Bent It Like FRs: Extended Radio AGN in the COSMOS Field and Their Large-Scale Environment

A fascinating topic in radio astronomy is how to associate the complexity of observed radio structures with their environment in order to understand their interplay and the reason for the plethora of radio structures found in surveys. In this project, we explore the distortion of the radio structure of Fanaroff–Riley (FR)-type radio sources in the VLA-COSMOS Large Project at 3 GHz and relate it to their large-scale environment. We quantify the distortion by using the angle formed between the jets/lobes of two-sided FRs, namely bent angle (BA). Our sample includes 108 objects in the redshift range 0.08<z<3, which we cross-correlate to a wide range of large-scale environments (X-ray galaxy groups, density fields, and cosmic web probes) in the COSMOS field. The median BA of FRs in COSMOS at zmed∼0.9 is 167.5−37.5+11.5 degrees. We do not find significant correlations between BA and large-scale environments within COSMOS covering scales from a few kpc to several hundred Mpc, nor between BA and host properties. Finally, we compare our observational data to magnetohydrodynamical (MHD) adaptive-mesh simulations ENZO-MHD of two FR sources at z = 0.5 and at z = 1. Although the scatter in BA of the observed data is large, we see an agreement between observations and simulations in the bent angles of FRs, following a mild redshift evolution with BA. We conclude that, for a given object, the dominant mechanism affecting the radio structures of FRs could be the evolution of the ambient medium, where higher densities of the intergalactic medium at lower redshifts as probed by our study allow more space for jet interactions.

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MODELING JET INTERACTIONS WITH THE AMBIENT MEDIUM

Acta Polytechnica ◽

10.14311/ap.2013.53.0683 ◽

2013 ◽

Vol 53 (A) ◽

pp. 683-686

Author(s):

J. H. Beall ◽

J. Guillory ◽

D. V. Rose ◽

Michael T. Wolff

Keyword(s):

Large Scale ◽

Ambient Medium ◽

Time Dependent ◽

Complex Structures ◽

Relativistic Hydrodynamic ◽

Astrophysical Jets ◽

Hydrodynamic Simulations ◽

Central Engine ◽

Interstellar Material ◽

Jet Interactions

Recent high-resolution (see, e.g., [13]) observations of astrophysical jets reveal complex structures apparently caused by ejecta from the central engine as the ejecta interact with the surrounding interstellar material. These observations include time-lapsed “movies” of both AGN and microquasars jets which also show that the jet phenomena are highly time-dependent. Such observations can be used to inform models of the jet–ambient-medium interactions. Based on an analysis of these data, we posit that a significant part of the observed phenomena come from the interaction of the ejecta with prior ejecta as well as interstellar material. In this view, astrophysical jets interact with the ambient medium through which they propagate, entraining and accelerating it. We show some elements of the modeling of these jets in this paper, including energy loss and heating via plasma processes, and large scale hydrodynamic and relativistic hydrodynamic simulations.

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XMM-Newton observations of elliptical galaxies in the local universe

Proceedings of the International Astronomical Union ◽

10.1017/s1743921310009178 ◽

2009 ◽

Vol 5 (H15) ◽

pp. 273-273

Author(s):

Ginevra Trinchieri

Keyword(s):

Globular Clusters ◽

Large Scale ◽

Spectral Characteristics ◽

Large Field ◽

Specific Class ◽

Early Type ◽

X Ray ◽

Compact Source ◽

Wide Range ◽

The Individual

XMM-Newton is well suited to the study of the X-ray properties of early-type galaxies: the wide energy band allows a characterization of the different components of the X-ray emission in galaxies, separating the gas from the compact source component through their spectral characteristics, and identifying low-luminosity absorbed AGNs; the large field of view allows a proper understanding of the large scale emission, and the separation between the galaxy and the surrounding group. Nonetheless, in spite of the much improved understanding of the X-ray characteristics of this class of sources, much of the original questions on the global X-ray properties of early-type galaxies remain. One in particular: how can we predict how much gas is there in any given galaxy? We have learned that the individual sources are tightly linked to the stellar component, both field stars and relative frequency of globular clusters. We have also learned that the central group galaxies, brighter and more extended, might represent a specific class of early-type galaxies, rather than the population as a whole. Yet we have not learned how to predict, from the stellar properties, how much hot gas a galaxy will have. Even a well selected class of sources, namely early type galaxies in isolation, where we can exclude the influence of the environment, appear to retain different amounts of the hot ISM produced by the stellar population, and display a wide range of Lx for their gaseous component for a relative narrow range of Lb, or mass [measured through LK], as shown by Fig. 1.

