Article
Astronomy & Astrophysics
Enrico M. Di Teodoro, Lorenzo Posti, Patrick M. Ogle, S. Michael Fall, Thomas Jarrett
Summary: We studied the kinematics and scaling relations of 43 giant spiral galaxies and found that most of them conform to the standards set by low-mass galaxies. It is speculated that these rare giant galaxies are scaled up versions of smaller discs, indicating that spiral galaxies exhibit self-similarity at the high-mass end.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Rahul Ramesh, Dylan Nelson, Annalisa Pillepich
Summary: We analysed the physical properties of gas in the circumgalactic medium (CGM) of 132 Milky Way-like galaxies at z=0 and found diverse properties and abundance of CGM gas across the sample, with considerable variations in the fractional budgets of different phases and in neutral H I mass and metal mass. The CGM exhibits great structural complexity, both within individual galaxies and across different galaxies. The physical properties of the CGM are tightly connected to the galactic star formation rate, which is dependent on feedback from supermassive black holes (SMBHs).
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Michael S. Petersen, Martin D. Weinberg, Neal Katz
Summary: By using a new algorithm to measure orbit volume, we can rapidly identify resonant orbits, leading to a better understanding of evolving galaxy models.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Michael S. Petersen, Martin D. Weinberg, Neal Katz
Summary: This article presents the N-body simulation techniques implemented in the exp code, which uses empirically chosen basis functions to expand the potential field of a ensemble of particles. The research finds that the method can accurately expand highly non-spherical objects and achieves comparable or even better accuracy than direct-summation or tree-based calculations, while being computationally less intensive.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Soumavo Ghosh, Kanak Saha, Chanda J. Jog, Francoise Combes, Paola di Mateo
Summary: This study investigates the occurrence of m = 1 lopsidedness in disc galaxies during minor mergers. It shows that a minor merger triggers a prominent m = 1 lopsidedness in stars of the host galaxy, but this lopsidedness disappears rapidly after the merger. A delayed merger can lead to a prolonged m = 1 lopsidedness, which rotates in a pattern different from the m = 2 bar pattern. Furthermore, the merger causes an off-centred stellar disc-dark matter halo configuration in the host galaxy.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
J. Read, G. A. Mamon, E. Vasiliev, L. L. Watkins, M. G. Walker, J. Penarrubia, M. Wilkinson, W. Dehnen, P. Das
Summary: In this study, four different mass modelling methods were applied to mock data for spherical stellar systems, showing good recovery of density and velocity anisotropy for isotropic and tangentially anisotropic data, but facing challenges with radially anisotropic data. Only methods incorporating shape information of the velocity distribution function were able to break the degeneracy between the density profile and the velocity anisotropy for line-of-sight data, while including proper motion data led to further improvements in recovering both radial density and velocity anisotropy profiles.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Yong Shi, Xiaoling Yu, Shude Mao, Qiusheng Gu, Xiaoyang Xia, Yanmei Chen
Summary: This study demonstrates a universal correlation between stellar masses of galaxies and the product of dynamical velocities and sizes at the effective radii, with little evolution over cosmic time. The observed scatter in this correlation allows for a potential distance estimator with an uncertainty independent of galaxy type. The underlying physical mechanisms behind this correlation remain unclear, although a toy model of self-regulation between binding energies and supernovae feedback shows promise in reproducing the observed slopes.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Anqi Li, Antonino Marasco, Filippo Fraternali, Scott Trager, Marc A. W. Verheijen
Summary: A kinematic study of ionized extraplanar gas in two low-inclination late-type galaxies reveals the presence of ionized gas with specific scale heights and flux fractions, as well as lagging rotation and weak evidence of radial inflow. The results suggest similarities with the kinematics of neutral gas, but further research with a dynamical model is needed to better understand the formation of ionized extraplanar gas.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Matthew Frosst, Stephane Courteau, Nikhil Arora, Connor Stone, Andrea Maccio, Marvin Blank
Summary: An analysis of observed and simulated galaxy data reveals diversity in galaxy structural parameters, rotation curve shapes, and stellar mass profiles. Two distinct populations are identified, one consisting of low-mass blue spirals with constant rotation curve slopes, and the other consisting of redder, more massive, and more diverse spirals with increasing slopes. The study also shows that the diversity increases mildly with mass.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Nabeel Rehemtulla, Monica Valluri, Eugene Vasiliev
