papers

Publications (71)

astro-ph.GA2022

FIRE-3: Updated Stellar Evolution Models, Yields, & Microphysics and Fitting Functions for Applications in Galaxy Simulations

Philip F. Hopkins, Andrew Wetzel, Coral Wheeler +18

Increasingly, uncertainties in predictions from galaxy formation simulations (at sub-Milky Way masses) are dominated by uncertainties in stellar evolution inputs. In this paper, we…

astro-ph.GA2019

Ultraviolet Perspectives on Diffuse Gas in the Largest Cosmic Structures

Joseph N. Burchett, Daisuke Nagai, Iryna Butsky +31

The past decade has seen an explosion of discoveries and new insights into the diffuse gas within galaxies, galaxy clusters, and the filaments composing the Cosmic Web. A new decad…

gr-qc1999

GRLite and GRTensorJ: Graphical user interfaces to the computer algebra system GRTensorII

Mustapha Ishak, Peter Musgrave, John Mourra +2

GRLite and GRTensorJ are first and second generation graphical user interfaces to the computer algebra system GRTensorII. Current development centers on GRTensorJ, which provides f…

astro-ph.GA2020

Virial shocks are suppressed in cosmic ray-dominated galaxy halos

Suoqing Ji, Dušan Kereš, T. K. Chan +5

We study the impact of cosmic rays (CRs) on the structure of virial shocks, using a large suite of high-resolution cosmological FIRE-2 simulations accounting for CR injection by su…

astro-ph.GA2025

Disks no more: the morphology of low-mass simulated galaxies in FIREbox

José A. Benavides, Laura V. Sales, Andrew Wetzel +9

We study the morphology of hundreds of simulated central galaxies in the stellar mass range \msun\, from the FIREbox cosmological volume. We demons…

astro-ph.HE2014

Radiation Pressure Confinement -- III. The origin of the broad ionization distribution in AGN outflows

Jonathan Stern, Ehud Behar, Ari Laor +2

The winds of ionized gas driven by Active Galactic Nuclei (AGN) can be studied through absorption lines in their X-ray spectra. A recurring feature of these outflows is their broad…

astro-ph.GA2020

Properties of the Circumgalactic Medium in Cosmic Ray-Dominated Galaxy Halos

Suoqing Ji, T. K. Chan, Cameron B. Hummels +6

We investigate the impact of cosmic rays (CRs) on the circumgalactic medium (CGM) in FIRE-2 simulations, for ultra-faint dwarf through Milky Way (MW)-mass halos hosting star-formin…

astro-ph.GA2024

X-ray signatures of galactic outflows into the circumgalactic medium

Ranita Jana, Kartick C. Sarkar, Jonathan Stern +1

We present a set of controlled hydrodynamical simulations to study the effects of strong galactic outflows on the density and temperature structures, and associated X-ray signature…

astro-ph.CO2012

Type 1 AGN at low z

Jonathan Stern, Ari Laor

We present the emission properties of a sample of 3,579 type 1 AGN, selected based on the detection of broad H-alpha emission. The sample covers the range of black hole mass 10^6<M…

astro-ph.GA2025

Turbulence-dominated CGM: the origin of UV absorbers with equivalent widths of Ã

Aharon Kakoly, Jonathan Stern, Claude-André Faucher-Giguère +4

Theoretical arguments and observations suggest that in massive halos (), the circumgalactic medium (CGM) is dominated by a 'hot' phase with gas temperature near…

astro-ph.GA2017

Small-scale Intensity Mapping: Extended Halos as a Probe of the Ionizing Escape Fraction and Faint Galaxy Populations during Reionization