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QSO2 outflow characterization using data obtained with OSIRIS at the Gran Telescopio Canarias

Astronomy and Astrophysics ◽

10.1051/0004-6361/201935270 ◽

2019 ◽

Vol 626 ◽

pp. A89 ◽

Cited By ~ 1

Author(s):

Enrica Bellocchi ◽

Montserrat Villar Martín ◽

Antonio Cabrera–Lavers ◽

Bjorn Emonts

Keyword(s):

Large Scale ◽

Spatial Scales ◽

Host Galaxies ◽

Radio Structure ◽

Dynamical State ◽

Gas Kinematics ◽

Very Large Telescope ◽

Extended Radio ◽

Using Data ◽

S0 Galaxies

Context. Ionized outflows are ubiquitous in non-radio-loud obscured quasars (QSO2s) at different redshifts. However, the actual size of the outflows and their efficiency for gas ejection and star formation truncation are controversial. Large-scale (exceeding several kiloparsec) extended radio structures might be necessary to identify (even to trigger) outflow signatures across such large spatial scales. Aims. We search for large-scale ionized outflows associated with six optically selected QSO2 (five non-radio-loud and one radio-loud) at z ∼ 0.2−0.5, targeting objects with extended radio structures. We also investigate the dynamical state of the QSO2 host galaxies. Methods. We obtained data with the optical imager and long-slit spectrograph (OSIRIS) mounted on the 10.4m Gran Telescopio Canarias Spanish telescope (GTC) for these six QSO2 with the slit located along the radio axis. We traced the gas kinematics with the [OIII]λλ4959,5007 lines to investigate ionized outflows and characterize the dynamical state of the host galaxies. This second study was complemented with previously published spectroscopic data obtained with the multimode focal reducer and low dispersion spectrograph (FORS2) mounted on the Very Large Telescope (VLT) of 13 more QSO2 at similar z. Results. We identify ionized outflows in four out of the six QSO2 observed with the GTC. The outflows are spatially unresolved in two QSO2 and compact in a third (radial size of R = 0.8 ± 0.3 kpc). Of particular interest is the radio-quiet QSO2 SDSS 0741+3020 at z = 0.47. It is associated with a giant ∼112 kpc nebula. An ionized outflow probably induced by the radio structures has been detected along the axis defined by the central ∼1″ radio structure, extending up to at least ∼4 kpc from the active galactic nucleus (AGN). Turbulent gas (σ ∼ 130 km s−1) has also been detected across the giant gas nebula up to ∼40 kpc from the AGN. This turbulence may have been induced by outflows triggered by the interaction between a so-far undetected large-scale radio source and the nebula. Regarding the dynamical state of the host galaxies, we find that the majority of the QSO2 show v/σ < 1, implying that they are dominated by random motions (so-called dispersion-dominated systems). Most (17 of 19) fall in the area of the E/S0 galaxies in the dynamical diagram v/σ versus σ. None are consistent with spiral or disk galaxies.

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Extended X-ray emission in PKS 1718−649

Astronomy and Astrophysics ◽

10.1051/0004-6361/201833064 ◽

2018 ◽

Vol 612 ◽

pp. L4 ◽

Cited By ~ 5

Author(s):

T. Beuchert ◽

A. Rodríguez-Ardila ◽

V. A. Moss ◽

R. Schulz ◽

M. Kadler ◽

...

Keyword(s):

Large Scale ◽

Star Formation Rate ◽

Formation Rate ◽

Effective Area ◽

Radio Spectrum ◽

Host Galaxy ◽

X Rays ◽

Radio Structure ◽

X Ray ◽

Close Proximity

PKS 1718−649 is one of the closest and most comprehensively studied candidates of a young active galactic nucleus (AGN) that is still embedded in its optical host galaxy. The compact radio structure, with a maximal extent of a few parsecs, makes it a member of the group of compact symmetric objects (CSO). Its environment imposes a turnover of the radio synchrotron spectrum towards lower frequencies, also classifying PKS 1718−649 as gigahertz-peaked radio spectrum (GPS) source. Its close proximity has allowed the first detection of extended X-ray emission in a GPS/CSO source with Chandra that is for the most part unrelated to nuclear feedback. However, not much is known about the nature of this emission. By co-adding all archival Chandra data and complementing these datasets with the large effective area of XMM-Newton, we are able to study the detailed physics of the environment of PKS 1718−649. Not only can we confirm that the bulk of the ≲kiloparsec-scale environment emits in the soft X-rays, but we also identify the emitting gas to form a hot, collisionally ionized medium. While the feedback of the central AGN still seems to be constrained to the inner few parsecs, we argue that supernovae are capable of producing the observed large-scale X-ray emission at a rate inferred from its estimated star formation rate.

