All Outputs (20)

158 μm emission as an indicator of galaxy star formation rate (2023)
Journal Article
Liang, L., Feldmann, R., Murray, N., Narayanan, D., Hayward, C. C., Angles-Alcázar, D., …Hopkins, P. F. (2024). 158 μm emission as an indicator of galaxy star formation rate. Monthly notices of the Royal Astronomical Society, 528(1), 499-541. https://doi.org/10.1093/mnras/stad3792

Observations of local star-forming galaxies (SFGs) show a tight correlation between their singly ionized carbon line luminosity () and star formation rate (SFR), suggesting that may be a useful SFR tracer for galaxies. Some other galaxy populations,... Read More about 158 μm emission as an indicator of galaxy star formation rate.

Local positive feedback in the overall negative: the impact of quasar winds on star formation in the FIRE cosmological simulations (2023)
Journal Article
Mercedes-Feliz, J., Anglés-Alcázar, D., Hayward, C. C., Cochrane, R. K., Terrazas, B. A., Wellons, S., …Kereš, D. (2023). Local positive feedback in the overall negative: the impact of quasar winds on star formation in the FIRE cosmological simulations. Monthly notices of the Royal Astronomical Society, 524(3), 3446-3463. https://doi.org/10.1093/mnras/stad2079

Negative feedback from accreting supermassive black holes is considered crucial in suppressing star formation and quenching massive galaxies. However, several models and observations suggest that black hole feedback may have a positive effect, trigge... Read More about Local positive feedback in the overall negative: the impact of quasar winds on star formation in the FIRE cosmological simulations.

Hydrodynamic simulations of the disc of gas around supermassive black holes (HDGAS) -I. Molecular gas dynamics (2023)
Journal Article
Raouf, M., Viti, S., García-Burillo, S., Richings, A. J., Schaye, J., Bemis, A., …Holdship, J. (2023). Hydrodynamic simulations of the disc of gas around supermassive black holes (HDGAS) -I. Molecular gas dynamics. Monthly notices of the Royal Astronomical Society, 524(1), 786-800. https://doi.org/10.1093/mnras/stad1957

We present hydrodynamic simulations of the interstellar medium (ISM) within the circumnuclear disc (CND) of a typical active galactic nucleus (AGN)-dominated galaxy influenced by mechanical feedback from an AGN. The simulations are coupled with the C... Read More about Hydrodynamic simulations of the disc of gas around supermassive black holes (HDGAS) -I. Molecular gas dynamics.

Rapid disc settling and the transition from bursty to steady star formation in Milky Way-mass galaxies (2022)
Journal Article
Gurvich, A. B., Stern, J., Faucher-Giguère, C. A., Hopkins, P. F., Wetzel, A., Moreno, J., …Hafen, Z. (2023). Rapid disc settling and the transition from bursty to steady star formation in Milky Way-mass galaxies. Monthly notices of the Royal Astronomical Society, 519(2), 2598-2614. https://doi.org/10.1093/mnras/stac3712

Recent observations and simulations indicate substantial evolution in the properties of galaxies with time, wherein rotationally supported and steady thin discs (like those frequently observed in the local Universe) emerge from galaxies that are clum... Read More about Rapid disc settling and the transition from bursty to steady star formation in Milky Way-mass galaxies.

The effects of local stellar radiation and dust depletion on non-equilibrium interstellar chemistry (2022)
Journal Article
Richings, A. J., Faucher-Giguère, C. A., Gurvich, A. B., Schaye, J., & Hayward, C. C. (2022). The effects of local stellar radiation and dust depletion on non-equilibrium interstellar chemistry. Monthly notices of the Royal Astronomical Society, 517(2), 1557-1583. https://doi.org/10.1093/mnras/stac2338

Interstellar chemistry is important for galaxy formation, as it determines the rate at which gas can cool, and enables us to make predictions for observable spectroscopic lines from ions and molecules. We explore two central aspects of modelling the... Read More about The effects of local stellar radiation and dust depletion on non-equilibrium interstellar chemistry.

Unravelling the physics of multiphase AGN winds through emission line tracers (2021)
Journal Article
Richings, A. J., Faucher-Giguère, C. A., & Stern, J. (2021). Unravelling the physics of multiphase AGN winds through emission line tracers. Monthly notices of the Royal Astronomical Society, 503(2), 1568-1585. https://doi.org/10.1093/mnras/stab556

Observations of emission lines in active galactic nuclei (AGNs) often find fast (∼1000 km s−1) outflows extending to kiloparsec scales, seen in ionized, neutral atomic and molecular gas. In this work we present radiative transfer calculations of emis... Read More about Unravelling the physics of multiphase AGN winds through emission line tracers.

The changing circumgalactic medium over the last 10 Gyr-I. Physical and dynamical properties (2020)
Journal Article
Huscher, E., Oppenheimer, B. D., Lonardi, A., Crain, R. A., Richings, A. J., & Schaye, J. (2021). The changing circumgalactic medium over the last 10 Gyr-I. Physical and dynamical properties. Monthly notices of the Royal Astronomical Society, 500(1), 1476-1490. https://doi.org/10.1093/mnras/staa3203

We present an analysis of the physical and dynamical states of two sets of EAGLE zoom simulations of galaxy haloes, one at high redshift (z = 2-3) and the other at low redshift (z = 0), with masses of ≈10^12 M. Our focus is how the circumgalactic med... Read More about The changing circumgalactic medium over the last 10 Gyr-I. Physical and dynamical properties.