Lluís Mas-Ribas, Joseph F. Hennawi, Mark Dijkstra +3

We present a new method to quantify the value of the escape fraction of ionizing photons, and the existence of ultra-faint galaxies clustered around brighter objects during the epo…

astro-ph.IM2023

Line Emission Mapper (LEM): Probing the physics of cosmic ecosystems

Ralph Kraft, Maxim Markevitch, Caroline Kilbourne +107

The Line Emission Mapper (LEM) is an X-ray Probe for the 2030s that will answer the outstanding questions of the Universe's structure formation. It will also provide transformative…

astro-ph.GA2019

Cooling flow solutions for the circumgalactic medium

Jonathan Stern, Drummond Fielding, Claude-André Faucher-Giguère +1

In several models of galaxy formation feedback occurs in cycles or mainly at high redshift. At times and in regions where feedback heating is ineffective, hot gas in the galaxy hal…

astro-ph.CO2013

Radiation Pressure Confinement - I. Ionized Gas in the ISM of AGN Hosts

Jonathan Stern, Ari Laor, Alexei Baskin

We analyze the hydrostatic effect of AGN radiation pressure on optically thick gas in the host galaxy. We show that in luminous AGN, the radiation pressure likely confines the ioni…

astro-ph.GA2026

Galaxy Metallicity Gradients in the Reionization Epoch from the FIRE-2 Simulations

Xunda Sun, Xin Wang, Fangzhou Jiang +10

We employ the high-redshift suite of FIRE-2 cosmological hydrodynamic zoom-in simulations to investigate the evolution of gas-phase metallicity radial gradients in galaxies in the…

astro-ph.GA2025

Molecular Hydrogen in High-redshift Damped Lyman-α Absorbers

Alon Gurman, Amiel Sternberg, Shmuel Bialy +2

Simulations predict that circumgalactic hydrogen gas surrounding massive () galaxies at may be predominantly neutral, and c…

astro-ph.GA2026

Under Pressure: UV Emission Line Ratios as Barometers of AGN Feedback Mechanisms

Elise Fuller, Sean D. Johnson, Jonathan Stern +16

Feedback from active galactic nuclei (AGN) is widely acknowledged to regulate the growth of massive galaxies, though its driving mechanisms are debated. Prevailing theories suggest…

astro-ph.GA2015

Spatially Resolving the Kinematics of the <100 μas Quasar Broad Line Region using Spectroastrometry

Jonathan Stern, Joseph F. Hennawi, Jörg-Uwe Pott

The broad line region (BLR) of luminous active galactic nuclei (AGN) is a prominent observational signature of the accretion flow around supermassive black holes, which can be used…

astro-ph.GA2022

A Transient "Changing-look'' Active Galactic Nucleus Resolved on Month Timescales from First-year Sloan Digital Sky Survey V Data

Grisha Zeltyn, Benny Trakhtenbrot, Michael Eracleous +32

We report the discovery of a new ``changing-look'' active galactic nucleus (CLAGN) event, in the quasar SDSS J162829.17+432948.5 at z=0.2603, identified through repeat spectroscopy…

astro-ph.GA2025

The physical origin of positive metallicity radial gradients in high-redshift galaxies: insights from the FIRE-2 cosmological hydrodynamic simulations

Xunda Sun, Xin Wang, Xiangcheng Ma +11

Using the FIRE-2 cosmological zoom-in simulations, we investigate the temporal evolution of gas-phase metallicity radial gradients of Milky Way-mass progenitors in the redshift ran…

astro-ph.GA2025

Project AMIGA: The Inner Circumgalactic Medium of Andromeda from Thick Disk to Halo

Nicolas Lehner, J. Christopher Howk, Lucy Collins +22

The inner circumgalactic medium (CGM) of galaxies, where disk and halo processes intersect, remains poorly characterized despite its critical role in regulating galaxy evolution. W…

astro-ph.GA2026

Enhanced Multiphase Circumgalactic Medium and Gas Cycling in Galaxy Mergers

Maolan Yang, Suoqing Ji, Robert Feldmann +9

We investigate the impact of galaxy mergers on the circumgalactic medium (CGM) using the FIREbox cosmological hydrodynamic simulation. By comparing matched samples of merging and i…

astro-ph.GA2026

Cold vs. Hot Gas Accretion and Angular Momentum in FIRE Simulations: From Halo to Galaxy Scales

Imran Sultan, Claude-André Faucher-Giguère, Jonathan Stern +1

We present a systematic study of gas accretion and angular momentum in the circumgalactic medium (CGM) using high-resolution FIRE cosmological simulations. Our analysis includes ha…

astro-ph.GA2022

Rapid disc settling and the transition from bursty to steady star formation in Milky Way-mass galaxies

