130 citations · 412 across the 24 of their papers we have counts for
24 papers
ERGO-ML: A continuous organization of the X-ray galaxy cluster population in TNG-Cluster with contrastive learning
Urmila Chadayammuri, Lukas Eisert, Annalisa Pillepich +3
The physical properties of the intracluster medium (ICM) reflect signatures of the underlying gravitational potential, mergers and strong interactions with other halos and satellit…
What is the Role of Large Language Models in the Evolution of Astronomy Research?
Morgan Fouesneau, Ivelina G. Momcheva, Urmila Chadayammuri +10
ChatGPT and other state-of-the-art large language models (LLMs) are rapidly transforming multiple fields, offering powerful tools for a wide range of applications. These models, co…
Closing Pandora's Box -- The deepest X-ray observations of Abell 2744 and a multi-wavelength merger picture
Urmila Chadayammuri, Ákos Bogdán, Gerrit Schellenberger +1
Abell 2744, also known as Pandora's Cluster, is a complex merging galaxy cluster. While a major merger is clear along the north-south axis, the dynamical state of the northwest sub…
X-Ray Bright Active Galactic Nuclei in Local Dwarf Galaxies: Insights from eROSITA
Andrea Sacchi, Akos Bogdan, Urmila Chadayammuri +1
Although supermassive black holes (SMBHs) reside in the heart of virtually every massive galaxy, it remains debated whether dwarf galaxies commonly host SMBHs. Because low-mass gal…
Improved Constraints on Mergers with SZ, Hydrodynamical simulations, Optical, and X-ray (ICM-SHOX). Paper II: Galaxy cluster sample overview
Emily M. Silich, Elena Bellomi, Jack Sayers +12
Galaxy cluster mergers are representative of a wide range of physics, making them an excellent probe of the properties of dark matter and the ionized plasma of the intracluster med…
A candidate supermassive black hole in a gravitationally-lensed galaxy at
Orsolya E. Kovacs, Akos Bogdan, Priyamvada Natarajan +8
While supermassive black holes (BHs) are widely observed in the nearby and distant universe, their origin remains debated with two viable formation scenarios with light and heavy s…
Decoding the Early Universe: Exploring a Merger Scenario for the High-Redshift Cluster JKCS041 using Numerical Models
Sharon Felix, Antareep Gogoi, Kaitlyn Shavelle +6
JKCS041 () is one of the most distant galaxy cluster systems known, seen when the Universe was less than 4 billion years old. Recent Sunyaev-Zeldovich (SZ) observations show…
Constraints on thermal conductivity in the merging cluster Abell 2146
A. Richard-Laferrière, H. R. Russell, A. C. Fabian +9
The cluster of galaxies Abell 2146 is undergoing a major merger and is an ideal cluster to study ICM physics, as it has a simple geometry with the merger axis in the plane of the s…
ICM-SHOX. Paper I: Methodology overview and discovery of a gas--dark matter velocity decoupling in the MACS J0018.5+1626 merger
Emily M. Silich, Elena Bellomi, Jack Sayers +12
Galaxy cluster mergers are rich sources of information to test cluster astrophysics and cosmology. However, cluster mergers produce complex projected signals that are difficult to…
Painting baryons onto N-body simulations of galaxy clusters with image-to-image deep learning
Urmila Chadayammuri, Michelle Ntampaka, John ZuHone +2
Galaxy cluster mass functions are a function of cosmology, but mass is not a direct observable, and systematic errors abound in all its observable proxies. Mass-free inference can…
Evidence for heavy seed origin of early supermassive black holes from a z~10 X-ray quasar
Akos Bogdan, Andy Goulding, Priyamvada Natarajan +9
Observations of quasars reveal that many supermassive black holes (BHs) were in place less than 700 million years after the Big Bang. However, the origin of the first BHs remains a…
Tidal Disruption Event Demographics with the Zwicky Transient Facility: Volumetric Rates, Luminosity Function, and Implications for the Local Black Hole Mass Function
Yuhan Yao, Vikram Ravi, Suvi Gezari +26