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Kiruna-Type Ore as a Novel Precursor for Large-Scale Production of Small Uniform Iron Oxide Nanoparticles

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2020.18438 ◽

2020 ◽

Vol 20 (10) ◽

pp. 6525-6531

Author(s):

Majid Mostaghelchi ◽

Jani Kotakoski ◽

Christian Rentenberger ◽

Christian L. Lengauer

Keyword(s):

Iron Oxide ◽

Iron Oxide Nanoparticles ◽

Large Scale ◽

Critical Size ◽

Raw Material ◽

Oxide Nanoparticles ◽

Scale Production ◽

X Ray ◽

Mechanical Attrition ◽

Wide Range

The wide range of actual and potential applications of nanoparticles, highlight the necessity of a reliable production method for both quality and quantity of the products. Mechanical attrition is one of the first well-known techniques used to produce nanoparticles. However, these approaches have been restricted to produce uniform particles below the critical size of 15 nm because of the attrition balance limit. This paper introduces the magnetite–silicate raw material of a Kiruna-type ore deposit as a novel precursor, which enables the production of small iron oxide nanoparticles below the critical size by mechanical attrition. X-ray fluorescence (XRF), powder X-ray diffractometry (pXRD), dynamic light scattering (DLS) and transmission electron microscopy (TEM) were used for characterization of the precursor and obtained nanoparticles. The results indicate that the particles with a mean diameter of 10.7(2.7) nm consist of mainly less than one crystallite. The significant size reduction below the attrition balance limit can be attributed to the quartz content of the raw material, which operated as supporting micro-balls for transferring the energy during the milling process.

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Blanket and Selective Copper CVD from Cu (Fod)2 For Multilevel Metallization

MRS Proceedings ◽

10.1557/proc-181-79 ◽

1990 ◽

Vol 181 ◽

Cited By ~ 5

Author(s):

Alain E. Kaloyeros ◽

Arjun N. Saxena ◽

Kenneth Brooks ◽

Sumanta Ghosh ◽

Eric Eisenbraun

Keyword(s):

Large Scale ◽

Chemical Vapor ◽

Precursor Chemistry ◽

Limiting Factors ◽

Organic Chemical ◽

Working Pressure ◽

X Ray ◽

Wide Range ◽

Large Scale Integration ◽

Scale Integration

ABSTRACTAs the focus of integration technology inevitably shifts from the present very large scale integration (VLSI) to ultra large scale integration (ULSI) schemes, thus leading to continuous decrease in circuit dimensions, the limitations of present multilevel metallization technologies become increasingly important. Because of the appreciably higher speeds and more complex multi-functional layering involved in the newest ULSI circuits, the electrical resistance and capacitance of presently used interconnects and their electromigration and stress resistance stand as major limiting factors to signal processing throughput. In this paper, some recent results achieved by the present investigators in their studies of blanket and selective low-temperature metal-organic chemical vapor deposition (LTMOCVD) of copper for potential use in multilevel metallizations in ULSIC’s are presented. The films were produced at 300–400°C in atmospheres of pure H2 or Ar from the β-diketonate precursor bis(6, 6, 7,7, 8, 8, 8-heptafluoro-2, 2-dimethy1-3, 5-octanediono)copper(II), Cu(fod)2. The films were analyzed by x-ray diffraction (XRD), Rutherford Backscattering (RBS), Auger electron spectroscopy (AES), scanning electron microscopy (SEM), energy-dispersive x-ray spectroscopy (EDXS), and four-point resistivity probe. The results of these studies showed that films deposited on metallic substrates were uniform, continuous, adherent, highly pure, and exhibited very low resistivity, as low as 1.8 μΩcm for films deposited in pure H2 atmosphere. Preliminary investigations of selective LTMOCVD of copper showed that selectivity is indeed possible, but is a function of a wide range of parameters that include reactor geometry, substrate type and temperature, working pressure, type of carrier gas, and precursor chemistry.

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FR-type radio sources at 3 GHz VLA-COSMOS: Relation to physical properties and large-scale environment

Astronomy and Astrophysics ◽

10.1051/0004-6361/202039488 ◽

2021 ◽

Vol 648 ◽

pp. A102

Author(s):

E. Vardoulaki ◽

E. F. Jiménez Andrade ◽

I. Delvecchio ◽

V. Smolčić ◽

E. Schinnerer ◽

...