Alexander B. Gurvich, Jonathan Stern, Claude-André Faucher-Giguère +6

Recent observations and simulations indicate substantial evolution in the properties of galaxies with time, wherein rotationally-supported and steady thin discs (like those frequen…

astro-ph.GA2016

A Universal Density Structure for Circum-Galactic Gas

Jonathan Stern, Joseph F. Hennawi, J. Xavier Prochaska +1

We develop a new method to constrain the physical conditions in the cool (~10^4 K) circumgalactic medium (CGM) from measurements of ionic column densities, by assuming that the coo…

astro-ph.GA2021

Neutral CGM as damped Lyα absorbers at high redshift

Jonathan Stern, Amiel Sternberg, Claude-André Faucher-Giguère +8

Recent searches for the hosts of high-redshift () damped Ly absorbers (DLAs) have detected bright galaxies at distances of tens of kpc from the DLA. Using the FIRE-2…

astro-ph.GA2021

OVI Traces Photoionized Streams With Collisionally Ionized Boundaries in Cosmological Simulations of Massive Galaxies

Clayton Strawn, Santi Roca-FÃ brega, Nir Mandelker +6

We analyse the distribution and origin of OVI in the Circumgalactic Medium (CGM) of dark-matter haloes of M at in the VELA cosmological zoom-in simu…

astro-ph.CO2013

Type 1 AGN at low z. III. The optical narrow line ratios

Jonathan Stern, Ari Laor

We present the optical narrow line ratios in an SDSS based sample of 3,175 broad Ha selected type 1 AGN, and explore their positions in the BPT diagrams as a function of the AGN an…

astro-ph.GA2026

Hot accretion onto spiral galaxies: the origin of extended and warped HI discs

Sriram Sankar, Jonathan Stern, Chris Power +6

Gas accretion, hot ( K) atmospheres, and a tilt between the rotation axes of the disc and the atmosphere are all common predictions of standard galaxy evolution theory f…

astro-ph.GA2019

Understanding the circumgalactic medium is critical for understanding galaxy evolution

Molly S. Peeples, Peter Behroozi, Rongmon Bordoloi +69

Galaxies evolve under the influence of gas flows between their interstellar medium and their surrounding gaseous halos known as the circumgalactic medium (CGM). The CGM is a major…

astro-ph.GA2021

Thermal Instability in the CGM of Galaxies: Testing "Precipitation" Models with the FIRE Simulations

Clarke J. Esmerian, Andrey V. Kravtsov, Zachary Hafen +5

We examine the thermodynamic state and cooling of the low- Circum-Galactic Medium (CGM) in five FIRE-2 galaxy formation simulations of Milky Way-mass galaxies. We find that the…

astro-ph.HE2019

Evidence for Radiation Pressure Compression in the X-ray Narrow Line Region of Seyfert galaxies

Stefano Bianchi, Matteo Guainazzi, Ari Laor +2

The observed spatial and kinematic overlap between soft X-ray emission and the Narrow Line Region (NLR) in obscured Active Galactic Nuclei (AGN) yields compelling evidence that rel…

astro-ph.GA2025

A Turbulent Framework for Star Formation in High-Redshift Galaxies

Guochao Sun, Claude-André Faucher-Giguère, Jonathan Stern

Observations of distant galaxies suggest that the physics of galaxy formation at high redshifts differs significantly from later times. In contrast to large, steady disk galaxies l…

astro-ph.GA2025

Second public data release of the FIRE-2 cosmological zoom-in simulations of galaxy formation

Andrew Wetzel, Jenna Samuel, Pratik J. Gandhi +34

We describe the second data release (DR2) of the FIRE-2 cosmological zoom-in simulations of galaxy formation, from the Feedback In Realistic Environments (FIRE) project, available…

astro-ph.GA2021

The bursty origin of the Milky Way thick disc

Sijie Yu, James S. Bullock, Courtney Klein +11

We investigate thin and thick stellar disc formation in Milky-Way-mass galaxies using twelve FIRE-2 cosmological zoom-in simulations. All simulated galaxies experience an early per…

astro-ph.GA2021

Which AGN Jets Quench Star Formation in Massive Galaxies?

