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Dr Djuna Lize Croon's Outputs (13)

Cosmic microwave background constraints on extended dark matter objects (2024)
Journal Article
Croon, D., & Muñoz, S. S. (2024). Cosmic microwave background constraints on extended dark matter objects. Journal of Cosmology and Astroparticle Physics, 2024(07), Article 060. https://doi.org/10.1088/1475-7516/2024/07/060

Primordially formed extended dark objects would accrete baryonic matter and impact the ionisation history of the Universe. Insisting on consistency with the anisotropies of the cosmic microwave background, we derive constraints on the dark matter fra... Read More about Cosmic microwave background constraints on extended dark matter objects.

Microlensing signatures of extended dark objects using machine learning (2024)
Journal Article
Crispim Romao, M., & Croon, D. (2024). Microlensing signatures of extended dark objects using machine learning. Physical Review D, 109(12), Article 123004. https://doi.org/10.1103/physrevd.109.123004

This paper presents a machine learning-based method for the detection of the unique gravitational microlensing signatures of extended dark objects, such as boson stars, axion miniclusters and subhalos. We adapt MicroLIA, a machine learning-based pack... Read More about Microlensing signatures of extended dark objects using machine learning.

TASI lectures on Phase Transitions, Baryogenesis, and Gravitational Waves (2024)
Presentation / Conference Contribution
Croon, D. (2022, June). TASI lectures on Phase Transitions, Baryogenesis, and Gravitational Waves. Presented at 2022 Theoretical Advanced Study Institute in Particle Theory, University of Colorado, Boulder

These lectures, presented at the 2022 TASI summer school, give an introductory overview of first-order phase transitions in the early Universe, baryogenesis, and the resulting gravitational wave phenomenology. We introduce thermal field theory via th... Read More about TASI lectures on Phase Transitions, Baryogenesis, and Gravitational Waves.

Light axion emission and the formation of merging binary black holes (2023)
Journal Article
Croon, D., & Sakstein, J. (2023). Light axion emission and the formation of merging binary black holes. Physical Review D, 108, Article 015034. https://doi.org/10.1103/PhysRevD.108.015034

We study the impact of stellar cooling due to light axion emission on the formation and evolution of black hole binaries, via stable mass transfer and the common envelope scenario. We find that in
the presence of light axion emission, no binary blac... Read More about Light axion emission and the formation of merging binary black holes.

Gravitational wave constraints on extended dark matter structures (2023)
Journal Article
Croon, D., Ipek, S., & McKeen, D. (2023). Gravitational wave constraints on extended dark matter structures. Physical Review D, 107(6), Article 063012. https://doi.org/10.1103/physrevd.107.063012

We generalize existing constraints on primordial black holes to dark objects with extended sizes using the aLIGO design sensitivity. We show that LIGO is sensitive to dark objects with radius Oð10 − 103 kmÞ if they make up more than ∼Oð10−2 − 10−3Þ o... Read More about Gravitational wave constraints on extended dark matter structures.

Tidal Love numbers of novel and admixed celestial objects (2022)
Journal Article
Collier, M., Croon, D., & Leane, R. K. (2022). Tidal Love numbers of novel and admixed celestial objects. Physical Review D, 106(12), Article 123027. https://doi.org/10.1103/physrevd.106.123027

A subfraction of dark matter or new particles trapped inside celestial objects can significantly alter their macroscopic properties. We investigate the new physics imprint on celestial objects by using a generic framework to solve the Tolman-Oppenhei... Read More about Tidal Love numbers of novel and admixed celestial objects.

Leptogenesis enabled by dark matter (2022)
Journal Article
Croon, D., Davoudiasl, H., & Houtz, R. (2022). Leptogenesis enabled by dark matter. Physical Review D, 106(3), https://doi.org/10.1103/physrevd.106.035006

We propose that weak scale leptogenesis via ∼10TeV scale right-handed neutrinos could be possible if their couplings had transitory larger values in the early Universe. The requisite lifted parameters can be attained if a light scalar ϕ is displaced... Read More about Leptogenesis enabled by dark matter.

Snowmass2021 theory frontier white paper: Astrophysical and cosmological probes of dark matter (2022)
Journal Article
Boddy, K. K., Lisanti, M., McDermott, S. D., Rodd, N. L., Weniger, C., Ali-Haïmoud, Y., …Witte, S. J. (2022). Snowmass2021 theory frontier white paper: Astrophysical and cosmological probes of dark matter. Journal of High Energy Astrophysics, 35, https://doi.org/10.1016/j.jheap.2022.06.005

While astrophysical and cosmological probes provide a remarkably precise and consistent picture of the quantity and general properties of dark matter, its fundamental nature remains one of the most significant open questions in physics. Obtaining a m... Read More about Snowmass2021 theory frontier white paper: Astrophysical and cosmological probes of dark matter.

Axion instability supernovae (2022)
Journal Article
Sakstein, J., Croon, D., & McDermott, S. D. (2022). Axion instability supernovae. Physical Review D, 105(9), Article 095038. https://doi.org/10.1103/physrevd.105.095038

and strongly coupled. In this work, we investigate the astrophysical consequences of such a scenario for massive stars by incorporating new contributions to the equation of state into a state of the art stellar structure code. We focus on axions in t... Read More about Axion instability supernovae.

Machine learning a manifold (2022)
Journal Article
Craven, S., Croon, D., Cutting, D., & Houtz, R. (2022). Machine learning a manifold. Physical Review D, 105(9), Article 096030. https://doi.org/10.1103/physrevd.105.096030

We propose a simple method to identify a continuous Lie algebra symmetry in a dataset through regression by an artificial neural network. Our proposal takes advantage of the Oðϵ2Þ scaling of the output variable under infinitesimal symmetry transforma... Read More about Machine learning a manifold.

Light dark matter through resonance scanning (2022)
Journal Article
Croon, D., Elor, G., Houtz, R., Murayama, H., & White, G. (2022). Light dark matter through resonance scanning. Physical Review D, 105(6), https://doi.org/10.1103/physrevd.105.l061303

We propose a new out-of-equilibrium production mechanism of light dark matter: resonance scanning. If the dark matter mass evolved in the early Universe, resonant production may have occurred for a wide range of light dark matter masses today. We sho... Read More about Light dark matter through resonance scanning.

Find the Gap: Black Hole Population Analysis with an Astrophysically Motivated Mass Function (2021)
Journal Article
Baxter, E. J., Croon, D., McDermott, S. D., & Sakstein, J. (2021). Find the Gap: Black Hole Population Analysis with an Astrophysically Motivated Mass Function. Astrophysical Journal Letters, 916(2), Article L16. https://doi.org/10.3847/2041-8213/ac11fc

We introduce a novel black hole mass function that realistically models the physics of pair-instability supernovae with a minimal number of parameters. Applying this to all events in the LIGO-Virgo Gravitational-Wave Transient Catalog 2 (GWTC-2), we... Read More about Find the Gap: Black Hole Population Analysis with an Astrophysically Motivated Mass Function.