Reproducing the CO-to-H2 conversion factor in cosmological simulations of Milky-Way-mass galaxies (2020)
Journal Article
Keating, L. C., Richings, A. J., Murray, N., Faucher-Giguère, C. A., Hopkins, P. F., Wetzel, A., …Orr, M. E. (2020). Reproducing the CO-to-H2 conversion factor in cosmological simulations of Milky-Way-mass galaxies. Monthly notices of the Royal Astronomical Society, 499(1), 837-850. https://doi.org/10.1093/mnras/staa2839

We present models of CO(1-0) emission from Milky-Way-mass galaxies at redshift zero in the FIRE-2 cosmological zoom-in simulations. We calculate the molecular abundances by post-processing the simulations with an equilibrium chemistry solver while ac... Read More about Reproducing the CO-to-H2 conversion factor in cosmological simulations of Milky-Way-mass galaxies.

Pressure balance in the multiphase ISM of cosmologically simulated disc galaxies (2020)
Journal Article
Gurvich, A. B., Faucher-Giguère, C. A., Richings, A. J., Hopkins, P. F., Grudić, M. Y., Hafen, Z., …Murray, N. (2020). Pressure balance in the multiphase ISM of cosmologically simulated disc galaxies. Monthly notices of the Royal Astronomical Society, 498(3), 3664-3683. https://doi.org/10.1093/mnras/staa2578

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 understood. We address this question by using a set of FIRE-2 cosmologica... Read More about Pressure balance in the multiphase ISM of cosmologically simulated disc galaxies.

The multiphase circumgalactic medium traced by low metal ions in EAGLE zoom simulations (2018)
Journal Article
Oppenheimer, B. D., Schaye, J., Crain, R. A., Werk, J. K., & Richings, A. J. (2018). The multiphase circumgalactic medium traced by low metal ions in EAGLE zoom simulations. Monthly notices of the Royal Astronomical Society, 481(1), 835-859. https://doi.org/10.1093/mnras/sty2281

We explore the circumgalactic metal content traced by commonly observed low ion absorbers, including C II, SiII, SiIII, SiIV, and MgII. We use a set of cosmological hydrodynamical zoom simulations run with the EAGLE model and including a non-equilibr... Read More about The multiphase circumgalactic medium traced by low metal ions in EAGLE zoom simulations.

Radiative cooling of swept-up gas in AGN-driven galactic winds and its implications for molecular outflows (2018)
Journal Article
Richings, A. J., & Faucher-Giguère, C. A. (2018). Radiative cooling of swept-up gas in AGN-driven galactic winds and its implications for molecular outflows. Monthly notices of the Royal Astronomical Society, 478(3), 3100-3119. https://doi.org/10.1093/MNRAS/STY1285

We recently used hydrochemical simulations to demonstrate that molecular outflows observed in luminous quasars can be explained by molecule formation within the active galactic nucleus (AGN) wind. However, these simulations cover a limited parameter... Read More about Radiative cooling of swept-up gas in AGN-driven galactic winds and its implications for molecular outflows.

The origin of fast molecular outflows in quasars: Molecule formation in AGN-driven galactic winds (2017)
Journal Article
Richings, A. J., & Faucher-Giguère, C. A. (2018). The origin of fast molecular outflows in quasars: Molecule formation in AGN-driven galactic winds. Monthly notices of the Royal Astronomical Society, 474(3), 3673-3699. https://doi.org/10.1093/mnras/stx3014

We explore the origin of fast molecular outflows that have been observed in active galactic nuclei (AGNs). Previous numerical studies have shown that it is difficult to create such an outflow by accelerating existing molecular clouds in the host gala... Read More about The origin of fast molecular outflows in quasars: Molecule formation in AGN-driven galactic winds.

Flickering AGN can explain the strong circumgalactic OVI observed by COS-Halos (2017)
Journal Article
Oppenheimer, B. D., Segers, M., Schaye, J., Richings, A. J., & Crain, R. A. (2018). Flickering AGN can explain the strong circumgalactic OVI observed by COS-Halos. Monthly notices of the Royal Astronomical Society, 474(4), 4740-4755. https://doi.org/10.1093/mnras/stx2967

Proximity zone fossils (PZFs) are ionization signatures around recently active galactic nuclei (AGNs) where metal species in the circumgalactic medium remain overionized after the AGNs have shut offdue to their long recombination time scales. We expl... Read More about Flickering AGN can explain the strong circumgalactic OVI observed by COS-Halos.