Kung-Yi Su, Philip F. Hopkins, Greg L. Bryan +12

Without additional heating, radiative cooling of gas in the halos of massive galaxies (Milky Way and above) produces cold gas or stars in excess of that observed. Previous work sug…

astro-ph.GA2026

Resolving galaxy formation in the early Universe with BonFIRE and CampFIRE

Jenna Samuel, Michael Boylan-Kolchin, Robert Feldmann +16

The abundance and rapid growth of galaxies at cosmic dawn revealed by the James Webb Space Telescope challenges models of galaxy formation, motivating new simulations to uncover th…

astro-ph.GA2023

Born this way: thin disc, thick disc, and isotropic spheroid formation in FIRE-2 Milky-Way-mass galaxy simulations

Sijie Yu, James S. Bullock, Alexander B. Gurvich +7

We investigate the formation of Milky-Way-mass galaxies using FIRE-2 LCDM cosmological zoom-in simulations by studying the orbital evolution of stars formed in the main progenitor…

astro-ph.GA2020

The time-scales probed by star formation rate indicators for realistic, bursty star formation histories from the FIRE simulations

José A. Flores Velázquez, Alexander B. Gurvich, Claude-André Faucher-Giguère +10

Understanding the rate at which stars form is central to studies of galaxy formation. Observationally, the star formation rates (SFRs) of galaxies are measured using the luminosity…

astro-ph.GA2024

Comparison of Models for the Warm-Hot Circumgalactic Medium around Milky Way-like Galaxies

Priyanka Singh, Erwin T. Lau, Yakov Faerman +2

A systematic comparison of the models of the circumgalactic medium (CGM) and their observables is crucial to understanding the predictive power of the models and constraining physi…

astro-ph.GA2026

MUSEQuBES: Physical conditions, origins, and multi-element abundances of the circumgalactic medium of an isolated, star-forming dwarf galaxy at z=0.57

Sean D. Johnson, Nishant Mishra, Sowgat Muzahid +13

In dwarf galaxy models, outflows expel metal-enriched interstellar medium (ISM) into the circumgalactic medium (CGM) to reproduce their observed low metallicities, but measurements…

astro-ph.GA2026

From protogalaxy through thick and thin: Why did the Milky Way evolve in three kinematic phases?

Olti Myrtaj, James S. Bullock, Michael Boylan-Kolchin +8

APOGEE and Gaia data have revealed that the Milky Way's structure appears to have evolved through three distinct kinematic phases. First, at early cosmic times, the Milky Way was a…

astro-ph.GA2024

Arkenstone I: A Novel Method for Robustly Capturing High Specific Energy Outflows In Cosmological Simulations

Matthew C. Smith, Drummond B. Fielding, Greg L. Bryan +11

Arkenstone is a new model for multiphase, stellar feedback driven galactic winds designed for inclusion in coarse resolution cosmological simulations. In this first paper of a seri…

astro-ph.GA2023

What Causes The Formation of Disks and End of Bursty Star Formation?

Philip F. Hopkins, Alexander B. Gurvich, Xuejian Shen +17

As they grow, galaxies can transition from irregular/spheroidal with 'bursty' star formation histories (SFHs), to disky with smooth SFHs. But even in simulations, the direct physic…

astro-ph.GA2023

The imprint of bursty star formation on alpha-element abundance patterns in Milky Way-like galaxies

Hanna Parul, Jeremy Bailin, Andrew Wetzel +5

Milky Way-mass galaxies in the FIRE-2 simulations demonstrate two main modes of star formation. At high redshifts star formation occurs in a series of short and intense bursts, whi…

astro-ph.GA2021

Unravelling the physics of multiphase AGN winds through emission line tracers

Alexander J. Richings, Claude-Andre Faucher-Giguere, Jonathan Stern

Observations of emission lines in Active Galactic Nuclei (AGN) often find fast (~1000 km s^-1) outflows extending to kiloparsec scales, seen in ionised, neutral atomic and molecula…

astro-ph.GA2026

The Shape of FIREbox Galaxies and a Potential Tension with Low-mass Disks

Courtney Klein, Jenny D. Wang, Luke Xia +9

We study the intrinsic and observable shapes of approximately 700 star-forming galaxies with stellar masses of M from the FIREbox simulation at . We c…

astro-ph.GA2020

Spatially-resolved UV diagnostics of AGN feedback: radiation pressure dominates in a prototypical quasar-driven superwind

