A5051230038- Galaxies: Formation, Evolution, Phenomena
- Astrophysics and Star Formation Studies
- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astrophysical Phenomena and Observations
- Astrophysics and Cosmic Phenomena
- Gamma-ray bursts and supernovae
- Cosmology and Gravitation Theories
- Atomic and Molecular Physics
- Spectroscopy and Laser Applications
- Astronomical Observations and Instrumentation
- History and Developments in Astronomy
- Solar and Space Plasma Dynamics
- Adaptive optics and wavefront sensing
- Plant Water Relations and Carbon Dynamics
- Phase Equilibria and Thermodynamics
- Dark Matter and Cosmic Phenomena
- Astro and Planetary Science
- Gas Dynamics and Kinetic Theory
- Radio Astronomy Observations and Technology
- Ionosphere and magnetosphere dynamics
- Space Science and Extraterrestrial Life
- Scientific Research and Discoveries
- High-pressure geophysics and materials
- Pulsars and Gravitational Waves Research
Michigan State University
2016-2025
Carnegie Observatories
2013
University of Virginia
2011
Center for Astrophysics Harvard & Smithsonian
2011
University of Waterloo
2011
California Institute of Technology
1992-2007
University of California, Berkeley
2007
Optica
2007
Harvard University Press
2007
Carnegie Institution for Science
2007
view Abstract Citations (781) References (39) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Accretion Disk Winds from Active Galactic Nuclei Murray, N. ; Chiang, J. Grossman, S. A. Voit, G. M. We present a dynamical model in which the broad absorption lines seen some quasar spectra form smooth nonspherical wind an accretion disk. On inner edge of this wind, at r ‚âç 1016 cm for 108 Msun black hole, entrained dense gas blocks soft X-rays but transmits...
The most successful cosmological models to date envision structure formation as a hierarchical process in which gravity is constantly drawing lumps of matter together form increasingly larger structures. Clusters galaxies currently sit atop this hierarchy the largest objects that have had time collapse under influence their own gravity. Thus appearance on cosmic scene also relatively recent. Two features clusters make them uniquely useful tracers evolution. First, are biggest things whose...
We present a systematic analysis of 43 nearby galaxy groups (kT500 = 0.7–2.7 keV or M500 1013–1014 h−1 M☉, 0.012 <z< 0.12), based on Chandra archival data. With robust background subtraction and modeling, we trace gas properties to at least r2500 for all groups. For 11 groups, can be robustly derived r500. an additional 12 derive r1000 estimate r500 from extrapolation. show that in spite the large variation temperature profiles inside 0.15 r500, these are similar > consistent with "universal...
We present radial entropy profiles of the intracluster medium (ICM) for a collection 239 clusters taken from Chandra X-ray Observatory's Data Archive. Entropy is great interest because it controls ICM global properties and records thermal history cluster. therefore useful quantity studying effects feedback on cluster environment investigating any breakdown self-similarity. find that most are well-fit by model which power-law at large radii approaches constant value small radii: K(r) = K0 +...
(Abridged) We examine the radial entropy distribution and its scaling using 31 nearby galaxy clusters from Representative XMM-Newton Cluster Structure Survey (REXCESS). The profiles are robustly measured at least out to R_1000 in all systems R_500 13 systems. Compared theoretical expectations, observed distributions show a mass-dependent excess that is greater extends larger radii lower mass At R_500, dependence both negligible within uncertainties. Mirroring this behaviour, of gas shallower...
The universe's biggest galaxies have both vast atmospheres and supermassive central black holes. This article reviews how those two components of a large galaxy couple regulate the galaxy's star formation rate. Models interactions between hole large-scale atmosphere suggest that energy released as cold gas clouds accrete onto suspends in state is marginally stable to clouds. A growing body observational evidence indicates many massive galaxies, ranging from huge clusters down our own Milky...
Context.The largest uncertainty for cosmological studies using clusters of galaxies is introduced by our limited knowledge the statistics galaxy cluster structure, and scaling relations between observables mass.
Our Chandra X-Ray Observatory archival study of intracluster entropy in a sample 222 galaxy clusters shows that Hα and radio emission from the brightest cluster are much more pronounced when cluster's core gas is ≲30 keV cm2. The prevalence below this threshold indicates it marks dichotomy between can harbor multiphase star formation their cores those cannot. fact strong central also appears boundary suggests AGN feedback turns on medium starts to condense, strengthening case for as...
The radial entropy profile of the hot gas in clusters galaxies tends to follow a power law radius outside cluster core. Here we present simple formula giving both normalization and slope for power-law profiles that form absence non-gravitational processes such as radiative cooling subsequent feedback. It is based on seventy-one drawn from four separate cosmological simulations, two using smoothed-particle hydrodynamics (SPH) adaptive-mesh refinement (AMR), can be used baseline assessing...
A Chandra image of the central 100 kpc Abell 2597 cluster galaxies shows bright irregular X-ray emission within dominant galaxy (CDG) and two low surface brightness cavities located 30 from nucleus CDG. Unlike commonly seen in other clusters, "ghost" are not coincident with radio source. Instead, they appear to be associated faint extended a deep Very Large Array map. We interpret ghost as buoyantly rising relics outburst that occurred between 50 Myr ago. The demography few clusters studied...
