papers

Publications (19)

astro-ph.GA2025

Rising from the Ashes II: The Bar-driven Abundance Bimodality of the Milky Way

Angus Beane, James Johnson, Vadim Semenov +3

The Milky Way hosts at least two modes in its present day distribution of Fe and alpha-elements. The exact cause of this bimodality is disputed, but one class of explanations invol…

astro-ph.GA2025

Mapping the Milky Way in 5-D with 170 Million Stars

Joshua S. Speagle, Catherine Zucker, Ana Bonaca +18

We present "augustus", a catalog of distance, extinction, and stellar parameter estimates to 170 million stars from and with dr…

astro-ph.GA2022

Characterizing the 3D Kinematics of Young Stars in the Radcliffe Wave

Alan J. Tu, Catherine Zucker, Joshua S. Speagle +5

We present an analysis of the kinematics of the Radcliffe Wave, a 2.7-kpc-long sinusoidal band of molecular clouds in the solar neighborhood recently detected via 3D dust mapping.…

astro-ph.GA2025

The Impact of Classical Bulges on Stellar Bars and Box-Peanut-X-Features in Disk Galaxies

Rachel Lee McClure, Angus Beane, Elena D'Onghia +2

Galactic bars and their associated resonances play a significant role in shaping galaxy evolution. Resulting resonance-driven structures, like the vertically extended Boxy/Peanut X…

astro-ph.GA2025

Rising from the Ashes: A Metallicity-Dependent Star Formation Gap Splits the Milky Way's alpha-Sequences

Angus Beane

The elemental abundance distribution of stars encodes the history of the gas-phase abundance in the Milky Way. Without a large, unbiased sample of highly precise stellar ages, the…

astro-ph.CO2019

Tomography of the Cosmic Dawn and Reionization Eras with Multiple Tracers

Tzu-Ching Chang, Angus Beane, Olivier Dore +41

The Cosmic Dawn and Reionization epochs remain a fundamental but challenging frontier of astrophysics and cosmology. We advocate a large-scale, multi-tracer approach to develop a c…

astro-ph.SR2025

Deriving Stellar Properties, Distances, and Reddenings using Photometry and Astrometry with BRUTUS

Joshua S. Speagle, Catherine Zucker, Angus Beane +18

We present brutus, an open source Python package for quickly deriving stellar properties, distances, and reddenings to stars based on grids of stellar models constrained by photome…

astro-ph.SR2019

In the Galactic disk, stellar [Fe/H] and age predict orbits and precise [X/Fe]

Melissa K. Ness, Kathryn V. Johnston, Kirsten Blancato +4

We explore the structure of the element abundance--age--orbit distribution of the stars in the Milky Way's low- disk, by (re-)deriving precise [Fe/H], [X/Fe] and ages, along wi…

astro-ph.GA2025

Secular Attrition of Classical Bulges by Stellar Bars

Rachel Lee McClure, Tobias Géron, Elena D'Onghia +5

Classical bulges and stellar bars are common features in disk galaxies and serve as key tracers of galactic evolution. Angular momentum exchange at bar resonances drives secular mo…

astro-ph.GA2023

How Nested Bars Enhance, Modulate, and are Destroyed by Gas Inflows

Zhi Li, Min Du, Victor P. Debattista +7

Gas flows in the presence of two independently-rotating nested bars remain not fully understood, which is likely to play an important role in fueling the central black hole. We use…

astro-ph.SR2020

Exploring the evolution of stellar rotation using Galactic kinematics

Ruth Angus, Angus Beane, Adrian M. Price-Whelan +9

The rotational evolution of cool dwarfs is poorly constrained after around 1-2 Gyr due to a lack of precise ages and rotation periods for old main-sequence stars. In this work we u…

astro-ph.CO2019

Measuring the EoR Power Spectrum Without Measuring the EoR Power Spectrum

Angus Beane, Francisco Villaescusa-Navarro, Adam Lidz

The large-scale structure of the Universe should soon be measured at high redshift during the Epoch of Reionization (EoR) through line-intensity mapping. A number of ongoing and pl…

astro-ph.SR2018

Actions are weak stellar age indicators in the Milky Way disk

Angus Beane, Melissa K. Ness, Megan Bedell

The orbital properties of stars in the disk are signatures of their formation, but they are also expected to change over time due to the dynamical evolution of the Galaxy. Stellar…

astro-ph.CO2021

Fuzzy Dark Matter and the 21cm Power Spectrum

Dana Jones, Skyler Palatnick, Richard Chen +2

We model the 21cm power spectrum across the Cosmic Dawn and the Epoch of Reionization (EoR) in fuzzy dark matter (FDM) cosmologies. The suppression of small mass halos in FDM model…

astro-ph.CO2018

Extracting bias using the cross-bispectrum: An EoR and 21 cm-[CII]-[CII] case study

Angus Beane, Adam Lidz

The amplitude of redshifted 21 cm fluctuations during the Epoch of Reionization (EoR) is expected to show a distinctive "rise and fall" behavior with decreasing redshift as reioniz…

astro-ph.GA2019

The Implications of Local Fluctuations in the Galactic Midplane for Dynamical Analysis in the Gaia Era

Angus Beane, Robyn E. Sanderson, Melissa K. Ness +6

Orbital properties of stars, computed from their six-dimensional phase space measurements and an assumed Galactic potential, are used to understand the structure and evolution of t…

astro-ph.GA2023

Stellar Bars in Isolated Gas-Rich Spiral Galaxies Do Not Slow Down

Angus Beane, Lars Hernquist, Elena D'Onghia +6

Elongated bar-like features are ubiquitous in galaxies, occurring at the centers of approximately two-thirds of spiral disks in the nearby Universe. Due to gravitational interactio…

astro-ph.CO2025

Ray-tracing Fast Radio Bursts Through IllustrisTNG: Cosmological Dispersion Measures from Redshift 0 to 5.5

Ralf M. Konietzka, Liam Connor, Vadim A. Semenov +3

The dispersion measures (DMs) of Fast Radio Bursts (FRBs) arise predominantly from free electrons in the large-scale structure of the Universe. The increasing number of FRB observa…

astro-ph.CO2024

Insights into the 21 cm field from the vanishing cross-power spectrum at the epoch of reionization

Kana Moriwaki, Angus Beane, Adam Lidz

The early stages of the Epoch of Reionization, probed by the 21 cm line, are sensitive to the detailed properties and formation histories of the first galaxies. We use 21cmFAST and…