Jean Somalwar, Sean D. Johnson, Jonathan Stern +5

Galactic-scale winds driven by active galactic nuclei (AGN) are often invoked to suppress star formation in galaxy evolution models, but the mechanisms driving these outflows are h…

astro-ph.CO2013

Radiation pressure confinement - II. Application to the broad line region in active galactic nuclei

Alexei Baskin, Ari Laor, Jonathan Stern

Active galactic nuclei (AGN) are characterized by similar broad emission lines properties at all luminosities (- erg s). What produces this similarity over…

astro-ph.GA2020

Probing the CGM of Low-redshift Dwarf Galaxies Using FIRE Simulations

Fei Li, Mubdi Rahman, Norman Murray +7

Observations of UV metal absorption lines have provided insight into the structure and composition of the circumgalactic medium (CGM) around galaxies. We compare these observations…

astro-ph.GA2020

The maximum accretion rate of hot gas in dark matter halos

Jonathan Stern, Drummond Fielding, Claude-André Faucher-Giguère +1

We revisit the question of 'hot mode' versus 'cold mode' accretion onto galaxies using steady-state cooling flow solutions and idealized 3D hydrodynamic simulations. We demonstrate…

astro-ph.GA2024

Accretion onto disk galaxies via hot and rotating CGM inflows

Jonathan Stern, Drummond Fielding, Zachary Hafen +5

Observed accretion rates onto the Milky-Way and other local spirals fall short of that required to sustain star formation for cosmological timescales. A potential avenue for this u…

astro-ph.GA2020

Pressure balance in the multiphase ISM of cosmologically simulated disk galaxies

Alexander B. Gurvich, Claude-André Faucher-Giguère, Alexander J. Richings +13

Pressure balance plays a central role in models of the interstellar medium (ISM), but whether and how pressure balance is realized in a realistic multiphase ISM is not yet well und…

astro-ph.GA2016

Evidence that most type 1 AGN are reddened by dust in the host ISM

Dalya Baron, Jonathan Stern, Dovi Poznanski +1

The typical optical-UV continuum slopes observed in many type 1 AGN are redder than expected from thin accretion disk models. A possible resolution to this conundrum is that many A…

astro-ph.GA2026

Accretion-Driven Turbulence in the Circumgalactic Medium

Roy Goldner, Jonathan Stern, Drummond Fielding +3

Simulations suggest that turbulence is ubiquitous in the circumgalactic medium (CGM), though the source and properties of CGM turbulence is uncertain. Using analytic considerations…

astro-ph.GA2024

Ne VIII in the warm-hot circumgalactic medium of FIRE simulations and in observations

Nastasha A. Wijers, Claude-André Faucher-Giguère, Jonathan Stern +2

The properties of warm-hot gas around galaxies can be studied with absorption lines from highly ionized metals. We predict Ne VIII column densities from cosmological z…

astro-ph.GA2023

A unified model for the co-evolution of galaxies and their circumgalactic medium: the relative roles of turbulence and atomic cooling physics

Viraj Pandya, Drummond B. Fielding, Greg L. Bryan +7

The circumgalactic medium (CGM) plays a pivotal role in regulating gas flows around galaxies and thus shapes their evolution. However, the details of how galaxies and their CGM co-…

astro-ph.GA2025

Cooling Flows as a Reference Solution for the Hot Circumgalactic Medium

Imran Sultan, Claude-André Faucher-Giguère, Jonathan Stern +3

The circumgalactic medium (CGM) in halos is dominated by a hot phase ( K). While many models exist for the hot gas structur…

astro-ph.GA2020

Virialization of the inner CGM in the FIRE simulations and implications for galaxy discs, star formation and feedback

Jonathan Stern, Claude-André Faucher-Giguère, Drummond Fielding +13

We use the FIRE-2 cosmological simulations to study the formation of a quasi-static, virial-temperature gas phase in the circumgalactic medium (CGM) at redshifts 0<z<5, and how the…

astro-ph.GA2022

Stellar feedback-regulated black hole growth: driving factors from nuclear to halo scales

