A5012545044- Galaxies: Formation, Evolution, Phenomena
- Astronomy and Astrophysical Research
- Astrophysical Phenomena and Observations
- Gamma-ray bursts and supernovae
- Stellar, planetary, and galactic studies
- Astrophysics and Cosmic Phenomena
- Adaptive optics and wavefront sensing
- Astronomical Observations and Instrumentation
- Pulsars and Gravitational Waves Research
- Cosmology and Gravitation Theories
- Solar and Space Plasma Dynamics
- Astrophysics and Star Formation Studies
- Black Holes and Theoretical Physics
- Data Visualization and Analytics
- Plant Water Relations and Carbon Dynamics
- Statistical and numerical algorithms
- Scientific Research and Discoveries
- Radio Astronomy Observations and Technology
- Advanced Fluorescence Microscopy Techniques
- scientometrics and bibliometrics research
- Advanced Data Storage Technologies
- Computational and Text Analysis Methods
- Genomics and Phylogenetic Studies
- Astro and Planetary Science
Center for Astrophysics Harvard & Smithsonian
2022-2024
Max Planck Institute for Astronomy
2024
Yale University
2017-2022
Smithsonian Astrophysical Observatory
2021
Abstract We conduct a systematic tidal disruption event (TDE) demographics analysis using the largest sample of optically selected TDEs. A flux-limited, spectroscopically complete 33 TDEs is constructed Zwicky Transient Facility over 3 yr (from 2018 October to 2021 September). infer black hole (BH) mass ( M BH ) with host galaxy scaling relations, showing that ranges from 10 5.1 ⊙ 8.2 . developed survey efficiency corrected maximum volume method rates. The rest-frame g -band luminosity...
Abstract While supermassive black holes (SMBHs) are widely observed in the nearby and distant Universe, their origin remains debated with two viable formation scenarios light heavy seeds. In seeding model, seed of first SMBHs form from collapse massive stars masses 10–100 M ⊙ , while model posits 10 4–5 seeds direct collapse. The detection at redshifts z ≳ 10, edging closer to epoch, provides critical observational discrimination between these scenarios. Here, we focus on JWST-detected...
We present the first results from RomulusC, highest resolution cosmological hydrodynamic simulation of a galaxy cluster run to date. zoom-in halo with $z=0$ mass $10^{14}$ M$_{\odot}$, is same sub-grid physics and as Romulus25 (Tremmel et al. 2017). With unprecedented spatial resolution, RomulusC represents unique opportunity study evolution galaxies in dense environments down dwarf masses. demonstrate that an intracluster medium (ICM) consistent observations. The star formation history...
We map the lensing-inferred substructure in first three clusters observed by Hubble Space Telescope Frontier Fields (HSTFF) Initiative: Abell 2744 (z = 0.308), MACSJ 0416, 0.396) and 1149 0.543). Statistically resolving dark matter subhaloes down to |${\sim }10^{9.5}\,{{\rm {M}_{{\odot}}}}$|, we compare derived subhalo mass functions (SHMFs) theoretical predictions from analytical models with numerical simulations a Lambda cold (LCDM) cosmology. Mimicking our observational cluster member...
Abstract The hot (>10 6 K) phase of the circumgalactic medium (CGM) contains a large fraction baryons in galaxies. It also retains signatures processes that shaped galaxies, such as feedback from active galactic nuclei and supernovae, offers uniquely powerful way to constrain theoretical models feedback. is, however, notoriously difficult detect. By stacking 2643 optically selected galaxies eROSITA Final Equatorial Depth Survey, we present spatially resolved properties extended CGM both...
Abstract Although weak lensing (WL) is a powerful method to estimate galaxy cluster mass without any dynamical assumptions, model bias can arise when the density profile departs from assumed profile. In merging system, expected become most severe because constituent halos undergo significant structural changes. this study, we investigate WL in binary mergers using suite of idealized hydrodynamical simulations. Realistic shear catalogs are generated by matching source properties, such as...
Observations of quasars reveal that many supermassive black holes (BHs) were in place less than 700 million years after the Big Bang. However, origin first BHs remains a mystery. Seeds are postulated to be either light (i.e., $10-100~\rm{M_{\odot}})$, remnants stars or heavy $10^4-10^5~\rm{M_{\odot}})$, originating from direct collapse gas clouds. Harnessing recent data Chandra X-ray Observatory, we report detection an X-ray-luminous massive BH gravitationally-lensed galaxy identified by...
We conduct a systematic tidal disruption event (TDE) demographics analysis using the largest sample of optically selected TDEs. A flux-limited, spectroscopically complete 33 TDEs is constructed Zwicky Transient Facility over three years (from October 2018 to September 2021). infer black hole (BH) mass ($M_{\rm BH}$) with host galaxy scaling relations, showing that $M_{\rm BH}$ ranges from $10^{5.1}\,M_\odot$ $10^{8.2}\,M_\odot$. developed survey efficiency corrected maximum volume method...
ABSTRACT The intracluster medium (ICM) is a multiphase environment, dynamically regulated by active galactic nuclei (AGN), the motions of cluster galaxies, and mergers with other clusters or groups. AGN provide central heating source capable preventing runaway cooling flows quenching star formation, but how they achieve this still poorly understood. We investigate effects feedback on ICM using high-resolution romulusc cosmological simulation 1014 M⊙ galaxy cluster. demonstrate that regulates...
Abstract Dwarf galaxies are promising test beds for constraining models of supermassive and intermediate-mass black holes (MBHs) via their BH occupation fraction (BHOF). Disentangling seeding from the confounding effects mass assembly over a Hubble time is challenging problem that we tackle in this study with suite semianalytical (SAMs). We show how measured BHOF depends on lowest or active galactic nucleus (AGN) luminosity achieved by survey. To tell apart, need to detect model all AGNs...
