scholarly journals AGES Observations of Abell 1367

2007 ◽  
Vol 3 (S244) ◽  
pp. 350-351
Author(s):  
L. Cortese ◽  
R. F. Minchin ◽  
R. R. Auld ◽  
J. I. Davies ◽  
B. Catinella ◽  
...  
Keyword(s):  
Optical Imaging ◽  
Large Scale ◽  
Striking Difference ◽  
Scaling Relations ◽  
Local Cluster ◽  
X Ray ◽  
The Core ◽  
Cluster Of Galaxies ◽  
Abell Cluster ◽  
Galaxy Environment

AbstractWe present 21 cm observations of 5×1 square degrees centered on the local Abell cluster 1367 obtained as part of the Arecibo Galaxy Environment Survey. This represents the first HI selected sample covering the core and the outskirts of a local cluster of galaxies. Combining the HI data with SDSS optical imaging we show that in HI selected samples follow scaling relations similar to the ones usually observed in optically selected samples. The most striking difference between HI and optically selected samples resides in their large scale distribution: while optical and X-ray observations trace the cluster potential very well, at radio wavelengths there is almost no evidence of the cluster presence.

Large scale extended X-ray emission from the Virgo cluster of galaxies

Nature ◽  
1989 ◽  
Vol 340 (6231) ◽  
pp. 289-290 ◽  
Author(s):  
S. Takano ◽  
H. Awaki ◽  
K. Koyama ◽  
H. Kunieda ◽  
Y. Tawara ◽  
...  
Keyword(s):  
Large Scale ◽  
Virgo Cluster ◽  
X Ray ◽  
Cluster Of Galaxies

scholarly journals Cool X-ray emitting gas in the core of the Centaurus cluster of galaxies

2008 ◽  
Vol 385 (3) ◽  
pp. 1186-1200 ◽  
Author(s):  
J. S. Sanders ◽  
A. C. Fabian ◽  
S. W. Allen ◽  
R. G. Morris ◽  
J. Graham ◽  
...  
Keyword(s):  
X Ray ◽  
The Core ◽  
Cluster Of Galaxies

scholarly journals Indications for 3 Mpc-scale large-scale structure associated with an X-ray luminous cluster of galaxies at z = 0.95

2008 ◽  
Vol 481 (2) ◽  
pp. L73-L77 ◽  
Author(s):  
R. Fassbender ◽  
H. Böhringer ◽  
G. Lamer ◽  
C. R. Mullis ◽  
P. Rosati ◽  
...  
Keyword(s):  
Large Scale ◽  
Large Scale Structure ◽  
Scale Structure ◽  
X Ray ◽  
Cluster Of Galaxies

scholarly journals Cosmological Parameters from the X-Ray Evolution of Clusters

1999 ◽  
Vol 183 ◽  
pp. 243-243
Author(s):  
R.G. Bower ◽  
S.T. Kay
Keyword(s):  
Power Spectrum ◽  
Large Scale ◽  
Cosmological Parameters ◽  
Additional Constraint ◽  
Temperature Function ◽  
X Ray ◽  
The Core ◽  
Cluster Evolution ◽  
Poster Paper ◽  
Intracluster Gas

This poster paper presents an extension of the entropy-driven model of cluster evolution developed by Bower, 1997 (MN, 288, 355) in order to study the evolution of clusters in a low density universe. Our approach allows us to explicitly seperate the contributions from gravitational collapse and changes in the core entropy of the intracluster gas. Here, we apply the model to determine whether a preferred value of Ω0 is selected by currently available constraints (Figure 1). Measurements of the X-ray evolution of clusters cannot, by themselves, select out a particular cosmological model. An additional constraint on the effective power spectrum index (n) is required. This can either come from a measurement of the large-scale galaxy correlation function or from the shape of the present-day temperature function. A theoretical calculation of the Ω0 dependence of the power spectrum does not help break the inherent degeneracy.

