Article
Astronomy & Astrophysics
Nils Wittenburg, Pavel Kroupa, Indranil Banik, Graeme Candlish, Nick Samaras
Summary: We perform the first hydrodynamical cosmological simulations in the nu HDM framework based on Milgromian dynamics (MOND) with light (11 eV) sterile neutrinos. The simulations show that nu HDM can explain various cosmological phenomena while preserving MOND's successes on galaxy scales. We also investigate the growth of structure and discuss the tension between the onset of group/cluster-scale structure formation and observations of high redshift galaxies.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Review
Astronomy & Astrophysics
Claude-Andre Faucher-Giguere, S. Peng Oh
Summary: The past decade has witnessed significant theoretical progress in our understanding of the circumgalactic medium (CGM) due to rich observations and advanced simulations. The properties of the CGM are determined by the competition between gravity-driven infall and gas cooling. The interaction between the hot and cold phases of the multiphase gas and the effect of CGM on galaxy evolution remain open questions.
ANNUAL REVIEW OF ASTRONOMY AND ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
Tiago Costa, Fabrizio Arrigoni Battaia, Emanuele P. Farina, Laura C. Keating, Joakim Rosdahl, Taysun Kimm
Summary: The detection of Ly alpha nebulae around z>6 quasars reveals extended gas reservoirs around rapidly growing supermassive black holes. Cosmological models can explain the observations of z>6 quasars, but it is uncertain whether they can also explain the observed extended Ly alpha emission. The study finds that a combination of recombination radiation and emission from collisionally excited gas can power Ly alpha nebulae in agreement with observations.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Zachary Hafen, Jonathan Stern, James Bullock, Alexander B. Gurvich, Sijie Yu, Claude-Andre Faucher-Giguere, Drummond B. Fielding, Daniel Angles-Alcazar, Eliot Quataert, Andrew Wetzel, Tjitske Starkenburg, Michael Boylan-Kolchin, Jorge Moreno, Robert Feldmann, Kareem El-Badry, T. K. Chan, Cameron Trapp, Dusan Keres, Philip F. Hopkins
Summary: The study suggests that a key factor in the formation of thin stellar discs in Milky Way-mass galaxies is the aligned angular momentum distribution of accreting gas before joining the galaxy; galaxies with a thick disc or irregular morphology lack gas angular momentum alignment. Simulation results indicate a strong correlation between rotating cooling flow accretion mode and thin disc galaxies.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Chris Byrohl, Dylan Nelson
Summary: We develop a comprehensive theoretical model for Lyman-alpha (Lyα) emission, from the scale of individual Lyα emitters (LAEs) to Lyα haloes (LAHs), Lyα blobs (LABs), and Lyα filaments (LAFs) of the diffuse cosmic web itself. By post-processing a cosmological magnetohydrodynamical simulation, we capture the resonant scattering process of Lyα photons and build an emission model incorporating recombinations and collisions in diffuse gas, radiative effects from nearby AGN, and emission sourced by stellar populations. Our model provides insights into the observability and physical origin of the Lyα cosmic web, revealing that diffuse Lyα filaments are illuminated by photons from the intergalactic medium, galaxies, and their gaseous haloes. We predict the abundance, area, linear size, and embedded halo/emitter populations within filaments and suggest that the Lyα cosmic web can be detected with modern integral field spectrographs.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
N. J. F. Gillet, D. Aubert, F. G. Mertens, P. Ocvirk
Summary: The study introduces a simulation framework for cosmic dawn and reionization that can track dark matter, hydrodynamics, and radiative transfer on large scales, while also dealing with galaxy formation scale to produce a simulated 21 cm signal as close as possible to observations.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Richard Wuensch, Stefanie Walch, Frantisek Dinnbier, Daniel Seifried, Sebastian Haid, Andre Klepitko, Anthony P. Whitworth, Jan Palous
Summary: The TREERAY method is a solution for handling multiple radiation sources in radiative transfer problems, with computational cost independent of the number of sources, making it versatile for various simulations.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Nicholas P. Herrington, Clare L. Dobbs, Thomas J. R. Bending
Summary: We present hydrodynamic and magnetohydrodynamic simulations of sub-galactic regions, including photoionizing and supernova feedback. By including an initial population of stars, we improve the initial conditions of our region extraction models. We find that the main role of a prior population is triggering star formation and contributing to gas dynamics.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Benjamin Kimock, Desika Narayanan, Aaron Smith, Xiangcheng Ma, Robert Feldmann, Daniel Angles-Alcazar, Volker Bromm, Romeel Dave, James E. Geach, Philip Hopkins, Dusan Keres
Summary: High-redshift Ly alpha blobs (LABs) are a mysterious class of objects studied through observational and theoretical investigations. The dominant power sources for their luminosity include recombination in star-forming galaxies and cooling emission from accretion, with fluorescence caused by active galactic nuclei also contributing significantly. The emergent Ly alpha luminosity from a system is a complex function of the gas temperature, ionization state, and Ly alpha escape fraction.
