersymmetric -parity violating couplings, can yield the observed baryon abundance. Strong sphal…

hep-ph2021★ 90 cited

Gravitational Wave and CMB Probes of Axion Kination

Raymond T. Co, David Dunsky, Nicolas Fernandez +4

Rotations of an axion field in field space provide a natural origin for an era of kination domination, where the energy density is dominated by the kinetic term of the axion field,…

hep-ph2021★ 21 cited

The Race to Find Split Higgsino Dark Matter

Raymond T. Co, Benjamin Sheff, James D. Wells

Split higgsinos are a compelling class of models to explain dark matter and may be on the verge of detection by multiple current experimental avenues. The idea is based on a large…