Summary: Spherical Jeans modelling is commonly used for estimating mass profiles of various systems, ranging from star clusters to galactic stellar haloes and clusters of galaxies, by deriving cumulative mass distributions.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
S. de Beer, S. Cantalupo, A. Travascio, G. Pezzulli, M. Galbiati, M. Fossati, M. Fumagalli, T. Lazeyras, A. Pensabene, T. Theuns, W. Wang
Summary: Lyα nebulae around quasars at high redshift can provide unique constraints on the properties of the circumgalactic medium. A new method based on velocity dispersion maps of Lyα emission is presented to constrain the quasar halo masses. The results show that Lyα radiative transfer effects do not change the shape of the velocity dispersion profiles, but only their normalization. This method can be directly applied to observations to estimate the halo mass of quasars.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Simon Weng, Celine Peroux, Arjun Karki, Ramona Augustin, Varsha P. Kulkarni, Aleksandra Hamanowicz, Martin Zwaan, Elaine M. Sadler, Dylan Nelson, Matthew J. Hayes, Glenn G. Kacprzak, Andrew J. Fox, Victoria Bollo, Benedetta Casavecchia, Roland Szakacs
Summary: The study investigates the gas flow into and out of galaxies using absorption lines towards background quasars. By analyzing 27 H I absorbers, the researchers examine the flow of neutral gas in the circumgalactic medium and compare it with the properties of associated galaxies. The results suggest that the baryon cycle has a significant impact on star formation and galaxy evolution.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Aaron D. Ludlow, S. Michael Fall, Matthew J. Wilkinson, Joop Schaye, Danail Obreschkow
Summary: This study uses cosmological simulations to investigate the impact of spurious heating of stellar motions within simulated galaxies by dark matter particles. The results show that spurious heating affects the distribution and kinematics of stellar and DM particles, but has little effect on galaxy properties such as mass and star formation histories.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Aditya Manuwal, Aaron D. Ludlow, Adam R. H. Stevens, Ruby J. Wright, Aaron S. G. Robotham
Summary: We studied the asymmetry of H I emission-line profiles of galaxies in the EAGLE simulation using three different measures. We found that galaxies with symmetric H I line profiles are typically rotationally supported, while those with asymmetric line profiles may or may not be dispersion-dominated. Galaxies with symmetric H I emission lines are more gas rich and show differences in their star formation rates. The asymmetry of the line profiles is strongly correlated with the dynamical state of a galaxy's dark matter halo, and at fixed halo mass, asymmetric centrals tend to have more massive subhaloes and experience higher rates of gas accretion and outflow.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Sharon Lapiner, Avishai Dekel, Yohan Dubois
Summary: Through cosmological simulation, this study explores the relationship between galaxy evolution and central black hole growth. It finds that supernova feedback plays a key role in slowing down black hole growth in smaller dark matter halos, while the heating of circumgalactic medium allows rapid growth in larger halos. The onset of black hole growth is triggered by wet-compaction events, causing major transitions in galaxy properties and potentially leading to star-formation quenching.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Spencer C. Wallace, Thomas R. Quinn, Aaron C. Boley
Summary: The text discusses the importance of second-generation dust produced by collisions of planetesimals in circumstellar discs for exploring the physical conditions of the disc. It also highlights how perturbing planets can create non-axisymmetric structures and gaps in the dust, regardless of their origin.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Angelo Ricarte, Michael Tremmel, Priyamvada Natarajan, Charlotte Zimmer, Thomas Quinn
Summary: The research characterizes the population of wandering black holes in the ROMULUS cosmological simulations, finding that their number scales roughly linearly with halo mass. Thousands of wandering black holes are expected in galaxy cluster haloes, accounting for around 10% of the local black hole mass budget. At higher redshifts, wandering black holes outweigh and outshine their central supermassive counterparts.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Urmila Chadayammuri, Michael Tremmel, Daisuke Nagai, Arif Babul, Thomas Quinn
Summary: The study demonstrates that AGN feedback and mergers have significant impacts on the intracluster medium, with AGN feedback gently controlling star formation in the brightest cluster galaxy and mergers disrupting the structure of the cluster, cutting off the supply of low-entropy gas.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Tomas Tamfal, Lucio Mayer, Thomas R. Quinn, Pedro R. Capelo, Stelios Kazantzidis, Arif Babul, Douglas Potter
Summary: The text discusses the orbital decay of a perturber within a larger system and the attempts to determine the underlying physics and timescales of the drag mechanism using different approaches. Through ultra-high-resolution N-body simulations, both local and global perturbations' effects were captured and the torque's origin was analyzed.