ASTROPHYSICAL JOURNAL
(2021)
Article
Astronomy & Astrophysics
Cesar Hernandez-Aguayo, Christian Arnold, Baojiu Li, Carlton M. Baugh
Summary: In this study, 'full-physics' hydrodynamical simulations of galaxy formation in the nDGP braneworld model were conducted to investigate the impact of baryonic physics on galactic scales and make predictions on the stellar content of dark matter haloes and galaxy evolution. Significant differences between general relativity and nDGP models were found in the power spectra and correlation functions of gas, stars, and dark matter, with baryonic effects influencing the overall matter distribution clustering. The study also revealed that the effects of modified gravity and galactic feedback on matter clustering can be distinctly separated, allowing for accurate prediction of the matter power spectrum with baryonic effects included.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Jie Li, Danail Obreschkow, Chris Power, Claudia del P. Lagos
Summary: In the early universe, it was often assumed that diffuse gas and cold dark matter (DM) were mixed well enough to experience identical tidal torques. However, cosmological simulations consistently show that DM haloes end up with higher specific angular momentum (sAM) in gas, even without radiative cooling and galaxy formation physics. Our analysis of spin distributions in well-resolved haloes reveals that on average, the sAM of halo gas is about 40% higher than that of DM. This difference can be attributed to an excess AM in the inner halo, along with a more coherent rotation pattern in the gas. We find that the leading driver for this difference is the collapse of pressurized inner gas shells, which causes the DM ellipsoid to spin ahead of the gas ellipsoid, transferring AM from DM to gas. A simple model combining initial spin, axes ratios, and collapse factor can predict the AM transfer in ellipsoidal collapse and explain the average excess AM of gas in non-radiative cosmological simulations.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Hidenobu Yajima, Makito Abe, Sadegh Khochfar, Kentaro Nagamine, Akio K. Inoue, Tadayuki Kodama, Shohei Arata, Claudio Dalla Vecchia, Hajime Fukushima, Takuya Hashimoto, Nobunari Kashikawa, Mariko Kubo, Yuexing Li, Yuichi Matsuda, Ken Mawatari, Masami Ouchi, Hideki Umehata
Summary: This study presents results from a new cosmological hydrodynamics simulation campaign of protocluster regions, showing the formation and evolution of galaxies in extremely overdense regions. The simulations reveal the presence of starburst galaxies and supermassive black holes in these regions, suggesting that protoclusters may kickstart cosmic reionization.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Fabio Di Mascia, Stefano Carniani, Simona Gallerani, Fabio Vito, Andrea Pallottini, Andrea Ferrara, Milena Valentini
Summary: A study finds that when the radiation from AGN is included in simulations, the SFR of host galaxies is overestimated by approximately ten times, suggesting that AGN plays an effective role in heating dust in the host galaxy.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Daniele Sorini, John A. Peacock
Summary: The revised and extended analytical model for cosmic star formation, with modifications to make it more general, successfully reproduces observed features and history of star formation in the universe. The simplified apparatus not only has pedagogical value but also serves as a means for rapid exploration of non-standard cosmological models.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Martin Glatzle, Luca Graziani, Benedetta Ciardi