Keyword(s):

Star Formation ◽

Physical Properties ◽

Large Scale ◽

Learning Algorithm ◽

Control Sample ◽

X Rays ◽

Radio Luminosity ◽

Radio Structure ◽

X Ray ◽

Jet Power

Context. Radio active galactic nuclei (AGN) are traditionally separated into two Fanaroff-Riley (FR) type classes, edge-brightened FRII sources or edge-darkened FRI sources. With the discovery of a plethora of radio AGN of different radio shapes, this dichotomy is becoming too simplistic in linking the radio structure to the physical properties of radio AGN, their hosts, and their environment. Aims. We probe the physical properties and large-scale environment of radio AGN in the faintest FR population to date, and link them to their radio structure. We use the VLA-COSMOS Large Project at 3 GHz (3 GHz VLA-COSMOS), with a resolution and sensitivity of 0.″75 and 2.3 μJy beam−1 to explore the FR dichotomy down to μJy levels. Methods. We classified objects as FRIs, FRIIs, or hybrid FRI/FRII based on the surface-brightness distribution along their radio structure. Our control sample was the jet-less/compact radio AGN objects (COM AGN), which show excess radio emission at 3 GHz VLA-COSMOS exceeding what is coming from star-formation alone; this sample excludes FRs. The largest angular projected sizes of FR objects were measured by a machine-learning algorithm and also by hand, following a parametric approach to the FR classification. Eddington ratios were calculated using scaling relations from the X-rays, and we included the jet power by using radio luminosity as a probe. Furthermore, we investigated their host properties (star-formation ratio, stellar mass, morphology), and we explore their incidence within X-ray galaxy groups in COSMOS, and in the density fields and cosmic-web probes in COSMOS. Results. Our sample is composed of 59 FRIIs, 32 FRI/FRIIs, 39 FRIs, and 1818 COM AGN at 0.03 ≤ z ≤ 6. On average, FR objects have similar radio luminosities (L3 GHz ∼ 1023 W Hz−1 sr−1), spanning a range of 1021−26 W Hz−1 sr−1, and they lie at a median redshift of z ∼ 1. The median linear projected size of FRIIs is 106.636.9238.2 kpc, larger than that of FRI/FRIIs and FRIs by a factor of 2−3. The COM AGN have sizes smaller than 30 kpc, with a median value of 1.71.54.7 kpc. The median Eddington ratio of FRIIs is 0.0060.0050.007, a factor of 2.5 less than in FRIs and a factor of 2 higher than in FRI/FRII. When the jet power is included, the median Eddington ratios of FRII and FRI/FRII increase by a factor of 12 and 15, respectively. FRs reside in their majority in massive quenched hosts (M* > 1010.5 M⊙), with older episodes of star-formation linked to lower X-ray galaxy group temperatures, suggesting radio-mode AGN quenching. Regardless of their radio structure, FRs and COM AGN are found in all types and density environments (group or cluster, filaments, field). Conclusions. By relating the radio structure to radio luminosity, size, Eddington ratio, and large-scale environment, we find a broad distribution and overlap of FR and COM AGN populations. We discuss the need for a different classification scheme, that expands the classic FR classification by taking into consideration the physical properties of the objects rather than their projected radio structure which is frequency-, sensitivity- and resolution-dependent. This point is crucial in the advent of current and future all-sky radio surveys.

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DICOM Imaging Router: An Open Deep Learning Framework for Classification of Body Parts from DICOM X-ray Scans

10.1101/2021.08.13.21261945 ◽

2021 ◽

Author(s):

Hieu H. Pham ◽

Dung V. Do ◽

Ha Q. Nguyen

Keyword(s):