ABSTRACT Galaxy cluster mergers are a powerful laboratory for testing cosmological and astrophysical models. However, interpreting individual merging clusters depends crucially on their merger configuration, defined by the masses, velocities, impact parameters, orientation of axis with respect to plane sky. In this work, we investigate parameters X-ray emitting intracluster medium gravitational lensing maps using suite idealized simulations binary performed gamer-2 code. As test case, focus...
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 first time, we resolve and measure width shocks. The best-fit for bow is 17+/-1 upstream 10.7+/-0.3 kpc. A narrow collisionless will appear broader in projection if its smooth shape warped by local gas motions. show that both widths are consistent with shocks blurred motions 290+/-30 km/s. forms later on than therefore expected to be significantly...
Abstract 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 may retain memory assembly history their (BHs), probing BH occupation fraction local might offer insights into growth and seeding mechanisms first BHs. In this work, we exploit Western half eROSITA all-sky survey (covering 20,000 deg 2 ) compile a catalog accreting SMBHs ( D < 200 Mpc) galaxies. Cleaning...
ABSTRACT Galaxy cluster mass functions are a function of cosmology, but is not direct observable, and systematic errors abound in all its observable proxies. Mass-free inference can bypass this challenge, it requires large suites simulations spanning range cosmologies models for directly quantities. In work, we devise U-net – an image-to-image machine learning algorithm to ‘paint’ the illustristng model baryons on dark matter-only (DMO) galaxy clusters. Using 761 clusters with M200c ≳ 1014...
ABSTRACT Kelvin–Helmholtz instabilities (KHI) along contact discontinuities in galaxy clusters have been used to constrain the strength of magnetic fields clusters, following assumption that, as field lines drape around interface between cold and hot phases, their tension resists growth perturbations. This has observed simulations rigid objects moving through magnetized media sloshing then applied interpreting observations merger fronts. Using a suite magnetohydrodynamic (MHD) binary cluster...
Friedmans cosmological equations for the scale factor are analyzed Universe containing dark energy. The parameter of equation state energy is treated as an arbitrary constant whose value lies within interval $w \in [-1.5, -0.5]$, limits which set by current observations. A unified analytic solution obtained a function physical and conformal time. We obtain approximated solutions to accuracy better then 1%. This measurement errors global density parameters therefore suitable models our...
The hot ($>10^6$ K) phase of the circumgalactic medium (CGM) contains a large fraction baryons in galaxies. It also retains signatures processes that shaped galaxies, such as feedback from active galactic nuclei (AGNs) and supernovae, offers uniquely powerful way to constrain theoretical models feedback. is, however, notoriously difficult detect. By stacking 2643 optically selected galaxies eROSITA Final Equatorial Depth Survey (eFEDS), we present spatially resolved properties extended...
ABSTRACT The eROSITA Final Equatorial Depth Survey (eFEDS), with a sky area of 140 square degrees depth equivalent to the equatorial patch final all-sky survey, represents largest continuous non-full-sky X-ray fields to-date, making it premier data set for measuring angular power spectrum. In this work, we measure spectrum galaxy clusters and groups in eFEDS field. We show that measured is consistent past observations, including ROSAT All Sky Survey, Chandra COSMOS Bootes fields. predictions...
JKCS041 ($z=1.8$) is one of the most distant galaxy cluster systems known, seen when Universe was less than 4 billion years old. Recent Sunyaev-Zeldovich (SZ) observations show a temperature decrement that expected based on mass estimates system from X-ray, weak gravitational lensing and richness measurements. In this paper we seek to explain observables - in particular low SZ single peak, projected offset between X-ray peaks $\approx$220 kpc, gas measurements estimate. We use GAMER-2...
While supermassive black holes (BHs) are widely observed in the nearby and distant universe, their origin remains debated with two viable formation scenarios light heavy seeds. In seeding model, first BHs form from collapse of massive stars masses $10-100 \ \rm{M_{\odot}}$, while model posits $10^{4-5} \rm{M_{\odot}}$ seeds direct collapse. The detection at redshifts $z\gtrsim10$, edging closer to epoch, provides critical observational discrimination between these scenarios. Here, we focus...
Galaxy cluster mergers are representative of a wide range physics, making them an excellent probe the properties dark matter and ionized plasma intracluster medium. To date, most studies have focused on occurring in plane sky, where morphological features can be readily identified. allow study with arbitrary orientation, we assembled multi-probe data for eight-cluster ICM-SHOX sample sensitive to both morphology line sight velocity. The first paper (Silich+2023) provided overview our...
Although supermassive black holes (SMBHs) reside in the heart of virtually every massive galaxy, it remains debated whether dwarf galaxies also commonly host SMBHs. Because low-mass may retain a memory assembly history their holes, probing hole occupation fraction local might offer insights into growth and seeding mechanisms first holes. In this work, we exploit Western half eROSITA all-sky survey (covering $20,000~\rm{deg^2}$) compile catalog accreting SMBHs ($D<200$~Mpc) galaxies. After...
Abstract Galaxy cluster mergers are rich sources of information to test astrophysics and cosmology. However, produce complex projected signals that difficult interpret physically from individual observational probes. Multi-probe constraints on the gas dark matter (DM) components necessary infer merger parameters otherwise degenerate. We present Improved Constraints Mergers with SZ, Hydrodynamical simulations, Optical, X-ray (ICM-SHOX), a systematic framework jointly multiple quantitatively...