Summary: The presence of charged dust grains has a significant impact on the physical evolution of the interstellar medium, but this process is still poorly explored in numerical simulations. A novel implementation of grain charging in a radiative transfer code is introduced in this study, and its effects on grain properties and charge distribution are evaluated. The findings open up possibilities for further studies on the physical evolution of the dusty ISM accessible through observations of galaxies at different redshifts.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Gen Chiaki, Hajime Susa, Shingo Hirano
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2018)
Article
Astronomy & Astrophysics
Koki Higuchi, Masahiro N. Machida, Hajime Susa
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2018)
Article
Astronomy & Astrophysics
Koki Higuchi, Masahiro N. Machida, Hajime Susa
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2019)
Article
Astronomy & Astrophysics
Daisuke Nakauchi, Kazuyuki Omukai, Hajime Susa
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2019)
Article
Astronomy & Astrophysics
Daisuke Nakauchi, Kazuyuki Omukai, Hajime Susa
Summary: Magnetic fields play crucial roles in star formation, controlling the efficiency of circumstellar discs and multiple stellar systems. The temperature evolution and ionization degree of a cloud were recalculated for different metallicities, with new considerations including grain-surface chemistry.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Ataru Tanikawa, Hajime Susa, Takashi Yoshida, Alessandro A. Trani, Tomoya Kinugawa
Summary: The study presents the merger rate density of Population III binary black holes, revealing that mergers with high-mass black holes may dominate in the future. The effective spins of these mergers are low and the number ratio of different types of mergers varies.
ASTROPHYSICAL JOURNAL
(2021)
Article
Astronomy & Astrophysics
Sho Higashi, Hajime Susa, Gen Chiaki
Summary: The study reveals that turbulence in the primordial gas can be amplified through gravitational contraction in minihalos, even surpassing the sound speed despite small initial turbulent Mach numbers. An analytic formula for calculating the amplification of turbulent velocity in collapsing clouds is proposed and numerical results are found to be consistent with the formula. These findings indicate the importance of turbulence in collapsing clouds in general cases.
ASTROPHYSICAL JOURNAL
(2021)
Article
Astronomy & Astrophysics
Ataru Tanikawa, Takashi Yoshida, Tomoya Kinugawa, Alessandro A. Trani, Takashi Hosokawa, Hajime Susa, Kazuyuki Omukai
Summary: We investigate the formation of merging binary black holes through isolated binary evolution and find that the predicted merger rate density and primary black hole mass distribution are consistent with gravitational wave observations. Population III and EMP binary stars play a significant role in pair instability mass gap events, with the number of events increasing with redshift.
ASTROPHYSICAL JOURNAL
(2022)
Article
Astronomy & Astrophysics
Sho Higashi, Hajime Susa, Gen Chiaki
Summary: This study investigates the physical mechanism that determines the saturation level of turbulence in collapsing gas clouds. Through numerical simulations and an analytical expression, the relationship between the saturation level of turbulence and the effective polytropic exponent gamma(eff) is determined.
ASTROPHYSICAL JOURNAL
(2022)
Article
Astronomy & Astrophysics
Hajime Susa
ASTROPHYSICAL JOURNAL
(2019)
Proceedings Paper
Astronomy & Astrophysics
Shuta J. Tanaka, Gen Chiaki, Nozomu Tominaga, Hajime Susa
14TH INTERNATIONAL SYMPOSIUM ON ORIGIN OF MATTER AND EVOLUTION OF GALAXIES (OMEG 2017)
(2018)
Article
Astronomy & Astrophysics
Shuta J. Tanaka, Gen Chiaki, Nozomu Tominaga, Hajime Susa
ASTROPHYSICAL JOURNAL
(2017)
Article
Astronomy & Astrophysics
Tomoaki Ishiyama, Kae Sudo, Shingo Yokoi, Kenji Hasegawa, Nozomu Tominaga, Hajime Susa
ASTROPHYSICAL JOURNAL
(2016)
Article
Astronomy & Astrophysics
Hajime Susa, Kentaro Doi, Kazuyuki Omukai
ASTROPHYSICAL JOURNAL
(2015)
Article
Astronomy & Astrophysics
Y. Tsukamoto, M. N. Machida, H. Susa, H. Nomura, S. Inutsuka
ASTROPHYSICAL JOURNAL
(2020)