Deep Learning ◽

Large Scale ◽

Imaging Modality ◽

The Body ◽

Superior Performance ◽

Body Parts ◽

Deep Convolutional Neural Networks ◽

X Ray ◽

Wide Range ◽

Dicom Imaging

AbstractX-ray imaging in Digital Imaging and Communications in Medicine (DICOM) format is the most commonly used imaging modality in clinical practice, resulting in vast, non-normalized databases. This leads to an obstacle in deploying artificial intelligence (AI) solutions for analyzing medical images, which often requires identifying the right body part before feeding the image into a specified AI model. This challenge raises the need for an automated and efficient approach to classifying body parts from X-ray scans. Unfortunately, to the best of our knowledge, there is no open tool or framework for this task to date. To fill this lack, we introduce a DICOM Imaging Router that deploys deep convolutional neural networks (CNNs) for categorizing unknown DICOM X-ray images into five anatomical groups: abdominal, adult chest, pediatric chest, spine, and others. To this end, a large-scale X-ray dataset consisting of 16,093 images has been collected and manually classified. We then trained a set of state-of-the-art deep CNNs using a training set of 11,263 images. These networks were then evaluated on an independent test set of 2,419 images and showed superior performance in classifying the body parts. Specifically, our best performing model (i.e., MobileNet-V1) achieved a recall of 0.982 (95% CI, 0.977– 0.988), a precision of 0.985 (95% CI, 0.975–0.989) and a F1-score of 0.981 (95% CI, 0.976–0.987), whilst requiring less computation for inference (0.0295 second per image). Our external validity on 1,000 X-ray images shows the robustness of the proposed approach across hospitals. These remarkable performances indicate that deep CNNs can accurately and effectively differentiate human body parts from X-ray scans, thereby providing potential benefits for a wide range of applications in clinical settings. The dataset, codes, and trained deep learning models from this study will be made publicly available on our project website at https://vindr.ai/datasets/bodypartxr.

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High-Resolution Numerical Simulation and Analysis of Mach Reflection Structures in Detonation Waves in Low-Pressure H2–O2–Ar Mixtures: A Summary of Results Obtained with the Adaptive Mesh Refinement Framework AMROC

Journal of Combustion ◽

10.1155/2011/738969 ◽

2011 ◽

Vol 2011 ◽

pp. 1-18 ◽

Cited By ~ 34

Author(s):

Ralf Deiterding

Keyword(s):

Numerical Simulation ◽

Adaptive Mesh Refinement ◽

Large Scale ◽

Mach Reflection ◽

Adaptive Mesh ◽

Low Pressure ◽

Detonation Waves ◽

Parallel Simulations ◽

Wide Range ◽

Complex Boundaries

Numerical simulation can be key to the understanding of the multidimensional nature of transient detonation waves. However, the accurate approximation of realistic detonations is demanding as a wide range of scales needs to be resolved. This paper describes a successful solution strategy that utilizes logically rectangular dynamically adaptive meshes. The hydrodynamic transport scheme and the treatment of the nonequilibrium reaction terms are sketched. A ghost fluid approach is integrated into the method to allow for embedded geometrically complex boundaries. Large-scale parallel simulations of unstable detonation structures of Chapman-Jouguet detonations in low-pressure hydrogen-oxygen-argon mixtures demonstrate the efficiency of the described techniques in practice. In particular, computations of regular cellular structures in two and three space dimensions and their development under transient conditions, that is, under diffraction and for propagation through bends are presented. Some of the observed patterns are classified by shock polar analysis, and a diagram of the transition boundaries between possible Mach reflection structures is constructed.

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Covering complete proteomes with X-ray structures: a current snapshot

Acta Crystallographica Section D Biological Crystallography ◽

10.1107/s1399004714019427 ◽

2014 ◽

Vol 70 (11) ◽

pp. 2781-2793 ◽

Cited By ~ 23

Author(s):

Marcin J. Mizianty ◽

Xiao Fan ◽

Jing Yan ◽

Eric Chalmers ◽

Christopher Woloschuk ◽

...

Keyword(s):

Homology Modeling ◽

Structure Determination ◽

Large Scale ◽

Structural Model ◽

Target Selection ◽

Three Dimensional ◽

X Ray ◽

X Ray Crystallography ◽

Knowledge Based ◽

Wide Range

Structural genomics programs have developed and applied structure-determination pipelines to a wide range of protein targets, facilitating the visualization of macromolecular interactions and the understanding of their molecular and biochemical functions. The fundamental question of whether three-dimensional structures of all proteins and all functional annotations can be determined using X-ray crystallography is investigated. A first-of-its-kind large-scale analysis of crystallization propensity for all proteins encoded in 1953 fully sequenced genomes was performed. It is shown that current X-ray crystallographic knowhow combined with homology modeling can provide structures for 25% of modeling families (protein clusters for which structural models can be obtained through homology modeling), with at least one structural model produced for each Gene Ontology functional annotation. The coverage varies between superkingdoms, with 19% for eukaryotes, 35% for bacteria and 49% for archaea, and with those of viruses following the coverage values of their hosts. It is shown that the crystallization propensities of proteomes from the taxonomic superkingdoms are distinct. The use of knowledge-based target selection is shown to substantially increase the ability to produce X-ray structures. It is demonstrated that the human proteome has one of the highest attainable coverage values among eukaryotes, and GPCR membrane proteins suitable for X-ray structure determination were determined.

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