ASTROPHYSICAL JOURNAL
(2021)
Article
Astronomy & Astrophysics
Santi Roca-Fabrega, Ji-hoon Kim, Loic Hausammann, Kentaro Nagamine, Alessandro Lupi, Johnny W. Powell, Ikkoh Shimizu, Daniel Ceverino, Joel R. Primack, Thomas R. Quinn, Yves Revaz, Hector Velazquez, Tom Abel, Michael Buehlmann, Avishai Dekel, Bili Dong, Oliver Hahn, Cameron Hummels, Ki-won Kim, Britton D. Smith, Clayton Strawn, Romain Teyssier, Matthew J. Turk
Summary: A suite of high-resolution cosmological zoom-in simulations to z = 4 of a 10(12) M (circle dot) halo at z = 0 were presented, using seven contemporary astrophysical simulation codes. The simulations included cosmological processes such as the expansion of the universe, intergalactic gas inflow, and the cosmic ultraviolet background radiation. The careful comparison of galaxy formation simulations by different code groups showed overall agreement in gas and stellar properties but differences in circumgalactic medium properties.
ASTROPHYSICAL JOURNAL
(2021)
Article
Astronomy & Astrophysics
Angelo Ricarte, Michael Tremmel, Priyamvada Natarajan, Thomas Quinn
Summary: While most galaxies may have a central supermassive black hole (SMBH), there could also be a substantial population of off-center wandering SMBHs naturally produced during galaxy assembly. Recent Romulus cosmological simulations predict various electromagnetic signatures for these wanderers, with some potentially originating from SMBHs within satellite galaxies. The simulations also suggest a significant population of secondary active galactic nuclei (AGNs), necessitating a correction to current theoretically estimated tidal disruption event (TDE) rates at low SMBH masses.
ASTROPHYSICAL JOURNAL LETTERS
(2021)
Article
Astronomy & Astrophysics
Jillian M. Bellovary, Sarra Hayoune, Katheryn Chafla, Donovan Vincent, Alyson Brooks, Charlotte R. Christensen, Ferah D. Munshi, Michael Tremmel, Thomas R. Quinn, Jordan Van Nest, Serena K. Sligh, Michelle Luzuriaga
Summary: Studies suggest that massive black holes in dwarf galaxies may not be located at the center of their hosts, but rather off-center. This is primarily due to galaxy-galaxy mergers, and off-center black holes are unlikely to quickly sink to the center of galaxies.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Robert Wissing, Sijing Shen, James Wadsley, Thomas Quinn
Summary: The magnetorotational instability (MRI) is an important process in driving turbulence in sufficiently ionized accretion disks. In this study, we successfully simulated MRI turbulence using the smoothed particle hydrodynamics (SPH) method and obtained consistent results with prior work using grid-based codes, demonstrating the effectiveness of SPH in studying MRI.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
Jordan D. Van Nest, F. Munshi, A. C. Wright, M. Tremmel, A. M. Brooks, D. Nagai, T. Quinn
Summary: This study explores the characteristics of populations of ultra-diffuse galaxies (UDGs) in isolated, satellite, and cluster environments using simulations. The results show that isolated UDGs have distinct features compared to non-UDG counterparts, indicating a more disk-like structure. The choice of UDG definition and viewing orientation can significantly affect the classification of dwarf populations as UDGs. Furthermore, the classification of a galaxy as a UDG is influenced by environmental density. Therefore, the definition of UDG populations needs to be considered for understanding the formation and evolution of UDGs.