Production of Prehistoric Southwestern Ceramics: A Low-Technology Approach

1996 ◽  
Vol 61 (2) ◽  
pp. 325-339 ◽  
Author(s):  
Yasushi Kojo
Keyword(s):  
Large Scale ◽  
X Ray ◽  
The Core ◽  
Ceramic Exchange ◽  
Peripheral Areas ◽  
Thin Section Analysis ◽  
The Right ◽  
Prehistoric Ceramics ◽  
Production Organization ◽  
Section Analysis

Production organization of Tusayan White and Gray wares (A.D. 850–1150) in northeastern Arizona was inferred from four independent lines of evidence: (1) association between temper class and geological zone, (2) distribution of intermediate pottery having characteristics of coterminous wares, (3) portable vessel frequencies in the core and peripheral areas, and (4) distribution of items and features related to pottery making. In spite of the propositions made by some scholars that specialized ceramic production and a large-scale ceramic exchange were the case, the present analysis strongly indicates the prevalence of household production with a minimal occurrence of exchange in the core area of these wares during the period. In the right circumstances, a low-technology approach is more useful than high-technology and high-cost approaches, e.g., neutron activation, X-ray emission, thin-section analysis, in the study of production and exchange of prehistoric ceramics.

scholarly journals AGES Observations of Abell1367 and its Outskirts

2006 ◽  
Vol 2 (S235) ◽  
pp. 196-196
Author(s):  
L. Cortese ◽  
R. F. Minchin ◽  
R. R. Auld ◽  
J. I. Davies ◽  
B. Catinella ◽  
...  
Keyword(s):  
Detection Limit ◽  
Preliminary Analysis ◽  
Cluster Core ◽  
Cluster Of Galaxies ◽  
Abell Cluster ◽  
Galaxy Environment

AbstractThe Arecibo Galaxy Environment Survey (AGES, Auld et al. 2006) will map ~200 square degrees over the next years using the ALFA feed array at the 305-m Arecibo Telescope. AGES is specifically designed to investigate various galactic environments from local voids to interacting groups and cluster of galaxies. AGES will map 20 square degrees in the Coma-Abell1367 supercluster including the Abell cluster 1367 and its outskirts (up to ~2 virial radii). In Spring 2006 we nearly completed the observations of 5 square degrees in the range 11:34< RA< 11:54, 19:20<Dec<20:20 covering all the cluster core and part of its infalling region reaching a 5 sigma detection limit of M(HI)~4×108M⊙ (assuming a velocity width ~200 km~s−1) at the distance of Abell1367 (~92 Mpc). An HI selected sample has been extracted from the datacube obtaining a catalogue of fluxes, recessional velocities, positions and velocity widths. We present a preliminary analysis of the properties of the HI sources and report the discovery of HI diffuse features within interacting groups at the periphery of Abell1367.

scholarly journals An X-ray and Radio Study of the Hubble Frontier Field Cluster Abell S1063

2021 ◽  
Author(s):  
Majidul Rahaman ◽  
Ramij Raja ◽  
Abhirup Datta ◽  
Jack O Burns ◽  
Brian Alden ◽  
...  
Keyword(s):  
Surface Brightness ◽  
Large Scale ◽  
High Fidelity ◽  
Radio Flux ◽  
X Ray ◽  
Radio Halo ◽  
Average Temperature ◽  
North East ◽  
The North ◽  
Cluster Of Galaxies

Abstract We present results from Chandra X-ray observations and 325 MHz Giant Metrewave Radio Telescope (GMRT) observations of the massive and X-ray luminous cluster of galaxies Abell S1063. We report the detection of large-scale “excess brightness” in the residual Chandra X-ray surface brightness map, which extends at least 2.7 Mpc towards the north-east from the center of the cluster. We also present a high fidelity X-ray flux and temperature map using Chandra archival data of 122 ksec, which shows the disturbed morphology in the cluster. The residual flux map shows the first observational confirmation of the merging axis proposed in earlier simulations. The average temperature within R500 is 11.7 ± 0.56 keV, which makes AS1063 one of the hottest clusters in the nearby Universe. The integrated radio flux density at 325 MHz is found to be 62.0 ± 6.3 mJy. The integrated spectrum of the radio halo follows a power-law with a spectral index α = −1.43 ± 0.13. The radio halo is found to be significantly under-luminous, which favored for both the hadronic as well as the turbulent re-acceleration mechanism for its origin.