We conduct a systematic tidal disruption event (TDE) demographics analysis using the largest sample of optically selected TDEs. A flux-limited, spectroscopically complete sample of…
Constraints from dwarf galaxies on black hole seeding and growth models with current and future surveys
Urmila Chadayammuri, Akos Bogdan, Angelo Ricarte +1
Dwarf galaxies are promising test beds for constraining models of supermassive and intermediate-mass black holes (MBH) via their black hole occupation fraction (BHOF). Disentanglin…
Weak-lensing mass bias in merging galaxy clusters
Wonki Lee, Sangjun Cha, M. James Jee +6
Although weak lensing (WL) is a powerful method to estimate a galaxy cluster mass without any dynamical assumptions, a model bias can arise when the cluster density profile departs…
The structure of cluster merger shocks: turbulent width and the electron heating timescale
H. R. Russell, P. E. J. Nulsen, D. Caprioli +10
We present a new 2 Ms Chandra observation of the cluster merger Abell 2146, which hosts two huge M~2 shock fronts each ~500 kpc across. For the first time, we resolve and measure t…
The X-ray Angular Power Spectrum of Extended Sources in the eROSITA Final Equatorial Depth Survey
Erwin T. Lau, Akos Bogdan, Urmila Chadayammuri +3
The eROSITA Final Equatorial Depth Survey (eFEDS), with a sky area of 140 square degrees with depth equivalent to the equatorial patch of the final eROSITA all-sky survey, represen…
Testing galaxy feedback models with the first resolved profiles of the circumgalactic medium
Urmila Chadayammuri, Akos Bogdan, Benjamin Oppenheimer +3
The hot ( K) phase of the circumgalactic medium (CGM) contains a large fraction of baryons in galaxies. It also retains signatures of the processes that shaped the galaxies,…
Turbulent magnetic fields in merging clusters: A case study of Abell 2146
Urmila Chadayammuri, John ZuHone, Paul Nulsen +2
Kelvin-Helmholtz Instabilities (KHI) along contact discontinuities in galaxy clusters have been used to constrain the strength of magnetic fields in galaxy clusters, following the…
Constraining Merging Galaxy Clusters with X-ray and Lensing Simulations and Observations: The case of Abell 2146
Urmila Chadayammuri, John ZuHone, Paul Nulsen +5
Galaxy cluster mergers are a powerful laboratory for testing cosmological and astrophysical models. However, interpreting individual merging clusters depends crucially on their mer…
Fountains and storms: The role of AGN and mergers in disrupting the cool-core in the RomulusC simulation
Urmila Chadayammuri, Michael Tremmel, Daisuke Nagai +2
The intracluster medium (ICM) is a multi-phase environment, dynamically regulated by Active Galactic Nuclei (AGN), the motions of galaxies through it, and mergers with other cluste…
Probing Macro-Scale Gas Motions and Turbulence in Diffuse Cosmic Plasmas
Esra Bulbul, Massimo Gaspari, Gabriella Alvarez +31
Clusters of galaxies, the largest collapsed structures in the Universe, are located at the intersection of extended filaments of baryons and dark matter. Cosmological accretion ont…
Introducing RomulusC: A Cosmological Simulation of a Galaxy Cluster with Unprecedented Resolution
Michael Tremmel, Thomas R. Quinn, Angelo Ricarte +6
We present the first results from RomulusC, the highest resolution cosmological hydrodynamic simulation of a galaxy cluster run to date. RomulusC, a zoom-in simulation of a halo wi…
Mapping substructure in the HST Frontier Fields cluster lenses and in cosmological simulations
Priyamvada Natarajan, Urmila Chadayammuri, Mathilde Jauzac +14
We map the lensing-inferred substructure in the first three clusters observed by the Hubble Space Telescope Frontier Fields Initiative (HSTFF): Abell 2744 (z = 0.308), MACSJ0416, (…
The Scale Factor in the Universe with Dark Energy
M. V. Sazhin, O. S. Sazhina, U. Chadayammuri
Friedmans cosmological equations for the scale factor are analyzed for the Universe containing dark energy. The parameter of the equation of state of the dark energy is treated as…