ASTROPHYSICAL JOURNAL
(2022)
Article
Astronomy & Astrophysics
Tomas Tamfal, Lucio Mayer, Thomas R. Quinn, Arif Babul, Piero Madau, Pedro R. Capelo, Sijing Shen, Marius Staub
Summary: In this study, a cosmological N-body hydrodynamical simulation with unprecedented resolution was used to investigate the formation process of a Milky Way-sized galaxy halo. The simulated galaxy exhibits early assembly characteristics consistent with extrapolations of star-forming galaxy main sequences to higher redshifts. The results suggest the early presence of a compact, thin rotating stellar disk and a multi-component structure, challenging previous literature reports of upside-down disk growth, with implications for high-redshift galaxy observations.
ASTROPHYSICAL JOURNAL
(2022)
Article
Astronomy & Astrophysics
S. Lyla Jung, Douglas Rennehan, Vida Saeedzadeh, Arif Babul, Michael Tremmel, Thomas R. Quinn, S. Ilani Loubser, E. O'Sullivan, Sukyoung K. Yi
Summary: Contrary to stereotypes, observed brightest group galaxies (BGGs) exhibit diversity in their properties. Using the Romulus simulations, this study finds that Romulus reproduces the diversity of BGGs well, albeit with a tendency towards a lower fraction of quenched BGGs compared to observations. The study also reveals the existence of both early-type and late-type galaxies, as well as galaxies transitioning from late-type to early-type due to strong dynamical interactions with satellites.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Ray S. Sharma, Alyson M. Brooks, Michael Tremmel, Jillian Bellovary, Angelo Ricarte, Thomas R. Quinn
Summary: This study explores the characteristics of actively accreting massive black holes within dwarf galaxies using the Romulus25 cosmological hydrodynamic simulation. The study focuses on the MBH occupation fraction, X-ray active fractions, and active galactic nucleus (AGN) scaling relations. The findings indicate changes in the MBH occupation fraction and overall number density of dwarf AGN since z = 2, and predict the existence of a large population of low-luminosity hidden MBHs in the local universe.
ASTROPHYSICAL JOURNAL
(2022)
Article
Astronomy & Astrophysics
Iryna S. Butsky, Jessica K. Werk, Kirill Tchernyshyov, Drummond B. Fielding, Joseph Breneman, Daniel R. Piacitelli, Thomas R. Quinn, N. Nicole Sanchez, Akaxia Cruz, Cameron B. Hummels, Joseph N. Burchett, Michael Tremmel
Summary: We use hydrodynamical simulations to show that cosmic-ray pressure has a significant impact on the kinematics of cool and warm circumgalactic gas. The presence of cosmic-ray pressure creates a cooler circumgalactic medium and leads to narrower O vi absorption features and broader Si iii absorption features, which are more consistent with observational data. Direct comparisons between simulations and observations can reveal the dominant physical mechanisms that shape the circumgalactic medium.
ASTROPHYSICAL JOURNAL
(2022)
Article
Astronomy & Astrophysics
A. Cruz, A. Pontzen, M. Volonteri, T. R. Quinn, M. Tremmel, A. M. Brooks, N. N. Sanchez, F. Munshi, A. Di Cintio
Summary: Using cosmological hydrodynamic simulations, this study compares the formation and growth of Milky Way-mass galaxies in cold dark matter (CDM) and self-interacting dark matter (SIDM) models. The results show that interactions in SIDM suppress early SMBH formation and mergers, leading to delayed growth and different evolution compared to CDM.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Elaad Applebaum, Alyson M. Brooks, Charlotte R. Christensen, Ferah Munshi, Thomas R. Quinn, Sijing Shen, Michael Tremmel
Summary: This study presents results from high-resolution cosmological simulations on the Mint resolution DC Justice League suite, showing detailed research on ultrafaint dwarf galaxies. The simulations predict that the majority of nearby galaxies will be observable and provide insights into the formation mechanisms of faint dwarf galaxies.
ASTROPHYSICAL JOURNAL
(2021)