scholarly journals X-Rays from Supernova 1993J and Ejecta Instabilities

1998 ◽  
Vol 188 ◽  
pp. 27-30
Author(s):  
K. Nomoto ◽  
T. Suzuki
Keyword(s):  
Light Curve ◽  
Large Scale ◽  
Gradual Increase ◽  
Spectral Feature ◽  
Early Time ◽  
X Rays ◽  
X Ray ◽  
The Core ◽  
Two Component ◽  
Large Scale Change

Among the mechanisms of X-ray emissions from supernovae, we focus on the circumstellar interaction. In particular, we relate the new X-ray features of SN1993J to the hydrodynamical instabilities in the ejecta. First, we model the early-time two component spectral feature by invoking instabilities in the dense cooling shell in the ejecta. Second, we model the gradual increase in the X-ray light curve as X-rays emitted from the reverse shocked ejecta; here the model requires a large scale change in the density distribution due to Rayleigh-Taylor instabilities around the core-envelope interface.

Pore scale imaging and modelling of coal properties

2015 ◽  
Vol 55 (2) ◽  
pp. 468
Author(s):  
Hamed Lamei Ramandi ◽  
Peyman Mostaghimi ◽  
Ryan T. Armstrong ◽  
Christoph H. Arns ◽  
Mohammad Saadatfar ◽  
...  
Keyword(s):  
Large Scale ◽  
Pore Space ◽  
Image Resolution ◽  
X Ray ◽  
Flow Simulations ◽  
The Core ◽  
Sensitivity Studies ◽  
X Ray Computed ◽  
3D Image Registration ◽  
Stress Dependent

A key parameter in determining the productivity and commercial success of coal seam gas wells is the permeability of individual seams. Laboratory testing of core plugs is commonly used as an indicator of potential seam permeability. The highly heterogeneous and stress-dependent nature of coal makes laboratory measurements difficult to perform and the results difficult to interpret. Consequently, permeability in coal is poorly understood. The permeability of coal at the core scale depends on the geometry, topology, connectivity, mineralisation and spatial distribution of the cleat system, and a better understanding of coal permeability, that and the factors that control this depends on having a better understanding and detailed characterisation of the system. The authors used high resolution micro-focus X-ray computed tomography and 2D-3D image registration techniques to overlay tomograms of the same core plug, with and without X-ray attenuating fluids present in the pore space, with 2D scanning electron microscope images to produce detailed 3D visualisations of the geometry and topology of the cleat systems in the coal plugs. Novel filtering algorithms were used to produce segmentations that preserve cleat aperture dimensions and together with large-scale fluid flow simulations, they performed directly on the images and were used to compute porosities and permeabilities. Image resolution and segmentation sensitivity studies are also described, which show that the core scale permeability is controlled by a small number of well-connected percolating cleats. The results of this study demonstrate the potential of simple image-based analysis techniques to provide rapid estimates of core plug permeabilities.

Large Scale Synthesis of BaTiO3 Nanorods by a Template Way

2009 ◽  
Vol 79-82 ◽  
pp. 373-376 ◽  
Author(s):  
Zhao Deng ◽  
Ying Dai ◽  
Hai Rui Liu ◽  
Wen Chen
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Large Scale ◽  
Template Method ◽  
Precipitation Process ◽  
X Ray ◽  
The Core ◽  
Transmission Electron ◽  
Scanning Electron

Large scale BaTiO3 nanorods were successfully synthesized by a template method based on a precipitation process. The templates used in our method are H2Ti8O17 nanorods, which can be synthesized from K2Ti4O9 fibers. The unique process of the synthesis is BaC2O4•0.5H2O shell was coated on the 1-dimensional H2Ti8O17 nanorods (the core). The as-prepared products were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results show that the BaTiO3 nanorods are ~100-300 nm in diameter and ~2-10 m in length. The process described provides a general route to fabricate this kind of perovskite 1-dimensional nanostructures, such as SrTiO3 and PbTiO3.

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