Lindsey Byrne, Claude-André Faucher-Giguère, Jonathan Stern +4

Several recent simulations of galaxy formation predict two main phases of supermassive black hole (BH) accretion: an early, highly intermittent phase (during which BHs are under-ma…

astro-ph.GA2021

Characterizing mass, momentum, energy and metal outflow rates of multi-phase galactic winds in the FIRE-2 cosmological simulations

Viraj Pandya, Drummond B. Fielding, Daniel Anglés-Alcázar +14

We characterize mass, momentum, energy and metal outflow rates of multi-phase galactic winds in a suite of FIRE-2 cosmological "zoom-in" simulations from the Feedback in Realistic…

astro-ph.GA2018

Does circumgalactic OVI trace low-pressure gas beyond the accretion shock? Clues from HI and low-ion absorption, line kinematics, and dust extinction

Jonathan Stern, Claude-André Faucher-Giguère, Joseph F. Hennawi +3

Large OVI columns are observed around star-forming, low-redshift ~L* galaxies, with a dependence on impact parameter indicating that most O^5+ particles reside beyond half the halo…

astro-ph.GA2023

The Halo21 Absorption Modeling Challenge: Lessons From "Observing" Synthetic Circumgalactic Absorption Spectra

Zachary Hafen, Sameer, Cameron Hummels +7

In the Halo21 absorption modeling challenge we generated synthetic absorption spectra of the circumgalactic medium (CGM), and attempted to estimate the metallicity, temperature, an…

astro-ph.GA2025

Kinematics of Circumgalactic O VI Gas and Disk Rotation of Star-forming Galaxies

Stephanie H. Ho, Crystal L. Martin, Hasti Nateghi +2

Quasar sightline observations reveal that low-ionization-state gas corotates with the galaxy disk and often at sub-centrifugal velocities, suggesting that the gas is spiraling towa…

astro-ph.CO2012

Type 1 low z AGN. I. Emission properties

Jonathan Stern, Ari Laor

We analyze the emission properties of a new sample of 3,579 type 1 AGN, selected from the SDSS DR7 based on the detection of broad H-alpha emission. The sample extends over a broad…

astro-ph.GA2022

Hot-mode accretion and the physics of thin-disk galaxy formation

Zachary Hafen, Jonathan Stern, James Bullock +16

We use FIRE simulations to study disk formation in z~0, Milky Way-mass galaxies, and conclude that a key ingredient for the formation of thin stellar disks is the ability for accre…

astro-ph.GA2021

Spatially Resolving the Kinematics of the as Quasar Broad-line Region Using Spectroastrometry II. The First Tentative Detection in a Luminous Quasar at

Felix Bosco, Joseph F. Hennawi, Jonathan Stern +1

Direct measurements of the masses of supermassive black holes (SMBHs) are key to understanding their growth and constrain their symbiotic relationship to their host galaxies. Howev…

astro-ph.GA2025

Where is the Super-Virial Gas? The Supply from hot inflows

Manami Roy, Kung-Yi Su, Smita Mathur +1

In an effort to understand the presence of super-virial gas detected in the Milky Way, we present our findings from isolated galaxy simulations of Milky Way-like systems using GIZM…

astro-ph.GA2016

Constraining the dynamical importance of hot gas and radiation pressure in quasar outflows using emission line ratios

Jonathan Stern, Claude-Andre Faucher-Giguere, Nadia L. Zakamska +1

Quasar feedback models often predict an expanding hot gas bubble which drives a galaxy-scale outflow. In many circumstances this hot gas radiates inefficiently and is therefore dif…

astro-ph.GA2014

Radiation pressure confinement - IV. Application to broad absorption line outflows

Alexei Baskin, Ari Laor, Jonathan Stern

A fraction of quasars present broad absorption lines, produced by outflowing gas with typical velocities of 3000 - 10,000 km/s. If the outflowing gas fills a significant fraction o…

astro-ph.CO2012

Type 1 AGN at low z. II. The relative strength of narrow lines and the nature of intermediate type AGN

Jonathan Stern, Ari Laor

We explore the relative strength of the narrow emission lines in an SDSS based sample of broad H-alpha selected AGN, defined in paper I. We find a decrease in the narrow to broad H…