Metals in the circumgalactic medium are out of ionization equilibrium due to fluctuating active galactic nuclei (2017)
Journal Article
Segers, M. C., Oppenheimer, B. D., Schaye, J., & Richings, A. J. (2017). Metals in the circumgalactic medium are out of ionization equilibrium due to fluctuating active galactic nuclei. Monthly notices of the Royal Astronomical Society, 471(1), 1026-1044. https://doi.org/10.1093/MNRAS/STX1633

We study the effect of a fluctuating active galactic nucleus (AGN) on the abundance of circumgalactic OVI in galaxies selected from the Evolution and Assembly of GaLaxies and their Environments simulations. We follow the time-variable OVI abundance i... Read More about Metals in the circumgalactic medium are out of ionization equilibrium due to fluctuating active galactic nuclei.

Chemical evolution of giant molecular clouds in simulations of galaxies (2016)
Journal Article
Richings, A. J., & Schaye, J. (2016). Chemical evolution of giant molecular clouds in simulations of galaxies. Monthly notices of the Royal Astronomical Society, 460(3), 2297-2321. https://doi.org/10.1093/mnras/stw1135

We present an analysis of giant molecular clouds (GMCs) within hydrodynamic simulations of isolated, low-mass (M* ~ 10^9 M⊙) disc galaxies. We study the evolution of molecular abundances and the implications for CO emission and the XCO conversion fac... Read More about Chemical evolution of giant molecular clouds in simulations of galaxies.

Bimodality of low-redshift circumgalactic O VI in non-equilibrium EAGLE zoom simulations (2016)
Journal Article
Oppenheimer, B. D., Crain, R. A., Schaye, J., Rahmati, A., Richings, A. J., Trayford, J. W., …Theuns, T. (2016). Bimodality of low-redshift circumgalactic O VI in non-equilibrium EAGLE zoom simulations. Monthly notices of the Royal Astronomical Society, 460(2), 2157-2179. https://doi.org/10.1093/mnras/stw1066

We introduce a series of 20 cosmological hydrodynamical simulations of L* (M200 = 10^11.7-10^12.3M⊙) and group-sized (M200 = 10^12.7-10^13.3M⊙) haloes run with the model used for the eagle project, which additionally includes a non-equilibrium ioniza... Read More about Bimodality of low-redshift circumgalactic O VI in non-equilibrium EAGLE zoom simulations.

The effects of metallicity, UV radiation and non-equilibrium chemistry in high-resolution simulations of galaxies (2016)
Journal Article
Richings, A. J., & Schaye, J. (2016). The effects of metallicity, UV radiation and non-equilibrium chemistry in high-resolution simulations of galaxies. Monthly notices of the Royal Astronomical Society, 458(1), 270-292. https://doi.org/10.1093/mnras/stw327

We present a series of hydrodynamic simulations of isolated galaxies with stellar mass of 109M˙. The models use a resolution of 750M˙ per particle and include a treatment for the full non-equilibrium chemical evolution of ions and molecules (157 spec... Read More about The effects of metallicity, UV radiation and non-equilibrium chemistry in high-resolution simulations of galaxies.

Non-equilibrium chemistry and cooling in the diffuse interstellar medium - II. Shielded gas (2014)
Journal Article
Richings, A. J., Schaye, J., & Oppenheimer, B. D. (2014). Non-equilibrium chemistry and cooling in the diffuse interstellar medium - II. Shielded gas. Monthly notices of the Royal Astronomical Society, 442(3), 2780-2796. https://doi.org/10.1093/mnras/stu1046

We extend the non-equilibrium model for the chemical and thermal evolution of diffuse interstellar gas presented in Richings et al. to account for shielding from the UV radiation field. We attenuate the photochemical rates by dust and by gas, includi... Read More about Non-equilibrium chemistry and cooling in the diffuse interstellar medium - II. Shielded gas.

Non-equilibrium chemistry and cooling in the diffuse interstellar medium - I. Optically thin regime (2014)
Journal Article
Richings, A. J., Schaye, J., & Oppenheimer, B. D. (2014). Non-equilibrium chemistry and cooling in the diffuse interstellar medium - I. Optically thin regime. Monthly notices of the Royal Astronomical Society, 440(4), 3349-3369. https://doi.org/10.1093/mnras/stu525

An accurate treatment of the multiphase interstellar medium (ISM) in hydrodynamic galaxy simulations requires that we follow not only the thermal evolution of the gas, but also the evolution of its chemical state, including its molecular chemistry, w... Read More about Non-equilibrium chemistry and cooling in the diffuse interstellar medium - I. Optically thin regime.

The connection between radio loudness and central surface brightness profiles in optically selected low-luminosity active galaxies (2011)
Journal Article
Richings, A. J., Uttley, P., & Körding, E. (2011). The connection between radio loudness and central surface brightness profiles in optically selected low-luminosity active galaxies. Monthly notices of the Royal Astronomical Society, 415(3), 2158-2172. https://doi.org/10.1111/j.1365-2966.2011.18845.x

Recent results indicate a correlation between nuclear radio loudness of active galaxies and their central stellar surface-brightness profiles, in that 'core' galaxies (with inner logarithmic slope γ≤ 0.3) are significantly more radio loud than 'power... Read More about The connection between radio loudness and central surface brightness profiles in optically selected low-luminosity active galaxies.