Infrared spectra of dusty galactic environments often contain emission features attributed to polycyclic aromatic hydrocarbons or PAHs, which can be considered very small grains large molecules. Although IR starburst galaxies almost always show these features, similar active are usually featureless. Even in those that do exhibit PAH emission, the PAHs still appear eradicated from nuclear region. This dichotomy suggests destroyed by intense hard radiation field an AGN. Laboratory experiments...
We present the discovery of a 40 kpc Hα tail and at least 29 emission-line objects downstream star-forming galaxy, ESO 137-001, in rich, nearby cluster A3627. The galaxy is known to possess dramatic 70 X-ray tail. detected coincides positionally with emission sharply truncated on front sides near nucleus, indicating significant ram pressure stripping. 137-001 thus first late-type unambiguously have both an are all distributed projected distances up 39 from galaxy. From analysis Hαoff frame...
We present a systematic investigation of X-ray thermal coronae in 157 early-type galaxies and 22 late-type from survey 25 hot (kT>3 keV), nearby (z<0.05) clusters, based on CHANDRA archival data. Cool galactic (kT=0.5-1.1 keV generally) have been found to be very common, >60% NIR selected that are more luminous than 2L*, >40% L* < L_Ks 2L* galaxies. These embedded clusters generally smaller (1.5-4 kpc radii), less (100, which implies the gas is magnetized magnetic field plays...
We report ALMA Early Science observations of the Abell 1835 brightest cluster galaxy (BCG) in CO (3-2) and (1-0) emission lines. detect 5E10 solar masses molecular gas within 10 kpc BCG. Its velocity width ~130 km/s FWHM is too narrow to be supported by dynamical pressure. The may instead a rotating, turbulent disk oriented nearly face-on. forming stars at rate 100-180 per year. Roughly 1E10 projected 3-10 north-west east nucleus with line sight velocities lying between -250 +480 respect...
Numerical simulations of active galactic nuclei (AGNs) feedback in cool-core galaxy clusters have successfully avoided classical cooling flows, but often produce too much cold gas. We perform adaptive mesh that include momentum-driven AGN feedback, self-gravity, star formation, and stellar focusing on the interplay between cooling, heating, formation an isolated cluster. Cold clumps triggered by jets turbulence form filamentary structures tens kpc long. This gas feeds both supermassive black...
Abstract We present Atacama Large Millimeter/submillimeter Array and Multi-Unit Spectroscopic Explorer observations of the brightest cluster galaxy in Abell 2597, a nearby ( z = 0.0821) cool core galaxies. The data map kinematics three billion solar mass filamentary nebula that spans innermost 30 kpc galaxy’s core. Its warm ionized cold molecular components are both cospatial comoving, consistent with hypothesis optical traces envelopes many clouds drift velocity field hot X-ray atmosphere....
We provide an analytic framework for interpreting observations of multiphase circumgalactic gas that is heavily informed by recent numerical simulations thermal instability and precipitation in cool-core galaxy clusters. start considering the local conditions required formation via two different modes: (1) uplift ambient galactic outflows, (2) condensation a stratified stationary medium which balance explicitly maintained. Analytic exploration these modes provides insights into relationships...
We present profiles of temperature (Tx), gas mass, and hydrostatic mass estimated from new archival X-ray observations CLASH clusters. compare measurements derived XMM Chandra with one another both to gravitational lensing HST ground-based data. Radial electron density enclosed are nearly identical, indicating that differences in masses inferred arise Tx measurements. Encouragingly, cluster Txs consistent at ~100-200 kpc radii but systematically decline relative larger radii. The angular...
view Abstract Citations (194) References (37) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Low-Ionization Broad Absorption Lines in Quasars Voit, G. M. ; Weymann, Ray J. Korista, Kirk T. About 10% of optically selected radio-quiet quasars have broad high- ionization absorption lines and are known as line quasars, or BALQSOs. 15% these BALQSOs also low-ionization Mg II Although uncommon surveys, appear to be much more common IR-selected samples might...
We present a set of cluster models that link the present-day properties clusters to processes govern galaxy formation. These treat entropy distribution intracluster medium as its most fundamental property. Because convection strives establish an gradient rises with radius, observable relaxed depend entirely on dark-matter potential and uncondensed gas. Guided by simulations, we compute arises in absence radiative cooling supernova heating assuming gas-density would be identical dark matter....
The entropy distribution of the intracluster medium and shape its confining potential well completely determine X-ray properties a relaxed cluster galaxies, motivating us to explore origin describe how it develops in terms some simple models. We present an analytical model for smooth accretion, including both preheating radiative cooling, that links cluster's mass accretion history shows overproduces observed massive clusters by factor ~2-3, depending on rate. Any inhomogeneity accreting gas...
We present the discovery of spectacular double X-ray tails associated with ESO137-001 and a possibly heated tail ESO137-002, both late-type galaxies in closest rich cluster Abell 3627. A deep Chandra observation allows us for first time to examine spatial spectral properties such detail. Besides known bright that extends ~ 80 kpc from ESO137-001, fainter narrower secondary similar length was surprisingly revealed. There is little temperature variation along tails. also identified six point...